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Sample records for accelerator eta final

  1. GYMNOS Modeling of Electron Beam Dynamics for the Injector and Final Focus Regions of the ETA-II Accelerator

    NASA Astrophysics Data System (ADS)

    Kueny, C. S.; Wang, L.-F.; Chen, Y.-J.; Hewett, D. W.

    1999-11-01

    The 2-D axisymmetric PIC code GYMNOS has been used to model electron beam dynamics in the ETA-II accelerator at LLNL. Experiments on ETA-II seek to produce a high-brightness, low-emittance electron beam and deliver it to an X-ray converter target. These experiments are relevant to the DARHT II (Dual Axis Radiography Hydrodynamic Test) and AHF (Advanced Hydrotest Facility) projects, which will provide X-ray radiography diagnostics as part of the US Science-Based Stockpile Stewardship Program. We present simulations of both the ETA-II injector which produces the initial beam, and of the target region where X-ray generation occurs. GYMNOS employs the Embedded Curved Boundary (ECB) model to provide accurate beam modeling near the injector cathode and the target surfaces, and was recently upgraded with a non-uniform mesh to efficiently model the beam over a range of spatial scales. Modeling of the ETA-II injector has provided guidance on experimental parameters necessary for producing a high-quality beam for transport through the accelerator. Simulations of the target region have modeled the effects of backstreaming ions and backscattered electrons on beam dynamics, and investigated possible measures to minimize degradation in beam quality and final spot size.

  2. High brightness cathode experiments on the experimental test accelerator (ETA). Final report

    SciTech Connect

    Schlitt, L.; Proulx, G.

    1984-01-01

    The experiments performed on the ETA during the months of September through October of 1984 were intended to accomplish two objectives; to discover or develop a source capable of producing an electron beam whose brightness is substantially higher than that of previous sources, and to determine, if possible, the mechanisms which limit the source brightness so that further enhancements might be obtained. The results of the experiments met these objectives to a limited degree. A cathode material (velvet) and a diode geometry were identified which resulted in more than a factor of two improvements in brightness over that obtained with previous flashboard cathodes. Experiments were performed which have yielded information about mechanisms which may limit beam brightness, and have suggested approaches for further work to improve brightness. However, the desired brightness of 10/sup 5/ A/(cm/sup 2/-rad/sup 2/) was not achieved in these experiments. This report contains a discussion of the cathodes used, the diode geometries employed, the diagnostics, the typical characteristics of a single beam experiment, and the characteristics of the collimator used to measure the brightness. The entire ensemble of brightness data is presented and broken down into classes of experiments. In addition, the results of an EBQ calculation of one diode geometry are discussed, and differences between the results of similar experiments on ETA and ATA are noted. Finally, conclusions and recommendations are presented.

  3. Experimental test accelerator (ETA) II

    SciTech Connect

    Fessenden, T.J.; Atchison, W.L.; Birx, D.L.

    1981-03-06

    The Experimental Test Accelerator (ETA) is designed to produce a 10 kAmp electron beam at an energy of 4.5 MeV in 40 nsec pulses at an average rate of 2 pps. The accelerator also operates in bursts of 5 pulses spaced by as little as one millisec at an average rate of 5 pps. The machine is currently operating near 80% of its design values and has accumulated over 2.5 million pulses - mostly at a rate of one pps. The plasma cathode electron source, the remainder of the accelerator, and the operating characteristics of the machine are discussed.

  4. DARHT II Scaled Accelerator Tests on the ETA II Accelerator*

    SciTech Connect

    Weir, J T; Anaya Jr, E M; Caporaso, G J; Chambers, F W; Chen, Y; Falabella, S; Lee, B S; Paul, A C; Raymond, B A; Richardson, R A; Watson, J A; Chan, D; Davis, H A; Day, L A; Scarpetti, R D; Schultze, M E; Hughes, T P

    2005-05-26

    The DARHT II accelerator at LANL is preparing a series of preliminary tests at the reduced voltage of 7.8 MeV. The transport hardware between the end of the accelerator and the final target magnet was shipped to LLNL and installed on ETA II. Using the ETA II beam at 5.2 MeV we completed a set of experiments designed reduce start up time on the DARHT II experiments and run the equipment in a configuration adapted to the reduced energy. Results of the beam transport using a reduced energy beam, including the kicker and kicker pulser system will be presented.

  5. ETA-II accelerator upgrades

    SciTech Connect

    Nilson, D.G.; Deadrick, F.J.; Hibbs, S.M.; Sampayan, S.E.; Petersen, D.E.

    1991-09-01

    We discuss recent improvements to the ETA-II linear induction electron accelerator. The accelerator`s cells have been carefully reconditioned to raise the maximum accelerating gap voltage from approximately 100 kV to 125 kV. Insulators of Rexolite plastic in a new ``zero-gap`` arrangement replaced the alumina originals after several alternative materials were investigated. A new multi-cable current feed system will be used to eliminate pulse reflection interactions encountered in earlier experiments. Improved alignment fixtures have been installed to help minimize beam perturbation due to poorly aligned intercell magnets between 10-cell groups. A stretched wire alignment technique (SWAT) has been utilized to enhance overall magnetic alignment, and to characterize irreducible alignment errors. These changes are in conjunction with an expansion of the accelerator from a 20-cell to a 60-cell configuration. When completed, the upgraded accelerator is expected to deliver 2.5 kA of electron beam current at 7.5 MeV in bursts of up to fifty 70-ns pulses at a 5-kHz repetition rate. A 5.5-meter-long wiggler will convert the energy into 3-GW microwave pulses at 140 GHz for plasma heating experiments in the Microwave Tokamak Experiment (MTX).

  6. ETA-II accelerator upgrades

    SciTech Connect

    Nilson, D.G.; Deadrick, F.J.; Hibbs, S.M.; Sampayan, S.E.; Petersen, D.E.

    1991-09-01

    We discuss recent improvements to the ETA-II linear induction electron accelerator. The accelerator's cells have been carefully reconditioned to raise the maximum accelerating gap voltage from approximately 100 kV to 125 kV. Insulators of Rexolite plastic in a new zero-gap'' arrangement replaced the alumina originals after several alternative materials were investigated. A new multi-cable current feed system will be used to eliminate pulse reflection interactions encountered in earlier experiments. Improved alignment fixtures have been installed to help minimize beam perturbation due to poorly aligned intercell magnets between 10-cell groups. A stretched wire alignment technique (SWAT) has been utilized to enhance overall magnetic alignment, and to characterize irreducible alignment errors. These changes are in conjunction with an expansion of the accelerator from a 20-cell to a 60-cell configuration. When completed, the upgraded accelerator is expected to deliver 2.5 kA of electron beam current at 7.5 MeV in bursts of up to fifty 70-ns pulses at a 5-kHz repetition rate. A 5.5-meter-long wiggler will convert the energy into 3-GW microwave pulses at 140 GHz for plasma heating experiments in the Microwave Tokamak Experiment (MTX).

  7. Search for B Meson Decays to eta' eta' K

    SciTech Connect

    Aubert, B.

    2006-05-05

    The authors describe searches for decays of B mesons to the charmless final states {eta}'{eta}'K. The data consist of 228 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation, collected with the BABAR detector at the Stanford Linear Accelerator Center. The 90% confidence level upper limits for the branching fractions are {Beta}(B{sup 0} {yields} {eta}'{eta}'K{sup 0}) < 31 x 10{sup -6} and {Beta}(B{sup +} {yields} {eta}'{eta}'K{sup +}) < 25 x 10{sup -6}.

  8. Preliminary assessment of the electromagnetic environment in the immediate vicinity of the ETA accelerator

    SciTech Connect

    Cabayan, H.S.; Bogdan, E.; Zicker, J.; Wythe, D.; Burke, G.J.

    1980-04-01

    The electromagnetic fields in the immediate vicinity of the Experimental Test Accelerator (ETA) at the Lawrence Livermore Laboratory have been characterized. Various EM sensors that cover the frequency band from the very low frequencies up into the GHz region have been used. The report describes in detail the probes, the test set-up and the data processing techniques.

  9. Measurements of reduced corkscrew motion on the ETA-II linear induction accelerator

    SciTech Connect

    Allen, S.L.; Brand, H.R.; Chambers, F.W.; Chen, Y.J.; Coffield, F.E.; Deadrick, F.J.; Griffith, L.V.; Lager, D.L.; Mauer, W.J.; Nexsen, W.E.; Paul, A.C.; Sampayan, S.; Turner, W.C.

    1991-05-01

    The ETA-II linear induction accelerator is used to drive a microwave free electron laser (FEL). Corkscrew motion, which previously limited performance, has been reduced by: (1) an improved pulse distribution system which reduces energy sweep, (2) improved magnetic alignment achieved with a stretched wire alignment technique (SWAT) and (3) a unique magnetic tuning algorithm. Experiments have been carried out on a 20-cell version of ETA-II operating at 1500 A and 2.7 MeV. The measured transverse beam motion is less than 0.5 mm for 40 ns of the pulse, an improvement of a factor of 2 to 3 over previous results. Details of the computerized tuning procedure, estimates of the corkscrew phase, and relevance of these results to future FEL experiments are presented. 11 refs.

  10. PARTICLE ACCELERATION IN THE EXPANDING BLAST WAVE OF {eta} CARINA'S GREAT ERUPTION OF 1843

    SciTech Connect

    Ohm, S.; Domainko, W.; Hinton, J. A. E-mail: wilfried.domainko@mpi-hd.mpg.d

    2010-08-01

    Non-thermal hard X-ray and high-energy (HE; 1 MeV {<=} E {<=} 100 GeV) {gamma}-ray emission in the direction of {eta} Carina has been recently detected using the INTEGRAL, AGILE, and Fermi satellites. So far this emission has been interpreted in the framework of particle acceleration in the colliding wind region between the two massive stars. However, the existence of a very fast moving blast wave which originates in the historical 1843 'Great Eruption' provides an alternative particle acceleration site in this system. Here, we explore an alternate scenario and find that inverse Compton emission from electrons accelerated in the blast wave can naturally explain both the flux and spectral shape of the measured hard X-ray and HE {gamma}-ray emission. This scenario is further supported by the lack of significant variability in the INTEGRAL and Fermi measured fluxes.

  11. B-meson decays to eta' rho, eta' f0, and eta' K*

    SciTech Connect

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2010-08-25

    We present measurements of B-meson decays to the final states {eta}{prime} {rho}, {eta}{prime} f{sub 0}, and {eta}{prime} K*, where K* stands for a vector, scalar, or tensor strange meson. We observe a significant signal or evidence for {eta}{prime} {rho}{sup +} and all the {eta}{prime}K* channels. We also measure, where applicable, the charge asymmetries, finding results consistent with no direct CP violation in all cases. The measurements are performed on a data sample consisting of 467 x 10{sup 6} B{bar B} pairs, collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. Our results favor the theoretical predictions from perturbative QCD and QCD Factorization and we observe an enhancement of the tensor K*{sub 2} (1430) with respect to the vector K*(892) component.

  12. Branching Fraction Limits for B0 Decays to eta' eta, eta' pi0 and eta pi0

    SciTech Connect

    Aubert, B.

    2006-03-10

    We describe searches for decays to two-body charmless final states {eta}'{eta}, {eta}'{pi}{sup 0} and {eta}{pi}{sup 0} of B{sup 0} mesons produced in e{sup +}e{sup -} annihilation. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 232 million produced B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup 0} {yields} {eta}'{eta}) = 0.2{sub -0.5}{sup +0.7} {+-} 0.4 (< 1.7), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.6{sub -0.4}{sup +0.5} {+-} 0.1 (< 1.3), and {Beta}(B{sup 0} {yields} {eta}'{pi}{sup 0}) = 0.8{sub -0.6}{sup +0.8} {+-} 0.1 (< 2.1). The first error quoted is statistical and the second systematic.

  13. Advanced Accelerator Concepts Final Report

    SciTech Connect

    Wurtele, Jonathan S.

    2014-05-13

    physics motivation for our experiment, one that requires only a few dozen researchers but must effectively integrate plasma, accelerator, atomic, and fundamental physics, as well as combine numerous technologies in the control, manipulation, and measurement of neutral and non-neutral particles. The ELENA ring (to which we hope to contribute, should funding be provided) is expect, when completed, to significantly enhance the performance of antihydrogen trapping by increasing by a factor of 100 the number of antiprotons that can be successfully trapped and cooled. ELENA operation is scheduled to commence in 2017. In collaboration with LBNL scientists, we proposed a frictional cooling scheme. This is an alternative cooling method to that used by ELENA. It is less complicated, experimentally unproven, and produces a lower yield of cold antiprotons. Students and postdoctoral researchers work on the trapping, cooling, transport, and nonlinear dynamics of antiprotons bunches that are provided by the AD to ALPHA; they contribute to the operation of the experiment, to software development, and to the design and operation of experiments. Students are expected to spend at summers at CERN while taking courses; after completion of courses they typically reside at CERN for most of the half-year run. The Antiproton Decelerator [AD] at CERN, along with its experiments, is the only facility in the world where antiprotons can be trapped and cooled and combined with positrons to form cold antihydrogen, with the ultimate goal of studying CPT violation and, subsequently, gravitational interactions of antimatter. Beyond the ALPHA experiment, the group worked on beam physics problems including limits on the average current in a time-dependent period cathode and new methods to create longitudinally coherent high repetition rate soft x-ray sources and wide bandwidth mode locked x-ray lasers. We completed a detailed study of quantum mechanical effects in the transit time cooling of muons.

  14. The ETA-II linear induction accelerator and IMP wiggler: A high-average-power millimeter-wave free-electron-laser for plasma heating

    SciTech Connect

    Allen, S.L.; Scharlemann, E.T.

    1992-05-01

    We have constructed a 140-GHz free-electron laser to generate high-average-power microwaves for heating the MTX tokamak plasma. A 5.5-m steady-state wiggler (intense Microwave Prototype-IMP) has been installed at the end of the upgraded 60-cell ETA-II accelerator, and is configured as an FEL amplifier for the output of a 140-GHz long-pulse gyrotron. Improvements in the ETA-II accelerator include a multicable-feed power distribution network, better magnetic alignment using a stretched-wire alignment technique (SWAT). and a computerized tuning algorithm that directly minimizes the transverse sweep (corkscrew motion) of the electron beam. The upgrades were first tested on the 20-cell, 3-MeV front end of ETA-II and resulted in greatly improved energy flatness and reduced corkscrew motion. The upgrades were then incorporated into the full 60-cell configuration of ETA-II, along with modifications to allow operation in 50-pulse bursts at pulse repetition frequencies up to 5 kHz. The pulse power modifications were developed and tested on the High Average Power Test Stand (HAPTS), and have significantly reduced the voltage and timing jitter of the MAG 1D magnetic pulse compressors. The 2-3 kA. 6-7 MeV beam from ETA-II is transported to the IMP wiggler, which has been reconfigured as a laced wiggler, with both permanent magnets and electromagnets, for high magnetic field operation. Tapering of the wiggler magnetic field is completely computer controlled and can be optimized based on the output power. The microwaves from the FEL are transmitted to the MTX tokamak by a windowless quasi-optical microwave transmission system. Experiments at MTX are focused on studies of electron-cyclotron-resonance heating (ECRH) of the plasma. We summarize here the accelerator and pulse power modifications, and describe the status of ETA-II, IMP, and MTX operations.

  15. IR (infrared radiation) observations of the ETA (Experimental Test Accelerator) beam channel. Technical report

    SciTech Connect

    McKenzie, D.L.; Ditteon, R.P.; Frazier, E.N.; Giguere, R.P.; Rice, C.J.

    1985-09-30

    Aerospace Corporation scientists observed infrared radiation from the ETA beam channel in the wavelength range 0.65 -14.4 micrometer on September 12-16, 1983. The data consisted of time profiles of radiation pulses from the beam channel, measured with a limiting time resolution of 100 nanoseconds. Isolation of spectral bands was achieved through the use of broadband filters and circular variable filters (CVF). The latter had resolution lambda/delta lambda = 50 - 100, where lambda is wavelength. A total of 1076 radiation pulses were recorded. The beam propagation tube was filled with either ambient laboratory air or synthetic (dry) air at pressures ranging from 0.05 Torr to 500 Torr.

  16. Observation of B^+\\to\\eta\\rho^+ and Search for B^0 Decays to\\eta^\\prime\\eta, \\eta\\pi^0, \\eta^\\prime\\pi^0, and \\omega\\pi^0

    SciTech Connect

    Aubert, Bernard; Bona, Marcella; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, Antimo; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, Marco; Brown, D.N.; Button-Shafer, Janice; Cahn, Robert N.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /INFN, Pisa /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2008-04-22

    The authors present measurements of branching fractions for five B-meson decays to two-body charmless final states. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 459 million B{bar B} pairs. The results for branching fractions are, in units of 10{sup -6} (upper limits at 90% C.L.): {Beta}(B{sup +} {yields} {eta}{rho}{sup +}) = 9.9 {+-} 1.2 {+-} 0.8, {Beta}(B{sup 0} {yields} {eta}{prime}{eta}) = 0.5 {+-} 0.4 {+-} 0.1 (< 1.2), {Beta}(B{sup 0} {yields} {eta}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), {Beta}(B{sup 0} {yields} {eta}{prime}{pi}{sup 0}) = 0.9 {+-} 0.4 {+-} 0.1 (< 1.5), and {Beta}(B{sup 0}{sup 0} {yields} {omega}{pi}{sup 0}) = {eta}{rho}{sup +} mode, they measure the charge asymmetry {Alpha}{sub ch} (B{sup +} {yields} {eta}{rho}{sup +}) = 0.13 {+-} 0.11 {+-} 0.02.

  17. Modified betatron accelerator studies. Final report

    SciTech Connect

    Hughes, T.P.; Godfrey, B.B.

    1984-12-01

    This final report describes work carried out on the equilibrium and stability properties of circular accelerators. A rigid-disk beam model in which the fields are treated exactly is used to study linear instabilities. This approach has uncovered an important inductive effect which at high toroidal mode numbers leads to either stability or to a hybrid instability. A corresponding effect has been found in electron-layer geometry. The new theory also shows that moving the equilibrium position toward the inner wall can stabilize low mode numbers. With the aid of IVORY code simulation results it is shown that the transverse motion of beam partilces is a key factor in determining beam stability. The upper bound on particle circulation frequency spread is shown to be a function only of the beam major and minor radii. This leads to upper bounds on stable currents in the modified betatron. Numerical results on stability in the stellatron and reversing-solenoidal-lens betatrons are presented. In addition, the sensitivity of equilibrium particle orbits in the stellatron to initial conditions is calculated.

  18. B meson decays to charmless meson pairs containing eta or eta'

    SciTech Connect

    Aubert, : B.

    2009-12-14

    The authors present updated measurements of the branching fractions for B{sup 0} meson decays to {eta}K{sup 0}, {eta}{eta}, {eta}{phi}, {eta}{omega}, {eta}{prime}K{sup 0}, {eta}{prime}{eta}{prime}, {eta}{prime}, {phi}, and {eta}{prime}{omega} and branching fractions and CP-violating charge asymmetries for B{sup +} decays to {eta}{pi}{sup +}, {eta}K{sup +}, {eta}{prime}{pi}{sup +}, and {eta}{prime} K{sup +}. The data represent the full dataset of 467 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. Besides large signals for the four charged B decays modes and for B{sup 0} {yields} {eta}{prime}K{sup 0}, they find evidence for three B{sup 0} decays modes at greater than 3.0{sigma} significance. They find {Beta}(B{sup 0} {yields} {eta}K{sup 0}) = (1.15{sub -0.38}{sup +0.43} {+-} 0.09) x 10{sup -6}, {Beta}(B{sup 0} {yields} {eta}{omega}) = (0.94{sub -0.30}{sup +0.35} {+-} 0.09) x 10{sup -6}, and {Beta}(B{sup 0} {yields} {eta}{prime}{omega}) = (1.01{sub -0.38}{sup +0.46} {+-} 0.09) x 10{sup -6}, where the first (second) uncertainty is statistical (systematic). For the B{sup +} {yields} {eta}K{sup +} decay mode, they measure the charge asymmetry {Alpha}{sub ch} (B{sup +} {yields} {eta}K{sup +}) = -0.36 {+-} 0.11 {+-} 0.03.

  19. eta. prime -. eta. -. pi. sup 0 mixing

    SciTech Connect

    Bagchi, B. ); Lahiri, A. ); Niyogi, S. )

    1990-05-01

    We have examined the saturation of anomalous Ward identities by the low-lying pseudoscalars {pi}{sup 0}, {eta}, and {eta}{prime} to determine the sizes of {eta}{prime}-{eta}, {pi}{sup 0}-{eta}, and {pi}{sup 0}-{eta}{prime} mixing angles. The {eta}{prime}-{eta} mixing angle turns out to be about {minus}20{degree} which is consistent with the recent findings. Our estimate for the {pi}{sup 0}-{eta} mixing angle shows that it could be bigger than the older value obtained from the {rho}-{omega} mixing, baryon mass splittings, and kaon mass difference.

  20. Searches for Charmless Decays B0 --> eta omega, B0 --> eta K0, B+ --> eta rho+, and B+ --> eta' pi+

    SciTech Connect

    Aubert, B

    2004-08-13

    The authors report results for measurements of the decay branching fractions of B{sup 0} to the charmless final states {eta}{omega} and {eta}K{sup 0}, and of B{sup +} to {eta}{rho}{sup +} and {eta}'{pi}{sup +}. None of these decays have been observed definitively. Measurements of the related decays B{sup +} --> {eta}K{sup +}, B{sup +} --> {eta}{pi}{sup +}, and B --> {eta}'K were published recently. Charmless decays with kaons are usually expected to be dominated by b --> s loop (''penguin'') transitions, while b --> u tree transitions are typically larger for the decays with pions and {rho} mesons. However the B --> {eta}K decays are especially interesting since they are suppressed relative to the abundant B --> {eta}'K decays due to destructive interference between two penguin amplitudes. The CKM-suppressed b --> u amplitudes may interfere significantly with penguin amplitudes, possibly leading to large direct CP violation in B{sup +} --> {eta}{rho}{sup +} and B{sup +} --> {eta}'{pi}{sup +}; numerical estimates are available in a few cases. The authors search for such direct CP violation by measuring the charge asymmetry A{sub ch} {equivalent_to} ({Gamma}{sup -} - {Gamma}{sup +})/({Gamma}{sup -} + {Gamma}{sup +}) in the rates {Gamma}{sup {+-}} = {Gamma}(B{sup {+-}} --> f{sup {+-}}), for each observed charged final state f{sup {+-}}. Charmless B decays are becoming useful to test the accuracy of theoretical predictions. Phenomenological fits to the branching fractions and charge asymmetries can be used to understand the importance of tree and penguin contributions and may provide sensitivity to the CKM angle {gamma}.

  1. Eta(547) and Eta(958) Meson Photoproduction on the Proton

    SciTech Connect

    Michael Dugger

    2001-12-01

    Photoproduction of {eta} and {eta}{prime} mesons has been studied at the Continuous Electron Beam Accelerator Facility (CEBAF) Large Acceptance Spectrometer (CLAS) using a tagged photon beam incident on a hydrogen target with photon energies from the respective production thresholds up to 2.4 GeV. The photoproduced mesons were identified via missing mass reconstruction using recoil proton momentum and time of flight information. Data were obtained in a range of {radical}s from threshold to 2.2 GeV for each meson. In this study, differential cross-section measurements for the {gamma}p {yields} p{eta} and {gamma}p {yields} p{eta}{prime} reactions are presented, and the results compared to recent data. An isobar analysis of the differential cross-sections is performed. The predicted differential cross-sections from the isobar analysis are used to predict behavior in unmeasured regions of phase space, and to infer total cross sections. For the {gamma}p {yields} p{eta} reaction, a value of the S{sub 11}(1535) proton helicity amplitude also was extracted and compared to recent analyses. The data presented greatly extends the energy and angle coverage for differential cross-sections of {eta} photoproduction, and significantly improves the accuracy with which {eta}{prime} cross sections are known.

  2. Searches for B0 Decays to eta K0, eta eta,eta' eta', eta phi, and eta'phi

    SciTech Connect

    Aubert, B.

    2006-07-31

    The authors search for B{sup 0} meson decays into two-body combinations of K{sup 0}, {eta}, {eta}', and {phi} mesons in 324 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. They measure the following branching fractions (upper limits at 90% confidence level) in units of 10{sup -6}: {Beta}(B{sup 0} {yields} {eta}K{sup 0}) = 1.8{sub -0.6}{sup +0.7} {+-} 0.1 (< 2.9), {Beta}(B{sup 0} {yields} {eta}{eta}) = 1.1{sub -0.4}{sup +0.5} {+-} 0.1(< 1.8), {Beta}(B{sup 0} {yields} {eta}{phi}) = 0.1 {+-} 0.2 {+-} 0.1(< 0.6), {Beta}(B{sup 0} {yields} {eta}'{phi}) = 0.2{sub -0.3}{sup +0.4} {+-} 0.1(< 1.0), and {Beta}(B{sup 0} {yields} {eta}'{eta}') = 1.0{sub -0.6}{sup +0.8} {+-} 0.1 (< 2.4), where the first error is statistical and the second systematic.

  3. Photoproduction of eta-mesic 3He.

    PubMed

    Pfeiffer, M; Ahrens, J; Annand, J R M; Beck, R; Caselotti, G; Cherepnya, S; Föhl, K; Fog, L S; Hornidge, D; Janssen, S; Kashevarov, V; Kondratiev, R; Kotulla, M; Krusche, B; McGeorge, J C; MacGregor, I J D; Mengel, K; Messchendorp, J G; Metag, V; Novotny, R; Rost, M; Sack, S; Sanderson, R; Schadmand, S; Thomas, A; Watts, D P

    2004-06-25

    The photoproduction of eta-mesic 3He has been investigated using the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI. The total inclusive cross section for the reaction gamma3He-->etaX has been measured for photon energies from threshold to 820 MeV. The total and angular differential coherent eta cross sections have been extracted up to energies of 745 MeV. A resonancelike structure just above the eta production threshold with an isotropic angular distribution suggests the existence of a resonant quasibound state. This is supported by studies of a competing decay channel of such a quasibound eta-mesic nucleus into pi(0)pX. A binding energy of (-4.4+/-4.2) MeV and a width of (25.6+/-6.1) MeV is deduced for the quasibound eta-mesic state in 3He. PMID:15244998

  4. Observation of B-->eta'K* and evidence for B+-->eta'rho+.

    PubMed

    Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Chauveau, J; Briand, H; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; John, M J J; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Panetta, J; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Safai Tehrani, F; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; De Groot, N; Franek, B; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Legendre, M; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Martinez-Vidal, F; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Mellado, B; Mihalyi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2007-02-01

    We present an observation of B-->eta'K*. The data sample corresponds to 232x10(6) BB[over ] pairs collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the Stanford Linear Accelerator Center. We measure the branching fractions (in units of 10(-6)) B(B(0)-->eta'K*0)=3.8+/-1.1+/-0.5 and B(B+-->eta'K*+)=4.9(1.7)(+1.9)+/-0.8, where the first error is statistical and the second systematic. A simultaneous fit results in the observation of B-->eta'K* with B(B-->eta'K*)=4.1(-0.9)(+1.0)+/-0.5. We also search for B-->eta'rho and eta'f(0)(980)(f(0)-->pi+pi-) with results and 90% confidence level upper limits B(B+-->eta'rho+)=8.7(-2.8-1.3)(+3.1+2.3) (<14), B(B(0)-->eta'rho0)<3.7, and B(B(0)-->eta'f(0)(980)(f(0)-->pi+pi-))<1.5. Charge asymmetries in the channels with significant yields are consistent with zero. PMID:17358844

  5. Measurement of the Color-Suppressed B0->D(*)0 pi0 /omega/eta/eta Prime Branching Fractions

    SciTech Connect

    Prudent, X

    2008-11-05

    The authors report results on the branching fraction (BF) measurement of the color-suppressed decays {bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}, D*{sup 0}{pi}{sup 0}, D{sup 0}{eta}, D*{sup 0}{eta}, D{sup 0}{omega}, D*{sup 0}{omega}, D{sup 0}{eta}{prime}, and D*{sup 0}{eta}{prime}. They measure the branching fractions BF(D{sup 0}{pi}{sup 0}) = (2.78 {+-} 0.08 {+-} 0.20) x 10{sup -4}, BF(D*{sup 0}{pi}{sup 0}) = (1.78 {+-} 0.13 {+-} 0.23) x 10{sup -4}, BF(D{sup 0}{eta}) = (2.41 {+-} 0.09 {+-} 0.17) x 10{sup -4}, BF(D*{sup 0}{eta}) = (2.32 {+-} 0.13 {+-} 0.22) x 10{sup -4}, BF(D{sup 0}{omega}) = (2.77 {+-} 0.13 {+-} 0.22) x 10{sup -4}, BF(D*{sup 0}{omega}) = (4.44 {+-} 0.23 {+-} 0.61) x 10{sup -4}, BF(D{sup 0}{eta}{prime}) = (1.38 {+-} 0.12 {+-} 0.22) x 10{sup -4} and BF(D*{sup 0}{eta}{prime}) = (1.29 {+-} 0.23 {+-} 0.23) x 10{sup -4}, where the first uncertainty is statistical and the second is systematic. The result is based on a sample of (454 {+-} 5) x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance from 1999 to 2007, with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center. The measurements are compared to theoretical predictions by factorization, SCET and pQCD. The presence of final state interactions predictions by factorization, SCET and pQCD. The presence of final state interactions is confirmed and the measurements seem to be more in favor of SCET compared to pQCD.

  6. Field Operations Program Chevrolet S-10 (Lead-Acid) Accelerated Reliability Testing - Final Report

    SciTech Connect

    J. Francfort; J. Argueta; M. Wehrey; D. Karner; L. Tyree

    1999-07-01

    This report summarizes the Accelerated Reliability testing of five lead-acid battery-equipped Chevrolet S-10 electric vehicles by the US Department of Energy's Field Operations Program and the Program's testing partners, Electric Transportation Applications (ETA) and Southern California Edison (SCE). ETA and SCE operated the S-10s with the goal of placing 25,000 miles on each vehicle within 1 year, providing an accelerated life-cycle analysis. The testing was performed according to established and published test procedures. The S-10s' average ranges were highest during summer months; changes in ambient temperature from night to day and from season-to-season impacted range by as much as 10 miles. Drivers also noted that excessive use of power during acceleration also had a dramatic effect on vehicle range. The spirited performance of the S-10s created a great temptation to inexperienced electric vehicle drivers to ''have a good time'' and to fully utilize the S-10's acceleration capability. The price of injudicious use of power is greatly reduced range and a long-term reduction in battery life. The range using full-power accelerations followed by rapid deceleration in city driving has been 20 miles or less.

  7. Measurement of branching fractions and charge asymmetries in B+ decays to eta pi+, eta K+, eta rho+, and eta' pi+, and search for B0 decays to eta K0 and eta omega.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges-Pous, E; Palano, A; Pappagallo, M; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morg An, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Kelly, M P; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bondioli, M; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Del Re, D; Hadavand, H K; Hill, E J; Macfarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Derrington, I M; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Zhang, J; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Nogowski, R; Otto, S; Petzold, A; Schott, G; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Pierini, M; Plaszczynski, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; John, M J J; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Biasini, M; Covarelli, R; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Simi, G; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Tehrani, F Safai; Voena, C; Christ, S; Schröder, H; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Gopal, G P; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Graziani, G; Hamel de Monchenault, G; Kozanecki, W; Legendre, M; London, G W; Mayer, B; Vasseur, G; Yèche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Abe, T; Allen, M T; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Claus, R; Convery, M R; Cristinziani, M; Dingfelder, J C; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Mohapatra, A K; Muller, D R; O'grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Soha, A; Stelzer, J; Strube, J; Su, D; Sullivan, M K; Thompson, J M; Va'vra, J; Wagner, S R; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Martinez-Vidal, F; Panvini, R S; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Jackson, P D; Kowalewski, R; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Flood, K T; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mellado, B; Mihalyi, A; Pan, Y; Prepost, R; Tan, P; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2005-09-23

    We present measurements of branching fractions and charge asymmetries for six B-meson decay modes with an eta or eta(') meson in the final state. The data sample corresponds to 232 x 10(6) BB pairs collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) B Factory at SLAC. We measure the branching fractions (in units of 10(-6)): B(B+ -->eta pi(+))=5.1+/-0.6+/-0.3, B(B+ etaK+)=3.3+/-0.6+/-0.3, B(B0-->etaK0)=1.5+/-0.7+/-0.1 (<2.5 at 90% C.L.), B(B+-->eta rho(+))=8.4+/-1.9+/-1.1, B(B0-->eta omiga)=1.0+/-0.5+/-0.2 (<1.9 at 90% C.L.), and B(B+-->eta(')pi(+))=4.0+/-0.8+/-0.4, where the first uncertainty is statistical and second systematic. For the charged modes we also determine the charge asymmetries, all found to be compatible with zero. PMID:16197132

  8. Eta-nucleon interaction and nuclear production of eta mesons

    SciTech Connect

    Liu, L.C.

    1993-08-01

    Eta-nucleon interaction and eta-nucleus dynamics are discussed. The possibility of using {eta} to probe unnatural-parity nuclear states and to study spin-isospin correlations between two nucleons are demonstrated.

  9. BIOCONAID System (Bionic Control of Acceleration Induced Dimming). Final Report.

    ERIC Educational Resources Information Center

    Rogers, Dana B.; And Others

    The system described represents a new technique for enhancing the fidelity of flight simulators during high acceleration maneuvers. This technique forces the simulator pilot into active participation and energy expenditure similar to the aircraft pilot undergoing actual accelerations. The Bionic Control of Acceleration Induced Dimming (BIOCONAID)…

  10. Search For {eta}-Bound Nuclei

    SciTech Connect

    Machner, H.

    2011-10-24

    The {eta} meson can be bound to atomic nuclei. Experimental search is discussed in the form of final state interaction for the reactions dp{yields}{sup 3}He{eta} and dd{yields}{sup 4}He{eta}. For the latter case tensor polarized deuterons were used in order to extract the s-wave strength. For both reactions complex scattering lengths are deduced: In a two-nucleon transfer reaction under quasi-free conditions, p{sup 27}Al{yields}{sup 3}HeX, was investigated. The system X can be the bound {sup 25}Mg x {eta} at rest. When a possible decay of an intermediate N{sup *}(1535) is required, a highly significant bump shows up in the missing mass spectrum. The data give for a bound state a binding energy of 13.3{+-}1.6 MeV and a width of {sigma} = 4.4{+-}1.3 MeV.

  11. Final report on the LLNL compact torus acceleration project

    SciTech Connect

    Eddleman, J.; Hammer, J.; Hartman, C.; McLean, H.; Molvik, A.

    1995-03-19

    In this report, we summarize recent work at LLNL on the compact torus (CT) acceleration project. The CT accelerator is a novel technique for projecting plasmas to high velocities and reaching high energy density states. The accelerator exploits magnetic confinement in the CT to stably transport plasma over large distances and to directed kinetic energies large in comparison with the CT internal and magnetic energy. Applications range from heating and fueling magnetic fusion devices, generation of intense pulses of x-rays or neutrons for weapons effects and high energy-density fusion concepts.

  12. Materials, Strands, and Cables for Superconducting Accelerator Magnets. Final Report

    SciTech Connect

    Sumption, Mike D.; Collings, Edward W.

    2014-09-19

    This report focuses on Materials, Strands and Cables for High Energy Physics Particle accelerators. In the materials area, work has included studies of basic reactions, diffusion, transformations, and phase assemblage of Nb3Sn. These materials science aspects have been married to results, in the form of flux pinning, Bc2, Birr, and transport Jc, with an emphasis on obtaining the needed Jc for HEP needs. Attention has also been paid to the “intermediate-temperature superconductor”, magnesium diboride emphasis being placed on (i) irreversibility field enhancement, (ii) critical current density and flux pinning, and (iii) connectivity. We also report on studies of Bi-2212. The second area of the program has been in the area of “Strands” in which, aside from the materials aspect of the conductor, its physical properties and their influence on performance have been studied. Much of this work has been in the area of magnetization estimation and flux jump calculation and control. One of the areas of this work was strand instabilities in high-performance Nb3Sn conductors due to combined fields and currents. Additionally, we investigated quench and thermal propagation in YBCO coated conductors at low temperatures and high fields. The last section, “Cables”, focussed on interstrand contact resistance, ICR, it origins, control, and implications. Following on from earlier work in NbTi, the present work in Nb3Sn has aimed to make ICR intermediate between the two extremes of too little contact (no current sharing) and too much (large and unacceptable magnetization and associated beam de-focussing). Interstrand contact and current sharing measurements are being made on YBCO based Roebel cables using transport current methods. Finally, quench was investigated for YBCO cables and the magnets wound from them, presently with a focus on 50 T solenoids for muon collider applications.

  13. Study of B Meson Decays with Excited eta and eta-prime Mesons

    SciTech Connect

    Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; /Energy Sci. Network /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /Frascati /Genoa U. /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /Pisa U. /Prairie View A-M /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2008-04-18

    Using 383 million B{bar B} pairs from the BABAR data sample, they report results for branching fractions of six charged B-meson decay modes, where a charged kaon recoils against a charmless resonance decaying to K{bar K}* or {eta}{pi}{pi} final states with mass in the range (1.2-1.8) GeV/c{sup 2}. They observe a significant enhancement at the low K{bar K}* invariant mass which is interpreted as B{sup +} {yields} {eta}(1475)K{sup +}, find evidence for the decay B{sup +} {yields} {eta}(1295)K{sup +}, and place upper limits on the decays B{sup +} {yields} {eta}(1405)K{sup +}, B{sup +} {yields} f{sub 1}(1285)K{sup +}, B{sup +} {yields} f{sub 1}(1420)K{sup +}, and B{sup +} {yields} {phi}(1680)K{sup +}.

  14. Branching Fraction and P-violation Charge Asymmetry Measurements for B-meson Decays to eta K+-, eta pi+-, eta'K, eta' pi+-, omega K, and omega pi+-

    SciTech Connect

    Aubert, B.

    2007-06-28

    The authors present measurements of the branching fractions for B{sup 0} meson decays to {eta}{prime}K{sup 0} and {omega}K{sup 0}, and of the branching fractions and CP-violation charge asymmetries for B{sup +} meson decays to {eta}{pi}{sup +}, {eta}K{sup +}, {eta}{prime}{pi}{sup +}, {eta}{prime}K{sup +}, {omega}{pi}{sup +}, and {omega}K{sup +}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 383 million B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The measurements agree with previous results; they find no evidence for direct CP violation.

  15. The final technical report of the CRADA, 'Medical Accelerator Technology'

    SciTech Connect

    Chu, W.T.; Rawls, J.M.

    2000-06-12

    Under this CRADA, Berkeley Lab and the industry partner, General Atomics (GA), have cooperatively developed hadron therapy technologies for commercialization. Specifically, Berkeley Lab and GA jointly developed beam transport systems to bring the extracted protons from the accelerator to the treatment rooms, rotating gantries to aim the treatment beams precisely into patients from any angle, and patient positioners to align the patient accurately relative to the treatment beams. We have also jointly developed a patient treatment delivery system that controls the radiation doses in the patient, and hardware to improve the accelerator performances, including a radio-frequency ion source and its low-energy beam transport (LEBT) system. This project facilitated the commercialization of the DOE-developed technologies in hadron therapy by the private sector in order to improve the quality of life of the nation.

  16. Single particles accelerate final stages of capillary break-up

    NASA Astrophysics Data System (ADS)

    Lindner, Anke; Fiscina, Jorge Eduardo; Wagner, Christian

    2015-06-01

    Droplet formation of suspensions is present in many industrial and technological processes such as coating and food engineering. Whilst the finite-time singularity of the minimum neck diameter in capillary break-up of simple liquids can be described by well-known self-similarity solutions, the pinching of non-Brownian suspension depends in a complex way on the particle dynamics in the thinning thread. Here we focus on the very dilute regime where the filament contains only isolated beads to identify the physical mechanisms leading to the pronounced acceleration of the filament thinning observed. This accelerated regime is characterized by an asymmetric shape of the filament with an enhanced curvature that depends on the size and the spatial distribution of the particles within the capillary thread.

  17. Measurement of Branching Fractions in Radiative BDecays to eta K gamma and Search for B Decays to eta' K gamma

    SciTech Connect

    Aubert, B.

    2006-03-31

    The authors present measurements of the B {yields} {eta}K{gamma} branching fractions and upper limits for the B {yields} {eta}'K{gamma} branching fractions. For B{sup +} {yields} {eta}K{sup +}{gamma} they also measure the time-integrated charge asymmetry. The data sample, collected with the BABAR detector at the Stanford Linear Accelerator Center, represents 232 x 10{sup 6} produced B{bar B} pairs. The results for branching fractions and upper limits at 90% C.L. in units of 10{sup -6} are: {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = 11.3{sub -2.6}{sup +2.8} {+-} 0.6, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = 10.0 {+-} 1.3 {+-} 0.5, {Beta}(B{sup 0} {yields} {eta}'K{sup 0}{gamma}) < 6.6, {Beta}(B{sup +} {yields} {eta}'K{sup +}{gamma}) < 4.2. The charge asymmetry in the decay B{sup +} {yields} {eta}K{sup +}{gamma} is {Alpha}{sub ch} = -0.09 {+-} 0.12 {+-} 0.01. The first errors are statistical and the second systematic.

  18. MOLECULES IN {eta} CARINAE

    SciTech Connect

    Loinard, Laurent; Menten, Karl M.; Guesten, Rolf; Zapata, Luis A.; Rodriguez, Luis F.

    2012-04-10

    We report the detection toward {eta} Carinae of six new molecules, CO, CN, HCO{sup +}, HCN, HNC, and N{sub 2}H{sup +}, and of two of their less abundant isotopic counterparts, {sup 13}CO and H{sup 13}CN. The line profiles are moderately broad ({approx}100 km s{sup -1}), indicating that the emission originates in the dense, possibly clumpy, central arcsecond of the Homunculus Nebula. Contrary to previous claims, CO and HCO{sup +} do not appear to be underabundant in {eta} Carinae. On the other hand, molecules containing nitrogen or the {sup 13}C isotope of carbon are overabundant by about one order of magnitude. This demonstrates that, together with the dust responsible for the dimming of {eta} Carinae following the Great Eruption, the molecules detected here must have formed in situ out of CNO-processed stellar material.

  19. Final Progress Report - Heavy Ion Accelerator Theory and Simulation

    SciTech Connect

    Haber, Irving

    2009-10-31

    The use of a beam of heavy ions to heat a target for the study of warm dense matter physics, high energy density physics, and ultimately to ignite an inertial fusion pellet, requires the achievement of beam intensities somewhat greater than have traditionally been obtained using conventional accelerator technology. The research program described here has substantially contributed to understanding the basic nonlinear intense-beam physics that is central to the attainment of the requisite intensities. Since it is very difficult to reverse intensity dilution, avoiding excessive dilution over the entire beam lifetime is necessary for achieving the required beam intensities on target. The central emphasis in this research has therefore been on understanding the nonlinear mechanisms that are responsible for intensity dilution and which generally occur when intense space-charge-dominated beams are not in detailed equilibrium with the external forces used to confine them. This is an important area of study because such lack of detailed equilibrium can be an unavoidable consequence of the beam manipulations such as acceleration, bunching, and focusing necessary to attain sufficient intensity on target. The primary tool employed in this effort has been the use of simulation, particularly the WARP code, in concert with experiment, to identify the nonlinear dynamical characteristics that are important in practical high intensity accelerators. This research has gradually made a transition from the study of idealized systems and comparisons with theory, to study the fundamental scaling of intensity dilution in intense beams, and more recently to explicit identification of the mechanisms relevant to actual experiments. This work consists of two categories; work in direct support beam physics directly applicable to NDCX and a larger effort to further the general understanding of space-charge-dominated beam physics.

  20. FERMI&Elettra Accelerator Technical Optimization Final Report

    SciTech Connect

    Cornacchia, M.; Craievich, P.; Di Mitri, S.; Pogorelov, I.; Qiang, J.; Venturini, M.; Zholents, A.; Wang, D.; Warnock, R.; /SLAC

    2007-04-30

    This chapter describes the accelerator physics aspects, the engineering considerations and the choice of parameters that led to the accelerator design of the FERMI Free-Electron-Laser. The accelerator (also called the ''electron beam delivery system'') covers the region from the exit of the injector to the entrance of the first FEL undulator. The considerations that led to the proposed configuration were made on the basis of a study that explored various options and performance limits. This work follows previous studies of x-ray FEL facilities (SLAC LCLS [1], DESY XFEL [2], PAL XFEL [3], MIT [4], BESSY FEL [5], LBNL LUX [6], Daresbury 4GLS [7]) and integrates many of the ideas that were developed there. Several issues specific to harmonic cascade FELs, and that had not yet been comprehensively studied, were also encountered and tackled. A particularly difficult issue was the need to meet the requirement for high peak current and small slice energy spread, as the specification for the ratio of these two parameters (that defines the peak brightness of the electron beam) is almost a factor of two higher than that of the LCLS's SASE FEL. Another challenging aspect was the demand to produce an electron beam with as uniform as possible peak current and energy distributions along the bunch, a condition that was met by introducing novel beam dynamics techniques. Part of the challenge was due to the fact that there were no readily available computational tools to carry out reliable calculations, and these had to be developed. Most of the information reported in this study is available in the form of scientific publications, and is partly reproduced here for the convenience of the reader.

  1. Quantum computing accelerator I/O : LDRD 52750 final report.

    SciTech Connect

    Schroeppel, Richard Crabtree; Modine, Normand Arthur; Ganti, Anand; Pierson, Lyndon George; Tigges, Christopher P.

    2003-12-01

    In a superposition of quantum states, a bit can be in both the states '0' and '1' at the same time. This feature of the quantum bit or qubit has no parallel in classical systems. Currently, quantum computers consisting of 4 to 7 qubits in a 'quantum computing register' have been built. Innovative algorithms suited to quantum computing are now beginning to emerge, applicable to sorting and cryptanalysis, and other applications. A framework for overcoming slightly inaccurate quantum gate interactions and for causing quantum states to survive interactions with surrounding environment is emerging, called quantum error correction. Thus there is the potential for rapid advances in this field. Although quantum information processing can be applied to secure communication links (quantum cryptography) and to crack conventional cryptosystems, the first few computing applications will likely involve a 'quantum computing accelerator' similar to a 'floating point arithmetic accelerator' interfaced to a conventional Von Neumann computer architecture. This research is to develop a roadmap for applying Sandia's capabilities to the solution of some of the problems associated with maintaining quantum information, and with getting data into and out of such a 'quantum computing accelerator'. We propose to focus this work on 'quantum I/O technologies' by applying quantum optics on semiconductor nanostructures to leverage Sandia's expertise in semiconductor microelectronic/photonic fabrication techniques, as well as its expertise in information theory, processing, and algorithms. The work will be guided by understanding of practical requirements of computing and communication architectures. This effort will incorporate ongoing collaboration between 9000, 6000 and 1000 and between junior and senior personnel. Follow-on work to fabricate and evaluate appropriate experimental nano/microstructures will be proposed as a result of this work.

  2. Advanced Klystrons for High Efficiency Accelerator Systems - Final Report

    SciTech Connect

    Read, Michael; Ives, Robert Lawrence

    2014-03-26

    This program explored tailoring of RF pulses used to drive accelerator cavities. Simulations indicated that properly shaping the pulse risetime to match accelerator cavity characteristics reduced reflected power and increased total efficiency. Tailoring the pulse requires a high power, gridded, klystron to shape the risetime while also controlling the beam current. The Phase I program generated a preliminary design of a gridded electron gun for a klystron producing 5-10 MW of RF power. This required design of a segmented cathode using Controlled Porosity Reservoir cathodes to limit power deposition on the grid. The program was successful in computationally designing a gun producing a high quality electron beam with grid control. Additional analysis of pulse tailoring indicated that technique would only be useful for cavity drive pulses that were less than approximately 2-3 times the risetime. Otherwise, the efficiency gained during the risetime of the pulse became insignificant when considering the efficiency over the entire pulse. Consequently, it was determined that a Phase II program would not provide sufficient return to justify the cost. Never the less, other applications for a high power gridded gun are currently being pursued. This klystron, for example, would facilitate development inverse Comptom x-ray sources by providing a high repetition rate (10 -100 kHz) RF source.

  3. Irradiation-Accelerated Corrosion of Reactor Core Materials. Final Report

    SciTech Connect

    Jiao, Zhujie; Was, Gary; Bartels, David

    2015-04-02

    This project aims to understand how radiation accelerates corrosion of reactor core materials. The combination of high temperature, chemically aggressive coolants, a high radiation flux and mechanical stress poses a major challenge for the life extension of current light water reactors, as well as the success of most all GenIV concepts. Of these four drivers, the combination of radiation and corrosion places the most severe demands on materials, for which an understanding of the fundamental science is simply absent. Only a few experiments have been conducted to understand how corrosion occurs under irradiation, yet the limited data indicates that the effect is large; irradiation causes order of magnitude increases in corrosion rates. Without a firm understanding of the mechanisms by which radiation and corrosion interact in film formation, growth, breakdown and repair, the extension of the current LWR fleet beyond 60 years and the success of advanced nuclear energy systems are questionable. The proposed work will address the process of irradiation-accelerated corrosion that is important to all current and advanced reactor designs, but remains very poorly understood. An improved understanding of the role of irradiation in the corrosion process will provide the community with the tools to develop predictive models for in-reactor corrosion, and to address specific, important forms of corrosion such as irradiation assisted stress corrosion cracking.

  4. [Advanced accelerator R and D program]. Final report

    SciTech Connect

    1997-12-31

    This proposal requests funding for a 3-year renewal of the DOE advanced accelerator R and D (AARD) program at Texas A and M University. The program to date has focused on the development of the gigatron, a compact high-efficiency microwave driver for future linear colliders. The author reports results and progress in that project, and plans to bring it to a milestone and conclusion by mid-1995. He proposes to initiate a second project, the development of a new technology for ultra-high field superconducting magnets for future hadron colliders. This project builds upon two magnet designs which he has introduced during the past year, which have the potential for a dramatic extension of the achievable field strength for both dipoles and quadrupoles.

  5. FERMI&Elettra Accelerator Technical Optimization FinalReport

    SciTech Connect

    Cornacchia, M.; Craievich, P.; Di Mitri, S.; Pogorelov, I.; Qiang, J.; Venturini, M.; Zholents, A.; Wang, D.; Warnock, R.

    2006-07-01

    This report describes the accelerator physics aspects, theengineering considerations and the choice of parameters that led to theaccelerator design of the FERMI Free-Electron-Laser. The accelerator(also called the "electron beam delivery system") covers the region fromthe exit of the injector to the entrance of the first FEL undulator. Theconsiderations that led to the proposed configuration were made on thebasis of a study that explored various options and performance limits.This work follows previous studies of x-ray FEL facilities (SLAC LCLS[1], DESY XFEL [2], PAL XFEL [3], MIT [4], BESSY FEL[5], LBNL LUX [6],Daresbury 4GLS [7]) and integrates many of the ideas that were developedthere. Several issues specific to harmonic cascade FELs, and that had notyet been comprehensively studied, were also encountered and tackled. Aparticularly difficult issue was the need to meet the requirement forhigh peak current and small slice energy spread, as the specification forthe ratio of these two parameters (that defines the peak brightness ofthe electron beam) is almost a factor of two higher than that of theLCLS's SASE FEL. Another challenging aspect was the demand to produce anelectron beam with as uniform as possible peak current and energydistributions along the bunch, a condition that was met by introducingnovel beam dynamics techniques. Part of the challenge was due to the factthat there were no readily available computational tools to carry outreliable calculations, and these had to be developed. Most of theinformation reported in this study is available in the form of scientificpublications, and is partly reproduced here for the convenience of thereader.

  6. Accelerator development for the NRL (Naval Research Laboratory) free-electron-laser program. Final report, July 1981-April 1986

    SciTech Connect

    Lucey, R.; Putnam, S.

    1988-06-01

    Included in the report are descriptions of the final assembly and operation of the Linear Induction Accelerator(LIA), installation and testing of a new accelerating gap in the five-core stage of the accelerator to operate at 150 kV, and the moving of and modifications of the charging and firing controls for remote operation of the accelerator.

  7. Final Report for "Community Petascale Project for Accelerator Science and Simulations".

    SciTech Connect

    Cary, J. R.; Bruhwiler, D. L.; Stoltz, P. H.; Cormier-Michel, E.; Cowan, B.; Schwartz, B. T.; Bell, G.; Paul, K.; Veitzer, S.

    2013-04-19

    This final report describes the work that has been accomplished over the past 5 years under the Community Petascale Project for Accelerator and Simulations (ComPASS) at Tech-X Corporation. Tech-X had been involved in the full range of ComPASS activities with simulation of laser plasma accelerator concepts, mainly in collaboration with LOASIS program at LBNL, simulation of coherent electron cooling in collaboration with BNL, modeling of electron clouds in high intensity accelerators, in collaboration with researchers at Fermilab and accurate modeling of superconducting RF cavity in collaboration with Fermilab, JLab and Cockcroft Institute in the UK.

  8. Measurements of Branching Fraction and CP Violation inB Meson Rare Decays to Final States containing eta or eta' Mesons in the BaBar Experiment at SLAC

    SciTech Connect

    Lazzaro, Alfio

    2007-04-11

    Note that the main goal of this thesis work is the measurement of the branching fractions, charge asymmetry, and Time-Dependent CP Violation in η'K0 mode. All other measurements are reported here for completion because they are connected by similar physics arguments. They are part of the Milan analysis activity, done by undergraduate students. They should not be considered as done in this thesis work. The measurements of the two body-modes ηη, ηΦ, and η'Φare used to determine a theoretical bound based on SU(3) flavor symmetry for the difference between SM prediction and the experimental measurements of CP violation parameters in b → s loop-dominated modes. In general for this estimation we need to measure the branching fractions (or upper limits) of neutral B decays to two-body modes with η', η, Φ, ω, π0, K0, K*0 [13, 14, 15, 16]. There is an important issue related to the branching fractions of η'K (charged and neutral) modes. Since the discover of B → η'K in 1997 [17] with high branching fraction (higher than expected), it was found that the corresponding mode with η is suppressed. This fact was pointed out by Lipkin in 1991 [18]. In particular, using arguments concerning the η-η' mixing angle and the parity of K or K* we can say that η'K and vK* are enhanced, while ηK and η'K* are suppressed. This scheme is experimentally verified. The branching fraction of all these modes are already measured, but the B0 → ηK0. So it is important to measure also this mode to complete the scenario. Finally we report on the measurements of the radiative modes B → η'Kγ and of the three-body mode B → η'η'K. Both cases are good candidates to manifest effects due to NP in CP violations [19, 20]. For all measurements we use an unbinned maximum likelihood fit to extract the number of signal yields and CP parameters. To perform these fits we have developed a flexible program in C

  9. The Uncloaking of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.

    2000-01-01

    Space Telescope Imaging Spectrograph spectroscopy has revealed much new detail of the ejecta thrown out of Eta Carinae. We have now accomplished eight visits of the star and the Homunculus using the STIS with a 52" x 0.1" aperture and with spectral coverage from 1640A to 10400A. Moreover we now have FUV observations with the STIS and with FUSE. From the FUSE and FUV observations, we see strong evidence for a hot companion star, likely in agreement with the binaricity of the spectrum in the near red. From the STIS observations, we see evidence of much substructure of the ejecta, ranging from the fast moving strings noted by Kirstin Weis, the outer emission nebula, to the Homunculus lobes and a disk. Deep within, we find a bipolar structure, the Integral Nebula and finally close to the star, a small ionized gas region that shows evidence of the stellar wind being resolved from the central source(s).

  10. Search for B^0 meson decays to \\pi^0 K^0_S K^0_S, \\eta K^0_S K^0_S, and \\eta^{\\prime}K^0_S K^0_S

    SciTech Connect

    Aubert, B.

    2009-05-08

    We describe searches for B{sup 0} meson decays to the charmless final states {pi}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}, {eta}K{sub S}{sup 0}K{sub S}{sup 0}, and {eta}{prime}K{sub S}{sup 0}K{sub S}{sup 0}. The data sample corresponds to 467 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation and collected with the BABAR detector at the SLAC National Accelerator Laboratory. We find no significant signals and determine the 90% confidence level upper limits on the branching fractions, in units of 10{sup -7}, {Beta}(B{sup 0} {yields} {pi}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}) < 12, {Beta}(B{sup 0} {yields} {eta}K{sub S}{sup 0}K{sub S}{sup 0}) < 10, and {Beta}(B{sup 0} {yields} {eta}{prime}K{sub S}{sup 0}K{sub S}{sup 0}) < 20.

  11. Study of B meson decays with excited eta and eta' mesons.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Karyotakis, Y; Lees, J P; Poireau, V; Prudent, X; Tisserand, V; Zghiche, A; Tico, J Garra; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Wenzel, W A; del Amo Sanchez, P; Hawkes, C M; Watson, A T; Held, T; Koch, H; Pelizaeus, M; Schroeder, T; Steinke, M; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Saleem, M; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Liu, F; Long, O; Shen, B C; Zhang, L; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wilson, M G; Winstrom, L O; Chen, E; Cheng, C H; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Gabareen, A M; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Klose, V; Kobel, M J; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Lombardo, V; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Watson, J E; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Santoro, V; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Dauncey, P D; Flack, R L; Nash, J A; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Zheng, Y; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Fabozzi, F; Lista, L; Monorchio, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; LoSecco, J M; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gagliardi, N; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Leruste, Ph; Malclès, J; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cenci, R; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Biesiada, J; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Baracchini, E; Bellini, F; Cavoto, G; del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Castelli, G; Franek, B; Olaiya, E O; Ricciardi, S; Roethel, W; Wilson, F F; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Hryn'ova, T; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Hollar, J J; Kutter, P E; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Neal, H

    2008-08-29

    Using 383 x 10(6) BBover pairs from the BABAR data sample, we report results for branching fractions of six charged B-meson decay modes, where a charged kaon recoils against a charmless resonance decaying to KKover* or etapipi final states with mass in the range (1.2-1.8) GeV/c2. We observe a significant enhancement at the low KKover* invariant mass which is interpreted as B+-->eta(1475)K+, find evidence for the decay B+-->eta(1295)K+, and place upper limits on the decays B+-->eta(1405)K+, B+-->f1(1285)K+, B+-->f1(1420)K+, and B+-->phi(1680)K+. PMID:18851601

  12. Physics Design of the Eta-II Double Pulse Target Experiment

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Jiuan; Ho, Darwin D.-H.; McCarrick, James; Paul, Arthur; Sampayan, Stephen; Wang, Li-Fang; Weir, John

    2000-10-01

    The second-axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility will provide four 2.1 mm spot size, x-ray pulses within 2 ms with their x-doses in the range of several hundred rads at a meter for x-ray imaging. To achieve its performance specifications, there should be a sufficient amount of the DARHT-II x-ray converter material remaining while it turns into plasma and expands rapidly due to the heating of previous beam pulses. Furthermore, the beam-target interactions, such as the unwanted focusing by the backstreaming ions from the desorbed gas from the target surface for the first pulse and by those from the target plasma for the subsequent pulses, and the instability of the beam propagating in dense plasma, should be mitigated. We have modified the single pulse target experimental facility on the Experimental Test Accelerator II (ETA-II) to perform the double pulse target experiments to validate the DARHT-II multi-pulse target concept. The 1.15 MeV, 2 kA Snowtron injector will be used to provide the first electron pulse. The 6 MeV, 2 kA ETA-II beam will be used as the probe beam, i.e., the second pulse. The ETA-II target is located inside a focusing magnet (near the center). To use the same ETA-II final focus lens, an iron sleeve will be inserted from the downstream side of the magnet to reduce the downstream side’s magnetic field, and the Snowtron beam will strike the x-ray converter from the back. The physics design of the final focus area will be presented. We have modeled the hydrodynamics of the target expansion for the Snowtron beam. Comparison against the DARHT-II target will be presented.

  13. Evidence for the eta_b(1S) in the Decay Upsilon(2S)-> gamma eta_b(1S)

    SciTech Connect

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Karlsruhe U., EKP /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2009-12-14

    We have performed a search for the {eta}{sub b}(1S) meson in the radiative decay of the {Upsilon}(2S) resonance using a sample of 91.6 million {Upsilon}(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at E{sub {gamma}} = 610.5{sub -4.3}{sup +4.5}(stat) {+-} 1.8(syst) MeV, corresponding to an {eta}{sub b}(1S) mass of 9392.9{sub -4.8}{sup +4.6}(stat) {+-} 1.9(syst) MeV/c{sup 2}. The branching fraction for the decay {Upsilon}(2S) {yields} {gamma}{eta}{sub b}(1S) is determined to be (4.2{sub -1.0}{sup +1.1}(stat) {+-} 0.9(syst)) x 10{sup -4}. The ratio {Beta}({Upsilon}(2S) {yields} {gamma}{eta}{sub b}(1S))/{Beta}({Upsilon}(3S) {yields} {gamma}{eta}{sub b}(1S)) = 0.89{sub -0.23}{sup +0.25}(stat){sub -0.16}{sup +0.12}(syst) is consistent with the ratio expected for magnetic dipole transitions to the {eta}{sub b}(1S) meson.

  14. Summary of the [eta]-meson sessions

    SciTech Connect

    Chrien, R.E.

    1993-01-01

    This summary describes the contents of the nineteen talks related to research on the [eta] meson and presented at the Workshop of Future Directions. The subjects of this area include threshold [eta] production, [eta]-nuclear spectroscopy, baryon spectroscopy, [eta] decays, facilities, and instrumentation.

  15. Summary of the {eta}-meson sessions

    SciTech Connect

    Chrien, R.E.

    1993-06-01

    This summary describes the contents of the nineteen talks related to research on the {eta} meson and presented at the Workshop of Future Directions. The subjects of this area include threshold {eta} production, {eta}-nuclear spectroscopy, baryon spectroscopy, {eta} decays, facilities, and instrumentation.

  16. The seismology of eta Bootes

    NASA Technical Reports Server (NTRS)

    Demarque, Pierre; Guenther, D. B.

    1995-01-01

    Some p-mode frequencies and other observations were used to determine the mass, the age and the helium abundance of eta Bootes. It is shown how, by direct application, the p-mode frequencies and stellar seismological tools help in constraining the physical parameters of eta Boo. The existence of mode bumping is confirmed and it is discussed how it may be used to refine the estimate of the eta Boo's age. The effect of the OPAL equation of state on the p-mode frequencies is described.

  17. Constraints on Decreases in Eta Carinae's Mass-loss from 3D Hydrodynamic Simulations of Its Binary Colliding Winds

    NASA Technical Reports Server (NTRS)

    Madura, T. I.; Gull, T. R.; Okazaki, A. T.; Russell, C. M. P.; Owocki, S. P.; Groh, J. H.; Corcoran, M. F.; Hamaguchi, K.; Teodoro, M.

    2013-01-01

    Recent work suggests that the mass-loss rate of the primary star Eta-A in the massive colliding wind binary Eta Carinae dropped by a factor of 2-3 between 1999 and 2010. We present result from large- (+/- 1545 au) and small- (+/- 155 au) domain, 3D smoothed particle hydrodynamics (SPH) simulations of Eta Car's colliding winds for three Eta-A mass-loss rates ( (dot-M(sub Eta-A) = 2.4, 4.8 and 8.5 × 10(exp -4) M(solar)/ yr), investigating the effects on the dynamics of the binary wind-wind collision (WWC). These simulations include orbital motion, optically thin radiative cooling and radiative forces. We find that dot-M Eta-A greatly affects the time-dependent hydrodynamics at all spatial scales investigated. The simulations also show that the post-shock wind of the companion star Eta-B switches from the adiabatic to the radiative-cooling regime during periastron passage (Phi approx.= 0.985-1.02). This switchover starts later and ends earlier the lower the value of dot-M Eta-A and is caused by the encroachment of the wind of Eta-A into the acceleration zone of Eta-B's wind, plus radiative inhibition of Eta-B's wind by Eta-A. The SPH simulations together with 1D radiative transfer models of Eta-A's spectra reveal that a factor of 2 or more drop in dot-M EtaA should lead to substantial changes in numerous multiwavelength observables. Recent observations are not fully consistent with the model predictions, indicating that any drop in dot- M Eta-A was likely by a factor of approx. < 2 and occurred after 2004. We speculate that most of the recent observed changes in Eta Car are due to a small increase in the WWC opening angle that produces significant effects because our line of sight to the system lies close to the dense walls of the WWC zone. A modest decrease in dot-M Eta-A may be responsible, but changes in the wind/stellar parameter of Eta-B, while less likely, cannot yet be fully ruled out. We suggest observations during Eta-Car's next periastron in 2014 to further

  18. A Non-scaling Fixed Field Alternating Gradient Accelerator for the Final Acceleration Stage of the International Design Study of the Neutrino Factory.

    SciTech Connect

    Berg, J.S.; Aslaninejad, M.; Pasternak, J.; Witte, H.; Bliss, N. Cordwell M.; Jones, T.; Muir, A., Kelliher, D.; Machida, S.

    2011-09-04

    The International Design Study of the Neutrino Factory (IDS-NF) has recently completed its Interim Design Report (IDR), which presents our current baseline design of the neutrino factory. To increase the efficiency and reduce the cost of acceleration, the IDR design uses a linear non-scaling fixed field alternating gradient accelerator (FFAG) for its final acceleration stage. We present the current lattice design of that FFAG, including the main ring plus its injection and extraction systems. We describe parameters for the main ring magnets, kickers, and septa, as well as the power supplies for the kickers. We present a first pass at an engineering layout for the ring and its subsystems.

  19. Observation of B0-->omega K0, B+-->eta pi+, and B+-->eta K+ and study of related decays.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Watson, N K; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmuecker, H; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Mackay, C; Wilson, F F; Abe, K; Cuhadar-Donszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Teodorescu, L; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Gary, J W; Layter, J; Shen, B C; Wang, K; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Beringer, J; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Erwin, R J; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Lee, C L; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, J; Schubert, K R; Schwierz, R; Spaan, B; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Khan, A; Lavin, D; Muheim, F; Playfer, S; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Grenier, G J; Lee, S-J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Brigljević, V; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, E; Gamet, R; Kay, M; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Cote-Ahern, D; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; John, M J J; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Del Gamba, V; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lu, C; Miftakov, V; Olsen, J; Smith, A J S; Varnes, E W; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yeche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Convery, M R; Cristinziani, M; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Elsen, E E; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Johnson, J R; Kutter, P E; Li, H; Liu, R; Di Lodovico, F; Mihalyi, A; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Neal, H

    2004-02-13

    We present measurements of branching fractions and charge asymmetries for seven B-meson decays with an eta, eta', or omega meson in the final state. The data sample corresponds to 89x10(6) BB pairs produced from e(+)e(-) annihilation at the Upsilon(4S) resonance. We measure the following branching fractions in units of 10(-6): B(B+-->eta pi(+))=5.3+/-1.0+/-0.3, B(B+-->eta K+)=3.4+/-0.8+/-0.2, B(B0-->eta K0)=2.9+/-1.0+/-0.2 (<5.2, 90% C.L.), B(B+-->eta(')pi(+))=2.7+/-1.2+/-0.3 (<4.5, 90% C.L.), B(B+-->omega pi(+))=5.5+/-0.9+/-0.5, B(B+-->omega K+)=4.8+/-0.8+/-0.4, and B(B0-->omega K0)=5.9(+1.6)(-1.3)+/-0.5. The charge asymmetries are A(ch)(B+-->eta pi(+))=-0.44+/-0.18+/-0.01, A(ch)(B+-->eta K+)=-0.52+/-0.24+/-0.01, A(ch)(B+-->omega pi(+))=0.03+/-0.16+/-0.01, and A(ch)(B+-->omega K+)=-0.09+/-0.17+/-0.01. PMID:14995230

  20. Final Report to the Department of Energy on the 1994 International Accelerator School: Frontiers of Accelerator Technology

    SciTech Connect

    Harris, F.A.

    1998-09-17

    The international accelerator school on Frontiers of Accelerator Technology was organized jointly by the US Particle Accelerator School (Dr. Mel Month and Ms. Marilyn Paul), the CERN Accelerator School, and the KEK Accelerator School, and was hosted by the University of Hawaii. The course was held on Maui, Hawaii, November 3-9, 1994 and was made possible in part by a grant from the Department of Energy under award number DE-FG03-94ER40875, AMDT M006. The 1994 program was preceded by similar joint efforts held at Santa Margherita di Pula, Sardinia in February 1985, South Padre Island, Texas in October 1986, Anacapri, Italy in October 1988, Hilton Head Island, South Carolina in October 1990, and Benalmedena, Spain in October/November 1992. The most recent program was held in Montreux, Switzerland in May 1998. The purpose of the program is to disseminate knowledge on the latest ideas and developments in the technology of particle accelerators by bringing together known world experts and younger scientists in the field. It is intended for individuals with professional interest in accelerator physics and technology, for graduate students, for post-docs, for those interested in accelerator based sciences, and for scientific and engineering staff at industrial firms, especially those companies specializing in accelerator components.

  1. Ultraviolet and visual wavelength spectroscopy of gas around ETA Carinae

    NASA Technical Reports Server (NTRS)

    Davidson, K.; Dufour, R. J.; Walborn, N. R.; Gull, T. R.

    1986-01-01

    Observational results of Eta Carinae are reported, especially spectroscopy of the outer 'S condensation' supplemented by data on the homunculus and its core. Theoretical calculations of atmosphere/wind models and of the shock-heated S condensation are needed for a proper analysis of the data, but some simplified results are discussed. The helium abundance at the surface of Eta Car appears to be roughly 0.4, and most of the CNO is nitrogen. There does not appear to be any reason, at present, to alter the often quoted temperature estimate of 30,000 K for the radiating surface (which may or may not be the surface of the star itself). The presently observed mass loss rate is probably less than 10 exp -2.4 solar masses/yr if the outflow is not strongly direction-dependent. Finally, a largely forgotten but highly relevant historical conjecture concerning Eta Car is mentioned.

  2. eta Carinae Continues to Evolve (Abstract)

    NASA Astrophysics Data System (ADS)

    Martin, J. C.

    2015-06-01

    (Abstract only) Eta Carinae affords us a unique opportunity to study the pre-supernova evolution of the most massive stars. For at least the last half century, it has maintained a 5.5-year spectroscopic cycle that culminates with abrupt decreases in the strong stellar wind emission features. Over the last 15 years, the star has brightened at an accelerated rate and altered its spectrum, in addition to the spectroscopic cycle, indicating an ongoing change in state. We present Hubble Space Telescope spectroscopy and synthetic photometry from the most recent spectroscopic event (2014.5) that shows notable differences with past events and provides clues to the on-going evolution of the star.

  3. All Pillars Point to Eta

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Eta Carinae Starforming RegionSimulated Infrared View of Comet Tempel 1 (artist's concept)

    These false-color image taken by NASA's Spitzer Space Telescope shows the 'South Pillar' region of the star-forming region called the Carina Nebula. Like cracking open a watermelon and finding its seeds, the infrared telescope 'busted open' this murky cloud to reveal star embryos (yellow or white) tucked inside finger-like pillars of thick dust (pink). Hot gases are green and foreground stars are blue. Not all of the newfound star embryos can be easily spotted.

    Though the nebula's most famous and massive star, Eta Carinae, is too bright to be observed by infrared telescopes, the downward-streaming rays hint at its presence above the picture frame. Ultraviolet radiation and stellar winds from Eta Carinae and its siblings have shredded the cloud to pieces, leaving a mess of tendrils and pillars. This shredding process triggered the birth of the new stars uncovered by Spitzer.

    The inset visible-light picture (figure 2) of the Carina Nebula shows quite a different view. Dust pillars are fewer and appear dark because the dust is soaking up visible light. Spitzer's infrared detectors cut through this dust, allowing it to see the heat from warm, embedded star embryos, as well as deeper, more buried pillars. The visible-light picture is from the National Optical Astronomy Observatory.

    Eta Carina is a behemoth of a star, with more than 100 times the mass of our Sun. It is so massive that it can barely hold itself together. Over the years, it has brightened and faded as material has shot away from its surface. Some astronomers think Eta Carinae might die in a supernova blast within our lifetime.

    Eta Carina's home, the Carina Nebula, is located in the southern portion of our Milky Way galaxy, 10,000 light-years from Earth. This colossal cloud of gas and dust

  4. Intercampus institute for research at particle accelerators. Final report, March 15, 1992--September 30, 1995

    SciTech Connect

    1997-09-22

    This is the final report to the DOE for the Intercampus Institute for Research at Particle Accelerators, or IIRPA, at least for the San Diego branch. Over the years that DOE supported IIRPA, we were told that yearly reports (and the final report) were not necessary because the previous year`s summary in our annual request for funds constituted those reports. Therefore, it has taken some effort, and a corresponding long time, to put something together, after the fact. The IIRPA was born as an idea that arose during discussions at the 1974 PEP summer study, and began to be funded by DoE during the early stages of PEP detector design and construction. The intent was for the members of the Institute to be responsible for the PEP-9 Facility; all of the PEP experiments were supposed to be facilities, rather than just experimental setups for a particular group or research goal. IIRPA was approved as a Multicampus Research Unit (MRU) in 1977 by the University of California, and it was active on the UCD, UCSB and UCSD campuses for 10 years. This report concentrates on the period of time when the Directorship of IIRPA was once again at the San Diego campus, 1989 to 1995. The collection of yearly reports consisting of research in different areas of particle physics, make up this report in the appendices.

  5. Rare semileptonic B{sub s} decays to {eta} and {eta}' mesons in QCD

    SciTech Connect

    Azizi, K.; Khosravi, R.; Falahati, F.

    2010-12-01

    We analyze the rare semileptonic B{sub s}{yields}({eta},{eta}{sup '})l{sup +}l{sup -}, (l=e,{mu},{tau}), and B{sub s}{yields}({eta},{eta}{sup '}){nu}{nu} transitions probing the ss content of the {eta} and {eta}{sup '} mesons via three-point QCD sum rules. We calculate responsible form factors for these transitions in full theory. Using the obtained form factors, we also estimate the related branching fractions and longitudinal lepton polarization asymmetries. Our results are in a good consistency with the predictions of the other existing nonperturbative approaches.

  6. UCLA Final Technical Report for the "Community Petascale Project for Accelerator Science and Simulation”.

    SciTech Connect

    Mori, Warren

    2015-08-14

    The UCLA Plasma Simulation Group is a major partner of the “Community Petascale Project for Accelerator Science and Simulation”. This is the final technical report. We include an overall summary, a list of publications, progress for the most recent year, and individual progress reports for each year. We have made tremendous progress during the three years. SciDAC funds have contributed to the development of a large number of skeleton codes that illustrate how to write PIC codes with a hierarchy of parallelism. These codes cover 2D and 3D as well as electrostatic solvers (which are used in beam dynamics codes and quasi-static codes) and electromagnetic solvers (which are used in plasma based accelerator codes). We also used these ideas to develop a GPU enabled version of OSIRIS. SciDAC funds were also contributed to the development of strategies to eliminate the Numerical Cerenkov Instability (NCI) which is an issue when carrying laser wakefield accelerator (LWFA) simulations in a boosted frame and when quantifying the emittance and energy spread of self-injected electron beams. This work included the development of a new code called UPIC-EMMA which is an FFT based electromagnetic PIC code and to new hybrid algorithms in OSIRIS. A new hybrid (PIC in r-z and gridless in φ) algorithm was implemented into OSIRIS. In this algorithm the fields and current are expanded into azimuthal harmonics and the complex amplitude for each harmonic is calculated separately. The contributions from each harmonic are summed and then used to push the particles. This algorithm permits modeling plasma based acceleration with some 3D effects but with the computational load of an 2D r-z PIC code. We developed a rigorously charge conserving current deposit for this algorithm. Very recently, we made progress in combining the speed up from the quasi-3D algorithm with that from the Lorentz boosted frame. SciDAC funds also contributed to the improvement and speed up of the quasi-static PIC

  7. Recent results on eta and eta-prime photoproduction on the proton

    SciTech Connect

    Barry Ritchie

    2004-06-01

    The experimental situation on eta and eta' photoproduction on the proton is reviewed, emphasizing progress made since 2001. New preliminary results for eta' photoproduction on the proton from Jefferson Lab are presented. Experimental results are compared with several theoretical approaches, with an emphasis on consequences for understanding baryon spectroscopy.

  8. Recirculation acceleration of high current relativistic electron beams--a feasibility study. Final report

    SciTech Connect

    Wilson, M.

    1981-06-01

    One of the advanced accelerator concepts under study at NBS involves multiplying the energy gained by a long-pulse, high current relativistic electron beam by directing the beam several times through the same induction accelerator during the time of one voltage pulse. Should this concept of the recirculation acceleration of intense electron beams be proven feasible, the savings in cost, size, and weight of a high current accelerator would be considerable. Energy gain by recirculation acceleration through a small-scale proof-of principle facility has been demonstrated at NBS. The study employs a 750A, 750keV electron beam pulse, 2 microsec long, generated by a linear induction accelerator of unique design which was also developed at NBS.

  9. A Framework for a General Purpose Intelligent Control System for Particle Accelerators. Phase II Final Report

    SciTech Connect

    Dr. Robert Westervelt; Dr. William Klein; Dr. Michael Kroupa; Eric Olsson; Rick Rothrock

    1999-06-28

    Vista Control Systems, Inc. has developed a portable system for intelligent accelerator control. The design is general in scope and is thus configurable to a wide range of accelerator facilities and control problems. The control system employs a multi-layer organization in which knowledge-based decision making is used to dynamically configure lower level optimization and control algorithms.

  10. Final Report for "Modeling Electron Cloud Diagnostics for High-Intensity Proton Accelerators"

    SciTech Connect

    Seth A Veitzer

    2009-09-25

    Electron clouds in accelerators such as the ILC degrade beam quality and limit operating efficiency. The need to mitigate electron clouds has a direct impact on the design and operation of these accelerators, translating into increased cost and reduced performance. Diagnostic techniques for measuring electron clouds in accelerating cavities are needed to provide an assessment of electron cloud evolution and mitigation. Accurate numerical modeling of these diagnostics is needed to validate the experimental techniques. In this Phase I, we developed detailed numerical models of microwave propagation through electron clouds in accelerating cavities with geometries relevant to existing and future high-intensity proton accelerators such as Project X and the ILC. Our numerical techniques and simulation results from the Phase I showed that there was a high probability of success in measuring both the evolution of electron clouds and the effects of non-uniform electron density distributions in Phase II.

  11. Resolving Eta Carinae and It's Ejecta

    NASA Technical Reports Server (NTRS)

    Gull Theodore R.; Oegerle, William R. (Technical Monitor)

    2002-01-01

    Imaging spectroscopy of Eta Carinae and the Homunculus has led to considerable new insight on the excitation mechanisms, the elemental abundances, and the physical properties of ejecta from Eta Carinae. With HST/STIS we have been able to resolve the central source into many substructures.

  12. Eta Carinae: an Astrophysical Laboratory

    NASA Astrophysics Data System (ADS)

    Nielsen, Krister E.; Gull, Theodore R.

    2009-05-01

    Eta Carinae provides a unique example to investigate a massive star in a late evolutionary phase and how CNO-processed material is ejected and mixed with the interstellar medium. The absorbing gas surrounding Eta Carinae (η Car) shows similar characteristics to the intervening gas in spectra of gamma ray burst progenitors. Consequently, the η Car spectrum may provide clues about the nature of other extreme objects such as hypernovae and supernova impostors. In the 1840s, η Car underwent a massive ejection, which was repeated to a lesser extent in the 1890s. Today we see the Homunculus, a bipolar expanding neutral shell, and the Little Homunculus, an interior, spectroscopically time-variable, ionized structure. The η Car system is ideal as a laboratory for absorption and emission line spectroscopy. In the line-of-sight towards η Car, multiple narrow absorption lines are observed from environments with densities around 107 cm- 3 and temperatures ranging from 60 to 7000 K. Thousands of neutral/singly ionized metal lines are identified, in addition to molecular lines in species such as H2, CH, OH and NH. The input from the laboratory spectroscopy community has furthered the analysis of η Car. Future observations of η Car in the infrared through radio wavelength region will enable new detections of atomic and molecular transitions, most notably of hydrides and nitrides. We will demonstrate how experimentally derived atomic data have improved our spectral analysis, and illuminate where future work is needed.

  13. The Enigmatic Eta Carinae: Current Status

    NASA Astrophysics Data System (ADS)

    Hillier, D. J.

    2008-06-01

    Eta Carinae is one of the most famous Luminous Blue Variables but also one of the least understood. Our understanding of η Carinae is severely hindered by the dense wind of the primary star, the influence of a binary companion, the complex circumstellar environment, the asymmetric nature of the mass loss, and the presence of an ``intrinsic" coronagraph which biases our view of Eta Carinae. With the advent of extensive new Hubble Space Telescope data, X-ray data, and ground-based spectroscopic and interferometric observations of Eta Carinae, there has been a dramatic increase in observational material which can be used to place constraints on Eta Carinae and its Homunculus. We summarize recent results, and highlight how recent data is providing new insight into the nature of Eta Carinae.

  14. Development of a two-beam high-current ion accelerator based on Doppler effect. Final report (1994)

    SciTech Connect

    Ivanov, B.I.; Yegorov, A.M.

    1995-03-01

    This Final Report presents the results of work accomplished in accordance with the Scope of Work to the Purchase Order No 4596310. The amount of works includes the following items: 1. Start of the manufacture of the Experimental Accelerating Stand (EAS)-the section for proton acceleration from 5 MeV to 8 MeV, in which RF fields are excited by an electron beam at the anomalous Doppler effect. 2. Theoretical investigation and computer simulation of field excitation and ion acceleration in the EAS. Under item 1, the EAS manufacturing is begun. To present time, a pedestal for the EAS and a stainless steel vacuum chamber for RF resonator are made (length of the chamber is about 180 cm, diameter is about 40 cm). Besides, parts of the EAS resonator with the acceleration structure are manufactured, and its assembly is begun. Under item 2, it is realized three works: calculation of increment and frequency shift of the EAS resonator excited by electron beam, calculation of the solenoid for creation of magnetic field with required spatial distribution, and theoretical investigation and computer simulation of ion acceleration in the EAS. 14 figs., 16 refs.

  15. Dilution jets in accelerated cross flows. Ph.D. Thesis Final Report

    NASA Technical Reports Server (NTRS)

    Lipshitz, A.; Greber, I.

    1984-01-01

    Results of flow visualization experiments and measurements of the temperature field produced by a single jet and a row of dilution jets issued into a reverse flow combustor are presented. The flow in such combustors is typified by transverse and longitudinal acceleration during the passage through its bending section. The flow visualization experiments are designed to examine the separate effects of longitudinal and transverse acceleration on the jet trajectory and spreading rate. A model describing a dense single jet in a lighter accelerating cross flow is developed. The model is based on integral conservation equations, including the pressure terms appropriate to accelerating flows. It uses a modified entrainment correlation obtained from previous experiments of a jet in a cross stream. The flow visualization results are compared with the model calculations in terms of trajectories and spreading rates. Each experiment is typified by a set of three parameters: momentum ratio, density ratio and the densimetric Froude number.

  16. Pseudoscalar glueball and {eta}-{eta}{sup '} mixing

    SciTech Connect

    Mathieu, Vincent; Vento, Vicente

    2010-02-01

    We have performed a dynamical analysis of the mixing in the pseudoscalar channel with the goal of understanding the existence and behavior of the pseudoscalar glueball. Our philosophy has not been to predict precise values of the glueball mass but to exploit an adequate effective theory to the point of breaking and to analyze which kind of mechanisms restore compatibility with data. Our study has led to analytical solutions which allow a clear understanding of the phenomena. The outcome of our calculation leads to a large mass glueball M{sub {Theta}>}2000 MeV, to a large glue content of the {eta}{sup '}, and to mixing angles in agreement with previous numerical studies.

  17. Eta Carinae: A Demanding Mistress

    NASA Technical Reports Server (NTRS)

    Gull, Theodore

    2012-01-01

    In the 1840's a southern star, Eta Argus, brightened to rival Sirius for nearly a decade, then faded. Today, we see the Homunculus, an hourglass figure with tutu, a dusty shell exceeding 12 solar masses expanding outward at 500 km/s. Many observers have systematically studied the massive binary total shrouded by interacting winds and its ejecta. More recently 3-D wind-wind collision models have begun to explain the extended structures resolved by Hubble Space Telescope. Now Herschel Space Observatory infrared scans are revealing wind interaction emissions and complex molecules left over from the dust that formed out of gas originally overabundant in nitrogen and greatly-depleted in oxygen and carbon. Many questions remain to be answered: What is the dust that formed in the 1840s event? What are the end states of the two massive companions ... SN, GRB, Hypernova? and When

  18. ETA-II experiments for determining advanced radiographic capabilities of induction linacs

    SciTech Connect

    Weir, J.T.; Caporaso, G.J.; Clark, J.C.; Kirbie, H.C.; Chen, Y.-J.; Lund, S.M.; Westenskow, G.A.; Paul, A.C

    1997-05-01

    LLNL has proposed a multi-pulsed, multi-line of sight radiographic machine based on induction linac technology to be the core of the advanced hydrotest facility (AHF) being considered by the Department of Energy. In order to test the new technologies being developed for AHF we have recommissioned the Experimental Test Accelerator (ETA II). We will conduct our initial experiments using kickers and large angle bending optics at the ETA II facility. Our current status and our proposed experimental schedule will be presented.

  19. Collective acceleration of electrons and ions in a high current relativistic electron beam. Final report

    SciTech Connect

    Nation, J.A.

    1996-12-31

    The original purpose of this research was an investigation into the use of slow space charge waves on weakly relativistic electron beams for ion acceleration. The work had three main objectives namely, the development of a suitable ion injector, the growth and study of the properties of slow space charge waves on an electron beam, and a combination of the two components parts into a suitable proof of principle demonstration of the wave accelerator. This work focusses on the first two of these objectives.

  20. Phenomenology of some rare and forbidden. eta. -decays

    SciTech Connect

    Herczeg, P.

    1990-01-01

    We discuss the contribution from possible new physics to the decays {eta} {yields} {mu}{sup +}{mu}{sup {minus}}, {eta} {yields} e{sup +}e{sup {minus}}, {eta} {yields} {mu}e and {eta} {pi}{mu}e, and assess the sensitivities required for experimental studies of these decays to extend our knowledge about the new interactions. 61 refs.

  1. THE ENVIRONMENTAL TECHNOLOGIES ACCEPTANCE (ETA) PROGRAM

    SciTech Connect

    Christina B. Behr-Andres

    2001-04-01

    The Environmental Technologies Acceptance (ETA) Program at the Energy and Environmental Research Center (EERC) is intended to advance the development, commercial acceptance, and timely deployment of selected private sector technologies for the cleanup of sites in the nuclear defense complex as well as the greater market. As shown in Table 1, this cooperative agreement funded by the National Energy Technology Laboratory (NETL) consists of three tasks: Technology Selection, Technology Development, and Technology Verification. As currently conceived, the ETA will address the needs of as many technologies as appropriate under its current 3-year term. This report covers activities during the first 6 months of the 3-year ETA program.

  2. Eta Carinae and Its Ejecta, the Homunculus

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.

    2014-01-01

    Eta Carinae (Eta Car), its interacting winds and historical ejecta provide an unique astrophysical laboratory that permits addressing a multitude of questions ranging from stellar evolution, colliding winds, chemical enrichment, nebular excitation to the formation of molecules and dust. Every 5.54 years, Eta Car changes from high excitation to several-months-long low excitation caused by modulation of the massive interacting winds due to a very eccentric binary orbit. The surrounding Homunculus (Figure 1) and Little Homunculus, thrown out in the 1840s Great Eruption and the 1890s Lesser Eruption, respond to the changing flux, providing clues to many physical phenomena of great interest to astrophysicists.

  3. Investigation of the electromagnetic structure of. eta. and. eta. prime mesons by two-photon interactions

    SciTech Connect

    Aihara, H.; Alston-Garnjost, M.; Avery, R.E.; Barbaro-Galtieri, A.; Barker, A.R.; Barnett, B.A.; Bauer, D.A.; Bay, A.; Bobbink, G.J.; Buchanan, C.D.; Buijs, A.; Caldwell, D.O.; Chao, H.; Chun, S.; Clark, A.R.; Cowan, G.D.; Crane, D.A.; Dahl, O.I.; Daoudi, M.; Derby, K.A.; Eastman, J.J.; Eberhard, P.H.; Edberg, T.K.; Eisner, A.M.; Erne, F.C.; Fairfield, K.H.; Hauptman, J.M.; Hofmann, W.; Hylen, J.; Kamae, T.; Kaye, H.S.; Kenney, R.W.; Khacheryan, S.; Kofler, R.R.; Langeveld, W.G.J.; Layter, J.G.; Lin, W.T.; Linde, F.L.; Loken, S.C.; Lu, A.; Lynch, G.R.; Madaras, R.J.; Magnuson, B.D.; Masek, G.E.; Mathis, L.G.; Matthews, J.A.J.; Maxfield, S.J.; Miller, E.S.; Moses, W.; Nygren, D.R.; Oddone, P.J.; Paar, H.P.; Park, S.K.; Pellett, D.E.; Pripstein, M.; Ronan, M.T.; Ross, R.R.; Rouse, F.R.; Schwitkis, K.A.; Sens, J.C.; Shapiro, G.; Shen, B.C.; Smith, J.R.; Steinman, J.S.; Stephens, R.W.; Stevenson, M.L.; Stork, D.H.; Strauss, M.G.; Sullivan, M.K.; Takahashi, T.; Toutounchi, S.; van Tyen, R.; TPC /Two-Gamma Collaboration

    1990-01-08

    The TPC/Two-Gamma facility at the SLAC {ital e}{sup +}{ital e}{sup {minus}} storage ring PEP was used to study the reactions {gamma}{gamma}{sup *}{r arrow}{eta} and {gamma}{gamma}{sup *}{r arrow}{eta}{prime}. The {eta}{gamma}{sup *}{gamma} and {eta}{prime}{gamma}{sup *}{gamma} transition form factors were measured as functions of {ital Q}{sup 2}, the negative of the invariant mass squared of the tagged photon, in the range 0.1{lt}{ital Q}{sup 2}{lt}7 GeV{sup 2}. These determinations of the electromagnetic structure of the {eta} and {eta}{prime} mesons are consistent with both vector-meson dominance and QCD. They also provide new measurements of the pseudoscalar mixing angle and decay constants.

  4. Accelerator research studies. Final report, June 1, 1990--November 30, 1991

    SciTech Connect

    Not Available

    1991-12-31

    The program consisted of the following three tasks: TASK A, ``Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams,`` TASK B, ``Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams,`` and TASK C, ``Study of a Gyroklystron High-Power Microwave Source for Linear Colliders.``

  5. Laser Wakefield Acceleration: Structural and Dynamic Studies. Final Technical Report ER40954

    SciTech Connect

    Downer, Michael C.

    2014-12-19

    Particle accelerators enable scientists to study the fundamental structure of the universe, but have become the largest and most expensive of scientific instruments. In this project, we advanced the science and technology of laser-plasma accelerators, which are thousands of times smaller and less expensive than their conventional counterparts. In a laser-plasma accelerator, a powerful laser pulse exerts light pressure on an ionized gas, or plasma, thereby driving an electron density wave, which resembles the wake behind a boat. Electrostatic fields within this plasma wake reach tens of billions of volts per meter, fields far stronger than ordinary non-plasma matter (such as the matter that a conventional accelerator is made of) can withstand. Under the right conditions, stray electrons from the surrounding plasma become trapped within these “wake-fields”, surf them, and acquire energy much faster than is possible in a conventional accelerator. Laser-plasma accelerators thus might herald a new generation of compact, low-cost accelerators for future particle physics, x-ray and medical research. In this project, we made two major advances in the science of laser-plasma accelerators. The first of these was to accelerate electrons beyond 1 gigaelectronvolt (1 GeV) for the first time. In experimental results reported in Nature Communications in 2013, about 1 billion electrons were captured from a tenuous plasma (about 1/100 of atmosphere density) and accelerated to 2 GeV within about one inch, while maintaining less than 5% energy spread, and spreading out less than ½ milliradian (i.e. ½ millimeter per meter of travel). Low energy spread and high beam collimation are important for applications of accelerators as coherent x-ray sources or particle colliders. This advance was made possible by exploiting unique properties of the Texas Petawatt Laser, a powerful laser at the University of Texas at Austin that produces pulses of 150 femtoseconds (1 femtosecond is 10

  6. Final report: Accelerated beta decay for disposal of fission fragment wastes

    SciTech Connect

    Reiss, Howard R.

    2000-03-06

    The fundamental theory of the interaction of intense, low-frequency electromagnetic fields with certain radioactive nuclei has been fully formulated. The nuclei are of the type that exists in high-level radioactive wastes that are end products of the production of energy from nuclear fission. The basic physical mechanisms that underlie the coupling of the applied field to the nucleus have been identified. Both the basic theory and numerical predictions that stem from it support the conclusion that high-level radioactive wastes can be disposed of by substantially accelerating the rate of radioactive decay. Some old experiments on the acceleration of this type of radioactivity, with results that were not understood at the time, have been re-examined. Their interpretation is now clear, and the experiments are found to be in agreement with the theory.

  7. Branching Fractions and CP-Violating Asymmetries in Radiative B Decays to eta K gamma

    SciTech Connect

    Aubert, B.

    2008-05-14

    The authors present measurements of the CP-violation parameters S and C for the radiative decay B{sup 0} {yields} {eta}K{sub S}{sup 0}{gamma}; for B {yields} {eta}K{gamma} they also measure the branching fractions and for B{sup +} {yields} {eta}K{sup +}{gamma} the time-integrated charge asymmetry {Alpha}{sub ch}. The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation. The results are S = -0.18{sub -0.46}{sup +0.49} {+-} 0.12, C = -0.32{sub -0.39}{sup +0.40} {+-} 0.07, {Beta}(B{sup 0} {yields} {eta}K{sup 0}{gamma}) = (7.1{sub -2.0}{sup +2.1} {+-} 0.4) x 10{sup -6}, {Beta}(B{sup +} {yields} {eta}K{sup +}{gamma}) = (7.7 {+-} 1.0 {+-} 0.4) x 10{sup -6}, and {Alpha}{sub ch} = (-9.0{sub -9.8}{sup +10.4} {+-} 1.4) x 10{sup -2}. The first error quoted is statistical and the second systematic.

  8. Evidence for the eta(b)(1S) meson in radiative Upsilon(2S) decay.

    PubMed

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Battaglia, M; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Randle-Conde, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Atmacan, H; Gary, J W; Liu, F; Long, O; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Heusch, C A; Kroseberg, J; Lockman, W S; Martinez, A J; Schalk, T; Schumm, B A; Seiden, A; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Nogowski, R; Schubert, K R; Schwierz, R; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Verderi, M; Clark, P J; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Contri, R; Lo Vetere, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Tosi, S; Chaisanguanthum, K S; Morii, M; Adametz, A; Marks, J; Schenk, S; Uwer, U; Bernlochner, F U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Firmino da Costa, J; Grosdidier, G; Le Diberder, F; Lepeltier, V; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Paramesvaran, S; Wren, A C; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Alwyn, K E; Bailey, D; Barlow, R J; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Henderson, S W; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Godang, R; Kroeger, R; Summers, D J; Zhao, H W; Simard, M; Taras, P; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Wang, W F; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Del Amo Sanchez, P; Ben-Haim, E; Briand, H; Chauveau, J; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Calderini, G; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Esteve, L; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Miyashita, T S; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; King, G J; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Puccio, E M T; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Prepost, R; Vuosalo, C O; Wu, S L

    2009-10-16

    We have performed a search for the eta_{b}(1S) meson in the radiative decay of the Upsilon(2S) resonance using a sample of 91.6x10(6) Upsilon(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at Egamma=609.3(-4.5)(+4.6)(stat)+/-1.9(syst) MeV, corresponding to an eta(b)(1S) mass of 9394.2(-4.9)(+4.8)(stat)+/-2.0(syst) MeV/c2. The branching fraction for the decay Upsilon(2S)-->gamma(eta)b(1S) is determined to be [3.9+/-1.1(stat)-0.9+1.1(syst)]x10(-4). We find the ratio of branching fractions B[Upsilon(2S)-->gamma(eta)b(1S)]/B[Upsilon(3S)-->gamma(eta)b(1S)]=0.82+/-0.24(stat)(-0.19)(+0.20)(syst). PMID:19905689

  9. Collective acceleration of electrons and ions in a high current relativistic electron beam. Final report

    SciTech Connect

    Nation, J.A.

    1992-12-31

    This report describes work carried out on DOE contract number DE-AC02-80ER10569 during the period December 15, 1979 to May 31, 1992. The original purpose of this research was to investigate the use of slow space charge waves on weakly relativistic electron beams for ion acceleration. The work had three major objectives: development of a suitable ion injector, growth and study of the properties of slow space charge waves on an electron beam, and a combination of the two components into a suitable proof-of-principle demonstration of the wave accelerator. Work focused on the first two of these objectives. Control of the space charge waves` phase velocity was not obtained to the degree required for a working accelerator, so the project was duly terminated in favor of a program which focused on generating ultra high power microwave signals suitable for use in the next linear collider. Work done to develop suitable efficient, inexpensive, phase-stable microwave sources, with peak powers of up to 1 GW in the X band in pulses shorter than 1 ns, is described. Included are lists of the journal and conference papers resulting from this work, as well as a list of graduate students who completed their Ph.D. studies on the projects described in this report.

  10. Accelerator research studies. Final report, June 1, 1994--May 31, 1995

    SciTech Connect

    1995-08-01

    The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy has completed the third year of its three-year funding cycle and an additional one-year, no-cost extension. The program consisted of the following three tasks: Task A -- Study of the transport and longitudinal compression of intense, high-brightness beams; Task B -- Study of high-brightness beam generation in pseudospark devices; Task C -- Study of a gyroklystron high-power microwave source for linear colliders. The research carried out for each task and progress made is reported.

  11. Accelerator research studies. Final report, June 1, 1991--May 31, 1994

    SciTech Connect

    1994-12-31

    The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy is currently in the third year of its three-year funding cycle. The program consists of the following three tasks: Task A -- Study of the transport and longitudinal compression of intense, high-brightness beams; Task B -- Study of high-brightness beam generation in pseudospark devices; Task C -- Study of a gyroklystron high-power microwave source for linear colliders. The research for each task is detailed in this report.

  12. Final report for CAFDA project entitled, Experimental and numerical investigation of accelerated fluid interface

    SciTech Connect

    Greenough, J.A.; Jacobs, J.W.; Marcus, D.L.

    1997-03-26

    The main thrust of this collaborative effort can be summarized as an attempt to use the strengths of physical experiments and numerical simulations in understanding the dynamics of accelerated interfaces. Laboratory experiments represent the true nature of the physical processes and the simulations represent a model of these processes. We have taken the first steps toward this goal through development and calibration of new experimental techniques as well as validation and direct, systematic, and quantitative comparison with computational results. This report summarizes accomplishments made towards these goals. More detailed information is provided in reprints appended to this document.

  13. Eta Squared and Partial Eta Squared as Measures of Effect Size in Educational Research

    ERIC Educational Resources Information Center

    Richardson, John T. E.

    2011-01-01

    Eta squared measures the proportion of the total variance in a dependent variable that is associated with the membership of different groups defined by an independent variable. Partial eta squared is a similar measure in which the effects of other independent variables and interactions are partialled out. The development of these measures is…

  14. Effect of {eta}-{eta}{sup '} mixing on D{yields}PV decays

    SciTech Connect

    Bhattacharya, Bhubanjyoti; Rosner, Jonathan L.

    2010-08-01

    Charmed meson decays to a light pseudoscalar (P) and light vector (V) meson are analyzed taking account of {eta}-{eta}{sup '} mixing. A frequently-used octet-singlet mixing angle of 19.5 degree sign is compared with a value of 11.7 degree sign favored by a recent analysis of D{yields}PP decays.

  15. Chiral corrections to the anomalous 2. gamma. decays of. pi. sup 0 ,. eta. and. eta. prime

    SciTech Connect

    Issler, D.

    1990-11-01

    To any order in chiral perturbation theory, the anomalous Wess-Zumino term is shown to generate only chirally invariant counterterms. Explicit examples of 0(p{sub 6}) terms generated by one-loop graphs are given, some of which are relevant to the two-photon decays of {pi}{sup o}, {eta} and {eta}{prime}.

  16. Final Commissioning of the Superconducting Heavy Ion Linear Accelerator at IUAC, Delhi

    NASA Astrophysics Data System (ADS)

    Datta, Tripti Sekhar; Choudhury, Anup; Chacko, Jacob; Kar, Soumen; Antony, Joby; Babu, Suresh; Kumar, Manoj; Mathuria, D. S.; Sahu, Santosh; Kanjilal, Dinakar

    The superconducting linac as a booster of the 15UD Pelletron accelerator was partly commissioned with one linac module housing eight quarter wave bulk niobium cavities along with the superbuncher and rebuncher cryomodules. Subsequently two more linac cryomodules were added to have in total 24 cavities for acceleration. In addition, a new Linde helium refrigerator of capacity 750 W @ 4.2 K was installed in parallel to the earlier CCI refrigerator. The new refrigerator was integrated with the earlier cryogenics network system through a specially designed liquid helium distribution line without any valve box. The cooling philosophy with this new system is modified to have a faster cool down rate in the critical zone (150 - 70 K) to avoid Q disease. The helium gas pressure fluctuation in the cavities is reduced significantly to have stable RF locking. The full linac is being operated and beams with higher energy are being delivered to the users. The present paper will highlight the performance of the new cryogenic system with respect to cool down rate, and helium pressure fluctuation.

  17. A 200 MHz 35 MW Multiple Beam Klystron for Accelerator Applications Final Report

    SciTech Connect

    R. Lawrence Ives; Michael Read; Patrick Ferguson; David Marsden

    2011-11-28

    Calabazas Creek Research, Inc. (CCR) performed initial development of a compact and reliable 35 MW, multiple beam klystron (MBK) at 200 MHz with a pulse length of 0.125 ms and a 30 Hz repetition rate. The device was targeted for acceleration and ionization cooling of a muon collider, but there are several other potential applications in this frequency range. The klystron uses multiple beams propagating in individual beam tunnels to reduce space charge and allow reduction in the accelerating voltage. This allows a significant reduction in length over a single beam source. More importantly this allows more efficient and less expensive power supplies. At 200 MHz, the interaction circuit for a single beam klystron would be more than six meters long to obtain 50% efficiency and 50 dB gain. This would require a beam voltage of approximately 400 kV and current of 251 A for a microperveance of 1.0. For an eight beam MBK with the same beam perveance, a three meter long interaction circuit achieves the same power and gain. Each beam operates at 142 kV and 70A. The Phase I demonstrated that this device could be fabricated with funding available in a Phase II program and could achieve the program specifications.

  18. Final Report 200 MW L-Band Annular Beam Klystron for Accelerators

    SciTech Connect

    Read, Michael; Ferguson, Patrick; Ives, Lawrence; Song, Liqun; Carlsten, Bruce; Fazio, Michael

    2009-02-11

    This program developed a 200 MW, 1.3 GHz, Annular Beam Klystron (ABK) for accelerator systems. An ABK provides lower impedance than a conventional klystron, making it possible to produce higher RF powers with lower voltages. With a higher power per unit, fewer klystrons would be required for a large accelerator. Lower voltage also simplifies and reduces the cost of the power supply system. Both features will significantly lower the cost of an RF system. This device operates at 475 kV. The klystron uses a magnetron injection gun producing 1100 A in one microsecond pulses. Power is extracted into fundamental rectangular waveguide through two output windows. The predicted gain is approximately 45 dB with estimated efficiency of 45%. The klystron was assembled, but no facility was available for testing. Consequently, no high power performance measurements are available. Because the assembled klystron is approximately 15 feet long, it was disassembled for storage. It can be reassembled should a use materialize.

  19. School Nurse Achievement Program II: Curriculum Adaptation for Expanded and Accelerated Dissemination. Final Report.

    ERIC Educational Resources Information Center

    Smith, Ann N.; Burgess, Heidi

    The final report of a 3-year project to improve the delivery of inservice training for school nurses through the development of computer assisted instructional programs and videotapes concerning handicapped children is presented. The School Nurse Achievement Program (SNAP) is an on-going national inservice training course. The evaluation project…

  20. Observation of B to eta' K* and Evidence for B+ to eta' rho+

    SciTech Connect

    Aubert, B

    2006-09-26

    The authors presented an observation of B {yields} {eta}{prime}K*. The data sample corresponds to 232 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. They measure the branching fractions (in units of 10{sup -6}) {Beta}(B{sup 0} {yields} {eta}{prime}K*{sup 0}) = 3.8 {+-} 1.1 {+-} 0.5 and {Beta}(B{sup +} {yields} {eta}{prime}K*{sup +}) = 4.9{sub -1.7}{sup +1.9} {+-} 0.8, where the first error is statistical and the second systematic. A simultaneous fit results in the observation of B {yields} {eta}{prime}K* with {Beta}(B {yields} {eta}{prime}K*) = 4.1{sub -0.9}{sup +1.0} {+-} 0.5. They also search for B {yields} {eta}{prime}{rho} and {eta}{prime} f{sub 0}(980)(f{sub 0} {yields} {pi}{sup +}{pi}{sup -}) with results and 90% confidence level upper limits {Beta}(B{sup +} {yields} {eta}{prime}{rho}{sup +}) = 8.7{sub -2.8-1.3}{sup +3.1+2.3} (< 14), {Beta}(B{sup 0} {yields} {eta}{prime}{rho}{sup 0}) < 3.7, and {Beta}(B{sup 0} {yields} {eta}{prime} f{sub 0}(980)(f{sub 0} {yields} {pi}{sup +}{pi}{sup -})) < 1.5. Charge asymmetries in the channels with significant yields are consistent with zero.

  1. Accelerating Energy Efficiency in Indian Data Centers. Final Report for Phase I Activities

    SciTech Connect

    Ganguly, Suprotim; Raje, Sanyukta; Kumar, Satish; Sartor, Dale; Greenberg, Steve

    2016-01-01

    This report documents Phase 1 of the “Accelerating Energy Efficiency in Indian Data Centers” initiative to support the development of an energy efficiency policy framework for Indian data centers. The initiative is being led by the Confederation of Indian Industry (CII), in collaboration with Lawrence Berkeley National Laboratory (LBNL)-U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy, and under the guidance of Bureau of Energy Efficiency (BEE). It is also part of the larger Power and Energy Efficiency Working Group of the US-India Bilateral Energy Dialogue. The initiative consists of two phases: Phase 1 (November 2014 – September 2015) and Phase 2 (October 2015 – September 2016).

  2. Final safety analysis report for the Ground Test Accelerator (GTA), Phase 2

    SciTech Connect

    1994-10-01

    This document is the first volume of a 3 volume safety analysis report on the Ground Test Accelerator (GTA). The GTA program at the Los Alamos National Laboratory (LANL) is the major element of the national Neutral Particle Beam (NPB) program, which is supported by the Strategic Defense Initiative Office (SDIO). A principal goal of the national NPB program is to assess the feasibility of using hydrogen and deuterium neutral particle beams outside the Earth`s atmosphere. The main effort of the NPB program at Los Alamos concentrates on developing the GTA. The GTA is classified as a low-hazard facility, except for the cryogenic-cooling system, which is classified as a moderate-hazard facility. This volume consists of an introduction, summary/conclusion, site description and assessment, description of facility, and description of operation.

  3. Final safety analysis report for the Ground Test Accelerator (GTA), Phase 2

    SciTech Connect

    1994-10-01

    This document is the third volume of a 3 volume safety analysis report on the Ground Test Accelerator (GTA). The GTA program at the Los Alamos National Laboratory (LANL) is the major element of the national Neutral Particle Beam (NPB) program, which is supported by the Strategic Defense Initiative Office (SDIO). A principal goal of the national NPB program is to assess the feasibility of using hydrogen and deuterium neutral particle beams outside the Earth`s atmosphere. The main effort of the NPB program at Los Alamos concentrates on developing the GTA. The GTA is classified as a low-hazard facility, except for the cryogenic-cooling system, which is classified as a moderate-hazard facility. This volume consists of appendices C through U of the report

  4. Dedekind's eta-function and the cohomology of infinite dimensional Lie algebras.

    PubMed

    Garland, H

    1975-07-01

    We compute the cohomology of certain infinite dimensional Lie algebras which are subalgebras of Lie algebras introduced by Moody and Kac. We note a relation between our results and the cohomology of loop spaces of compact groups. Finally, we derive, by Euler-Poincaré, identities of Macdonald for powers of the Dedekind eta-function. PMID:16592258

  5. Eta Carinae: Orientation of The Orbital Plane

    NASA Technical Reports Server (NTRS)

    Gull, T. R.; Nielsen, K. E.; Ivarsson, S.; Corcoran, M. F.; Verner, E.; Hillier, J. D.

    2006-01-01

    Evidence continues to build that Eta Carinae is a massive binary system with a hidden hot companion in a highly elliptical orbit. We present imaging and spectroscopic evidence that provide clues to the orientation of the orbital plane. The circumstellar ejecta, known as the Homunculus and Little Homunculus, are hourglass-shaped structures, one encapsulated within the other, tilted at about 45 degrees from the sky plane. A disk region lies between the bipolar lobes. Based upon their velocities and proper motions, Weigelt blobs B, C and D, very bright emission clumps 0.1 to 0.3" Northwest from Eta Carinae, lie in the disk. UV flux from the hot companion, Eta Car B, photoexcites the Weigelt blobs. Other clumps form a complete chain around the star, but are not significantly photoexcited. The strontium filament, a 'neutral' emission structure, lies in the same general direction as the Weigelt blobs and exhibits peculiar properties indicative that much mid-UV, but no hydrogen-ionizing radiation impinges on this structure. It is shielded by singly-ionized iron. P Cygni absorptions in Fe I I lines, seen directly in line of sight from Eta Carinae, are absent in the stellar light scattered by the Weigelt blobs. Rather than a strong absorption extending to -600 km/s, a low velocity absorption feature extends from -40 to -150 km/s. No absorbing Fe II exists between Eta Carinae and Weigelt D, but the outer reaches of the wind are intercepted in line of sight from Weigelt D to the observer. This indicates that the UV radiation is constrained by the dominating wind of Eta Car A to a small cavity carved out by the weaker wind of Eta Car B. Since the high excitation nebular lines are seen in the Weigelt blobs at most phases, the cavity, and hence the major axis of the highly elliptical orbit, must lie in the general direction of the Weigelt blobs. The evidence is compelling that the orbital major axis of Eta Carinae is projected at -45 degrees position angle on the sky. Moreover

  6. Eta Carinae, the most brutal binary bipolar

    NASA Astrophysics Data System (ADS)

    Icke, V.

    Eta Carinae, one of the most extreme and fascinating objects in our Galaxy, is a supermassive interacting binary at the centre of a bipolar nebula, expanding at about 500 km s^{-1}. Finding the mechanisms behind Eta's appearance, behaviour and evolution is the main goal of this investigation. I have constructed a large series of numerical models of dual-wind binary stars, of which I present here one that probably comes close to the Eta Carinae parameters. I presume that the gaseous `skirt' surrounding Eta is an equatorial `excretion disk' formed by the interacting binary, that the bipolar `Homunculus' nebula above and below this plane is due to the collision between the material ejected in the 1840 `Giant Eruption' and the disk, and the `Little Homunculus' similarly in the smaller 1890 eruption. I have extensively explored the general types of flow pattern expected here. My Theory Group is working towards 3D radiation-hydrodynamics simulations for quantitative comparison with Eta, which many believe to be a key to understanding a variety of hitherto unexplained phenomena in and around massive stars, be they binary or single.

  7. Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling (Final Report)

    SciTech Connect

    William J. Schroeder

    2011-11-13

    This report contains the comprehensive summary of the work performed on the SBIR Phase II, Collaborative Visualization for Large-Scale Accelerator Electromagnetic Modeling at Kitware Inc. in collaboration with Stanford Linear Accelerator Center (SLAC). The goal of the work was to develop collaborative visualization tools for large-scale data as illustrated in the figure below. The solutions we proposed address the typical problems faced by geographicallyand organizationally-separated research and engineering teams, who produce large data (either through simulation or experimental measurement) and wish to work together to analyze and understand their data. Because the data is large, we expect that it cannot be easily transported to each team member's work site, and that the visualization server must reside near the data. Further, we also expect that each work site has heterogeneous resources: some with large computing clients, tiled (or large) displays and high bandwidth; others sites as simple as a team member on a laptop computer. Our solution is based on the open-source, widely used ParaView large-data visualization application. We extended this tool to support multiple collaborative clients who may locally visualize data, and then periodically rejoin and synchronize with the group to discuss their findings. Options for managing session control, adding annotation, and defining the visualization pipeline, among others, were incorporated. We also developed and deployed a Web visualization framework based on ParaView that enables the Web browser to act as a participating client in a collaborative session. The ParaView Web Visualization framework leverages various Web technologies including WebGL, JavaScript, Java and Flash to enable interactive 3D visualization over the web using ParaView as the visualization server. We steered the development of this technology by teaming with the SLAC National Accelerator Laboratory. SLAC has a computationally-intensive problem

  8. Eta photoproduction in a combined analysis of pion- and photon-induced reactions

    SciTech Connect

    Ronchen, D.; Doring, M.; Haberzettl, H.; Haidenbauer, J.; MeiBner, U. -G.; Nakayama, K.

    2015-06-25

    The $\\eta N$ final state is isospin-selective and thus provides access to the spectrum of excited nucleons without being affected by excited $\\Delta$ states. To this end, the world database on eta photoproduction off the proton up to a center-of-mass energy of $E\\sim 2.3$ GeV is analyzed, including data on differential cross sections, and single and double polarization observables. The resonance spectrum and its properties are determined in a combined analysis of eta and pion photoproduction off the proton together with the reactions $\\pi N\\to \\pi N$, $\\eta N$, $K\\Lambda$ and $K\\Sigma$. For the analysis, the so-called J\\"ulich coupled-channel framework is used, incorporating unitarity, analyticity, and effective three-body channels. Parameters tied to photoproduction and hadronic interactions are varied simultaneously. Furthermore, the influence of recent MAMI $T$ and $F$ asymmetry data on the eta photoproduction amplitude is discussed in detail.

  9. Eta photoproduction in a combined analysis of pion- and photon-induced reactions

    DOE PAGESBeta

    Ronchen, D.; Doring, M.; Haberzettl, H.; Haidenbauer, J.; MeiBner, U. -G.; Nakayama, K.

    2015-06-25

    Themore » $$\\eta N$$ final state is isospin-selective and thus provides access to the spectrum of excited nucleons without being affected by excited $$\\Delta$$ states. To this end, the world database on eta photoproduction off the proton up to a center-of-mass energy of $$E\\sim 2.3$$ GeV is analyzed, including data on differential cross sections, and single and double polarization observables. resonance spectrum and its properties are determined in a combined analysis of eta and pion photoproduction off the proton together with the reactions $$\\pi N\\to \\pi N$$, $$\\eta N$$, $$K\\Lambda$$ and $$K\\Sigma$$. For the analysis, the so-called J\\"ulich coupled-channel framework is used, incorporating unitarity, analyticity, and effective three-body channels. Parameters tied to photoproduction and hadronic interactions are varied simultaneously. Furthermore, the influence of recent MAMI $T$ and $F$ asymmetry data on the eta photoproduction amplitude is discussed in detail.« less

  10. Final Report: MATERIALS, STRANDS, AND CABLES FOR SUPERCONDUCTING ACCELERATOR MAGNETS [Grant Number DE-SC0010312

    SciTech Connect

    Sumption, Mike; Collings, E.

    2014-10-29

    Our program consisted of the two components: Strand Research and Cable Research, with a focus on Nb3Sn, Bi2212, and YBCO for accelerator magnet applications. We demonstrated a method to refine the grains in Nb3Sn by a factor of two, reaching 45 nm grain sizes, and layer Jcs of 6 kA/mm2 at 12 T. W also measured conductor magnetization for field quality. This has been done both with Nb3Sn conductor, as well as Bi:2212 strand. Work in support of quench studies of YBCO coils was also performed. Cable loss studies in Nb3Sn focused on connecting and comparing persistent magnetization and coupling magnetization for considering their relative impact on HEP machines. In the area of HTS cables, we have investigated both the quench in multistrand YBCO CORC cables, as well as the magnetization of these cables for use in high field magnets. In addition, we examined the magnetic and thermal properties of large (50 T) solenoids.

  11. Mobile-accelerator neutron-radiography system. Final report, February 1978-December 1983

    SciTech Connect

    Dance, W.E.; Carollo, S.F.; Bumgardner, H.M.

    1984-10-01

    The use of neutron radiography for the inspection and maintenance of large structures such as aircraft has been delayed by the absence of a mobile system particularly suited to the requirements of field use. This report describes the production, extensive field testing, evaluation and disposition of the first mobile neutron radiography system to satisfy the majority of requirements for field use. The system is based upon the concept of a mobile on-off neutron radiography system based on a sealed-tube ion accelerator as neutron source demonstrated earlier by the Vought Corporation. Primary features of the system are its self-propelled mobility, versatile positioning capability scaled to Army helicopter dimensions, an on-off beam capability, exposure capability measured in minutes, and suitability for AMMRC laboratory and field use. Included in the report are a description of all components of the system, an evaluation of the operation of the system, an evaluation of its radiographic capabilities, a description of installation elements for the AMMRC site, and recommendations for next-generation systems.

  12. Laser Wakefield Acceleration Driven by a CO2 Laser (STELLA-LW) - Final Report

    SciTech Connect

    Kimura, Wayne D

    2008-06-27

    The original goals of the Staged Electron Laser Acceleration – Laser Wakefield (STELLA-LW) program were to investigate two new methods for laser wakefield acceleration (LWFA). In pseudo-resonant LWFA (PR-LWFA), a laser pulse experiences nonlinear pulse steepening while traveling through the plasma. This steepening allows the laser pulse to generate wakefields even though the laser pulse length is too long for resonant LWFA to occur. For the conditions of this program, PR-LWFA requires a minimum laser peak power of 3 TW and a low plasma density (10^16 cm^-3). Seeded self-modulated LWFA (seeded SM-LWFA) combines LWFA with plasma wakefield acceleration (PWFA). An ultrashort (~100 fs) electron beam bunch acts as a seed in a plasma to form a wakefield via PWFA. This wakefield is subsequently amplified by the laser pulse through a self-modulated LWFA process. At least 1 TW laser power and, for a ~100-fs bunch, a plasma density ~10^17 cm^-3 are required. STELLA-LW was located on Beamline #1 at the Brookhaven National Laboratory (BNL) Accelerator Test Facility (ATF). The ATF TW CO2 laser served as the driving laser beam for both methods. For PR-LWFA, a single bunch was to probe the wakefield produced by the laser beam. For seeded SM-LWFA, the ATF linac would produce two bunches, where the first would be the seed and the second would be the witness. A chicane would compress the first bunch to enable it to generate wakefields via PWFA. The plasma source was a short-length, gas-filled capillary discharge with the laser beam tightly focused in the center of the capillary, i.e., no laser guiding was used, in order to obtain the needed laser intensity. During the course of the program, several major changes had to be made. First, the ATF could not complete the upgrade of the CO2 laser to the 3 TW peak power needed for the PR-LWFA experiment. Therefore, the PR-LWFA experiment had to be abandoned leaving only the seeded SM-LWFA experiment. Second, the ATF discovered that the

  13. Final safety analysis report for the Ground Test Accelerator (GTA), Phase 2

    SciTech Connect

    1994-10-01

    This document is the second volume of a 3 volume safety analysis report on the Ground Test Accelerator (GTA). The GTA program at the Los Alamos National Laboratory (LANL) is the major element of the national Neutral Particle Beam (NPB) program, which is supported by the Strategic Defense Initiative Office (SDIO). A principal goal of the national NPB program is to assess the feasibility of using hydrogen and deuterium neutral particle beams outside the Earth`s atmosphere. The main effort of the NPB program at Los Alamos concentrates on developing the GTA. The GTA is classified as a low-hazard facility, except for the cryogenic-cooling system, which is classified as a moderate-hazard facility. This volume consists of failure modes and effects analysis; accident analysis; operational safety requirements; quality assurance program; ES&H management program; environmental, safety, and health systems critical to safety; summary of waste-management program; environmental monitoring program; facility expansion, decontamination, and decommissioning; summary of emergency response plan; summary plan for employee training; summary plan for operating procedures; glossary; and appendices A and B.

  14. The electroproduction of etas and kaons

    SciTech Connect

    O.K. Baker

    2001-12-01

    Experimental results for the electromagnetic production of eta and K mesons are compared with QCD-inspired models. The eta mesons from the decay of S_11 resonance were used to study the momentum transfer dependence of the relevant helicity amplitude and cross section in the reaction ^1H(e,e'p)eta. The ^1H(e,e'K+)Lambda reaction was studied as a function of squared four-momentum transfer, Q^2, and of the virtual photon polarization parameter, epsilon. Both of these experiments were performed at Jefferson Lab during the early years of operation. The new precision data serve to constrain model calculations and provide new insights into the physical processes.

  15. Horizon crossing and inflation with large {eta}

    SciTech Connect

    Kinney, William H.

    2005-07-15

    I examine the standard formalism of calculating curvature perturbations in inflation at horizon crossing, and derive a general relation which must be satisfied for the horizon-crossing formalism to be valid. This relation is satisfied for the usual cases of power-law and slow-roll inflation. I then consider a model for which the relation is strongly violated, and the curvature perturbation evolves rapidly on superhorizon scales. This model has Hubble slow-roll parameter {eta}=3, but predicts a scale-invariant spectrum of density perturbations. I consider the case of hybrid inflation with large {eta}, and show that such solutions do not solve the '{eta} problem' in supergravity. These solutions correspond to field evolution which has not yet relaxed to the inflationary attractor solution, and may make possible new, more natural models on the string landscape.

  16. Design and Evaluation of a Clock Multiplexing Circuit for the SSRL Booster Accelerator Timing System - Final Paper

    SciTech Connect

    Araya, Million

    2015-08-21

    SPEAR3 is a 234 m circular storage ring at SLAC’s synchrotron radiation facility (SSRL) in which a 3 GeV electron beam is stored for user access. Typically the electron beam decays with a time constant of approximately 10hr due to electron lose. In order to replenish the lost electrons, a booster synchrotron is used to accelerate fresh electrons up to 3GeV for injection into SPEAR3. In order to maintain a constant electron beam current of 500mA, the injection process occurs at 5 minute intervals. At these times the booster synchrotron accelerates electrons for injection at a 10Hz rate. A 10Hz 'injection ready' clock pulse train is generated when the booster synchrotron is operating. Between injection intervals-where the booster is not running and hence the 10 Hz ‘injection ready’ signal is not present-a 10Hz clock is derived from the power line supplied by Pacific Gas and Electric (PG&E) to keep track of the injection timing. For this project I constructed a multiplexing circuit to 'switch' between the booster synchrotron 'injection ready' clock signal and PG&E based clock signal. The circuit uses digital IC components and is capable of making glitch-free transitions between the two clocks. This report details construction of a prototype multiplexing circuit including test results and suggests improvement opportunities for the final design.

  17. Experimental puzzles in heavy flavor decays anomalously high {eta}' appearance in charmless strange B decays - flavor SU(3) breaking in charm decays.

    SciTech Connect

    Lipkin, H. J.; High Energy Physics; Weizmann Inst. of Sciences; Tel Aviv Univ.

    2000-11-30

    Simple experimental tests are proposed which can clarify the origin for the anomalously high {eta}' appearance in charmless strange final states in B decays and can investigate the nature of SU(3) symmetry-breaking in weak heavy flavor decays.

  18. Study of high momentum eta' production in B --> eta'Xs.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Watson, N K; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmuecker, H; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Mackay, C; Wilson, F F; Abe, K; Cuhadar-Donszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Teodorescu, L; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Gary, J W; Layter, J; Shen, B C; Wang, K; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Beringer, J; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Erwin, R J; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, J; Schubert, K R; Schwierz, R; Spaan, B; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Khan, A; Lavin, D; Muheim, F; Playfer, S; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Grenier, G J; Lee, S-J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Brigljević, V; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, E; Gamet, R; Kay, M; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Cote-Ahern, D; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; John, M J J; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Del Gamba, V; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lu, C; Miftakov, V; Olsen, J; Smith, A J S; Varnes, E W; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yeche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Convery, M R; Cristinziani, M; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Elsen, E E; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Johnson, J R; Kutter, P E; Li, H; Liu, R; Di Lodovico, F; Mihalyi, A; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Neal, H

    2004-08-01

    We measure the branching fraction for the charmless semi-inclusive process B --> eta'Xs, where the eta' meson has a momentum in the range 2.0 to 2.7 GeV/c in the upsilon4S center-of-mass frame and Xs represents a system comprising a kaon and zero to four pions. We find B(B --> eta'Xs) = [3.9 +/- 0.8(stat) +/- 0.5(syst) +/- 0.8(model)] x 10(-4). We also obtain the Xs mass spectrum and find that it fits models predicting high masses. PMID:15323619

  19. An upgraded version of the Eta model

    NASA Astrophysics Data System (ADS)

    Mesinger, Fedor; Chou, Sin Chan; Gomes, Jorge L.; Jovic, Dusan; Bastos, Paulo; Bustamante, Josiane F.; Lazic, Lazar; Lyra, André A.; Morelli, Sandra; Ristic, Ivan; Veljovic, Katarina

    2012-05-01

    Upgrades implemented over a number of years in an open source version of the Eta model, posted at the CPTEC web site http://etamodel.cptec.inpe.br/ , are summarized and examples of benefits are shown. The version originates from the NCEP's Workstation Eta code posted on the NCEP web site http://www.emc.ncep.noaa.gov/mmb/wrkstn_eta eta" TargetType="URL"/> , which differs from the NCEP's latest operational Eta by having the WRF-NMM nonhydrostatic option included. Most of the upgrades made resulted from attention paid to less than satisfactory performance noted in several Eta results, and identification of the reasons for the problem. Others came from simple expectation that including a feature that is physically justified but is missing in the code should help. The most notable of the upgrades are the introduction of the so-called sloping steps, or discretized shaved cells topography; piecewise-linear finite-volume vertical advection of dynamic variables; vapor and hydrometeor loading in the hydrostatic equation, and changes aimed at refining the convection schemes available in the Eta. Several other modifications have to do with the calculation of exchange coefficients, conservation in the vertical diffusion, and diagnostic calculation of 10-m winds. Several examples showing improved performance resulting from the dynamics changes are given. One includes a case of unrealistically low temperatures in several mountain basins generated by a centered vertical advection difference scheme's unphysical advection from below ground, removed by its replacement with a finite-volume scheme. Another is that of increased katabatic winds in the Terra Nova Bay Antarctica region. Successful forecast of the severe downslope zonda wind case in the lee of

  20. THE LONG-LIVED DISKS IN THE {eta} CHAMAELEONTIS CLUSTER

    SciTech Connect

    Sicilia-Aguilar, Aurora; Bouwman, Jeroen; Juhasz, Attila; Henning, Thomas; Roccatagliata, Veronica; Lawson, Warrick A.; Acke, Bram; Decin, Leen; Feigelson, Eric D.; Tielens, A. G. G. M.; Meeus, Gwendolyn

    2009-08-20

    We present Infrared Spectrograph spectra and revised Multiband Imaging Photometer photometry for the 18 members of the {eta} Chamaeleontis cluster. Aged 8 Myr, the {eta} Cha cluster is one of the few nearby regions within the 5-10 Myr age range, during which the disk fraction decreases dramatically and giant planet formation must come to an end. For the 15 low-mass members, we measure a disk fraction {approx}50%, high for their 8 Myr age, and four of the eight disks lack near-IR excesses, consistent with the empirical definition of 'transition' disks. Most of the disks are comparable to geometrically flat disks. The comparison with regions of different ages suggests that at least some of the 'transition' disks may represent the normal type of disk around low-mass stars. Therefore, their flattened structure and inner holes may be related to other factors (initial masses of the disk and the star, environment, binarity), rather than to pure time evolution. We analyze the silicate dust in the disk atmosphere, finding moderate crystalline fractions ({approx}10%-30%) and typical grain sizes {approx}1-3 {mu}m, without any characteristic trend in the composition. These results are common to other regions of different ages, suggesting that the initial grain processing occurs very early in the disk lifetime (<1 Myr). Large grain sizes in the disk atmosphere cannot be used as a proxy for age, but are likely related to higher disk turbulence. The dust mineralogy varies between the 8-12 {mu}m and the 20-30 {mu}m features, suggesting high temperature dust processing and little radial mixing. Finally, the analysis of IR and optical data on the B9 star {eta} Cha reveals that it is probably surrounded by a young debris disk with a large inner hole, instead of being a classical Be star.

  1. 31 CFR 208.5 - Availability of the ETA SM.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 2 2014-07-01 2014-07-01 false Availability of the ETA SM. 208.5... DISBURSEMENTS § 208.5 Availability of the ETA SM. An individual who receives a Federal benefit, wage, salary, or retirement payment shall be eligible to open an ETA SM at any Federally-insured financial institution...

  2. 31 CFR 208.5 - Availability of the ETA SM.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false Availability of the ETA SM. 208.5... DISBURSEMENTS § 208.5 Availability of the ETA SM. An individual who receives a Federal benefit, wage, salary, or retirement payment shall be eligible to open an ETA SM at any Federally-insured financial institution...

  3. 31 CFR 208.5 - Availability of the ETA SM.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Availability of the ETA SM. 208.5... DISBURSEMENTS § 208.5 Availability of the ETA SM. An individual who receives a Federal benefit, wage, salary, or retirement payment shall be eligible to open an ETA SM at any Federally-insured financial institution...

  4. 31 CFR 208.5 - Availability of the ETA SM.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Availability of the ETA SM. 208.5... DISBURSEMENTS § 208.5 Availability of the ETA SM. An individual who receives a Federal benefit, wage, salary, or retirement payment shall be eligible to open an ETA SM at any Federally-insured financial institution...

  5. 31 CFR 208.5 - Availability of the ETA SM.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false Availability of the ETA SM. 208.5... DISBURSEMENTS § 208.5 Availability of the ETA SM. An individual who receives a Federal benefit, wage, salary, or retirement payment shall be eligible to open an ETA SM at any Federally-insured financial institution...

  6. Plasma accelerators

    SciTech Connect

    Ruth, R.D.; Chen, P.

    1986-03-01

    In this paper we discuss plasma accelerators which might provide high gradient accelerating fields suitable for TeV linear colliders. In particular we discuss two types of plasma accelerators which have been proposed, the Plasma Beat Wave Accelerator and the Plasma Wake Field Accelerator. We show that the electric fields in the plasma for both schemes are very similar, and thus the dynamics of the driven beams are very similar. The differences appear in the parameters associated with the driving beams. In particular to obtain a given accelerating gradient, the Plasma Wake Field Accelerator has a higher efficiency and a lower total energy for the driving beam. Finally, we show for the Plasma Wake Field Accelerator that one can accelerate high quality low emittance beams and, in principle, obtain efficiencies and energy spreads comparable to those obtained with conventional techniques.

  7. Microwave and accelerator research. Final report on Grant DE-FG02-92ER40731

    SciTech Connect

    Nation, John A.

    2002-09-01

    This report summarizes the main technical objectives and accomplishments during the life of the grant, and concludes with data on publications describing the research. The main activity was the development of very high power microwave sources, initially in X-band, and recent initial work on a Ka band TWT amplifier. There was additional activity on ferroelectric emitters. Highlights include the following: (1) The development of a relatively broad band microwave source yielding approx. 75 MW power at a power efficiency of 54% and an energy conversion efficiency of 43%. (2) The development of a ferroelectric cathode electron gun which yielded a beam current of up to 350 A at 500 kV. The device was shown to operate satisfactorily at a low repetition rate, limited by the available power supplies. The final beam power obtained exceeds that achieved elsewhere by several orders of magnitude. The gun development achieved was shown to give an electron beam suitable for high power X-band microwave sources with the demonstration of a 5-MW tunable X-band TWT single-stage amplifier. (3) Work was initiated on a Ka-Band TWT amplifier. Gains of over 30 dB were achieved at peak output powers of about 4 MW. Appendices include two submitted papers: Symmetric and asymmetric mode interaction in high-power traveling wave amplifiers: experiments and theory and High power microwave generation using a ferroelectric cathode electron gun.

  8. THE ENVIRONMENTAL TECHNOLOGIES ACCEPTANCE (ETA) PROGRAM

    SciTech Connect

    Christina B. Behr-Andres

    2001-10-01

    The objective of the Environmental Technologies Acceptance (ETA) Program at the Energy & Environmental Research Center (EERC) is to advance the development, commercial acceptance, and timely deployment of selected private sector technologies for the cleanup of sites in the nuclear defense complex as well as the greater market. As a result of contract changes approved by National Energy Technology Laboratory (NETL) representatives to incorporate activities previously conducted under another NETL agreement, there are now an additional task and an expansion of activities within the stated scope of work of the ETA program. As shown in Table 1, this cooperative agreement, funded by NETL (No. DE-FC26-00NT40840), consists of four tasks: Technology Selection, Technology Development, Technology Verification, and System Engineering. As currently conceived, ETA will address the needs of as many technologies as appropriate under its current 3-year term. There are currently four technical subtasks: Long-Term Stewardship Initiative at the Mound Plant Site; Photocatalysis of Mercury-Contaminated Water; Subcritical Water Treatment of PCB and Metal-Contaminated Paint Waste; and Vegetative Covers for Low-Level Waste Repositories. This report covers activities during the second six months of the three-year ETA program.

  9. Superluminous supernovae: no threat from eta Carinae.

    PubMed

    Thomas, Brian C; Melott, Adrian L; Fields, Brian D; Anthony-Twarog, Barbara J

    2008-02-01

    Recently, Supernova 2006gy was noted as the most luminous ever recorded, with a total radiated energy of approximately 10(44) Joules. It was proposed that the progenitor may have been a massive evolved star similar to eta Carinae, which resides in our own Galaxy at a distance of about 2.3 kpc. eta Carinae appears ready to detonate. Although it is too distant to pose a serious threat as a normal supernova, and given that its rotation axis is unlikely to produce a gamma-ray burst oriented toward Earth, eta Carinae is about 30,000 times nearer than 2006gy, and we re-evaluate it as a potential superluminous supernova. We have found that, given the large ratio of emission in the optical to the X-ray, atmospheric effects are negligible. Ionization of the atmosphere and concomitant ozone depletion are unlikely to be important. Any cosmic ray effects should be spread out over approximately 10(4) y and similarly unlikely to produce any serious perturbation to the biosphere. We also discuss a new possible effect of supernovae-e-ndocrine disruption induced by blue light near the peak of the optical spectrum. This is a possibility for nearby supernovae at distances too large to be considered "dangerous" for other reasons. However, due to reddening and extinction by the interstellar medium, eta Carinae is unlikely to trigger such effects to any significant degree. PMID:18199005

  10. A SEA CHANGE IN ETA CARINAE

    SciTech Connect

    Mehner, Andrea; Davidson, Kris; Humphreys, Roberta M.; Martin, John C.; Ishibashi, Kazunori; Ferland, Gary J.; Walborn, Nolan R.

    2010-07-01

    Major stellar-wind emission features in the spectrum of {eta} Car have recently decreased by factors of order 2 relative to the continuum. This is unprecedented in the modern observational record. The simplest, but unproven, explanation is a rapid decrease in the wind density.

  11. Interaction of eta mesons with nuclei

    NASA Astrophysics Data System (ADS)

    Kelkar, N. G.; Khemchandani, K. P.; Upadhyay, N. J.; Jain, B. K.

    2013-06-01

    Back in the mid-1980s, a new branch of investigation related to the interaction of eta mesons with nuclei came into existence. It started with the theoretical prediction of possible exotic states of eta mesons and nuclei bound by the strong interaction and later developed into an extensive experimental program to search for such unstable states as well as understand the underlying interaction via eta-meson producing reactions. The vast literature of experimental as well as theoretical works that studied various aspects of eta-producing reactions such as the π+n → ηp, pd → 3Heη, p 6Li → 7Be η and γ 3He → η X, to name a few, had but one objective in mind: to understand the eta-nucleon (ηN) and hence the η-nucleus interaction which could explain the production data and confirm the existence of some η-mesic nuclei. In spite of these efforts, there remain uncertainties in the knowledge of the ηN and hence the η-nucleus interaction. Therefore, this review is an attempt to bind together the findings in these works and draw some global and specific conclusions which can be useful for future explorations. The ηN scattering length (which represents the strength of the η-nucleon interaction) using different theoretical models and analyzing the data on η production in pion, photon and proton induced reactions was found to be spread out in a wide range, namely, 0.18 ⩽ ℜe aηN ⩽ 1.03 fm and 0.16 ⩽ ℑm aηN ⩽ 0.49 fm. Theoretical searches of heavy η-mesic nuclei based on η-nucleus optical potentials and lighter ones based on Faddeev type few-body approaches predict the existence of several quasibound and resonant states. Although some hints of η-mesic states such as ^3_{\\eta} He and ^{25}_{\\eta} Mg do exist from previous experiments, the promise of clearer signals for the existence of η-mesic nuclei lies in the experiments to be performed at the J-PARC, MAMI and COSY facilities in the near future. This review is aimed at giving an overall

  12. Some Comments on the Decays of eta (550)

    DOE R&D Accomplishments Database

    Veltman, M.; Yellin, J.

    1966-07-01

    Various decay modes of the {eta}(500) are discussed. The relations, through SU{sub 3} and the Gell-Mann, Sharp, Wagner model, between the {eta}-decay modes and the modes {eta} {yields} {pi}{pi}{gamma), {pi}{sup 0} {yields} {gamma}{gamma} are investigated taking into account {eta}-{eta}{sup *} mixing. The present experimental values for the neutral branching ratios plus the shape of the {eta} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} Dalitz plot are shown to require a 25% {vert_bar}{Delta}{rvec I}{vert_bar} = 3 contribution to the {eta} {yields} 3{pi} amplitude. The connection between a possible charge asymmetry in {eta} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} and the branching ratio {Gamma}{sub {eta} {yields} {pi}{sup 0}e{sup +}e{sup {minus}}}/{Gamma}{sub {eta}}{sup all} is investigated in the framework of a model proposed earlier by several authors. It is shown that there is no conflict between the existing data and this model. The Dalitz plot distribution of {eta} {yields} {pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} is discussed under various assumptions about the properties of the interaction responsible for the decay. (auth)

  13. Differential cross sections for the reactions gamma p-> p eta and gamma p -> p eta-prime

    SciTech Connect

    M. Williams, Z. Krahn, D. Applegate, M. Bellis, C.A. Meyer, for the CLAS Collaboration

    2009-10-01

    High-statistics differential cross sections for the reactions gamma p -> p eta and gamma p -> p eta-prime have been measured using the CLAS at Jefferson Lab for center-of-mass energies from near threshold up to 2.84 GeV. The eta-prime results are the most precise to date and provide the largest energy and angular coverage. The eta measurements extend the energy range of the world's large-angle results by approximately 300 MeV. These new data, in particular the eta-prime measurements, are likely to help constrain the analyses being performed to search for new baryon resonance states.

  14. Glue content and mixing angle of the {eta}-{eta}{sup '} system: The effect of the isoscalar 0{sup -} continuum

    SciTech Connect

    Nasrallah, N.F.

    2004-12-01

    Masses and topological charges of the {eta} and {eta}{sup '} mesons are expressed in terms of the singlet-octet mixing angle {theta}. Contributions of the pseudoscalar 0{sup -} continuum are evaluated in a model independent way. Applications to the decay {eta}{yields}3{pi} and to the radiative decay of vector mesons involving {eta} and {eta}{sup '} are considered. Agreement with experiment is, in general, good and the results quite stable for -30.5 deg. < or approx. {theta} < or approx. -18.5 deg.

  15. etas_solve: A robust program to estimate the ETAS parameters

    NASA Astrophysics Data System (ADS)

    Yagi, Y.; Kasahara, A.

    2015-12-01

    The epidemic-type aftershock sequence (ETAS) model introduced by Ogata (1988) has been widely used to quantitatively describe seismicity (e.g. Ogata, 1992; Llenos et al., 2009). However, only a few programs for estimation of the ETAS parameters are publicly available, and it is difficult to automatically apply some of them to observed data due to initial value dependence (e.g. Ogata, 2006). A robust ETAS estimation program is required to meet the recent enhancement of earthquake catalogs. In this study, we developed a new program, etas_solve, that is based on Newton's method and calculates exact gradient and Hessian by using the automatic differentiation technique (Griewank, 1989). The program also supports auxiliary window in time and magnitude (Wang et al., 2010).To demonstrate robustness of the developed program, we tested the dependence of estimated parameters on the choice of initial value by running the program from 1,024 randomly chosen initial values, and then compared the results with that of SAPP (Ogata 2006). We used aftershock data of 26th July 2003 earthquake of M6.2 at the northern Miyagi japan, which is shipped with SAPP, as a testing data. We found that estimation values with etas_solve were independent of the initial value for the testing data, while that with SAPP were varied with the initial value. Although there was initial value dependence in the SAPP's results, the estimated values by SAPP with small (≤10-5) gradient coincided with the solution by etas_solve. etas_solve took longer computation time per iteration than SAPP due to the exact Hessian calculation, but total execution time was comparable to that of SAPP since less number of iterations for convergence was required. In addition, etas_solve was faster than SAPP on multicore machines (around 8-fold speed up with a 16 core machine) since etas_solve is parallelized by OpenMP.etas_solve is written in Fortran and distributed under GNU General Public License at https

  16. FINAL REPORT DE-FG02-04ER41317 Advanced Computation and Chaotic Dynamics for Beams and Accelerators

    SciTech Connect

    Cary, John R

    2014-09-08

    During the year ending in August 2013, we continued to investigate the potential of photonic crystal (PhC) materials for acceleration purposes. We worked to characterize acceleration ability of simple PhC accelerator structures, as well as to characterize PhC materials to determine whether current fabrication techniques can meet the needs of future accelerating structures. We have also continued to design and optimize PhC accelerator structures, with the ultimate goal of finding a new kind of accelerator structure that could offer significant advantages over current RF acceleration technology. This design and optimization of these requires high performance computation, and we continue to work on methods to make such computation faster and more efficient.

  17. The ETA-II induction linac as a high-average-power FEL driver

    NASA Astrophysics Data System (ADS)

    Nexsen, W. E.; Atkinson, D. P.; Barrett, D. M.; Chen, Y.-J.; Clark, J. C.; Griffith, L. V.; Kirbie, H. C.; Newton, M. A.; Paul, A. C.; Sampayan, S.; Throop, A. L.; Turner, W. C.

    1990-10-01

    The Experimental Test Accelerator II (ETA-II) is the first induction linac designed specifically to FEL requirements. It is primarily intended to demonstrate induction accelerator technology for high-average-power, high-brightness electron beams, and will be used to drive a 140 and 250 GHz microwave FEL for plasma heating experiments in the Microwave Tokamak Experiment (MTX) at LLNL. Its features include high-vacuum design which allows the use of an intrinsically bright dispenser cathode, induction cells designed to minimize BBU growth rate, and careful attention to magnetic alignment to minimize radial sweep due to beam corkscrew. The use of magnetic switches allows high-average-power operation. At present ETA-II is being used to drive 140 GHz plasma heating experiments. These experiments require nominal beam parameters of 6 MeV energy, 2 kA current, 20 ns pulse width and a brightness of 1 × 108 A/(m rad)2 at the wiggler with a pulse repetition frequency (prf) of 0.5 Hz. Future 250 GHz experiments require beam parameters of 10 MeV energy, 3 kA current, 50 ns pulse width and a brightness of 1 × 108 A/(m rad)2 with a 5 kHz prf for 0.5 s. In this paper we discuss the present status of ETA-II parameters and the phased development program necessary to satisfy these future requirements.

  18. Physics and Outlook for Rare, All-neutral Eta Decays

    SciTech Connect

    Mack, David J.

    2014-06-01

    The $\\eta$ meson provides a laboratory to study isospin violation and search for new flavor-conserving sources of C and CP violation with a sensitivity approaching $10^{-6}$ of the isospin-conserving strong amplitude. Some of the most interesting rare $\\eta$ decays are the neutral modes, yet the effective loss of photons from the relatively common decay $\\eta \\rightarrow 3\\pi^0 \\rightarrow 6\\gamma$ (33$\\%$) has largely limited the sensitivity for decays producing 3-5$\\gamma$'s. Particularly important relevant branches include the highly suppressed $\\eta \\rightarrow \\pi^0 2\\gamma \\rightarrow 4\\gamma$, which provides a rare window on testing models of $O(p^6)$ contributions in ChPTh, and $\\eta \\rightarrow 3\\gamma$ and $\\eta \\rightarrow 2\\pi^0 \\gamma \\rightarrow 5\\gamma$ which provide direct constraints on C violation in flavor-conserving processes. The substitution of lead tungstate in the forward calorimeter of the GluEx setup in Jefferson Lab's new Hall D would allow dramatically improved measurements. The main niche of this facility, which we call the JLab Eta Factory (JEF), would be $\\eta$ decay neutral modes. However, this could likely be expanded to rare $\\eta'(958)$ decays for low energy QCD studies as well as $\\eta$ decays involving muons for new physics searches.

  19. Eta-mesic nuclei: Past, present, future

    SciTech Connect

    Haider, Q.; Liu, Lon -Chang

    2015-09-23

    Eta-mesic nucleus or the quasibound nuclear state of an eta (η) meson in a nucleus is caused by strong interaction force alone. This new type of nuclear species, which extends the landscape of nuclear physics, has been extensively studied since its prediction in 1986. We review and analyze in great detail the models of the fundamental η–nucleon interaction leading to the formation of an η–mesic nucleus, the methods used in calculating the properties of a bound η, and the approaches employed in the interpretation of the pertinent experimental data. In view of the successful observation of the η–mesic nucleus 25Mgη and other promising experimental results, future direction in searching for more η–mesic nuclei is suggested.

  20. Eta-mesic nuclei: Past, present, future

    DOE PAGESBeta

    Haider, Q.; Liu, Lon -Chang

    2015-09-23

    Eta-mesic nucleus or the quasibound nuclear state of an eta (η) meson in a nucleus is caused by strong interaction force alone. This new type of nuclear species, which extends the landscape of nuclear physics, has been extensively studied since its prediction in 1986. We review and analyze in great detail the models of the fundamental η–nucleon interaction leading to the formation of an η–mesic nucleus, the methods used in calculating the properties of a bound η, and the approaches employed in the interpretation of the pertinent experimental data. In view of the successful observation of the η–mesic nucleus 25Mgηmore » and other promising experimental results, future direction in searching for more η–mesic nuclei is suggested.« less

  1. HUBBLE SHOWS EXPANSION OF ETA CARINAE DEBRIS

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The furious expansion of a huge, billowing pair of gas and dust clouds are captured in this NASA Hubble Space Telescope comparison image of the supermassive star Eta Carinae. To create the picture, astronomers aligned and subtracted two images of Eta Carinae taken 17 months apart (April 1994, September 1995). Black represents where the material was located in the older image, and white represents the more recent location. (The light and dark streaks that make an 'X' pattern are instrumental artifacts caused by the extreme brightness of the central star. The bright white region at the center of the image results from the star and its immediate surroundings being 'saturated' in one of the images.)Photo Credit: Jon Morse (University of Colorado), Kris Davidson (University of Minnesota), and NASA Image files in GIF and JPEG format and captions may be accessed on Internet via anonymous ftp from oposite.stsci.edu in /pubinfo.

  2. UCLA Intermediate Energy Nuclear and Particle Physics Research: Final Report

    SciTech Connect

    Nefkens, B M.K.; Goetz, J; Lapik, A; Korolija, M; Prakhov, S; Starostin, A

    2011-05-18

    This project covers the following research: (a) Investigations into the structure of the proton and neutron. This is done by investigating the different resonance states of nucleons with beams of tagged, polarized photons, linearly as well as circularly, incident on polarized hydrogen/deuterium targets and measuring the production of {pi}{sup 0}, 2{pi}{sup }0, 3{pi}{sup 0}, {eta} , {eta}', {omega}, etc. The principal detector is the Crystal Ball multiphoton spectrometer which has an acceptance of nearly 4 . It has been moved to the MAMI accelerator facility of the University of Mainz, Germany. We investigate the conversion of electromagnetic energy into mesonic matter and conversely. (b) We investigate the consequences of applying the "standard" symmetries of isospin, G-parity, charge conjugation, C, P, T, and chirality using rare and forbidden decays of light mesons such as the {eta} ,{eta}' and {omega}. We also investigate the consequences of these symmetries being slightly broken symmetries. We do this by studying selected meson decays using the Crystal Ball detector. (c) We determine the mass, or more precisely the mass difference of the three light quarks (which are inputs to Quantum Chromodynamics) by measuring the decay rate of specially selected {eta} and {eta}' decay modes, again we use the Crystal Ball. (d)We have started a new program to search for the 33 missing cascade baryons using the CLAS detector at the Thomas Jefferson Laboratory. Cascade resonances are very special: they have double strangeness and are quite narrow. This implies that they can be discovered by the missing mass technique in photoproduction reactions such as in {gamma}p{yields}{Xi}{sup}K{sup +}K{sup +}. The cascade program is of particular importance for the upgrade to 12 GeV of the CLAS detector and for design of the Hall D at JLab. (e) Finally, we are getting more involved in a new program to measure the hadronic matter form factor of complex nuclei, in particular the "neutron

  3. Eta Carinae and Other Luminous Blue Variables

    NASA Technical Reports Server (NTRS)

    Corcoran, M. F.

    2006-01-01

    Luminous Blue Variables (LBVs) are believed to be evolved, extremely massive stars close to the Eddington Limit and hence prone to bouts of large-scale, unstable mass loss. I discuss current understanding of the evolutionary state of these objects, the role duplicity may play and known physical characteristics of these stars using the X-ray luminous LBVs Eta Carinae and HD 5980 as test cases.

  4. Measurements of the branching fractions of exclusive charmless B meson decays with eta(') or omega mesons.

    PubMed

    Aubert, B; Boutigny, D; Gaillard, J M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Palano, A; Chen, G P; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Reinertsen, P L; Stugu, B; Abbott, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Clark, A R; Gill, M S; Gritsan, A; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kluth, S; Kolomensky, Y G; Kral, J F; LeClerc, C; Levi, M E; Liu, T; Lynch, G; Meyer, A B; Momayezi, M; Oddone, P J; Perazzo, A; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Bright-Thomas, P G; Harrison, T J; Hawkes, C M; Knowles, D J; O'Neale, S W; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Krug, J; Kunze, M; Lewandowski, B; Peters, K; Schmuecker, H; Steinke, M; Andress, J C; Barlow, N R; Bhimji, W; Chevalier, N; Clark, P J; Cottingham, W N; De Groot, N; Dyce, N; Foster, B; McFall, J D; Wallom, D; Wilson, F F; Abe, K; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Jolly, S; McKemey, A K; Tinslay, J; Blinov, V E; Bukin, A D; Bukin, D A; Buzykaev, A R; Golubev, V B; Ivanchenko, V N; Korol, A A; Kravchenko, E A; Onuchin, A P; Salnikov, A A; Serednyakov, S I; Skovpen, Y I; Telnov, V I; Yushkov, A N; Best, D; Lankford, A J; Mandelkern, M; McMahon, S; Stoker, D P; Ahsan, A; Arisaka, K; Buchanan, C; Chun, S; Branson, J G; MacFarlane, D B; Prell, S; Rahatlou, S; Raven, G; Sharma, V; Campagnari, C; Dahmes, B; Hart, P A; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Richman, J D; Verkerke, W; Witherell, M; Yellin, S; Beringer, J; Dorfan, D E; Eisner, A M; Frey, A; Grillo, A A; Grothe, M; Heusch, C A; Johnson, R P; Kroeger, W; Lockman, W S; Pulliam, T; Sadrozinski, H; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Metzler, S; Oyang, J; Porter, F C; Ryd, A; Samuel, A; Weaver, M; Yang, S; Zhu, R Y; Devmal, S; Geld, T L; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Barillari, T; Bloom, P; Dima, M O; Fahey, S; Ford, W T; Hall, T L; Johnson, D R; Nauenberg, U; Olivas, A; Park, H; Rankin, P; Roy, J; Sen, S; Smith, J G; van Hoek, W C; Wagner, D L; Blouw, J; Harton, J L; Krishnamurthy, M; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Brandt, T; Brose, J; Colberg, T; Dahlinger, G; Dickopp, M; Dubitzky, R S; Maly, E; Müller-Pfefferkorn, R; Otto, S; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Behr, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Ferrag, S; Roussot, E; T'Jampens, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Anjomshoaa, A; Bernet, R; Khan, A; Muheim, F; Playfer, S; Swain, J E; Falbo, M; Borean, C; Bozzi, C; Dittongo, S; Folegani, M; Piemontese, L; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Xie, Y; Zallo, A; Bagnasco, S; Buzzo, A; Contri, R; Crosetti, G; Fabbricatore, P; Farinon, S; Lo Vetere, M; Macri, M; Monge, M R; Musenich, R; Pallavicini, M; Parodi, R; Passaggio, S; Pastore, F C; Patrignani, C; Pia, M G; Priano, C; Robutti, E; Santroni, A; Morii, M; Bartoldus, R; Dignan, T; Hamilton, R; Mallik, U; Cochran, J; Crawley, H B; Fischer, P A; Lamsa, J; Meyer, W T; Rosenberg, E I; Benkebil, M; Grosdidier, G; Hast, C; Höcker, A; Lacker, H M; LePeltier, V; Lutz, A M; Plaszczynski, S; Schune, M H; Trincaz-Duvoid, S; Valassi, A; Wormser, G; Bionta, R M; Brigljević, V; Lange, D J; Mugge, M; Shi, X; van Bibber, K; Wenaus, T J; Wright, D M; Wuest, C R; Carroll, M; Fry, J R; Gabathuler, E; Gamet, R; George, M; Kay, M; Payne, D J; Sloane, R J; Touramanis, C; Aspinwall, M L; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Gunawardane, N J; Nash, J A; Sanders, P; Smith, D; Azzopardi, D E; Back, J J; Dixon, P; Harrison, P F; Potter, R J; Shorthouse, H W; Strother, P; Vidal, P B; Williams, M I; Cowan, G; George, S; Green, M G; Kurup, A; Marker, C E; McGrath, P; McMahon, T R; Ricciardi, S; Salvatore, F; Scott, I; Vaitsas, G; Brown, D; Davis, C L; Allison, J; Barlow, R J; Boyd, J T; Forti, A C; Fullwood, J; Jackson, F; Lafferty, G D; Savvas, N; Simopoulos, E T; Weatherall, J H; Farbin, A; Jawahery, A; Lillard, V; Olsen, J; Roberts, D A; Schieck, J R; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Moore, T B; Staengle, H; Willocq, S; Brau, B; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Milek, M; Patel, P M; Trischuk, J; Lanni, F; Palombo, F; Bauer, J M; Booke, M; Cremaldi, L; Eschenburg, V; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Martin, J P; Nief, J Y; Seitz, R; Taras, P; Zacek, V; Nicholson, H; Sutton, C S; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; LoSecco, J M; Alsmiller, J R; Gabriel, T A; Handler, T; Brau, J; Frey, R; Iwasaki, M; Sinev, N B; Strom, D; Colecchia, F; Dal Corso, F; Dorigo, A; Galeazzi, F; Margoni, M; Michelon, G; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Torassa, E; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; De la Vaissière, C; Del Buono, L; Hamon, O; Le Diberder, F; Leruste, P; Lory, J; Roos, L; Stark, J; Versillé, S; Manfredi, P F; Re, V; Speziali, V; Frank, E D; Gladney, L; Guo, Q H; Panetta, J H; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Simi, G; Triggiani, G; Walsh, J; Haire, M; Judd, D; Paick, K; Turnbull, L; Wagoner, D E; Albert, J; Bula, C; Elmer, P; Lu, C; McDonald, K T; Miftakov, V; Schaffner, S F; Smith, A J; Tumanov, A; Varnes, E W; Cavoto, G; del Re, D; Faccini, R; Ferrarotto, F; Ferroni, F; Fratini, K; Lamanna, E; Leonardi, E; Mazzoni, M A; Morganti, S; Piredda, G; Safai Tehrani, F; Serra, M; Voena, C; Christ, S; Waldi, R; Adye, T; Franek, B; Geddes, N I; Gopal, G P; Xella, S M; Aleksan, R; De Domenico, G; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; London, G W; Mayer, B; Serfass, B; Vasseur, G; Yeche, C; Zito, M; Copty, N; Purohit, M V; Singh, H; Yumiceva, F X; Adam, I; Anthony, P L; Aston, D; Baird, K; Bloom, E; Boyarski, A M; Bulos, F; Calderini, G; Claus, R; Convery, M R; Coupal, D P; Coward, D H; Dorfan, J; Doser, M; Dunwoodie, W; Field, R C; Glanzman, T; Godfrey, G L; Gowdy, S J; Grosso, P; Himel, T; Huffner, M E; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocain, M L; Langenegger, U; Leith, D W; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Menke, S; Messner, R; Moffeit, K C; Mount, R; Muller, D R; O'Grady, C P; Perl, M; Petrak, S; Quinn, H; Ratcliff, B N; Robertson, S H; Rochester, L S; Roodman, A; Schietinger, T; Schindler, R H; Schwiening, J; Serbo, V V; Snyder, A; Soha, A; Spanier, S M; Stelzer, J; Su, D; Sullivan, M K; Tanaka, H A; Va'vra, J; Wagner, S R; Weinstein, A J; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Cheng, C H; Kirkby, D; Meyer, T I; Roat, C; Henderson, R; Bugg, W; Cohn, H; Weidemann, A W; Izen, J M; Kitayama, I; Lou, X C; Turcotte, M; Bianchi, F; Bona, M; Di Girolamo, B; Gamba, D; Smol, A; Zanin, D; Lanceri, L; Pompili, A; Vaugnin, G; Panvini, R S; Brown, C M; De Silva, A; Kowalewski, R; Roney, J M; Band, H R; Charles, E; Dasu, S; Di Lodovico, F; Eichenbaum, A M; Hu, H; Johnson, J R; Liu, R; Nielsen, J; Pan, Y; Prepost, R; Scott, I J; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, S L; Yu, Z; Zobernig, H; Kordich, T M; Neal, H

    2001-11-26

    We present the results of searches for B decays to charmless two-body final states containing eta(') or omega mesons, based on 20.7 fb(-1) of data collected with the BABAR detector. We find the branching fractions Beta(B(+)-->eta(')K(+)) = (70+/-8+/-5) x 10(-6), Beta(B(0)-->eta(')K(0)) = (42(+13)(-11) +/- 4) x 10(-6), and Beta(B(+)-->omega pi(+)) = (6.6(+2.1)(-1.8) +/- 0.7) x 10(-6), where the first error quoted is statistical and the second is systematic. We give measurements of four additional modes for which the 90% confidence level upper limits are Beta(B(+)-->eta(')pi(+)) < 12 x 10(-6), Beta(B(+)-->omega K(+)) < 4 x 10(-6), Beta(B(0)-->omega K(0)) < 13 x 10(-6), and Beta(B(0)-->omega pi(0)) < 3 x 10(-6). PMID:11736395

  5. The radio source around Eta Carinae

    NASA Technical Reports Server (NTRS)

    White, S. M.; Duncan, R. A.; Lim, J.; Nelson, G. J.; Drake, S. A.; Kundu, M. R.

    1994-01-01

    We present high spatial resolution radio observations of the peculiar southern star Eta Carinae, made with the Australian Telescope. The images, at 8 and 9 GHz with a resolution of 1.0 arcsec show a source of dimension 10 arcsec and total flux of 0.7 Jy dominated by a strong central peak. The radio emission is unpolarized and offers no support to models which invoke degenerate stars or more exotic objects within the core of Eta Car. In these data we find no evidence for more than one energy source in the core with arcsecond separations as some infrared observations have suggested. Several levels of structure are evident in the radio image, which shows symmetry on the larger scales. Conventional formulae for stellar wind radio sources give a mass loss rate of order 3 x 10(exp -4) Solar Mass/yr based on the radio flux in the central peak, which yields a wind momentum flux of order 20% of the momentum flux available from the star's radiation field. The radio emission at these frequencies is consistent with thermal emission from gas flowing away from a 'luminous blue variable' star (LBV) Eta Car is probably the brightest thermal stellar wind radio source in the sky.

  6. Interaction of eta mesons with nuclei.

    PubMed

    Kelkar, N G; Khemchandani, K P; Upadhyay, N J; Jain, B K

    2013-06-01

    Back in the mid-1980s, a new branch of investigation related to the interaction of eta mesons with nuclei came into existence. It started with the theoretical prediction of possible exotic states of eta mesons and nuclei bound by the strong interaction and later developed into an extensive experimental program to search for such unstable states as well as understand the underlying interaction via eta-meson producing reactions. The vast literature of experimental as well as theoretical works that studied various aspects of eta-producing reactions such as the π(+)n → ηp, pd → (3)Heη, p (6)Li → (7)Be η and γ (3)He → η X, to name a few, had but one objective in mind: to understand the eta-nucleon (ηN) and hence the η-nucleus interaction which could explain the production data and confirm the existence of some η-mesic nuclei. In spite of these efforts, there remain uncertainties in the knowledge of the ηN and hence the η-nucleus interaction. Therefore, this review is an attempt to bind together the findings in these works and draw some global and specific conclusions which can be useful for future explorations.The ηN scattering length (which represents the strength of the η-nucleon interaction) using different theoretical models and analyzing the data on η production in pion, photon and proton induced reactions was found to be spread out in a wide range, namely, 0.18 ≤ Re aηN ≤ 1.03 fm and 0.16 ≤ Rm aηN ≤ 0.49 fm. Theoretical searches of heavy η-mesic nuclei based on η-nucleus optical potentials and lighter ones based on Faddeev type few-body approaches predict the existence of several quasibound and resonant states. Although some hints of η-mesic states such as (3)(η)He and (25)(η)Mg do exist from previous experiments, the promise of clearer signals for the existence of η-mesic nuclei lies in the experiments to be performed at the J-PARC, MAMI and COSY facilities in the near future. This review is aimed at giving an overall status

  7. Induction linear accelerator for the free-electron laser

    NASA Astrophysics Data System (ADS)

    1986-12-01

    A new design for an induction accelerator for FELs is proposed. The operation of the accelerator, which is based on Faraday's laws, is discussed. The use of an oxide or a dispenser cathode for the high-brightness injector of the accelerator is examined. The designs of the induction cells and nonlinear magnetic pulse compressor for the FELs are described. Ten induction cells form an induction module that is driven by the nonlinear magnetic pulse generator. An experimental test accelerator (ETA) has been developed and is being tested. Diagrams of the injector, induction cell, nonlinear magnetic pulse generator, and the ETA are presented.

  8. Charmless B{yields}K{sub h{eta}}{sup (')} decays with K{sub h}=K, K{sup *}, K{sub 0}{sup *}(1430), K{sub 2}{sup *}(1430)

    SciTech Connect

    Cheng, Hai-Yang; Chua, Chun-Khiang

    2010-08-01

    ) |f{sub {eta}}{sup 's}|>|f{sub {eta}}{sup s}| and (ii) a destructive (constructive) interference between type-I and type-II penguin diagrams for K{sub 2}{sup *{eta}} (K{sub 2}{sup *{eta}'}). However, the predicted rates of B{yields}K{sub 2}{sup *{eta}(')} in naive factorization are too small by 1 order of magnitude and this issue remains to be resolved. There are two K{sup (*){eta}(')} modes in which direct CP asymmetries have been measured with significance around 4{sigma}: A{sub CP}(K{sup -}{eta})=-0.37{+-}0.09 and A{sub CP}(K{sup *0}{eta})=0.19{+-}0.05. In QCDF, power corrections from penguin annihilation which are needed to resolve CP puzzles in K{sup -}{pi}{sup +} and {pi}{sup +}{pi}{sup -} modes will flip A{sub CP}(K{sup -}{eta}) into a wrong sign. We show that soft corrections to the color-suppressed tree amplitude a{sub 2} in conjunction with the charm content of the {eta} will finally lead to A{sub CP}(K{sup -}{eta})=-0.15{sub -0.28}{sup +0.19}. Likewise, this power correction is needed to improve the prediction for A{sub CP}(K{sup *0{eta}}).

  9. Measurement of the gamma gamma* --> eta and gamma gamma* --> eta' transition form factors

    SciTech Connect

    del Amo Sanchez et al, P.

    2011-02-07

    We study the reactions e{sup +}e{sup -} {yields} e{sup +}e{sup -} {eta}{sup (/)} in the single-tag mode and measure the {gamma}{gamma}* {yields} {eta}{sup (/)} transition form factors in the momentum transfer range from 4 to 40 GeV{sup 2}. The analysis is based on 469 fb{sup -1} of integrated luminosity collected at PEP-II with the BABAR detector at e{sup +}e{sup -} center-of-mass energies near 10.6 GeV.

  10. Short-term foreshocks in Southern California and Italy revisited: Observed deviations from the Epidemic-Type Aftershock Sequence (ETAS) Model

    NASA Astrophysics Data System (ADS)

    Seif, Stefanie; Mignan, Arnaud; Wiemer, Stefan

    2013-04-01

    Numerous studies have suggested that short-term foreshocks observed prior to large earthquakes are undistinguishable from the normal behaviour of seismicity, which is well described for example by the Epidemic-Type Aftershock Sequence (ETAS) model. Here we show that these studies fail to extract abnormal foreshock behaviour due to the much more frequent occurrence of aftershocks in comparison to potential foreshocks, which results in undervaluing the role of foreshocks. We first define mainshocks as earthquakes of magnitude M6+ and use a space-time-magnitude window method with a maximum distance of 10 km to the mainshock, a maximum time range of 3 days before the mainshock and a minimum magnitude M4+ to define foreshocks in Southern California and in Italy. We then compare the observed rate of foreshock-mainshock pairs to the rate expected by ETAS simulations. Similar to previous studies, these results indicate that the foreshock activity observed in real catalogues is compatible with the ETAS model. Definition of foreshocks with a window method is, however, simplistic, since any individual event may be considered a foreshock although it is impossible to distinguish a foreshock from background or aftershock activity at a one-to-one event basis. We extend our foreshock analysis based on the predictions of the Non-Critical Precursory Accelerating Seismicity Theory (NC PAST), which are: (1) foreshocks are due to overloading on the main fault and occur in clusters, the activity of which is significantly higher than background activity, (2) microseismicity (M<3) must be included for the emergence of a reliable signal and (3) foreshocks are not systematic before large earthquakes due to aleatoric uncertainty on the rupture process. Following these guidelines, we systematically investigate foreshock sequences before large earthquakes (M6+) in Southern California and Italy. Using different approaches, we finally show that significant anomalies are observed before some

  11. Final Report on "Development and Testing of Advanced Accelerator Structures and Technologies at 11.424 GHz"

    SciTech Connect

    Gold, Steven H.

    2013-10-13

    This is the final report on the research program ?Development and Testing of Advanced Accelerator Structures and Technologies at 11.424 GHz,? which was carried out by the Naval Research Laboratory (NRL) under Interagency Agreement DE?AI02?01ER41170 with the Department of Energy. The period covered by this report is 15 July 2010 ? 14 July 2013. The program included two principal tasks. Task 1 involved a study of the key physics issues related to the use of high gradient dielectric-loaded accelerating (DLA) structures in rf linear accelerators and was carried out in collaboration with Argonne National Laboratory (ANL) and Euclid Techlabs LLC. Task 2 involved a study of high power active microwave pulse compressors and was carried out in collaboration with Omega-P, Inc. and the Institute of Applied Physics of the Russian Academy of Sciences in Nizhny Novgorod. The studies under Task 1 were focused on rf-induced multipactor and breakdown in externally driven DLA structures at the 200-ns timescale. Suppression of multipactor and breakdown are essential to the practical application of dielectric structures in rf linear accelerators. The structures that were studied were developed by ANL and Euclid Techlabs and their performance was evaluated at high power in the X-band Magnicon Laboratory at NRL. Three structures were designed, fabricated, and tested, and the results analyzed in the first two years of the program: a clamped quartz traveling-wave (TW) structure, a externally copper-coated TW structure, and an externally copper-coated dielectric standing-wave (SW) structure. These structures showed that rf breakdown could be largely eliminated by eliminating dielectric joints in the structures, but that the multipactor loading was omnipresent. In the third year of the program, the focus of the program was on multipactor suppression using a strong applied axial magnetic field, as proposed by Chang et al. [C. Chang et al., J. Appl. Phys. 110, 063304 (2011).], and a

  12. Final report to US Department of Energy: Cyclotron autoresonance accelerator for electron beam dry scrubbing of flue gases

    SciTech Connect

    Hirshfield, J.L.

    2001-05-25

    Several designs have been built and operated of microwave cyclotron autoresonance accelerators (CARA's) with electron beam parameters suitable for remediation of pollutants in flue gas emissions from coal-burning power plants. CARA designs have also been developed with a TW-level 10.6 micron laser driver for electron acceleration from 50 to 100 MeV, and with UHF drivers for proton acceleration to over 500 MeV. Dose requirements for reducing SO2, NOx, and particulates in flue gas emissions to acceptable levels have been surveyed, and used to optimize the design of an electron beam source to deliver this dose.

  13. Spectrophotometric Evolution of Eta Carinae's Great Eruption

    NASA Astrophysics Data System (ADS)

    Rest, Armin; Prieto, Jose Luis; Bianco, Federica; Matheson, Thomas; Smith, Nathan; Smith, Chris; Chornock, Ryan; Sinnott, Brendan; Welch, Douglas; Walborn, Nolan

    2013-06-01

    Eta Carinae is one of the most massive binaries in the Milky Way, and its expanding circumstellar nebula has been studied in detail. It was seen as the second brightest star in the sky during its 1800s "Great Eruption", but only visual estimates of its brightness were recorded. We discovered light echoes of the Great Eruption, which allowed us to obtain a spectrum of this event now, 150 years after it was first observed. We will present our new follow-up observations with which we have started to retrace its spectrophotometric evolution during and before the eruption.

  14. Software Users Manual (SUM): Extended Testability Analysis (ETA) Tool

    NASA Technical Reports Server (NTRS)

    Maul, William A.; Fulton, Christopher E.

    2011-01-01

    This software user manual describes the implementation and use the Extended Testability Analysis (ETA) Tool. The ETA Tool is a software program that augments the analysis and reporting capabilities of a commercial-off-the-shelf (COTS) testability analysis software package called the Testability Engineering And Maintenance System (TEAMS) Designer. An initial diagnostic assessment is performed by the TEAMS Designer software using a qualitative, directed-graph model of the system being analyzed. The ETA Tool utilizes system design information captured within the diagnostic model and testability analysis output from the TEAMS Designer software to create a series of six reports for various system engineering needs. The ETA Tool allows the user to perform additional studies on the testability analysis results by determining the detection sensitivity to the loss of certain sensors or tests. The ETA Tool was developed to support design and development of the NASA Ares I Crew Launch Vehicle. The diagnostic analysis provided by the ETA Tool was proven to be valuable system engineering output that provided consistency in the verification of system engineering requirements. This software user manual provides a description of each output report generated by the ETA Tool. The manual also describes the example diagnostic model and supporting documentation - also provided with the ETA Tool software release package - that were used to generate the reports presented in the manual

  15. Hubble Space Telescope imaging of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Hester, J. J.; Westphal, James A.; Light, Robert M.; Currie, Douglas G.; Groth, Edward J.

    1991-01-01

    New high spatial resolution observations of the material around Eta Carinae, obtained with the Hubble Space Telescope Wide Field/Planetary Camera, are presented. The star Eta Carinae is one of the most massive and luminous stars in the Galaxy, and has been episodically expelling significant quantities of gas over the last few centuries. The morphology of the bright central nebulosity (the homunculus) indicates that it is a thin shell with very well defined edges, and is clumpy on 0.2 arcsec (about 10 to the 16th cm) scales. An extension to the northeast of the star (NN/NS using Walborn's 1976 nomenclature) appears to be a stellar jet and its associated bow shock. The bow shock is notable for an intriguing series of parallel linear features across its face. The S ridge and the W arc appear to be part of a 'cap' of emission located to the SW and behind the star. Together, the NE jet and the SW cap suggest that the symmetry axis for the system runs NE-SW rather than SE-NW, as previously supposed. Overall, the data indicate that the material around the star may represent an oblate shell with polar blowouts, rather than a bipolar flow.

  16. A LIGHTHOUSE EFFECT IN ETA CARINAE

    SciTech Connect

    Madura, Thomas I.; Groh, Jose H.

    2012-02-20

    We present a new model for the behavior of scattered time-dependent, asymmetric near-UV emission from the nearby ejecta of {eta} Car. Using a three-dimensional (3D) hydrodynamical simulation of {eta} Car's binary colliding winds, we show that the 3D binary orientation derived by Madura et al. in 2012 is capable of explaining the asymmetric near-UV variability observed in the Hubble Space Telescope Advanced Camera for Surveys/High Resolution Camera F220W images of Smith et al.. Models assuming a binary orientation with i Almost-Equal-To 130 Degree-Sign -145 Degree-Sign , {omega} Almost-Equal-To 230 Degree-Sign -315 Degree-Sign , P.A.{sub z} Almost-Equal-To 302 Degree-Sign -327 Degree-Sign are consistent with the observed F220W near-UV images. We find that the hot binary companion does not significantly contribute to the near-UV excess observed in the F220W images. Rather, we suggest that a bore-hole effect and the reduction of Fe II optical depths inside the wind-wind collision cavity carved in the extended photosphere of the primary star lead to the time-dependent directional illumination of circumbinary material as the companion moves about in its highly elliptical orbit.

  17. Far UV Spectroscopy of eta Carinae

    NASA Technical Reports Server (NTRS)

    Iping, R. C.; Sonneborn, G.; Massa, D.; Hutchings, J. B.; Gull, T. R.; Fisher, Richard (Technical Monitor)

    2000-01-01

    We present the first high spectral resolution observations of the Luminous Blue Variable eta Carinae between the Lyman limit and 1180 Angstroms. High resolution spectra (R approximately 20,000) were obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite on Feb. 1 and Mar. 20, 2000. The observations were made with a 30x30 arcsec aperture and includes the entire Homunculus region. However, the spatial extent of the far UV flux is consistent with a point source. With the limited spatial resolution of the FUSE instrument, we can only constrain the far UV emission to be within +/-5 arcsec of the star. The far UV spectrum of eta Car is dominated by strong absorption features of molecular hydrogen. The observed flux level at 1150 Angstroms is approximately 4\\times 10(exp 12) erg/sq cm/s/Angstrom and decreases approximately linearly to approximately 920 Angstroms where converging HI and HII features completely blanket the spectrum. These observations were obtained as part of the FUSE Early Release Observation program.

  18. MID-CYCLE CHANGES IN ETA CARINAE

    SciTech Connect

    Martin, John C.; Davidson, Kris; Humphreys, Roberta M.; Mehner, Andrea

    2010-05-15

    In late 2006, ground-based photometry of {eta} Car plus the Homunculus showed an unexpected decrease in its integrated apparent brightness, an apparent reversal of its long-term brightening. Subsequent Hubble Space Telescope (HST)/WFPC2 photometry of the central star in the near-UV showed that this was not a simple reversal. This multi-wavelength photometry did not support increased extinction by dust as the explanation for the decrease in brightness. A spectrum obtained with the Gemini Multi-Object Spectrograph on the Gemini-South telescope revealed subtle changes mid-way in {eta} Car's 5.5 yr spectroscopic cycle when compared with HST/Space Telescope Imaging Spectrograph (STIS) spectra at the same phase in the cycle. At mid-cycle the secondary star is 20-30 AU from the primary. We suggest that the spectroscopic changes are consistent with fluctuations in the density and velocity of the primary star's wind, unrelated to the 5.5 yr cycle but possibly related to its latitude-dependent morphology. We also discuss subtle effects that must be taken into account when comparing ground-based and HST/STIS spectra.

  19. Far UV Spectroscopy of eta Carinae

    NASA Technical Reports Server (NTRS)

    Iping, R. C.; Sonneborn, G.; Massa, D. L.; Hutchings, J. B.; Gull, T. R.; Fisher, Richard R. (Technical Monitor)

    2000-01-01

    We present the first high spectral resolution observations of the Luminous Blue Variable eta Carinae between the Lyman limit and 1180 A. High resolution spectra (R approx. 20,000) were obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite on Feb. 1 and Mar. 20, 2000. The observations were made with a 30 x 30 arcsec aperture and includes the entire Homunculus region. However, the spatial extent of the far UV flux is consistent with a point source. With the limited spatial resolution of the FUSE instrument, we can only constrain the far UV emission to be within +/- 5 arcsec of the star. The far UV spectrum of eta Car is dominated by strong absorption features of molecular hydrogen. The observed flux level at 1150A is approx. 4 times 10(exp 12) erg /cm(exp -2) /sec(exp -1) / A(exp -1) and decreases approximately linearly to approx. 920 A where converging H1 and H2 features completely blanket the spectrum. These observations were obtained as part of the FUSE Early Release Observation program.

  20. Hubble Space Telescope imaging of Eta Carinae

    SciTech Connect

    Hester, J.J.; Westphal, J.A.; Light, R.M.; Currie, D.G.; Groth, E.J. Lick Observatory, Santa Cruz, CA Maryland Univ., College Park Princeton Univ., NJ )

    1991-08-01

    New high spatial resolution observations of the material around Eta Carinae, obtained with the Hubble Space Telescope Wide Field/Planetary Camera, are presented. The star Eta Carinae is one of the most massive and luminous stars in the Galaxy, and has been episodically expelling significant quantities of gas over the last few centuries. The morphology of the bright central nebulosity (the homunculus) indicates that it is a thin shell with very well defined edges, and is clumpy on 0.2 arcsec (about 10 to the 16th cm) scales. An extension to the northeast of the star (NN/NS using Walborn's 1976 nomenclature) appears to be a stellar jet and its associated bow shock. The bow shock is notable for an intriguing series of parallel linear features across its face. The S ridge and the W arc appear to be part of a 'cap' of emission located to the SW and behind the star. Together, the NE jet and the SW cap suggest that the symmetry axis for the system runs NE-SW rather than SE-NW, as previously supposed. Overall, the data indicate that the material around the star may represent an oblate shell with polar blowouts, rather than a bipolar flow. 26 refs.

  1. {eta}-Nucleon scattering length and effective range uncertainties

    SciTech Connect

    Green, A.M.; Wycech, S.

    2005-01-01

    The coupled {eta}N, {pi}N, {gamma}N, {pi}{pi}N system is described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to {pi}N{yields}{pi}N, {pi}N{yields}{eta}N, {gamma}N{yields}{pi}N, and {gamma}N{yields}{eta}N data in an energy range of about 100 MeV or so each side of the {eta} threshold. Compared with our earlier analysis, we now utilize recent Crystal Ball data. However, the outcome confirms our previous result that the {eta}-nucleon scattering length a is large with a value of 0.91(6)+i 0.27(2) fm.

  2. Search for non-thermal radio emission from Eta Carina's outer blast wave with ATCA

    NASA Astrophysics Data System (ADS)

    Ohm, Stefan; Urquhart, James; Skilton, Joanna Lucy; Hinton, Jim; Domainko, Wilfried

    2010-10-01

    Non-thermal hard X-ray and high-energy (HE; 1 MeV < E < 100 GeV) gamma-ray emission in the direction of Eta Carina has been recently detected using the INTEGRAL, AGILE and Fermi satellites. This emission can be either interpreted in the framework of particle acceleration in the colliding wind region between the two massive stars or in the very fast moving blast wave which originates in the historical 1843 "Great Eruption". The detection of a radio shell at the location of the shock would support the latter scenario and confirm Eta Carina as prime example of a new source type, namely, an LBV star whose massive ejecta accelerates electrons to non-thermal energies. While Fermi and INTEGRAL do not provide sufficient angular resolution to resolve the blast wave, high resolution radio observations using ATCA will be able to test non-thermal radio emission from this acceleration site. The current sensitivity of ATCA is such that a relatively modest observation time of 12 hours will be sufficient to image the synchrotron emission from the blast region down to magnetic field strengths well below typical ISM values and hence prove or reject our blast-wave hypothesis for the high energy emission.

  3. Chiral corrections to the anomalous 2{gamma} decays of {pi}{sup 0}, {eta} and {eta}{prime}

    SciTech Connect

    Issler, D.

    1990-11-01

    To any order in chiral perturbation theory, the anomalous Wess-Zumino term is shown to generate only chirally invariant counterterms. Explicit examples of 0(p{sub 6}) terms generated by one-loop graphs are given, some of which are relevant to the two-photon decays of {pi}{sup o}, {eta} and {eta}{prime}.

  4. Radiolabeled microsphere technique in conscious subjects during acceleration exposures on the USAFAM centrifuge. Final report, August 1977-November 1978

    SciTech Connect

    Laughlin, M.H.; Jaggars, J.L.

    1980-03-01

    The methods used to apply the radiolabeled microsphere technique for the study of the effects of +Gz acceleration on regional blood flows are presented. A remote-control system designed to infuse suspensions of microspheres into the left atrium on conscious animals is outlined as is a device which allows the remote, sequential withdrawal of six blood samples. Results are presented which demonstrate that the cautious application of the radiolabeled microsphere technique using the outlined systems can produce good information about the effects of +Gz acceleration on regional blood flows.

  5. MTX final report

    SciTech Connect

    Hooper, E.B.; Allen, S.L.; Brown, M.D.; Byers, J.A.; Casper, T.A.; Cohen, B.I.; Cohen, R.H.; Fenstermacher, M.E.; Foote, J.H.; Hoshino, K.

    1994-01-01

    The MTX experiment was proposed in 1986 to apply high frequency microwaves generated by a free-electron laser (FEL) to electron cyclotron resonance heating (ECRH) in a high field, high density tokamak. As the absorption of microwaves at the electron cyclotron resonance requires high frequencies, the opportunity of applying a free-electron laser has appeal as the device is not limited to frequencies in the microwave or long millimeter wavelength regions, in contrast to many other sources. In addition, the FEL is inherently a high power source of microwaves, which would permit single units of 10 MW or more, optimum for reactors. Finally, it was recognized early in the study of the application of the FEL based on the induction linear accelerator, that the nonlinear effects associated with the intense pulses of microwaves naturally generated would offer several unique opportunities to apply ECRH to current drive, MHD control, and other plasma effects. It was consequently decided to adapt the induction accelerator based FEL to heating and controlling the tokamak, and to conduct experiments on the associated physics. To this end, the Alcator C tokamak was moved from the Massachusetts Institute of Technology (MIT) to the Lawrence Livermore National Laboratory where it was installed in Building 431 and operated from March, 1989, until the conclusion of the experiment in October, 1992. The FEL, based on the ETA-11 accelerator and IMP wiggler was brought into operation by the LLNL Electron Beam Group and power injected into the tokamak during an experimental run in the Fall, 1989. Following an upgrade by the MTX group, a second experimental run was made lasting from the Winter, 1992 through the end of the experiment. Significant contributions to the ECRH experiments were made by the Japan Atomic Energy Research Institute (JAERI).

  6. Accelerated screening methods for determining chemical and thermal stability of refrigerant-lubricant mixtures, Part 1: Method assessment. Final report

    SciTech Connect

    Kauffman, R.

    1993-04-01

    This report presents results of a literature search performed to identify analytical techniques suitable for accelerated screening of chemical and thermal stabilities of different refrigerant/lubricant combinations. Search focused on three areas: Chemical stability data of HFC-134a and other non-chlorine containing refrigerant candidates; chemical stability data of CFC-12, HCFC-22, and other chlorine containing refrigerants; and accelerated thermal analytical techniques. Literature was catalogued and an abstract was written for each journal article or technical report. Several thermal analytical techniques were identified as candidates for development into accelerated screening tests. They are easy to operate, are common to most laboratories, and are expected to produce refrigerant/lubricant stability evaluations which agree with the current stability test ANSI/ASHRAE (American National Standards Institute/American Society of Heating, Refrigerating, and Air-Conditioning Engineers) Standard 97-1989, ``Sealed Glass Tube Method to Test the Chemical Stability of Material for Use Within Refrigerant Systems.`` Initial results of one accelerated thermal analytical candidate, DTA, are presented for CFC-12/mineral oil and HCFC-22/mineral oil combinations. Also described is research which will be performed in Part II to optimize the selected candidate.

  7. Structure and mechanism of human DNA polymerase [eta

    SciTech Connect

    Biertümpfel, Christian; Zhao, Ye; Kondo, Yuji; Ramón-Maiques, Santiago; Gregory, Mark; Lee, Jae Young; Masutani, Chikahide; Lehmann, Alan R.; Hanaoka, Fumio; Yang, Wei

    2010-11-03

    The variant form of the human syndrome xeroderma pigmentosum (XPV) is caused by a deficiency in DNA polymerase {eta} (Pol{eta}), a DNA polymerase that enables replication through ultraviolet-induced pyrimidine dimers. Here we report high-resolution crystal structures of human Pol{eta} at four consecutive steps during DNA synthesis through cis-syn cyclobutane thymine dimers. Pol{eta} acts like a 'molecular splint' to stabilize damaged DNA in a normal B-form conformation. An enlarged active site accommodates the thymine dimer with excellent stereochemistry for two-metal ion catalysis. Two residues conserved among Pol{eta} orthologues form specific hydrogen bonds with the lesion and the incoming nucleotide to assist translesion synthesis. On the basis of the structures, eight Pol{eta} missense mutations causing XPV can be rationalized as undermining the molecular splint or perturbing the active-site alignment. The structures also provide an insight into the role of Pol{eta} in replicating through D loop and DNA fragile sites.

  8. Detection of a Hot Binary Companion of eta Carinae

    NASA Technical Reports Server (NTRS)

    Sonneborn, G.; Iping, R. C.; Gull, T. R.; Massa, D.; Hillier, D. J.

    2006-01-01

    A hot companion of eta Carinae has been detected using high resolution spectra (905 - 1 180 Angsroms) obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. Observations were obtained at two epochs of the 2024-day orbit: 2003 June during ingress to the 2003.5 X-ray eclipse and 2004 April several months after egress. These data show that essentially all the far-UV flux from eta Car shortward of Lyman alpha disappeared at least two days before the start of the X-ray eclipse (2003 June 29), implying that the hot companion, eta Car By was also eclipsed by the dense wind or extended atmosphere of eta Car A. Analysis of the far-UV spectrum shows that eta Car B is a luminous hot star. N II 1084-1086 emission disappears at the same time as the far-UV continuum, indicating that this feature originates from eta Car B itself or in close proximity to it. The strong N II emission also raises the possibility that the companion star is nitrogen rich. The observed FUV flux levels and spectral features, combined with the timing of their disappearance, are consistent with eta Carinae being a massive binary system.

  9. Detection of a Hot Binary Companion of eta Carinae

    NASA Technical Reports Server (NTRS)

    Sonnebom, G.; Iping, R. C.; Gull, T. R.; Massa, D. L.; Hillier, D. J.

    2006-01-01

    A hot companion of eta Carinae has been detected using high resolution spectra (905 - 1180 A) obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. Observations were obtained at two epochs of the 2024-day orbit: 2003 June during ingress to the 2003.5 X-ray eclipse and 2004 April several months after egress. These data show that essentially all the far-UV flux from eta Car shortward of Lyman alpha disappeared at least two days before the start of the X-ray eclipse (2003 June 29), implying that the hot companion, eta Car B, was also eclipsed by the dense wind or extended atmosphere of eta Car A. Analysis of the far-UV spectrum shows that eta Car B is a luminous hot star. N II 1084-1086 emission disappears at the same time as the far-UV continuum, indicating that this feature originates from eta Car B itself or in close proximity to it. The strong N II emission also raises the possibility that the companion star is nitrogen rich. The observed FUV flux levels and spectral features, combined with the timing of their disappearance, is consistent with eta Carinae being a massive binary system

  10. The Rapid Brightening of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Martin, John C.; Davidson, Kris; Mehner, Andrea; Humphreys, Roberta M.

    2016-01-01

    Eta Carinae is one of the most dynamic and well-observed massive stars. Its bipolar Homunculus Nebula and other observations imply it has a strong latitude dependent stellar wind. The significant brightening of the star itself over the last two decades has been commonly explained as an evolution of the latitude structure of the wind , change in mass-loss rate, and/or clearing of circumstellar material in our direct line sight. Hubble Space Telescope images (with a much higher spatial resolution than ground-based images) document an increase in contrast between the brightness of the star and the Homunculus reflection nebula. We present measurements of the nebula's brightness, sampling the changing brightness of the star viewed from angles differing from our own direct line of sight. We also present ultraviolet photometry of the star synthesized from recent HST/STIS observations.

  11. Error Sources in the ETA Energy Analyzer Measurement

    SciTech Connect

    Nexsen, W E

    2004-12-13

    At present the ETA beam energy as measured by the ETA energy analyzer and the DARHT spectrometer differ by {approx}12%. This discrepancy is due to two sources, an overestimate of the effective length of the ETA energy analyzer bending-field, and data reduction methods that are not valid. The discrepancy can be eliminated if we return to the original process of measuring the angular deflection of the beam and use a value of 43.2cm for the effective length of the axial field profile.

  12. Estimation of the parameters of ETAS models by Simulated Annealing

    PubMed Central

    Lombardi, Anna Maria

    2015-01-01

    This paper proposes a new algorithm to estimate the maximum likelihood parameters of an Epidemic Type Aftershock Sequences (ETAS) model. It is based on Simulated Annealing, a versatile method that solves problems of global optimization and ensures convergence to a global optimum. The procedure is tested on both simulated and real catalogs. The main conclusion is that the method performs poorly as the size of the catalog decreases because the effect of the correlation of the ETAS parameters is more significant. These results give new insights into the ETAS model and the efficiency of the maximum-likelihood method within this context. PMID:25673036

  13. Solar Technology Acceleration Center (SolarTAC): Cooperative Research and Development Final Report, CRADA Number CRD-07-259

    SciTech Connect

    Kramer, W.

    2011-10-01

    This agreement allowed NREL to serve as an advisor on SolarTAC - a collaborative effort between Xcel Energy, NREL, and the University of Colorado at Boulder. The collaboration was formed to accelerate pre-commercial and early commercial solar energy technologies to the marketplace. Through this CRADA, NREL participated in the deployment of solar energy generation technologies and related solar equipment for research, testing, validation, and demonstration purposes.

  14. Observation of {eta}{sup '} Decays to {pi}{sup +}{pi}{sup -}{pi}{sup 0} and {pi}{sup +}{pi}{sup -}e{sup +}e{sup -}

    SciTech Connect

    Naik, P.; Rademacker, J.; Asner, D. M.; Edwards, K. W.; Reed, J.; Robichaud, A. N.; Tatishvili, G.; Briere, R. A.; Vogel, H.; Onyisi, P. U. E.; Rosner, J. L.; Alexander, J. P.; Cassel, D. G.; Duboscq, J. E.; Ehrlich, R.; Fields, L.; Galik, R. S.; Gibbons, L.; Gray, R.; Gray, S. W.

    2009-02-13

    Using {psi}(2S){yields}{pi}{sup +}{pi}{sup -}J/{psi}, J/{psi}{yields}{gamma}{eta}{sup '} events acquired with the CLEO-c detector at the CESR e{sup +}e{sup -} collider, we make the first observations of the decays {eta}{sup '}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0} and {eta}{sup '}{yields}{pi}{sup +}{pi}{sup -}e{sup +}e{sup -}, measuring absolute branching fractions (37{sub -9}{sup +11}{+-}4)x10{sup -4} and (25{sub -9}{sup +12}{+-}5)x10{sup -4}, respectively. For {eta}{sup '}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0}, this result probes the mechanism of isospin violation and the roles of {pi}{sup 0}/{eta}/{eta}{sup '}-mixing and final state rescattering in strong decays. We also set upper limits on branching fractions for {eta}{sup '} decays to {pi}{sup +}{pi}{sup -}{mu}{sup +}{mu}{sup -}, 2({pi}{sup +}{pi}{sup -}), {pi}{sup +}{pi}{sup -}2{pi}{sup 0}, 2({pi}{sup +}{pi}{sup -}){pi}{sup 0}, 3({pi}{sup +}{pi}{sup -}), and invisible final states.

  15. Minute Temperature Fluctuations Detected in Eta Bootis

    NASA Astrophysics Data System (ADS)

    1994-11-01

    A group of astronomers from the Aarhus University (Denmark) and the European Southern Observatory (2) have for the first time succeeded in detecting solar-type oscillations in another star. They observed the temperature of the bright northern star Eta Bootis during six nights with the 2.5-metre Nordic Optical Telescope at the Roque de los Muchachos observatory on the island of La Palma (Canary Islands) and were able to show that it varies periodically by a few hundredths of a degree. These changes are caused by pressure waves in the star and are directly dependent on its inner structure. A detailed analysis by the astronomers has shown that the observed effects are in good agreement with current stellar models. This is a most important, independent test of stellar theory. The Sun is an Oscillating Star About twenty years ago, it was discovered that the nearest star, our Sun, oscillates like the ringing of a bell with a period of about 5 minutes. The same phenomenon is known in the Earth, which begins to vibrate after earthquakes; in this way seismologists have been able to discern a layered structure in the Earth's interior. The recent impacts of a comet on Jupiter most likely had a similar effect on that planet. The observed solar oscillations concern the entire gaseous body of the Sun, but we can of course only observe them on its surface. It has been found that each mode moves the surface up and down by less than 25 metres; the combined motion is very complicated, because there are many different, simultaneous modes, each of which has a slightly different period. The exact values of these periods are sensitive to the speed of sound in the Sun's interior, which in turn depends on the density of the material there. Thus, by measuring the periods of solar oscillations, we may probe the internal structure of the Sun, that is otherwise inaccessible to observations. Why does the Sun oscillate and what is the cause of these oscillations ? We do not know yet, but it is

  16. {eta} Prime {yields}{pi}{sup 0}{gamma}{gamma} and {eta} Prime {yields}{eta}{gamma}{gamma}: A primer analysis

    SciTech Connect

    Escribano, Rafel

    2012-10-23

    The electromagnetic rare decays {eta} Prime {yields}{pi}{sup 0}{gamma}{gamma} and {eta} Prime {yields}{pi}{sup 0}{gamma}{gamma} are analysed for the first time and their predicted branching ratios given. The vector meson exchange dominant contribution is treated using Vector Meson Dominance and the scalar component is estimated by means of the Linear Sigma Model. The agreement between our calculation and the measurement of the related process {eta} Prime {yields}{pi}{sup 0}{gamma}{gamma} is a check of the procedure. Scalar meson effects are seen to be irrelevant for {eta} Prime {yields}{pi}{sup 0}{gamma}{gamma}, while a significant scalar contribution due to the {sigma}(500) resonance seems to emerge in the case of {eta} Prime {yields}{pi}{sup 0}{gamma}{gamma}. Future measurements coming from KLOE-2, Crystal Ball, WASA, and BES-III will elucidate if any of these processes carry an important scalar contribution or they are simply driven by the exchange of vector mesons.

  17. Eta Meson Production in Proton-Proton and Nuclear Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Dick, Frank

    2008-01-01

    Total cross sections for eta meson production in proton - proton collisions are calculated. The eta meson is mainly produced via decay of the excited nucleon resonance at 1535 MeV. A scalar quantum field theory is used to calculate cross sections, which also include resonance decay. Comparison between theory and experiment is problematic near threshold when resonance decay is not included. When the decay is included, the comparison between theory and experiment is much better.

  18. Accelerated test methods for life prediction of hermetic motor insulation systems exposed to alternative refrigerant/lubricant mixtures. Final report

    SciTech Connect

    Ellis, P.F. II; Ferguson, A.F.

    1995-04-19

    In 1992, the Air-Conditioning and Refrigeration Technology Institute, Inc. (ARTI) contracted Radian Corporation to ascertain whether an improved accelerated test method or procedure could be developed that would allow prediction of the life of motor insulation materials used in hermetic motors for air-conditioning and refrigeration equipment operated with alternative refrigerant/lubricant mixtures. Phase 1 of the project, Conceptual Design of an accelerated test method and apparatus, was successfully completed in June 1993. The culmination of that effort was the concept of the Simulated Stator Unit (SSU) test. The objective of the Phase 2 limited proof-of-concept demonstration was to: answer specific engineering/design questions; design and construct an analog control sequencer and supporting apparatus; and conduct limited tests to determine the viability of the SSU test concept. This report reviews the SSU test concept, and describes the results through the conclusion of the proof-of-concept prototype tests in March 1995. The technical design issues inherent in transforming any conceptual design to working equipment have been resolved, and two test systems and controllers have been constructed. Pilot tests and three prototype tests have been completed, concluding the current phase of work. One prototype unit was tested without thermal stress loads. Twice daily insulation property measurements (IPMs) on this unit demonstrated that the insulation property measurements themselves did not degrade the SSU.

  19. Eta Carinae viewed from different vantages

    NASA Astrophysics Data System (ADS)

    Gull, T. R.

    2008-04-01

    The spatially-resolved winds of the massive binary, Eta Carinae, extend an arcsecond on the sky, well beyond the 10 to 20 milliarcsecond binary orbital dimension. Stellar wind line profiles, observed at very different angular resolutions of VLTI/AMBER, HST/STIS and VLT/UVES, provide spatial information on the extended wind interaction structure as it changes with orbital phase. These same wind lines, observable in the starlight scattered off the foreground lobe of the dusty Homunculus, provide time-variant line profiles viewed from significantly different angles. Comparisons of direct and scattered wind profiles observed in the same epoch and at different orbital phases provide insight on the extended wind structure and promise the potential for three-dimensional imaging of the outer wind structures. Massive, long-lasting clumps, including the nebularWeigelt blobs, originated during the two historical ejection events. Wind interactions with these clumps are quite noticeable in spatially-resolved spectroscopy. As the 2009.0 minimum approaches, analysis of existing spectra and 3-D modeling are providing bases for key observations to gain further understanding of this complex massive binary.

  20. Eta Carinae: Viewed from Multiple Vantage Points

    NASA Technical Reports Server (NTRS)

    Gull, Theodore

    2007-01-01

    The central source of Eta Carinae and its ejecta is a massive binary system buried within a massive interacting wind structure which envelops the two stars. However the hot, less massive companion blows a small cavity in the very massive primary wind, plus ionizes a portion of the massive wind just beyond the wind-wind boundary. We gain insight on this complex structure by examining the spatially-resolved Space Telescope Imaging Spectrograph (STIS) spectra of the central source (0.1") with the wind structure which extends out to nearly an arcsecond (2300AU) and the wind-blown boundaries, plus the ejecta of the Little Homunculus. Moreover, the spatially resolved Very Large Telescope/UltraViolet Echelle Spectrograph (VLT/UVES) stellar spectrum (one arcsecond) and spatially sampled spectra across the foreground lobe of the Homunculus provide us vantage points from different angles relative to line of sight. Examples of wind line profiles of Fe II, and the.highly excited [Fe III], [Ne III], [Ar III] and [S III)], plus other lines will be presented.

  1. Advanced Test Accelerator (ATA) injector

    SciTech Connect

    Jackson, C.H.; Bubp, D.G.; Fessenden, T.J.; Hester, R.E.; Neil, V.K.; Paul, A.C.; Prono, D.S.

    1983-03-09

    The ATA injector, developed from experience gained from the Experimental Test Accelerator (ETA) linac, has recently been completed. The injector consists of ten 0.25 MV cells that are used to develop 2.5 MV across a single diode gap. The 10 kA beam is extracted from a 500 cm/sup 2/ plasma cathode at average rates of up to 5 Hz and burst rates to 1 kHz. Pulsed power from 20 water filled blumleins is divided and introduced symmetrically through four ports on each cell. All major insulators are fabricated from filled epoxy castings. With these improvements, the ATA injector is smaller than the ETA injector; has a faster pulse response; has lower voltage stress on insulators and higher ultimate performance. Injector characterization tests began in October 1982. These tests include beam current, energy, and emittance measurements.

  2. Present Status And First Results of the Final Focus Beam Line at the KEK Accelerator Test Facility

    SciTech Connect

    Bambade, P.; Alabau Pons, M.; Amann, J.; Angal-Kalinin, D.; Apsimon, R.; Araki, S.; Aryshev, A.; Bai, S.; Bellomo, P.; Bett, D.; Blair, G.; Bolzon, B.; Boogert, S.; Boorman, G.; Burrows, P.N.; Christian, G.; Coe, P.; Constance, B.; Delahaye, Jean-Pierre; Deacon, L.; Elsen, E.; /DESY /Valencia U., IFIC /KEK, Tsukuba /Beijing, Inst. High Energy Phys. /Savoie U. /Fermilab /Ecole Polytechnique /KEK, Tsukuba /Kyungpook Natl. U. /KEK, Tsukuba /Pohang Accelerator Lab. /Kyoto U., Inst. Chem. Res. /Savoie U. /Daresbury /Tokyo U. /Royal Holloway, U. of London /Kyungpook Natl. U. /Pohang Accelerator Lab. /Tokyo U. /KEK, Tsukuba /SLAC /University Coll. London /KEK, Tsukuba /SLAC /Royal Holloway, U. of London /KEK, Tsukuba /Tokyo U. /SLAC /Tohoku U. /KEK, Tsukuba /Tokyo U. /Pohang Accelerator Lab. /Brookhaven /SLAC /Oxford U., JAI /SLAC /Orsay /KEK, Tsukuba /Oxford U., JAI /Orsay /Fermilab /Tohoku U. /Manchester U. /CERN /SLAC /Tokyo U. /KEK, Tsukuba /Oxford U., JAI /Hiroshima U. /KEK, Tsukuba /CERN /KEK, Tsukuba /Oxford U., JAI /Ecole Polytechnique /SLAC /Oxford U., JAI /Fermilab /SLAC /Liverpool U. /SLAC /Tokyo U. /SLAC /Tokyo U. /KEK, Tsukuba /SLAC /CERN

    2011-11-11

    ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described.

  3. Present status and first results of the final focus beam line at the KEK Accelerator Test Facility

    NASA Astrophysics Data System (ADS)

    Bambade, P.; Alabau Pons, M.; Amann, J.; Angal-Kalinin, D.; Apsimon, R.; Araki, S.; Aryshev, A.; Bai, S.; Bellomo, P.; Bett, D.; Blair, G.; Bolzon, B.; Boogert, S.; Boorman, G.; Burrows, P. N.; Christian, G.; Coe, P.; Constance, B.; Delahaye, J.-P.; Deacon, L.; Elsen, E.; Faus-Golfe, A.; Fukuda, M.; Gao, J.; Geffroy, N.; Gianfelice-Wendt, E.; Guler, H.; Hayano, H.; Heo, A.-Y.; Honda, Y.; Huang, J. Y.; Hwang, W. H.; Iwashita, Y.; Jeremie, A.; Jones, J.; Kamiya, Y.; Karataev, P.; Kim, E.-S.; Kim, H.-S.; Kim, S. H.; Komamiya, S.; Kubo, K.; Kume, T.; Kuroda, S.; Lam, B.; Lyapin, A.; Masuzawa, M.; McCormick, D.; Molloy, S.; Naito, T.; Nakamura, T.; Nelson, J.; Okamoto, D.; Okugi, T.; Oroku, M.; Park, Y. J.; Parker, B.; Paterson, E.; Perry, C.; Pivi, M.; Raubenheimer, T.; Renier, Y.; Resta-Lopez, J.; Rimbault, C.; Ross, M.; Sanuki, T.; Scarfe, A.; Schulte, D.; Seryi, A.; Spencer, C.; Suehara, T.; Sugahara, R.; Swinson, C.; Takahashi, T.; Tauchi, T.; Terunuma, N.; Tomas, R.; Urakawa, J.; Urner, D.; Verderi, M.; Wang, M.-H.; Warden, M.; Wendt, M.; White, G.; Wittmer, W.; Wolski, A.; Woodley, M.; Yamaguchi, Y.; Yamanaka, T.; Yan, Y.; Yoda, H.; Yokoya, K.; Zhou, F.; Zimmermann, F.

    2010-04-01

    ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described.

  4. High transverse momentum {eta} meson production in p+p,d+Au, and Au+Au collisions at {radical}(s{sub NN})=200 GeV

    SciTech Connect

    Adler, S. S.; Aronson, S. H.; Chujo, T.; David, G.; Desmond, E. J.; Drees, K. A.; Ewell, L.; Franz, A.; Guryn, W.; Haggerty, J. S.; Harvey, M.; Johnson, B. M.; Kistenev, E.; Kroon, P. J.; Makdisi, Y. I.; Mioduszewski, S.; Mitchell, J. T.; Morrison, D. P.; O'Brien, E.; Pinkenburg, C.

    2007-02-15

    Inclusive transverse momentum spectra of {eta} mesons in the range p{sub T}{approx_equal}2-12 GeV/c have been measured at midrapidity (|{eta}|<0.35) by the PHENIX experiment at RHIC in p+p,d+Au, and Au+Au collisions at {radical}(s{sub NN})=200 GeV. The {eta} mesons are reconstructed through their {eta}{yields}{gamma} {gamma} channel for the three colliding systems as well as through the {eta}{yields}{pi}{sup 0}{pi}{sup +}{pi}{sup -} decay mode in p+p and d+Au collisions. The nuclear modification factor in d+Au collisions, R{sub dAu}(p{sub T}){approx_equal}1.0-1.1, suggests at most only modest p{sub T} broadening (''Cronin enhancement''). In central Au+Au reactions, the {eta} yields are significantly suppressed, with R{sub AuAu}(p{sub T}){approx_equal}0.2. The ratio of {eta} to {pi}{sup 0} yields is approximately constant as a function of p{sub T} for the three colliding systems in agreement with the high-p{sub T} world average of R{sub {eta}/{pi}{sup 0}}{approx_equal}0.5 in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions for a wide range of center-of-mass energies ({radical}(s{sub NN}){approx_equal}3-1800 GeV) as well as, for high scaled momentum x{sub p}, in e{sup +}e{sup -} annihilations at {radical}(s)=91.2 GeV. These results are consistent with a scenario where high-p{sub T} {eta} production in nuclear collisions at the Relativistic Heavy Ion Collider is largely unaffected by initial-state effects but where light-quark mesons ({pi}{sup 0},{eta}) are equally suppressed due to final-state interactions of the parent partons in the dense medium produced in Au+Au reactions.

  5. Endothelin-1 critically contribute to EPC reduction and dysfunction via an ETA/NADPH oxidase pathway-induced oxidative stress in salt-sensitive hypertension

    PubMed Central

    Chen, Dan-Dan; Dong, Yu-Gang; Chen, Alex F.

    2012-01-01

    Circulating endothelial progenitor cells (EPCs) are reduced in hypertension, which inversely correlates with its mortality. DOCA–salt hypertension features elevated ET-1 and oxidative stress. We tested the hypothesis that ET-1 induces EPC dysfunction by elevating oxidative stress through the ETA/NADPH oxidase pathway in salt-sensitive hypertension. Both ETA and ETB receptors were expressed in EPCs, but only ETA receptors were significantly increased in EPCs of DOCA-salt rats. EPC number and function were reduced in DOCA-salt rats compared with Sham controls, both were reversed by in vivo blockade of ETA receptors or NADPH oxidase. The enzymatic activity of NAPDH oxidase and its subunits gp91phox, p22phox and Rac1 were augmented in EPCs of DOCA-salt rats, with concomitantly decreased antioxidant enzymes MnSOD, CuZnSOD, and GPx-1. ROS level was elevated in EPCs from DOCA-salt rats, accompanied by increased EPC telomerase inactivation, senescence and apoptosis, which were rescued by ETA or NADPH oxidase blockade. Cell therapy of normal or treated DOCA EPCs, but not untreated DOCA EPCs, significantly increased capillary density and blood perfusion in ischemic hindlimbs of DOCA-salt rats. p53 and Bax/Bcl-2 ratios were increased in EPCs of DOCA-salt rats, which were reversed by ETA antagonist or NADPH oxidase inhibitor or superoxide scavenger (PEG-SOD). Finally, in ETB-deficient rats, plasma ET-1 was elevated and EPC number and telomerase activity were diminished. These results demonstrate, for the first time, that ET-1 contributes to EPC reduction and dysfunction via an ETA/NADPH oxidase pathway-induced oxidative stress in salt-sensitive hypertension. PMID:22431579

  6. Final Environmental Assessment for the construction and operation of an office building at the Stanford Linear Accelerator Center. Part 2

    SciTech Connect

    1995-08-01

    The Department of Energy (DOE) has prepared an Environmental Assessment (EA), DOE/EA-1107, analyzing the environmental effects relating to the construction and operation of an office building at the Stanford Linear Accelerator Center (SLAC). SLAC is a national facility operated by Stanford University, California, under contract with DOE. The center is dedicated to research in elementary particle physics and in those fields that make use of its synchrotron facilities. The objective for the construction and operation of an office building is to provide adequate office space for existing SLAC Waste Management (WM) personnel, so as to centralize WM personnel and to make WM operations more efficient and effective. Based on the analyses in the EA, the DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 (NEPA). Therefore, the preparation of an Environmental Impact Statement is not required. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact (FONSI).

  7. Chaperonin containing T-complex polypeptide subunit eta (CCT-eta) is a specific regulator of fibroblast motility and contractility.

    PubMed

    Satish, Latha; Johnson, Sandra; Wang, James H-C; Post, J Christopher; Ehrlich, Garth D; Kathju, Sandeep

    2010-01-01

    Integumentary wounds in mammalian fetuses heal without scar; this scarless wound healing is intrinsic to fetal tissues and is notable for absence of the contraction seen in postnatal (adult) wounds. The precise molecular signals determining the scarless phenotype remain unclear. We have previously reported that the eta subunit of the chaperonin containing T-complex polypeptide (CCT-eta) is specifically reduced in healing fetal wounds in a rabbit model. In this study, we examine the role of CCT-eta in fibroblast motility and contractility, properties essential to wound healing and scar formation. We demonstrate that CCT-eta (but not CCT-beta) is underexpressed in fetal fibroblasts compared to adult fibroblasts. An in vitro wound healing assay demonstrated that adult fibroblasts showed increased cell migration in response to epidermal growth factor (EGF) and platelet derived growth factor (PDGF) stimulation, whereas fetal fibroblasts were unresponsive. Downregulation of CCT-eta in adult fibroblasts with short inhibitory RNA (siRNA) reduced cellular motility, both basal and growth factor-induced; in contrast, siRNA against CCT-beta had no such effect. Adult fibroblasts were more inherently contractile than fetal fibroblasts by cellular traction force microscopy; this contractility was increased by treatment with EGF and PDGF. CCT-eta siRNA inhibited the PDGF-induction of adult fibroblast contractility, whereas CCT-beta siRNA had no such effect. In each of these instances, the effect of downregulating CCT-eta was to modulate the behavior of adult fibroblasts so as to more closely approximate the characteristics of fetal fibroblasts. We next examined the effect of CCT-eta modulation on alpha-smooth muscle actin (alpha-SMA) expression, a gene product well known to play a critical role in adult wound healing. Fetal fibroblasts were found to constitutively express less alpha-SMA than adult cells. Reduction of CCT-eta with siRNA had minimal effect on cellular beta-actin but

  8. Searching for Radial Velocity Variations in eta Carinae

    NASA Technical Reports Server (NTRS)

    Iping, R. C.; Sonneborn, G.; Gull, T. R.; Ivarsson, S.; Nielsen, K.

    2006-01-01

    A hot companion of eta Carinae has been detected using high resolution spectra (905 - 1180 A) obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite (see poster by Sonneborn et al.). Analysis of the far-UV spectrum shows that eta Car B is a luminous hot star. The N II 1084-86 emission feature indicates that the star may be nitrogen rich. The FUV continuum and the S IV 1073 P-Cygni wind line suggest that the effective temperature of eta Car B is at least 25,000 K. FUV spectra of eta Carinae were obtained with the FUSE satellite at 9 epochs between 2000 February and 2005 July. The data consists of 12 observations taken with the LWRS aperture (30x30 arcsec), three with the HIRS aperture (1.25x20 arcsec), and one MRDS aperture (4x20 arcsec). In this paper we discuss the analysis of these spectra to search for radial velocity variations associated with the 5.54-year binary orbit of Eta Car AB.

  9. Tracing the wind interface of the massive binary Eta Carinae

    NASA Astrophysics Data System (ADS)

    Nielsen, Krister

    2007-07-01

    The binarity of Eta Carinae has been debated for a long time, but most recent evidence favors a binary star interpretation. However, very little is known about the nature of the companion star. Over Eta Carinae's spectroscopic period many observable wind lines in the NUV/Optical region, have been shown to exhibit peculiar line profiles with unusual velocity shifts relative to the system velocity. Some of the lines are exclusively blue-shifted over the entire 5.54 yr cycle and their ionization/excitation imply formation in the interface between the two massive stars. Especially, the He I emission lines are mainly formed in the wind interface region. Since the wind momentum is much larger for the primary star than its companion, the wind interface is located fairly close to the companion. Consequently, by tracing the He I emission we can construct a radial velocity curve that will describe the motion of the companion star and will derive the relation between the masses of the binary system stars. Furthermore, we will measure velocity and intensity variations in H I and Fe II to further investigate the ionization/excitation structure throughout Eta Carinae's wind. The analysis of the central source of Eta Carinae, due to the closeness of the two stars in the binary system {30 AU} and the intervening matter in line-of-sight towards Eta Carinae, is extremely dependent on data obtained with high angular resolving power. The HST archival data is crucial for the continuance of this project.

  10. Excited Ejecta in Light of Sight from Eta Car

    NASA Technical Reports Server (NTRS)

    Vieira, G.; Gull, T. R.; Danks, A.

    2003-01-01

    In the NUV spectrum of Eta Car, we have resolved many narrow absorption lines of neutral and singly-ionized elements with the Space Telescope Imaging Spectrograph. We report for the first time the detection of interstellar vanadium in absorption, and many highly-excited absorption lines of Fe, Cr, Ti, Ni, Co, Mn, and Mg. These elements, normally tied up in dust grains in the ISM, are located within wall of the Homunculus within 20,000 A.U. of Eta Car. Stellar radiation and stellar wind are interacting with the wall. Dust is likely being modified and/or destroyed. Previous Homunculus studies have demonstrated that nitrogen is overabundant and that carbon and oxygen emission lines are weak, or non-existent. Are the large column densities of these heavy elements due to abundance effects, excitation mechanisms, or modified grains? We may gain insight as Eta Car goes through its spectroscopic minimum in the summer of 2003.

  11. Is the Ejecta of ETA Carinae Overabundant or Overexcited

    NASA Technical Reports Server (NTRS)

    Gull, Theodore; Davidson, Kris; Johansson, Sveneric; Damineli, Augusto; Ishibashi, Kaxunori; Corcoran, Michael; Hartman, Henrick; Viera, Gladys; Nielsen, Krister

    2003-01-01

    The ejecta of Eta Carinae, revealed by HST/STIS, are in a large range of physical conditions. As Eta Carinae undergoes a 5.52 period, changes occur in nebular emission and nebular absorption. "Warm" neutral regions, partially ionized regions, and fully ionized regions undergo significant changes. Over 2000 emission lines, most of Fe-like elements, have been indentified in the Weigelt blobs B and D. Over 500 emission lines have been indentified in the Strontium Filament. An ionized Little Homunculus is nestled within the neutral-shelled Homunculus. In line of sight, over 500 nebular absorption lines have been identified with up to twenty velocity components. STIS is following changes in many nebular emission and absorption lines as Eta Carinae approaches the minimum, predicted to be in June/July 2003, during the General Assembly. Coordinated observations with HST, CHANDRA, RXTE, FUSE, UVES/VLT, Gemini and other observatories are following this minimum.

  12. 75 FR 53982 - Proposed Information Collection Request of the ETA 207, Nonmonetary Determination Activities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-02

    ... Determination Activities Report; Comment Request on Extension Without Change (OMB 1205-0150) AGENCY: Employment... . SUPPLEMENTARY INFORMATION: I. Background: The ETA 207 Report, Nonmonetary Determination Activities, contains... proposed extension collection of the ETA 207, Nonmonetary Determinations Activities Report. Comments...

  13. 76 FR 12760 - Comment Request for Information Collection for Report ETA 902, Disaster Unemployment Assistance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ..., Disaster Unemployment Assistance Activities (OMB Control No. 1205- 0051): Extension Without Change AGENCY... ETA 902, Disaster Unemployment Assistance Activities under the Robert T. Stafford Disaster Relief and.... Background The ETA 902 Report, Disaster Unemployment Assistance (DUA) Activities, is a monthly...

  14. The 2011 Eta-Aquariids observing campaign from La Palma

    NASA Astrophysics Data System (ADS)

    Bettonvil, Felix; Weiland, Thomas

    2013-01-01

    Because the Eta-Aquariids, the most prominent stream for Southern Hemisphere observers, are difficult to watch from mid-northern latitudes, a week-long visual observing campaign was carried out in May 2011 from La Palma, Canary Islands, Spain. There, on the grounds of the Observatorio del Roque de Los Muchachos (ORM), at an altitude of more than 2000 m above sea level, observing conditions were nearly perfect. As a consequence, we managed to record more than 300 Eta-Aquariids in about 30 hours of effective observing time. An impression of the campaign together with a summary of the results is given.

  15. Start of Eta Car's X-ray Minimum

    NASA Technical Reports Server (NTRS)

    Corcoran, Michael F.; Liburd, Jamar; Hamaguchi, Kenji; Gull, Theodore; Madura, Thomas; Teodoro, Mairan; Moffat, Anthony; Richardson, Noel; Russell, Chris; Pollock, Andrew; Owocki, Stan

    2014-01-01

    Analysis of Eta Car's X-ray spectrum in the 2-10 keV band using quicklook data from the XRay Telescope on Swift shows that the flux on July 30, 2014 was 4.9 plus or minus 2.0×10(exp-12) ergs s(exp-1)cm(exp-2). This flux is nearly equal to the X-ray minimum flux seen by RXTE in 2009, 2003.5, and 1998, and indicates that Eta Car has reached its X-ray minimum, as expected based on the 2024-day period derived from previous 2-10 keV observations with RXTE.

  16. 75 FR 3927 - Proposed Information Collection Request for the ETA 218, Benefit Rights and Experience Report...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... Information Collection Request for the ETA 218, Benefit Rights and Experience Report; Comment Request on... unemployment compensation programs. The data in the ETA 218, Benefit Rights and Experience Report, includes... extension for the collection of the ETA 218, Benefit Rights and Experience report. Comments are...

  17. Current status of E/f sub 1 (1420) and. iota. /. eta. (1450)

    SciTech Connect

    Chung, S.U. )

    1989-09-01

    The current status and future prospects are given of the E/f{sub 1} (1420) and the {eta}(1430) region containing the {iota}/{eta}(1450). These states are seen in the channels K{bar K}{pi} and {eta}{pi}{pi}. 43 refs., 10 figs., 5 tabs.

  18. Detection of the Compressed Primary Stellar Wind in eta Carinae

    NASA Technical Reports Server (NTRS)

    Teodoro, Mairan Macedo; Madura, Thomas I.; Gull, Theodore R.; Corcoran, Michael F.; Hamaguchi, K.

    2014-01-01

    A series of three HST/STIS spectroscopic mappings, spaced approximately one year apart, reveal three partial arcs in [Fe II] and [Ni II] emissions moving outward from eta Carinae. We identify these arcs with the shell-like structures, seen in the 3D hydrodynamical simulations, formed by compression of the primary wind by the secondary wind during periastron passages.

  19. Targeting Inaccurate Atomic Data in the Eta Car Ejecta Absorption

    NASA Technical Reports Server (NTRS)

    Nielsen, K. E.; Kober, G. Vieira; Gull, T. R.; Blackwell-Whitehead, R.; Nilsson, H.

    2006-01-01

    The input from the laboratory spectroscopist community has on many occasions helped the analysis of the eta Car spectrum. Our analysis has targeted spectra where improved wavelengths and oscillator strengths are needed. We will demonstrate how experimentally derived atomic data have improved our spectral analysis, and illuminate where more work still is needed.

  20. EMISSIONS PROCESSING FOR THE ETA/ CMAQ AIR QUALITY FORECAST SYSTEM

    EPA Science Inventory

    NOAA and EPA have created an Air Quality Forecast (AQF) system. This AQF system links an adaptation of the EPA's Community Multiscale Air Quality Model with the 12 kilometer ETA model running operationally at NOAA's National Center for Environmental Predication (NCEP). One of the...

  1. Eta Car's spectroscopic event begins to differ from 2009

    NASA Astrophysics Data System (ADS)

    Davidson, Kris; Mehner, Andrea; Humphreys, Roberta; Ishibash, K.; Martin, J. C.

    2014-08-01

    The middle of eta Car's 2014.6 spectroscopic event (periastron passage) occurred in mid-August (ATEL #6334, #6336, #6357, #6368, #6380). HST/STIS observations on July 13, July 30, and August 15 strongly suggest that the exotic He II 4687 emission is reappearing sooner than in the 2009.1 event.

  2. The Corrected Eta-Squared Coefficient: A Value Added Approach.

    ERIC Educational Resources Information Center

    Barnette, J. Jackson; McLean, James E.

    Eta-Squared (ES) is often used as a measure of strength of association of an effect, a measure often associated with effect size. It is also considered the proportion of total variance accounted for by an independent variable. It is simple to compute and interpret. However, it has one critical weakness cited by several authors (C. Huberty, 1994;…

  3. Spectra of Eta Carina from Objective Prism Photographic Plates

    NASA Astrophysics Data System (ADS)

    Cline, J. Donald; Castelaz, M.; Barker, T.

    2008-05-01

    Brightness and spectral variations of Eta Carina occur over a 5.5 year cycle. Emission lines were observed to fade in 1948, 1962, 1981, 1987, and 1992 (Damineli 1996, ApJ, 460, L49), and 1997 (Eta Carinae at the Millennium, ASP Conf. Ser. 179, ed. J.A. Morse, R.M. Humphreys, and A. Damineli). Gaps in the observation of spectra occur in 1970 and 1975 when two other such occurrences of the 5.5 year cycle were expected. Objective prism photographic plates of Eta Carina were found in the Astronomical Photographic Data Archive located at Pisgah Astronomical Research Institute. The plates belong to the University of Michigan survey (Houk 1978, Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars). One plate, IN emulsion + RG1 filter, was taken on 1968 July 4 UT. The other plate, IIaO emulsion, was taken on 1972 March 12 UT. These plates were taken between the 5.5 year cyclic events of 1970 and 1975 and therefore represent the usual emission line spectra. The spectrum of Eta Car was extracted from each of the objective prism plates and will be presented.

  4. Recent Results from HST/STIS Spectroscopy of eta Carinae

    NASA Astrophysics Data System (ADS)

    Davidson, K.; Gull, T. R.; Ishibashi, K.

    2001-06-01

    Repeated HST/STIS observations of eta Carinae and its ejecta have produced a large spectroscopic data set which is a unique resource for the astrophysics of massive stars, ejecta, and related topics. Here we report the existence of this data set and mention some implications concerning the star, spatially resolved from its bright diffuse ejecta.

  5. Eta Sigma Gamma: Preparing Leaders Today for Tomorrow's Challenges

    ERIC Educational Resources Information Center

    Brown, Kelli McCormack

    2007-01-01

    There is no one definition for a leader or for leadership, but most people can identify a leader and can provide qualities of a good leader or good leadership. The founders of Eta Gamma Gamma--William Bock, Warren Schaller, and Robert Synovitz--all displayed a critical characteristic of leadership by having and acting on a vision. Leadership has…

  6. The Eight-meter-wavelength Transient Array (ETA)

    NASA Astrophysics Data System (ADS)

    Simonetti, J. H.; Ellingson, S. W.; Patterson, C. D.; Taylor, W.; Venugopal, V.; Cutchin, S.; Boor, Z.

    2005-12-01

    The Eight-meter-wavelength Transient Array (ETA) is a radio telescope utilizing a low-cost backend, which implements flexible, reconfigurable computing techniques. It is designed to continuously monitor nearly the entire northern sky at 29-47MHz in a search for low-frequency radio transients (short pulses) from high-energy astrophysical phenomena. This antenna array, which is currently under construction, is located in a relatively radio-quiet area in the Blue Ridge Mountains southwest of Asheville, NC, at the Pisgah Astronomical Research Institute (PARI). The array consists of 12 dual-polarization dipole antennas. The core of the array is 10 antenna stations arranged in a 16-m diameter circle with one antenna station at the center. In addition, one antenna station is situated about 50m to the north of the core and another is about 50m to the east of the core. A 26-m dish on the PARI site (about 1km from the ETA core) will be used for follow-up, added aperture, longer baselines, and additional radio frequency interference (RFI) mitigation. Preliminary observations with one test antenna station have detected the expected Galactic emission in this frequency range; ETA will be Galactic-noise limited. The ETA backend will utilize off-the-shelf components and a cluster of Field Programmable Gate Arrays (FPGAs) for detecting pulses of various lengths, dispersion measures, and directions (synthesized delay beams), while incorporating various RFI countermeasures. Potential sources of radio transients that might be observed by ETA include gamma-ray bursts (prompt emission), supernovae (prompt emission), coalescing compact-object binaries (e.g., neutron star -- neutron star, neutron star -- black hole), and exploding primordial black holes. This array should detect giant pulses from the Crab Pulsar, and possibly other pulsars. ETA is a collaboration of the Electrical and Computer Engineering Department and Physics Department at Virginia Tech, and PARI. ETA work at Virginia

  7. Origin of the Central Constant Emission Component of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Hamaguchi, Kenji; Corocoran, M. F.; Gull, T.; Ishibashi, K.; Pittard, J. M.; Hillier, D. J.; Damineli, A.; Davidson, K.; Nielsen, K. E.; Owocki, S.; Henley, D.; Pollock, A.; Okazaki, A.

    2010-01-01

    The X-ray campaign observation of the wind-wind colliding (WWC) binary system, Eta Carinae, targeted at its periastron passage in 2003, presented a detailed view of the flux and spectral variations of the X-ray minimum phase. One of the discoveries in this campaign was a central constant emission (CCE) component very near the central WWC source (Hamaguchi et al. 2007, ApJ, 663, 522). The CCE component was noticed between 1-3 keY during the X-ray minima and showed no variation on either short timescales within any observation or long timescales of up to 10 years. Hamaguchi et al. (2007) discussed possible origins as collisionally heated shocks from the fast polar winds from Eta Car or the fast moving outflow from the WWC with the ambient gas, or shocked gas that is intrinsic to the wind of Eta Car. During the 2009 periastron passage, we launched another focussed observing campaign of Eta Carinae with the Chandra, XMM-Newton and Suzaku observatories, concentrating on the X-ray faintest phase named the deep X-ray minimum. Thanks to multiple observations during the deep X-ray minimum, we found that the CCE spectrum extended up to 10 keV, indicating presence of hot plasma of kT approx.4-6 keV. This result excludes two possible origins that assume relatively slow winds (v approx. 1000 km/s) and only leaves the possibility that the CCE plasma is wind blown bubble at the WWC downstream. The CCE spectrum in 2009 showed a factor of 2 higher soft band flux as the CCE spectrum in 2003, while the hard band flux was almost unchanged. This variation suggests decrease in absorption column along the line of sight. We compare this result with recent increase in V-band magnitude of Eta Carinae and discuss location of the CCE plasma.

  8. Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Sidorin, Anatoly

    2010-01-01

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  9. Linear Accelerators

    SciTech Connect

    Sidorin, Anatoly

    2010-01-05

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  10. Turbidity of a Binary Fluid Mixture: Determining Eta

    NASA Technical Reports Server (NTRS)

    Jacobs, Donald T.

    1996-01-01

    A ground based (1-g) experiment is in progress that will measure the turbidity of a density-matched, binary fluid mixture extremely close to its liquid-liquid critical point. By covering the range of reduced temperatures t equivalent to (T-T(sub c)) / T(sub c) from 10(exp -8) to 10(exp -2), the turbidity measurements will allow the critical exponent eta to be determined. No experiment has precisely determined a value of the critical exponent eta, yet its value is significant to theorists in critical phenomena. Relatively simple critical phenomena, as in the liquid-liquid system studied here, serve as model systems for more complex systems near a critical point.

  11. Turbidity of a binary fluid mixture: Determining eta

    NASA Technical Reports Server (NTRS)

    Jacobs, Donald T.

    1994-01-01

    A ground based (1-g) experiment is in progress that will measure the turbidity of a density-matched, binary fluid mixture extremely close to the critical point. By covering the range of reduced temperatures t is equivalent to (T-T(sub c))/T(sub c) from 10(exp -8) to 10(exp -2), the turbidity measurements will allow the critical exponent eta to be determined. No experiment has determined a value of the critical exponent eta, yet its value is significant to theorists in critical phenomena. Interpreting the turbidity correctly is important if future NASA flight experiments use turbidity as an indirect measurement of relative temperature in shuttle experiments on critical phenomena in fluids.

  12. A closer look at eta Carinae's surprising nitrogen chemistry

    NASA Astrophysics Data System (ADS)

    Cordiner, Martin; Jones, Paul; Millar, Tom; Charnley, Steven; Mcelroy, Daniel; Milam, Stefanie

    2013-04-01

    The ejecta of the luminous blue variable (LBV) star eta Carinae has recently been found to be surprisingly rich in simple nitrogen-bearing molecules, and theory predicts that more complex species such as HC3N and CH3CN are abundant in the warm inner regions of the Homunculus. We therefore propose to search for emission from HC3N, CH3CN and other nitrogen-bearing molecules in eta Carinae. We will also map HCN and HNC with unprecedented spatial detail to determine the origin and spatial extent of these species. The proposed observations will be crucial for developing chemical models of this source, which we will use to (1) promote understanding of the chemistry of this star and its mysterious ejecta and (2) provide information on molecule formation around massive stars that are about to undergo Type II supernova explosions.

  13. Mapping the interacting winds of Eta Carinae: Changes Across the Apastron

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Madura, T.; Corcoran, M. F.; Hamaguchi, K.; Teodoro, M.

    2014-01-01

    Since the May 2009 servicing mission to repair the Hubble Space Telescope, we have systematically mapped the central 1-2" region of Eta Carinae with the 0.1"-wide, long slit of the Space Telescope Imaging Spectrograph. Six mappings of selected forbidden emission lines began in the late recovery after the 2009.1 periastron event and now extend to phase 0.85 of Eta Carina's 5.54 year period. In addition to the recovery of the high state as depicted by [Fe III] (IP=16.6 eV) strictures and the stabilization of [Fe II] (IP=7.8 eV) features, we see components of at least three wind-blown shells that expand outward at 400 to 500 km/s. Virtually all forbidden emission originates from primary wind structures. The [Fe II] shells, moving at 470 km/s, are primary wind (420 km/s) structures slightly accelerated by the fast secondary wind (Teodoro et al, 2013 ApJ 773, L16T). The [Fe III] arcs, directly photo-ionized by the secondary star, also shift outward with time. Structures in both emissions shift in a general clockwork direction consistent with the derived orbital motion by Gull et al (2009 MNRAS 396, 1308) and revised by Madura et al (2012 MNRAS 420, 2064). With the continued development of the 3D hydrodynamic models we are able to compare the changing structures and determine limits to changes in the mass loss rate over this period of time. Additional mappings, to be obtained by seven additional HST visits, are scheduled at selected orbital phases to follow major changes in ionization structue due to the drop of high ionization to low ionization across the 2014.5 periastron passage. This work is funded by NASA grants to support HST research.

  14. Violent Encounters During The Great Eruption Of Eta Carinae And Other Luminous Transients

    NASA Astrophysics Data System (ADS)

    Smith, Nathan; Frew, David

    2011-01-01

    We present newly uncovered historical data containing over 50 observations of the brightness of Eta Carinae during the peak of its 19th century Great Eruption, which correct some mistakes in previously published lightcurves and paint a substantially different picture of the eruption. We compare the timing of brightening events to expected times of periastron encounters in the eccentric binary system, and we evaluate the extent to which such interactions may account for the observed variability. Periaston encounters may explain some aspects of the light curve, but new questions arise as well, and we discuss a possible physical model for the eruption. Finally, we mention potentially far-reaching implications for so-called "Supernova Impostors" and other luminous transients seen in other galaxies, which will be discovered in increasing numbers in upcoming transient searches like LSST.

  15. DETECTION OF THE COMPRESSED PRIMARY STELLAR WIND IN {eta} CARINAE

    SciTech Connect

    Teodoro, M.; Madura, T. I.; Gull, T. R.; Corcoran, M. F.; Hamaguchi, K.

    2013-08-10

    A series of three Hubble Space Telescope/Space Telescope Imaging Spectrograph spectroscopic mappings, spaced approximately one year apart, reveal three partial arcs in [Fe II] and [Ni II] emissions moving outward from {eta} Carinae. We identify these arcs with the shell-like structures, seen in the three-dimensional hydrodynamical simulations, formed by compression of the primary wind by the secondary wind during periastron passages.

  16. The eta Carinae Treasury Project and the HST/STIS

    NASA Technical Reports Server (NTRS)

    Martin, John C.; Davidson, Kris

    2006-01-01

    The HST Eta Carinae Treasury Project made extensive use of the HST/STIS from 1998 to the time of its failure in 2004. As one of the most prolific users of that instrument, the Treasury Project used the cross-dispersed spatial resolution of the STIS as few projects did. We present several enhancements to the existing STIS data reduction methods that are applicable to non-Treasury Project data in the STIS archive.

  17. Chandra X-Ray Observatory Image of Eta Carinae

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This Chandra X-Ray Observatory image of the mysterious superstar Eta Carinae reveals a surprising hot irner core, creating more questions than answers for astronomers. The image shows three distinct structures: An outer, horseshoe shaped ring about 2 light-years in diameter, a hot inner core about 3 light-months in diameter, and a hot central source less than a light-month in diameter which may contain the superstar. In 1 month, light travels a distance of approximately 489 billion miles (about 788 billion kilometers). All three structures are thought to represent shock waves produced by matter rushing away from the superstar at supersonic speeds. The temperature of the shock-heated gas ranges from 60 million degrees Kelvin in the central regions to 7 million degrees Kelvin on the outer structure. Eta Carinae is one of the most enigmatic and intriguing objects in our galaxy. Between 1837 and 1856, it increased dramatically in brightness to become the most prominent star in the sky except for Sirius, even through it is 7,500 light-years away, more than 80 times the distance to Sirius. This 'Great Eruption,' as it is called, had an energy comparable to a supernova, yet did not destroy the star, which faded to become a dim star, invisible to the naked eye. Since 1940, Eta Carinae has begun to brighten again, becoming visible to the naked eye. Photo credit: NASA/CXC/SAO

  18. High Velocity Absorption during Eta Car B's Periastron Passage

    NASA Technical Reports Server (NTRS)

    Nielsen, Krister E.; Groh, J. H.; Hillier, J.; Gull, Theodore R.; Owocki, S. P.; Okazaki, A. T.; Damineli, A.; Teodoro, M.; Weigelt, G.; Hartman, H.

    2010-01-01

    Eta Car is one of the most luminous massive stars in the Galaxy, with repeated eruptions with a 5.5 year periodicity. These events are caused by the periastron passage of a massive companion in an eccentric orbit. We report the VLT/CRIRES detection of a strong high-velocity, (<1900 km/s) , broad absorption wing in He I at 10833 A during the 2009.0 periastron passage. Previous observations during the 2003.5 event have shown evidence of such high-velocity absorption in the He I 10833 transition, allowing us to conclude that the high-velocity gas is crossing the line-of-sight toward Eta Car over a time period of approximately 2 months. Our analysis of HST/STlS archival data with observations of high velocity absorption in the ultraviolet Si IV and C IV resonance lines, confirm the presence of a high-velocity material during the spectroscopic low state. The observations provide direct detection of high-velocity material flowing from the wind-wind collision zone around the binary system, and we discuss the implications of the presence of high-velocity gas in Eta Car during periastron

  19. Fresh Clues in Eta Carinae's 2009.0 Event

    NASA Astrophysics Data System (ADS)

    Davidson, Kris; Martin, J. C.; Humphreys, R. M.; Mehner, A.; Ishibashi, K.; Ferland, G.; Hamann, F.

    2009-05-01

    Eta Carinae's most recent spectroscopic event climaxed in January 2009 and revealed significant new information. We obtained UV images with the HST/WFPC2, and violet-to-red spectroscopy with GMOS on the Gemini South telescope. The new NICI instrument on Gemini South obtained a remarkable set of near-IR images shortly after the peak of the event. Improved temporal coverage proves to be critical. With both HST/WFPC2 and Gemini/GMOS, the time intervals between observations were substantially smaller than we had achieved with HST/STIS and HST/ACS during the preceding event in mid-2003. Thus we find, for example, that the UV brightness of the central wind changed much faster than previous data could show or even hint. Meanwhile the behavior of the strange He II 4686 emission is greatly clarified, and a number of other features differed from the 2003 event. Regarding pre-event developments, Gemini/GMOS spectroscopy in 2007--2008 can be used to derive fresh constraints on the orbit of eta Car's hypothetical hot companion star. The high-spatial-resolution near-IR images obtained with Gemini/NICI show a dramatic new view of eta Car's Homunculus ejecta-nebula. Because of lesser extinction, these show deeper structure than the familiar HST images; some of the most conspicuous large near-IR structures have no UV-to-red counterparts. This program is partially funded by grants from STScI.

  20. Future directions in searching for eta-mesic nuclei

    NASA Astrophysics Data System (ADS)

    Haider, Quamrul; Liu, Lon-Chang

    2016-03-01

    Future directions in searching for eta-mesic nuclei: Q. Haider, Department of Physics and Engineering Physics, Fordham University, Bronx, N.Y. 10458, U.S.A. and L.C. Liu, Theoretical Division, Los Alamos National Laboratory, Los Alamos, N.M 87545, U.S.A. Eta-mesic nucleus or the quasibound nuclear state of an eta (η) meson in a nucleus is caused by strong-interaction force alone. This new type of nuclear species, which extends the landscape of nuclear physics, has been extensively studied since its prediction in 1986. In experimental search for η-mesic nucleus, transfer reactions have been frequently employed. One such reaction has led to the observation of the η-mesic nucleus 25Mg η . However, searching quasibound η-nucleus states in lighter nuclei such as 3He, 4He, and 11B has not yet yielded positive results. Searching η-mesic nuclei in medium-mass nuclear systems other than 25Mg is highly valuable. In view of the aforementioned experimental results, we suggest searching for more η-mesic nuclei in target nuclei having a mass number A >= 12 . Bronx, N.Y. 10458.

  1. 2{eta} or not 2{eta}? Insights into the Cu CVD process using a Cu(I) precursor

    SciTech Connect

    Kumar, R.; Maverick, A.W.; Fronczek, F.R.; Kim, A.J.; Butler, L.G.

    1993-12-31

    One of the first successful Cu(I) CVD precursors is (hfac)Cu{sup I}(COD), and this species continues to served as a model system. In the CVD process, a significant step is dissociation of the COD ligand. The energetics of this process have been estimated previously. However, it now appears that, in the solid state, (hfac)Cu{sup I}(COD) undergoes an exchange process that allows additional insight into the potential energy surface governing the Cu-COD interaction. The solid-state structure of (hfac)Cu{sup I}(COD) has been difficult to establish, but a combination of variable temperature X-ray and solid-state {sup 13}C NMR studies leads to the following picture. Cu{sup I} is three-coordinate, bound to the hfac ligand and bound preferentially to one olefin of the COD ligand. There is a small energy barrier associated with motion of the Cu into position for {eta}{sup 2}-binding to the other olefin; the COD and hfac ligands remain approximately stationary. Thus, there are two sites for Cu, now labeled {eta}{sup 2} and {eta}{sup 2}. This new interpretation of the solid-state structure differs from that of our 300 K data set and a previous report. In addition, the exchange process is intimately connected with the Cu-COD dissociation step in the CVD process.

  2. Can Accelerators Accelerate Learning?

    NASA Astrophysics Data System (ADS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-03-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ) [1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  3. PARTICLE ACCELERATOR

    DOEpatents

    Teng, L.C.

    1960-01-19

    ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

  4. Rare decay {eta}{r_arrow}{pi}{pi}{gamma}{gamma} in chiral perturbation theory

    SciTech Connect

    Knoechlein, G.; Scherer, S.; Drechsel, D.

    1996-04-01

    We investigate the rare radiative {eta} decay modes {eta}{r_arrow}{pi}{sup +}{pi}{sup {minus}}{gamma}{gamma} and {eta}{r_arrow}{pi}{sup 0}{pi}{sup 0}{gamma}{gamma} within the framework of chiral perturbation theory at {ital O}({ital p}{sup 4}). We present photon spectra and partial decay rates for both processes as well as a Dalitz contour plot for the charged decay. {copyright} {ital 1996 The American Physical Society.}

  5. Branching Fraction Measurements of the Color-Suppressed Decays B0bar to D(*)0 pi0, D(*)0 eta, D(*)0 omega, and D(*)0 eta_prime and Measurement of the Polarization in the Decay B0bar to D*0 omega

    SciTech Connect

    Lees, J.P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Milanes, D.A.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Koch, H.; Schroeder, T.; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U. /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2012-02-14

    We report updated branching fraction measurements of the color-suppressed decays {bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}, D*{sup 0}{pi}{sup 0}, D{sup 0}{eta}, D*{sup 0}{eta}, D{sup 0}{omega}, D*{sup 0}{omega}, D{sup 0}{eta}', and D*{sup 0}{eta}'. We measure the branching fractions (x10{sup -4}): {Beta}({bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}) = 2.69 {+-} 0.09 {+-} 0.13, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{pi}{sup 0}) = 3.05 {+-} 0.14 {+-} 0.28, {Beta}({bar B}{sup 0} {yields} D{sup 0}{eta}) = 2.53 {+-} 0.09 {+-} 0.11, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{eta}) = 2.69 {+-} 0.14 {+-} 0.23, {Beta}({bar B}{sup 0} {yields} D{sup 0}{omega}) = 2.57 {+-} 0.11 {+-} 0.14, {Beta}({bar B}{sup 0} {yields} D*{sup 0}{omega}) = 4.55 {+-} 0.24 {+-} 0.39, {Beta}({bar B}{sup 0} {yields} D{sup 0}{eta}') = 1.48 {+-} 0.13 {+-} 0.07, and {Beta}({bar B}{sup 0} {yields} D*{sup 0}{eta}') = 1.49 {+-} 0.22 {+-} 0.15. We also present the first measurement of the longitudinal polarization fraction of the decay channel D*{sup 0}{omega}, f{sub L} = (66.5 {+-} 4.7 {+-} 1.5)%. In the above, the first uncertainty is statistical and the second is systematic. The results are based on a sample of (454 {+-} 5) x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance, with the BABAR detector at the PEP-II storage rings at SLAC. The measurements are the most precise determinations of these quantities from a single experiment. They are compared to theoretical predictions obtained by factorization, Soft Collinear Effective Theory (SCET) and perturbative QCD (pQCD). We find that the presence of final state interactions is favored and the measurements are in better agreement with SCET than with pQCD.

  6. The adaptive CCCG({eta}) method for efficient solution of time dependent partial differential equations

    SciTech Connect

    Campos, F.F.; Birkett, N.R.C.

    1996-12-31

    The Controlled Cholesky factorisation has been shown to be a robust preconditioner for the Conjugate Gradient method. In this scheme the amount of fill-in is defined in terms of a parameter {eta}, the number of extra elements allowed per column. It is demonstrated how an optimum value of {eta} can be automatically determined when solving time dependent p.d.e.`s using an implicit time step method. A comparison between CCCG({eta}) and the standard ICCG solving parabolic problems on general grids shows CCCG({eta}) to be an efficient general purpose solver.

  7. Measurements of the mass and width of the eta(c) meson and of an eta(c)(2S) candidate.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Robbe, P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kral, J F; Kukartsev, G; LeClerc, C; Levi, M E; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Romosan, A; Ronan, M T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Knowles, D J; Morgan, S E; Penny, R C; Watson, A T; Watson, N K; Deppermann, T; Goetzen, K; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schmuecker, H; Steinke, M; Barlow, N R; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Mackay, C; Wilson, F F; Abe, K; Cuhadar-Donszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; McKemey, A K; Blinov, V E; Bukin, A D; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Shen, B C; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Schwanke, U; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Kuznetsova, N; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Beringer, J; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Turri, M; Walkowiak, W; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Roy, J; Smith, J G; Van Hoek, W C; Zhang, L; Harton, J L; Hu, T; Soffer, A; Toki, W H; Wilson, R J; Zhang, J; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Dubitzky, R S; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Schubert, J; Schubert, K R; Schwierz, R; Spaan, B; Wilden, L; Bernard, D; Bonneaud, G R; Brochard, F; Cohen-Tanugi, J; Grenier, P; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Khan, A; Lavin, D; Muheim, F; Playfer, S; Swain, J E; Tinslay, J; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Anulli, F; Baldini-Ferroli, R; Biasini, M; Calcaterra, A; De Sangro, R; Falciai, D; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Pioppi, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Morii, M; Won, E; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Eschrich, I; Gaillard, J R; Morton, G W; Nash, J A; Sanders, P; Taylor, G P; Grenier, G J; Lee, S-J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Brigljević, V; Cheng, C H; Lange, D J; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, E; Gamet, R; Kay, M; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Harrison, P F; Shorthouse, H W; Strother, P; Vidal, P B; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; George, S; Green, M G; Kurup, A; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, R J; Forti, A C; Hart, P A; Jackson, F; Lafferty, G D; Lyon, A J; Weatherall, J H; Williams, J C; Farbin, A; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Milek, M; Patel, P M; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Cote-Ahern, D; Hast, C; Taras, P; Nicholson, H; Cartaro, C; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; LoSecco, J M; Gabriel, T A; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Wong, Q K; Brau, J; Frey, R; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; John, M J J; Leruste, Ph; Ocariz, J; Pivk, M; Roos, L; Stark, J; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lu, C; Miftakov, V; Olsen, J; Smith, A J S; Tanaka, H A; Varnes, E W; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Olaiya, E O; Xella, S M; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yeche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Convery, M R; Coupal, D P; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Grauges-Pous, E; Hadig, T; Halyo, V; Hryn'ova, T; Innes, W R; Jessop, C P; Kelsey, M H; Kim, P; Kocian, M L; Langenegger, U; Leith, D W G S; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Robertson, S H; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wright, D H; Young, C C; Burchat, P R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Johnson, J R; Kutter, P E; Li, H; Liu, R; Di Lodovico, F; Mihalyi, A; Mohapatra, A K; Pan, Y; Prepost, R; Sekula, S J; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Neal, H

    2004-04-01

    The mass m(eta(c)) and total width Gamma(eta(c))(tot) of the eta(c) meson have been measured in two-photon interactions at the SLAC e(+)e(-) asymmetric B Factory with the BABAR detector. With a sample of approximately 2500 reconstructed eta(c)-->K(0)(S)K+/-pi(-/+) decays in 88 fb(-1) of data, the results are m(eta(c))=2982.5+/-1.1(stat)+/-0.9(syst) MeV/c(2) and Gamma(eta(c))(tot)=34.3+/-2.3(stat)+/-0.9(syst) MeV/c(2). Using the same decay mode, a second resonance with 112+/-24 events is observed with a mass of 3630.8+/-3.4(stat)+/-1.0(syst) MeV/c(2) and width of 17.0+/-8.3(stat)+/-2.5(syst) MeV/c(2). This observation is consistent with expectations for the eta(c)(2S) state. PMID:15089530

  8. New measurement of exclusive decays of the {chi}{sub c0} and {chi}{sub c2} to two-meson final states

    SciTech Connect

    Asner, D. M.; Edwards, K. W.; Reed, J.; Robichaud, A. N.; Tatishvili, G.; Briere, R. A.; Vogel, H.; Onyisi, P. U. E.; Rosner, J. L.; Alexander, J. P.; Cassel, D. G.; Duboscq, J. E.; Ehrlich, R.; Fields, L.; Galik, R. S.; Gibbons, L.; Gray, R.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.

    2009-04-01

    Using a sample of 2.59x10{sup 7} {psi}(2S) decays collected by the CLEO-c detector, we present results of a study of {chi}{sub c0} and {chi}{sub c2} decays into two-meson final states. We present the world's most precise measurements of the {chi}{sub cJ,(J=0,2)}{yields}{pi}{sup +}{pi}{sup -}, {pi}{sup 0}{pi}{sup 0}, K{sup +}K{sup -}, K{sub S}{sup 0}K{sub S}{sup 0}, {eta}{eta}, and {eta}{sup '}{eta}{sup '} branching fractions, and a search for {chi}{sub c} decays into {eta}{eta}{sup '}. These results shed light on the mechanism of charmonium decays into pseudoscalar mesons.

  9. Eta Carinae, the Integral Nebula and the Homunculus Observations

    NASA Astrophysics Data System (ADS)

    Gull, Theodore

    2000-07-01

    In the past two years, observations of Eta Carina have revealed much new and very exciting information. Augusto Damineli noted a 5.5 year period in the visible and near infrared spectroscopy. Michael Corcoran and Bish Ishibashi noticed modulation of the x-ray fluxes with various periodicities around 90 days before and after the xray and radio minimum in December 1997. Observations, done in March 1998 under proposal 7302 {Davidson et al} from 1640A to 10400A using STIS in GXXXM mode and the 50x0.1 arcsecond slit, revealed much new information in the immediate regions of Eta Carina. The slit orientation was slightly off the major axis of the Homunculus, but passed through Weigelt components B and D. Bish Ishibashi and Ted Gull have reduced the data and provided it to various team members. Torgil Zethson has identified well over 90 percent of the emission lines in the March 1998 spectrum and finds most to be FeII emission lines. Based upon the past ground-based history of Eta Carina, we expected that FeIII and other high ionization states would return within the year. STIS GTO observations {Ted Gull, PI program 8036} characterized a bright internal emission nebula by turning the slit 90 degrees for visit 1 and studying the changes in spectrum as the FeIII lines appear by using visit 2 with the identical slit orientation from March 19, 1998. Data from the four visits of STIS to Eta Carinae between December 1997 and February 1999 demonstrate that the star has brightened by a factor of two during that interval and that the immediate nebulosity has tripled in surface brightness. Moreover a small circular nebular shell, seen in multiple [Fe II] lines has disappeared and the opacity in the 2000 to 3000A region obscuring the star has lifted considerable as the Fe II is converting to Fe III. Given the strong changes in the spectrum, we have chosen to use the six orbits in two visits. Visit 1 will be a precise repeat of the March 1998 and February 1999 observations, adjusted

  10. Endothelin ETA receptor expression in human cerebrovascular smooth muscle cells.

    PubMed Central

    Yu, J. C.; Pickard, J. D.; Davenport, A. P.

    1995-01-01

    1. Endothelin (ET) has been implicated in cerebrovasospasm for example, following subarachnoid haemorrhage, and blocking the interaction of ET with its receptors on cerebral vessels, may be of therapeutic benefit. The aim of our study was to characterize endothelin receptor sub-types on medial smooth muscle cells of human cerebral vessels. Cultures of vascular smooth muscle cells were explanted from human cerebral resistance vessels and characterized as human brain smooth muscle cells (HBSMCs). 2. Over a 48 h incubation period, HBSMC cultures secreted comparable levels of immunoreactive (IR) big endothelin-1 (big ET-1) and IR endothelin (ET): 12.7 +/- 10.3 and 8.3 +/- 5.6 pmol/10(6) cells, respectively (mean +/- s.e. mean from three different individuals), into the culture medium. 3. Total RNA was extracted from cultures of human brain smooth muscle cells. Reverse-transcriptase polymerase chain reaction (RI-PCR) assays and subsequent product separation by agarose gel electrophoresis revealed single bands corresponding to the expected product sizes encoding cDNA for ETA (299 base pairs) and ETB (428 base pairs) (n = 3 different cultures). 4. Autoradiography demonstrated the presence of specific binding sites for [125I]-ET-1 which labels all ET receptors, and [125I]-PD151242, an ETA subtype-selective antagonist which exclusively labels ETA receptors, but no specific-binding was detected using ETB subtype-selective [125I]-BQ3020 (n = 3 different cultures, in duplicate). 5. In saturation binding assays, [123I]-ET-1 bound with high affinity: KD = 0.8 +/- 0.1 nM and Bmax = 690 +/- 108 fmol mg-1. A one-site fit was preferred and Hill slopes were close to unity over the concentration range (10(-12) to 10(-8) M). [125I]-PD151242 also bound with similar affinity: KD = 0.4 +/- 0.1 nM and Bmax = 388 +/- 68 fmol mg-1 (mean +/- s.e. mean, n = 3 different cultures). Again, a one-site fit was preferred and Hill slopes were close to unity over the concentration range. Unlabelled PD

  11. The {eta}(2225) observed by the BES Collaboration

    SciTech Connect

    Li Demin; Ma Bing

    2008-05-01

    In the framework of the {sup 3}P{sub 0} meson decay model, the strong decays of the 3{sup 1}S{sub 0} and 4{sup 1}S{sub 0} ss states are investigated. It is found that in the presence of the initial state mass being 2.24 GeV, the total widths of the 3{sup 1}S{sub 0} and 4{sup 1}S{sub 0} ss states are about 438 MeV and 125 MeV, respectively. Also, when the initial state mass varies from 2220 to 2400 MeV, the total width of the 4{sup 1}S{sub 0} ss state varies from about 100 to 132 MeV, while the total width of the 3{sup 1}S{sub 0} ss state varies from about 400 to 594 MeV. A comparison of the predicted widths and the experimental result of (0.19{+-}0.03{sub -0.06}{sup +0.04}) GeV, the width of the {eta}(2225) with a mass of (2.24{sub -0.02-0.02}{sup +0.03+0.03}) GeV recently observed by the BES Collaboration in the radiative decay J/{psi}{yields}{gamma}{phi}{phi}{yields}{gamma}K{sup +}K{sup -}K{sub S}{sup 0}K{sub L}{sup 0}, suggests that it would be very difficult to identify the {eta}(2225) as the 3{sup 1}S{sub 0} ss state, and the {eta}(2225) seams a good candidate for the 4{sup 1}S{sub 0} ss state.

  12. UV nebular absorption in Eta Car and Weigelt D

    NASA Astrophysics Data System (ADS)

    Nielsen, K. E.; Vieira, G. L.; Gull, T. R.; Lindler, D. J.; Eta Car HST Treasury Team

    2003-12-01

    The high angular and high spectral resolution of the HST/STIS MAMA echelle mode, provide an unique means to distinguish the physical structures surrounding Eta Car. Observations are parts of the HST treasury program (K. Davidson P.I.) for monitoring variations over Eta Car's spectroscopic minimum. Nebular emission is present above and below the stellar spectrum which is about 0.03'' wide. We have extracted the nebular part of the central source spectrum and compared it with the spectrum of Weigelt D, located approximately 0.2'' Northwest of the central source. The spectra show significant similarities and our conclusions are two-fold. First, the radiation from the Wiegelt blobs give an unwanted contribution to the spectrum of the central source, which emphasizes the importance of using an extracted spectrum in a spectral analysis. Second, the Weigelt blobs have so far been assumed to produce a pure emission line spectrum. However, this comparison shows the presence of similar absorption structures previously observed in the spectrum of the central star (Gull et al., 2003, submitted ApJL). Two velocity structures at approximately -50 and -500 km/s, respectively, have been observed in the Weigelt D spectrum. We present identifications of the absorption structures to supplement the emission line work performed by T. Zethson (2000, PhD Thesis) and provide additional information regarding the geometry of the inner parts of the Eta Car nebula. The -50 km/s velocity component is similar to the absorption structure at -146 km/s observed in the spectrum of the central object. If these velocity systems are related, this implies that the absorption component is located close to the central parts of the nebular system.

  13. Nebular Hydrogen Absorption in the Ejecta of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Ishibashi, K.; Davidson, K.; Fisher, Richard R. (Technical Monitor)

    2000-01-01

    Space Telescope Imaging Spectrograph (STIS) observations of Eta Carinae and immediate ejecta reveal narrow Balmer absorption lines in addition to the nebular-scattered broad P-Cygni absorptions. The narrow absorption correlates with apparent disk structure that separates the two Homunculus lobes. We trace these features about half way up the Northern lobe until the scattered stellar Balmer line doppler-shifts redward beyond the nebular absorption feature. Three-dimensional data cubes, made by mapping the Homunculus at Balmer alpha and Balmer beta with the 52 x 0.1 arcsecond aperture and about 5000 spectral resolving power, demonstrate that the absorption feature changes slowly in velocity with nebular position. We have monitored the stellar Balmer alpha line profile of the central source over the past four years. The equivalent width of the nebular absorption feature changes considerably between observations. The changes do not correlate with measured brightness of Eta Carinae. Likely clumps of neutral hydrogen with a scale size comparable to the stellar disk diameter are passing through the intervening light path on the timescales less than several months. The excitation mechanism involves Lyman alpha radiation (possibly the Lyman series plus Lyman continuum) and collisions leading to populating the 2S metastable state. Before the electron can jump to the ground state by two photon emission (lifetime about 1/8 second), a stellar Balmer photon is absorbed and the electron shifts to an NP level. We see the absorption feature in higher Balmer lines, and but not in Paschen lines. Indeed we see narrow nebular Paschen emission lines. At present, we do not completely understand the details of the absorption. Better understanding should lead to improved insight of the unique conditions around Eta Carinae that leads to these absorptions.

  14. [Sr II] Detected in a Nebular Filament Near Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, T.R.; Fisher, Richard (Technical Monitor)

    2000-01-01

    Observations with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope reveal a peculiar emission line region in the close vicinity to Eta Carinae. The lines of [SrII], [MnII], [CoII], [TiII], [NiII] and [FeI] are detected in the 6400-7000 Angstrom spectral interval at a blue-shifted velocity of approximately 95 km/sec and seem to be associated with a long, narrow filament with dimensions of less than 0.5 inches by 1.1 inches. The filament is notable as it is separate both in velocity and structure from the bright emission of the Integral Nebula. This filament is buried within the Homunculus and is not visible in direct images which are dominated by reflection nebulosities. In our literature searches we have found no evidence of strontium emission lines in nebulae. We are aware of permitted transitions of strontium seen in AGB stars. S-processed elements like strontium are not expected in the ejecta of a massive star like Eta Carinae. Detection of [SrII] and the fact that the [NiII], [MnII] and [CoII] lines are unusually strong compared to [FeI] are quite a surprise. It has long been known that nitrogen is overabundant in the ejecta of Eta Carinae. Is this processed material from the present star(s)? Has there been processed material ejected from a more evolved companion? The situation is decidedly mysterious. This research has been supported by NASA through STScI grants and the STIS GTO funding.

  15. Implementation of an Eta Belt Domain on Parallel Systems

    NASA Technical Reports Server (NTRS)

    Kouatchou, Jules; Rancic, Miodrag; Norris, Peter; Geiger, Jim

    2001-01-01

    We extend the Eta weather model from a regional domain into a belt domain that does not require meridional boundary conditions. We describe how the extension is achieved and the parallel implementation of the code on the Cray T3E and the SGI Origin 2000. We validate the forecast results on the two platforms and examine how the removal of the meridional boundary conditions affects these forecasts. In addition, using several domains of different sizes and resolutions, we present the scaling performance of the code on both systems.

  16. Eta Carinae in the Context of the Most Massive Stars

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Damineli, Augusto

    2009-01-01

    Eta Car, with its historical outbursts, visible ejecta and massive, variable winds, continues to challenge both observers and modelers. In just the past five years over 100 papers have been published on this fascinating object. We now know it to be a massive binary system with a 5.54-year period. In January 2009, Car underwent one of its periodic low-states, associated with periastron passage of the two massive stars. This event was monitored by an intensive multi-wavelength campaign ranging from -rays to radio. A large amount of data was collected to test a number of evolving models including 3-D models of the massive interacting winds. August 2009 was an excellent time for observers and theorists to come together and review the accumulated studies, as have occurred in four meetings since 1998 devoted to Eta Car. Indeed, Car behaved both predictably and unpredictably during this most recent periastron, spurring timely discussions. Coincidently, WR140 also passed through periastron in early 2009. It, too, is a intensively studied massive interacting binary. Comparison of its properties, as well as the properties of other massive stars, with those of Eta Car is very instructive. These well-known examples of evolved massive binary systems provide many clues as to the fate of the most massive stars. What are the effects of the interacting winds, of individual stellar rotation, and of the circumstellar material on what we see as hypernovae/supernovae? We hope to learn. Topics discussed in this 1.5 day Joint Discussion were: Car: the 2009.0 event: Monitoring campaigns in X-rays, optical, radio, interferometry WR140 and HD5980: similarities and differences to Car LBVs and Eta Carinae: What is the relationship? Massive binary systems, wind interactions and 3-D modeling Shapes of the Homunculus & Little Homunculus: what do we learn about mass ejection? Massive stars: the connection to supernovae, hypernovae and gamma ray bursters Where do we go from here? (future

  17. Stratified X-ray Plasmas around Eta Carinae

    NASA Astrophysics Data System (ADS)

    Hamaguchi, Kenji; Corcoran, Michael

    At a distance of ˜2.3 kpc, eta Carinae is the best super massive star to study the LBV phenomenon. It is a binary composed of two massive stars on a highly elliptical orbit (e ˜0.9-0.95, P˜5.54 years). The current best estimate is that the primary star has M gtrsim90M_{⊙} and v_{wind} ˜420 km s(-1) , while the companion star has M˜30M_{⊙} and v_{wind} ˜3000 km s(-1) . Strong winds from both stars collide (the wind-wind collision: WWC), which produces hot thermal plasmas of kT˜4 keV and emits strong X-rays. The luminosity increases toward periastron, but it abruptly declines by two orders of magnitudes around periastron. We had an observing campaign of eta Car around periastron in 2009.0, which revealed that the X-ray decline is caused by a hybrid mechanism of a true eclipse and an activity decay of the WWC plasma. During the activity decay, the head-on wind collision seems to shut off, possibly due to the overwhelming momentum of the primary wind. The secondary winds flowing backward may still collide with the twisted primary winds and produce hot X-ray plasma. During the eclipse of the WWC plasma, faint X-ray emission from a different plasma component within ˜500 AU from eta Car emerged. The plasma is as hot as the WWC plasma (˜50 MK) and in strong non-equilibrium ionization state (nt ≤sssim4×10(10) cm(-3) s). The plasma may originate from collision of winds ejected a few orbits ago. Inside the bipolar lobe of eta Car, the Chandra observatory spatially resolved emission from extended hot cool (˜6 MK) plasmas, as well as the X-ray reflection component. The spectrum showed unusually strong lines around the Si and S K-shell energies, which may be originated in the collision of the secondary winds with cold circumstellar material. We discuss the circumstellar hot plasma structures of LBVs based on these results.

  18. Eta Carinae and the Homunculus: A Physics Laboratory

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Fisher, Richard R. (Technical Monitor)

    2002-01-01

    The Luminous Blue Variable, Eta Carinae, and its ejecta, thrown out since the 1840s, are proving to be a very challenging system to explain. The > 100 solar mass central source (which is likely a binary system) is very complex with P-Cygni lines throughout the spectrum. Superimposed upon the stellar spectrum are many thousands of narrow absorption lines. Indeed we have found twenty different velocities between -140km/s and -580km/s with many lower levels well elevated above the ground states of numerous ions.

  19. FINAL TECHNICAL REPORT FOR DE-FG02-05ER64097 Systems and Methods for Injecting Helium Beams into a Synchrotron Accelerator

    SciTech Connect

    Bush, David A

    2008-09-30

    A research grant was approved to fund development of requirements and concepts for extracting a helium-ion beam at the LLUMC proton accelerator facility, thus enabling the facility to better simulate the deep space environment via beams sufficient to study biological effects of accelerated helium ions in living tissues. A biologically meaningful helium-ion beam will be accomplished by implementing enhancements to increase the accelerator's maximum proton beam energy output from 250MeV to 300MeV. Additional benefits anticipated from the increased energy include the capability to compare possible benefits from helium-beam radiation treatment with proton-beam treatment, and to provide a platform for developing a future proton computed tomography imaging system.

  20. Scalar mesons in the decays {eta}' {sup {yields}}3{pi}{sup 0} and {eta}' {sup {yields} {pi}0{pi}+{pi}-}

    SciTech Connect

    Likhoded, A. K. Luchinsky, A. V. Samoylenko, V. D.

    2010-10-15

    The decays {eta} {sup {yields}}3{pi}{sup 0} and {eta} {sup {yields} {pi}0{pi}+{pi}-} are considered within the isobar model. It is shown that, in order to explain the branching ratio and the shape of the Dalitz plot for the decay {eta}' {sup {yields}}3{pi}{sup 0}, it is sufficient to take into account the contributions of the {sigma} and a{sub 0} mesons. The inclusion of the {sigma} meson is necessary for reproducing the shape of the distribution over the Dalitz plot. The branching ratio for the decay {eta}' {sup {yields} {pi}0{pi}+{pi}-} is obtained. The predictions for the distributions over the Dalitz plot for this decay are presented. These predictions depend strongly on model parameters.

  1. 77 FR 2089 - Proposed Information Collection Request of the ETA 204, Experience Rating Report; Comment Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ..., telephone number (202) 693-2927 (this is not a toll-free number) or by email: dullaghan.edward@dol.gov... different experience rating systems. Used in conjunction with other data, the ETA-204 assists in determining... and Training Administration (ETA). Title: Experience Rating Report. OMB Number: 1205-0164....

  2. 76 FR 27090 - Comment Request for Extension of Information Collection (Without Revisions): Form ETA 9033-A...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... Revisions): Form ETA 9033-A, Attestation by Employers Using Alien Crewmembers for Longshore Activities in... collection by Form ETA 9033-A, OMB Control Number 1205-0352, Attestation by Employers Using Alien Crewmembers.... The INA generally prohibits the performance of longshore work by alien crewmembers, however the...

  3. 78 FR 40194 - Proposed Information Collection Request of the ETA 207, Nonmonetary Determination Activities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-03

    ... Determination Activities Report; Comment Request on Extension Without Change (OMB 1205-0150) AGENCY: Employment....Edward@dol.gov . SUPPLEMENTARY INFORMATION: I. Background The ETA 207 Report, Nonmonetary Determination... concerning the proposed extension collection of the ETA 207, Nonmonetary Determinations Activities...

  4. Observation of eta'c production in gammagamma fusion at CLEO.

    PubMed

    Asner, D M; Dytman, S A; Mehrabyan, S; Mueller, J A; Nam, S; Savinov, V; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shibata, E I; Shipsey, I P J; Adams, G S; Chasse, M; Cummings, J P; Danko, I; Napolitano, J; Cronin-Hennessy, D; Park, C S; Park, W; Thayer, J B; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Stroynowski, R; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Haynes, J; Menaa, N; Mountain, R; Muramatsu, H; Nandakumar, R; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, Kevin; Mahmood, A H; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Weinstein, A J; Mahapatra, R; Nelson, H N; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Adam, N E; Alexander, J P; Berkelman, K; Boisvert, V; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Patterson, J R; Pedlar, T K; Peterson, D; Pivarski, J; Riley, D; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Sun, W M; Thayer, J G; Urner, D; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stoeck, H; Yelton, J; Eisenstein, B I; Gollin, G D; Karliner, I; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Besson, D; Gao, K Y; Gong, D T; Kubota, Y; Li, S Z; Poling, R; Scott, A W; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Arms, K; Eckhart, E; Gan, K K; Gwon, C; Severini, H; Skubic, P

    2004-04-01

    We report on the observation of the eta(')(c)(2(1)S0), the radial excitation of the eta(c)(1(1)S0) ground state of charmonium, in the two-photon fusion reaction gammagamma-->eta(')(c)-->K(0)(S)K+/-pi(-/+) in 13.6 fb(-1) of CLEO II/II.V data and 13.1 fb(-1) of CLEO III data. We obtain M(eta(')(c))=3642.9+/-3.1(stat)+/-1.5(syst) MeV and M(eta(c))=2981.8+/-1.3(stat)+/-1.5(syst) MeV. The corresponding values of hyperfine splittings between 1S0 and 3S1 states are DeltaM(hf)(1S)=115.1+/-2.0 MeV and DeltaM(hf)(2S)=43.1+/-3.4 MeV. Assuming that the eta(c) and eta(')(c) have equal branching fractions to K(S)Kpi, we obtain Gamma(gammagamma)(eta(')(c))=1.3+/-0.6 keV. PMID:15089529

  5. 77 FR 35060 - Employment and Training Administration; Proposed Information Collection Request for the ETA 538...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... addresses section below on or before August 13, 2012. ADDRESSES: Submit written comments to Scott Gibbons... toll-free Federal Information Relay Service at 1-877-889-5627 (TTY/TDD). Email: gibbons.scott@dol.gov.... Gibbons. SUPPLEMENTARY INFORMATION: I. Background The ETA 538 and ETA 539 reports are weekly reports...

  6. Cautionary Note on Reporting Eta-Squared Values from Multifactor ANOVA Designs

    ERIC Educational Resources Information Center

    Pierce, Charles A.; Block, Richard A.; Aguinis, Herman

    2004-01-01

    The authors provide a cautionary note on reporting accurate eta-squared values from multifactor analysis of variance (ANOVA) designs. They reinforce the distinction between classical and partial eta-squared as measures of strength of association. They provide examples from articles published in premier psychology journals in which the authors…

  7. USING MM5V3 WITH ETA ANALYSES FOR AIR-QUALITY MODELING AT THE EPA

    EPA Science Inventory

    Efforts have been underway since MM5v3 was released in July 1999 to set up air-quality simulations using Eta analyses as background fields. Our previous simulations used a one-way quadruple-nested set of domains with horizontal grid spacing of 108, 36, 12 and 4 km. With Eta a...

  8. 76 FR 58540 - Proposed Information Collection Request of the ETA 581, Contribution Operations Report; Extension...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... Performance System (TPS) which evaluates the employer-related or tax functions of the UI program. The... measuring the performance and effectiveness of states' UI tax operations. Using ETA 581 data, the TPS... report is the only vehicle for collection of information required under the TPS program. If ETA 581...

  9. A new class of simplified phorbol ester analogues: synthesis and binding to PKC and eta PKC-C1B (eta PKC-CRD2).

    PubMed

    Wender, P A; Kirschberg, T A; Williams, P D; Bastiaans, H M; Irie, K

    1999-10-01

    [formula: see text] A unique class of simplified phorbol ester analogues is described for the first time. A highly efficient retro-annelation sequence was developed in order to remove the five-membered ring from the phorbol diterpene core, allowing access to BCD ring analogues of the phorbol esters. The binding of these analogues to protein kinase C (PKC) and the truncated peptide eta PKC-C1B (eta PKC-CRD2) is also reported. PMID:10825954

  10. On Decays of B Mesons to a Strange Meson and an Eta or Eta' Meson at Babar

    SciTech Connect

    Hirschauer, James Francis

    2009-01-01

    We describe studies of the decays of B mesons to final states ηK*(892), ηK*0(S-wave), ηK*2(1430), and η'K based on data collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collier at the Stanford Linear Accelerator Center. We measure branching fractions and charge asymmetries for the decays B → ηK*, where K* indicates a spin 0, 1, or 2 Kπ system, making first observations of decays to final states ηK0*0(S-wave), ηK+*0 (S-wave), and ηK0*2(1430). We measure the time-dependent CP-violation parameters S and C for the decays B0 → η'K0, observing CP violation in a charmless B decay with 5σ significance considering both statistical and systematic uncertainties.

  11. SECULAR CHANGES IN ETA CARINAE'S WIND 1998-2011

    SciTech Connect

    Mehner, Andrea; Davidson, Kris; Humphreys, Roberta M.; Ishibashi, Kazunori; Martin, John C.; Ruiz, Maria Teresa; Walter, Frederick M.

    2012-05-20

    Stellar wind-emission features in the spectrum of eta Carinae have decreased by factors of 1.5-3 relative to the continuum within the last 10 years. We investigate a large data set from several instruments (STIS, GMOS, UVES) obtained between 1998 and 2011 and analyze the progression of spectral changes in direct view of the star, in the reflected polar-on spectra at FOS4, and at the Weigelt knots. We find that the spectral changes occurred gradually on a timescale of about 10 years and that they are dependent on the viewing angle. The line strengths declined most in our direct view of the star. About a decade ago, broad stellar wind-emission features were much stronger in our line-of-sight view of the star than at FOS4. After the 2009 event, the wind-emission line strengths are now very similar at both locations. High-excitation He I and N II absorption lines in direct view of the star strengthened gradually. The terminal velocity of Balmer P Cyg absorption lines now appears to be less latitude dependent, and the absorption strength may have weakened at FOS4. Latitude-dependent alterations in the mass-loss rate and the ionization structure of eta Carinae's wind are likely explanations for the observed spectral changes.

  12. Recurrent X-ray Emission Variations of Eta Carinae and the Binary Hypothesis

    NASA Technical Reports Server (NTRS)

    Ishibashi, K.; Corcoran, M. F.; Davidson, K.; Swank, J. H.; Petre, R.; Drake, S. A.; Damineki, A.; White, S.

    1998-01-01

    Recent studies suggest that, the super-massive star eta Carinae may have a massive stellar companion (Damineli, Conti, and Lopes 1997), although the dense ejecta surrounding the star make this claim hard to test using conventional methods. Settling this question is critical for determining the current evolutionary state and future evolution of the star. We address this problem by an unconventional method: If eta Carinae is a binary, X-ray emission should be produced in shock waves generated by wind-wind collisions in the region between eta Carinae and its companion. Detailed X-ray monitoring of eta Carinae for more that) 2 years shows that the observed emission generally resembles colliding-wind X-ray emission, but with some significant discrepancies. Furthermore, periodic X-ray "flaring" may provide an additional clue to determine the presence of a companion star and for atmospheric pulsation in eta Carinae.

  13. Near-Field ETAS Constraints and Applications to Seismic Hazard Assessment

    NASA Astrophysics Data System (ADS)

    Yoder, Mark R.; Rundle, John B.; Glasscoe, Margaret T.

    2015-08-01

    The epidemic type aftershock sequence (ETAS) statistical model of aftershock seismicity combines various earthquake scaling relations to produce synthetic earthquake catalogs, or estimates of aftershock seismicity rates, based on recent earthquake activity. One challenge to ETAS-based hazard assessment is the large number of free parameters involved. In this paper, we introduce an approach to constrain this parameter space from canonical scaling relations, empirical observations, and fundamental physics. We show that ETAS parameters can be estimated as a function of an earthquake's magnitude m based on the finite temporal and spatial extents of the rupture area. This approach facilitates fast ETAS-based estimates of seismicity from large "seed" catalogs, and it is particularly well suited to web-based deployment and otherwise automated implementations. It constitutes a significant improvement over contemporary ETAS by mitigating variability related to instrumentation and subjective catalog selection.

  14. Reactions and moderators for an accelerator-based epithermal neutron capture therapy source for cancer treatment. Final report, October 1900--September 1994

    SciTech Connect

    Kunze, J.F.; Brugger, R.M.

    1995-03-01

    The use of boron neutron capture therapy (BNCT) has been considered for nearly 30 years, and been practiced in Japan since the late 1970`s. Early experiments in the USA were generally nonpromising. However, new boron-containing ligand compounds were developed, which would seek out brain tumors. Concentration levels of the order of 30 micrograms of boron per gram of tissue become possible, and interest in the BNCT technique was revived in the USA beginning about 1985, with research reactors as the obvious source of the neutrons for the treatment. However, the limited number of research reactors in the USA (and the world) would mean that this treatment modality would be quite limited. The goals of this work was: (1) Examine as many as possible reactions of charged particles on various targets of an accelerator, and determine those that would give high neutron yields of a convenient energy. (2) Determine, through calculations (using Monte Carlo stochastic computer codes), the best design for a moderator/reflector assembly which would give high thermal flux at a nominal 5 cm depth in the head of a patient, with minimal radiation dose from gamma rays and fast neutrons. (3) Perform a benchmark experiment using a positive ion accelerator. The Li-7(p,n) reaction was chosen for the benchmark, since it was readily available for most accelerators, and was one of the two highest yielding reactions from Task No. 1. Since the University of Missouri has no accelerator, possible accelerators at other universities were investigated, as to availability and cost. A unit having capability in the 2.5 MeV range was desired.

  15. Lewis acid adducts (BH sub 3 , Me sup + , and Et sup + ) of the. eta. sup 4 and. eta. sup 2 isomers of Cp sup * Ir(thiophene)

    SciTech Connect

    Chen, Jiabi; Angelici, R.J. )

    1990-03-01

    The {eta}{sup 4}-thiophene complex Cp{sup *}Ir({eta}{sup 4}-2,5-Me{sub 2}T) (2), where 2,5-Me{sub 2} is 2,5-dimethylthiophene, reacts with Me{sub 2}S{center dot}BH{sub 3} to give the BH{sub 3} adduct Cp{sup *}Ir({eta}{sup 4}-2,5-Me{sub 2}T{center dot}BH{sub 3}) (6), demonstrating the unusually high basicity of the sulfur in 2 as compared with that in Me{sub 2}S. Basic amines remove the BH{sub 3} in 6 to give 2. Surprisingly, the isomer Cp{sup *}Ir({eta}{sup 2}-2,5-Me{sub 2}T) (4) also reacts with Me{sub 2}S{center dot}BH to give 6. The 2-methylthiophene analogues of 2 and 4 react similarly to give Cp{sup *}Ir({eta}{sup 4}-2-MeT{center dot}BH{sub 3}) (5), whose structure was determined by X-ray diffraction. Complex 2 also reacts with R{sub 3}O{sup +} (R = Me, Et) to give the S-alkylated thiophene complexes Cp{sup *}Ir({eta}{sup 4}-2,5-Me{sub 2}T-R){sup +}.

  16. Investigation of near-threshold eta-meson production in the reaction {pi}{sup -}p{yields} {eta}n

    SciTech Connect

    Bayadilov, D. E.; Beloglazov, Yu. A.; Gridnev, A. B.; Kozlenko, N. G.; Kruglov, S. P.; Kulbardis, A. A.; Lopatin, I. V.; Novinskiy, D. V.; Radkov, A. K.; Sumachev, V. V.; Filimonov, E. A.; Shvedchikov, A. V.

    2012-08-15

    Differential and total cross sections for eta-meson production in the reaction {pi}{sup -}p {yields} {eta}n were measured within the experimental program eta-meson physics implemented in the pion channel of the synchrocyclotron of the Petersburg Nuclear Physics Institute (PNPI, Gatchina). These measurements were performed at incident-pion momenta (700, 710, 720, and 730 MeV/c) in the vicinity of the threshold for the process under study by using the neutral-meson spectrometer designed and created at the Meson Physics Laboratory of PNPI. It is shown that, in the immediate vicinity of the threshold (685 MeV/c), the process of eta-meson production proceeds predominantly via S{sub 11}(1535)-resonance formation followed by the decay S{sub 11}(1535) {yields} {eta}n (the respective branching fraction is Br Almost-Equal-To 60%), but that, as the momentum of incident pions increases, the role of the D wave becomes ever more important. A detailed analysis of this effect indicates that it is due to the increasing contribution of the D{sub 13}(1520) resonance. Although the branching fraction of the decay of this resonance through the {eta}n channel is assumed to be very small (BR Almost-Equal-To 0.24%), the effect is enhanced owing to the interference between the D wave and the dominant resonance S{sub 11}(1535).

  17. Branching Ratio Measurements of B ---> J/psi eta K and B+- ---> D0 K+- with D0 ---> pi+ pi- pi0

    SciTech Connect

    Zeng, Qinglin; /Colorado State U.

    2006-03-08

    Results are presented for the decays of B {yields} J/{psi}{eta}K and B{sup {+-}} {yields} DK{sup {+-}}, respectively, with experimental data collected with BABAR detector at PEP-II, located at Stanford Linear Accelerator Center (SLAC). With 90 x 10{sup 6} B{bar B} events at the {Upsilon}(4S) resonance, we obtained branching fractions of {Beta}(B{sup {+-}} {yields} J/{psi}{eta}K{sup {+-}}) = [10.8 {+-} 2.3(stat) {+-} 2.4(syst)] x 10{sup -5} and {Beta}(B{sup 0} {yields} J/{psi}{eta}K{sub S}{sup 0}) = [8.4 {+-} 2.6(stat) {+-} 2.7(syst)] x 10{sup -5}; and we set an upper limit of {Beta}[B{sup {+-}} {yields} X(3872)K{sup {+-}} {yields} J/{psi}{eta}K{sup {+-}}] < 7.7 x 10{sup -6} at 90% confidence level. The branching fraction of decay chain {Beta}(B{sup {+-}} {yields} DK{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}K{sup {+-}}) = [5.5 {+-} 1.0(stat) {+-} 0.7(syst)] x 10{sup -6} with 229 x 10{sup 6} B{bar B} events at {Upsilon}(4S) resonance, here D represents the neutral D meson. The decay rate asymmetry is A = 0.02 {+-} 0.16(stat) {+-} 0.03(syst) for this full decay chain. This decay can be used to extract the unitarity angle {gamma}, a weak CP violation phase, through the interference of decay production of D{sup 0} and {bar D}{sup 0} to {pi}{sup +}{pi}{sup -}{pi}{sup 0}.

  18. Intramolecular coupling of eta/sup 2/-iminoacyl groups at group 4 metal centers: a kinetic study of the carbon-carbon double-bond-forming reaction

    SciTech Connect

    Durfee, L.D.; McMullen, A.K.; Rothwell, I.P.

    1988-03-02

    The series of bis(eta/sup 2/-iminoacyl) compounds of general formula M(OAr)/sub 2/(eta/sup 2/-R'NCR)/sub 2/ (M = Ti, Zr, Hf; OAr = 2,6-diisopropyl- and 2,6-di-tert-butylphenoxide; R = CH/sub 3/, CH/sub 2/Ph; R' = various substituted phenyls) undergo intramolecular coupling on thermolysis to produce the corresponding enediamide derivatives M(OAr)/sub 2/(R'NC(R) = C(R)NR'). A kinetic study of the reaction in hydrocarbon solvents has shown it to be first order. The reaction is metal dependent with the rate decreasing in the order Ti > Zr > Hf. The rate of the reaction is also dependent on the steric and electronic nature of the nitrogen substituent (R'). The use of the bulky aryl group 2,6-dimethylphenyl retards the reaction, while the use of various 3- and 4-substituted phenyls (3-F, 3-OMe, 4-OMe, 4-Cl, 4-NMe/sub 2/) shows the reaction to be accelerated by electron-withdrawing substituents. A sigma plot based on kinetic data obtained at 67/sup 0/C and 77/sup 0/C yielded rho values of 0.83 (R = 0.97) and 0.84 (R = 0.95), respectively. Both the steric and electronic dependence of the reactivity on the nitrogen substituents is discussed mechanistically and used to rationalize the much more facile intramolecular coupling observed for the related eta/sup 2/-acyl (eta/sup 2/-OCR) functionalities.

  19. HEAVY ION LINEAR ACCELERATOR

    DOEpatents

    Van Atta, C.M.; Beringer, R.; Smith, L.

    1959-01-01

    A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

  20. Time resolved, 2-D hard X-ray imaging of relativistic electron-beam target interactions on ETA-II

    SciTech Connect

    Crist, C.E.; Sampayan, S.; Westenskow, G.; Caporaso, G.; Houck, T.; Weir, J.; Trimble, D.; Krogh, M.

    1998-11-01

    Advanced radiographic applications require a constant source size less than 1 mm. To study the time history of a relativistic electron beam as it interacts with a bremsstrahlung converter, one of the diagnostics they use is a multi-frame time-resolved hard x-ray camera. They are performing experiments on the ETA-II accelerator at Lawrence Livermore National Laboratory to investigate details of the electron beam/converter interactions. The camera they are using contains 6 time-resolved images, each image is a 5 ns frame. By starting each successive frame 10 ns after the previous frame, they create a 6-frame movie from the hard x-rays produced from the interaction of the 50-ns electron beam pulse.

  1. Analytic approach to nonlinear hydrodynamic instabilities driven by time-dependent accelerations

    SciTech Connect

    Mikaelian, K O

    2009-09-28

    We extend our earlier model for Rayleigh-Taylor and Richtmyer-Meshkov instabilities to the more general class of hydrodynamic instabilities driven by a time-dependent acceleration g(t) . Explicit analytic solutions for linear as well as nonlinear amplitudes are obtained for several g(t)'s by solving a Schroedinger-like equation d{sup 2}{eta}/dt{sup 2} - g(t)kA{eta} = 0 where A is the Atwood number and k is the wavenumber of the perturbation amplitude {eta}(t). In our model a simple transformation k {yields} k{sub L} and A {yields} A{sub L} connects the linear to the nonlinear amplitudes: {eta}{sup nonlinear} (k,A) {approx} (1/k{sub L})ln{eta}{sup linear} (k{sub L}, A{sub L}). The model is found to be in very good agreement with direct numerical simulations. Bubble amplitudes for a variety of accelerations are seen to scale with s defined by s = {integral} {radical}g(t)dt, while spike amplitudes prefer scaling with displacement {Delta}x = {integral}[{integral}g(t)dt]dt.

  2. Accelerated test methods for life prediction of hermetic motor insulation systems exposed to alternative refrigerant/lubricant mixtures. Phase 3: Reproducibility and discrimination testing. Final report

    SciTech Connect

    Ellis, P.F. II; Ferguson, A.F.; Fuentes, K.T.

    1996-05-06

    In 1992, the Air-Conditioning and Refrigeration Technology Institute, Inc. (ARTI) contracted Radian Corporation to ascertain whether an improved accelerated test method or procedure could be developed that would allow prediction of the life of motor insulation materials used in hermetic motors for air-conditioning and refrigeration equipment operated with alternative refrigerant/lubricant mixtures. This report presents the results of phase three concerning the reproducibility and discrimination testing.

  3. Final Report for grant DE-FG02-06ER54888, "Simulation of Beam-Electron Cloud Interactions in Circular Accelerators Using Plasma Models"

    SciTech Connect

    Decyk, Viktor K

    2012-11-27

    The primary goal of this collaborative proposal was to modify the code QuickPIC and apply it to study the long-time stability of beam propagation in low density electron clouds present in circular accelerators. The UCLA contribution to this collaborative proposal was in supporting the development of the pipelining scheme for the QuickPIC code, which extended the parallel scaling of this code by two orders of magnitude.

  4. Acceleration of polarized protons in circular accelerators

    SciTech Connect

    Courant, E.D.; Ruth, R.D.

    1980-09-12

    The theory of depolarization in circular accelerators is presented. The spin equation is first expressed in terms of the particle orbit and then converted to the equivalent spinor equation. The spinor equation is then solved for three different situations: (1) a beam on a flat top near a resonance, (2) uniform acceleration through an isolated resonance, and (3) a model of a fast resonance jump. Finally, the depolarization coefficient, epsilon, is calculated in terms of properties of the particle orbit and the results are applied to a calculation of depolarization in the AGS.

  5. A Measurement of the B ---> Eta/C K Branching Fraction Using the BaBar Detector

    SciTech Connect

    Jackson, Frank; /Manchester U.

    2006-04-26

    The branching fraction is measured for the decay channels B{sup 0} {yields} {eta}{sub c}K{sub S}{sup 0} and B{sup +} {yields} {eta}{sub c}K{sup +} where {eta}{sub c} {yields} K{bar K}{pi}, using the BABAR detector. The {eta}{sub c} {yields} K{sub S}{sup 0}K{sup +}{pi}{sup -} and {eta}{sub c} {yields} K{sup +}K{sup -}{pi}{sup 0} decay channels are used, including non-resonant decays and possibly those through intermediate resonances.

  6. Constraining the polarization of the proton's glue with the eta meson

    NASA Astrophysics Data System (ADS)

    Seele, Joseph

    The division of the proton's spin among its quarks and gluons is a fundamental question in modern nuclear physics. The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) is measuring asymmetries in polarized proton-proton collisions at s = 200 GeV to garner information about the polarizations of the quarks and gluons. Measurements of the double helicity asymmetry for high pT mid-rapidity eta meson production in proton-proton collisions at s = 200 GeV are presented in this work. In order to obtain information about the polarizations of the quarks and gluons in the proton using the eta meson, the eta meson fragmentation functions must be known. No set existed, therefore a first global fit to the eta meson fragmentation functions was performed. The fit benefits from the inclusion of measurements of the cross section for eta meson production in proton-proton collisions. Therefore, a measurement of the cross section for high pT mid-rapidity eta meson production in proton-proton collisions at s = 200 GeV is performed to aid the fit. With the eta fragmentation functions, the measurement of the double helicity asymmetry is used to constrain the contribution of the spins of the gluons to the spin of the proton. Using a model and the work in this thesis, an estimate of the gluon contribution to the proton's spin is calculated and compared to other evaluations.

  7. Measurement of the branching fraction for $\\tau\\to\\eta K\

    SciTech Connect

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2011-08-12

    The authors report on analyses of tau lepton decays {tau}{sup -} {yields} {eta}K{sup -}{nu}{sub {tau}} and {tau}{sup -} {yields} {eta}{pi}{sup -}{nu}{sub {tau}}, with {eta} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}, using 470 fb{sup -1} of data from the BABAR experiment at PEP-II, collected at center-of-mass energies at and near the {Upsilon}(4S) resonance. They measure the branching fraction for the {tau}{sup -} {yields} {eta}K{sup -}{nu}{sub {tau}} decay mode, {Beta}({tau}{sup -} {yields} {eta}K{sup -}{nu}{sub {tau}}) = (1.42 {+-} 0.11(stat) {+-} 0.07(syst)) x 10{sup -4}, and report a 95% confidence level upper limit for the second-class current process {tau}{sup -} {yields} {eta}{pi}{sup -}{nu}{sub {tau}}, {Beta}({tau}{sup -} {yields} {eta}{pi}{sup -}{nu}{sub {tau}}) < 9.9 x 10{sup -5}.

  8. Model Error Estimation for the CPTEC Eta Model

    NASA Technical Reports Server (NTRS)

    Tippett, Michael K.; daSilva, Arlindo

    1999-01-01

    Statistical data assimilation systems require the specification of forecast and observation error statistics. Forecast error is due to model imperfections and differences between the initial condition and the actual state of the atmosphere. Practical four-dimensional variational (4D-Var) methods try to fit the forecast state to the observations and assume that the model error is negligible. Here with a number of simplifying assumption, a framework is developed for isolating the model error given the forecast error at two lead-times. Two definitions are proposed for the Talagrand ratio tau, the fraction of the forecast error due to model error rather than initial condition error. Data from the CPTEC Eta Model running operationally over South America are used to calculate forecast error statistics and lower bounds for tau.

  9. UNEXPECTED IONIZATION STRUCTURE IN ETA CARINAE'S ''WEIGELT KNOTS''

    SciTech Connect

    Remmen, Grant N.; Davidson, Kris; Mehner, Andrea

    2013-08-10

    The Weigelt knots, dense slow-moving ejecta near {eta} Carinae, are mysterious in structure as well as in origin. Using spatially dithered spectrograms obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS), we have partially resolved the ionization zones of one knot. Contrary to simple models, higher ionization levels occur on the outer side, i.e., farther from the star. They cannot represent a bow shock, and no satisfying explanation is yet available-though we sketch one qualitative possibility. STIS spectrograms provide far more reliable spatial measurements of the Weigelt knots than HST images do, and this technique can also be applied to the knots' proper motion problem. Our spatial measurement accuracy is about 10 mas, corresponding to a projected linear scale of the order of 30 AU, which is appreciably smaller than the size of each Weigelt knot.

  10. The -145 km/S Absorption System of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Vieira, G.; Gull, T. R.; Danks, A.; Johansson, S.

    2002-01-01

    With the STIS E230H mode (R-118,000) , we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 W s , are quite different in character from the others, mostly at intermediate velocities. The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000/cm, well above the 2000/cm noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes.

  11. Recovery from a Giant Eruption: The Case of Eta Car

    NASA Astrophysics Data System (ADS)

    Davidson, Kris; Mehner, Andrea; Martin, John C.; Humphreys, Roberta M.

    2016-01-01

    Giant eruptions or SN Impostors are far more mysterious than "real" supernovae, because they are scarcer and because they have received far less theoretical effort. One rather special problem is the disequilibrium state of the post-eruption object. It may be partially observable by watching the star's gradual recovery; which, in principle, may offer clues to the basic instability mechanisms. So far, the only example that can be observed well enough is eta Carinae. This object's history offers tantalizing clues and counter-clues. For instance: (1) Before 2000, the recovery timescale seemed to be of order 150 years; but (2) around 2000, many attributes began to change much more rapidly; and (3) the 150-year recovery process has been punctuated by about three abrupt changes of state. This strange combination of facts has received almost no theoretical attention.

  12. Understanding the X-ray Flaring from Eta Carinae

    NASA Technical Reports Server (NTRS)

    Moffat, A.F.J.; Corcoran, Michael F.

    2009-01-01

    We quantify the rapid variations in X-ray brightness ("flares") from the extremely massive colliding wind binary Eta Carinae seen during the past three orbital cycles by RXTE. The observed flares tend to be shorter in duration and more frequent as periastron is approached, although the largest ones tend to be roughly constant in strength at all phases. Plausible scenarios include (1) the largest of multi-scale stochastic wind clumps from the LBV component entering and compressing the hard X-ray emitting wind-wind collision (WWC) zone, (2) large-scale corotating interacting regions in the LBV wind sweeping across the WWC zone, or (3) instabilities intrinsic to the WWC zone. The first one appears to be most consistent with the observations, requiring homologously expanding clumps as they propagate outward in the LBV wind and a turbulence-like powerlaw distribution of clumps, decreasing in number towards larger sizes, as seen in Wolf-Rayet winds.

  13. The Ejecta of Eta Carinae as Studied by STIS

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Oegerle, William R. (Technical Monitor)

    2002-01-01

    The Space Telescope Imaging Spectrograph has been used to study the emission and absorption spectra of ejecta surrounding Eta Carinae. Discussion will be presented on the overall structure of the Homunculus, the Weigelt blobs and the Strontium filament. Three visits have been accomplished with the Position Angle precisely the same and covering the Central Source and Weigelt Blobs B and D. Deep spectra have been done at several positions to obtain the overall velocity structure of the Homunculus and the disk region. Mapping has been done with the STIS medium dispersion gratings set near H beta and H alpha. We have obtained full coverage of the strontium filament from 1640 Angstroms to 10300 Angstroms. The structure and physical properties will be described.

  14. The homunculus of Eta Carinae: An interacting stellar winds paradigm

    NASA Technical Reports Server (NTRS)

    Frank, Adam; Balick, Bruce; Davidson, Kris

    1995-01-01

    We simulate the origin and evolution of the bipolar nebula surrounding Eta Car using numerical two-dimensional gasdynamic models. The generalized interacting stellar winds scenario, wherein a stellar wind interacts with an aspherical circumstellar environment, is adopted. The eruption wind of 1840-1860, which is taken to be spherically symmetric, interacts with a preeruption toroidal density environment. Using reasonable assumptions of initial conditions and eruption parameters based on archival data, we have performed over 30 simulations in an effort to bracket the initial parameters which produce models that best match observations. We find that models with high pole-to-equator density contrasts (greater than 100) and toroidal density configurations nicely account for the observed morphology and kinematics of the homunculus.

  15. Little Homunculus with in the Homunculus of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Ishibashi, Kazunori; Gull, Theodore R.; Davidson, Kris; Fisher, Richard R. (Technical Monitor)

    2000-01-01

    The famous HST/WFPC2 images of Eta Carinae provide a two-dimensional projection of the bipolar nebula that is really a three-dimensional structure. Much is hidden in subtle, projected details that a velocity-tuned instrument can pull apart. We have used the HST/STIS with a 52" x 0.1" aperture and with about 5000 spectral resolving power to examine the kinetic information contained within emission/absorption features. By velocity tuning, we can translate this information into spatial structures. The spectroscopic datasets have been transformed to a set of images, spaced at half instrumental line width steps, 15 - 20 km/s , and with a spatial resolution of 0.1 x 0.1 arcsec near Balmer beta and 0.25 x 0.1 arcsec near Balmer alpha. We examined these narrow-band images and individual spectra to characterize the nature of an internal nebula (formerly known as the Integral nebula). The shape of this nebulosity is an bipolar nebula, deeply embedded within the Homunculus, the well-known bipolar nebula surrounding Eta Carinae. The internal nebula is shaped nearly identically to the Homunculus. It is best described as a "little Homunculus within the Homunculus". Indeed, it is reminiscent of the Russian dolls, known as Matryoshka dolls, that successively nest within each larger doll. For that reason, we call this internal nebula the Matryoshka nebula. This was performed as one of the STIS GTO key projects and was funded by the HST project. Observations were done through the STScI.

  16. The Time Evolution of Eta Carinae's Colliding Winds

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Madura, T. I.; Grobe, J. H.; Corcoran, M. F.

    2011-01-01

    We report new HST/STIS observations that map the high-ionization forbidden line emission in the inner arc second of Eta Car, the first that fully image the extended wind-wind interaction region of the massive colliding wind binary. These observations were obtained after the 2009.0 periastron at orbital phases 0.084, 0.163, and 0.323 of the 5.54-year spectroscopic cycle. We analyze the variations in brightness and morphology of the emission, and find that blue-shifted emission (-400 to -200 km/s is symmetric and elongated along the northeast-southwest axis, while the red-shifted emission (+ 100 to +200 km/s) is asymmetric and extends to the north-northwest. Comparison to synthetic images generated from a 3-D dynamical model strengthens the 3-D orbital orientation found by Madura et al. (2011), with an inclination i = 138 deg, argument of periapsis w = 270 deg, and an orbital axis that is aligned at the same P A on the sky as the symmetry axis of the Homunculus, 312 deg. We discuss the potential that these and future mappings have for constraining the stellar parameters of the companion star and the long-term variability of the system. Plain-Language Abstract: With HST, we resolved the interacting winds of the binary, Eta Carinae. With a 3-D model, we find the binary orbit axis is aligned to the Homunculus axis. This suggests a connection between the binary and Homunculus ejection mechanism.

  17. Construction of. gamma pi. /sup 0/ spectrometer and photon tagging facility at Bates Linear Accelerator. Final report, July 31, 1979-July 31, 1980

    SciTech Connect

    Booth, E.C.

    1981-08-01

    The funds provided under Contract No. DE-AC02-79ER10486 were totally expended for hardware and supplies required by two related devices at the Bates Linear Accelerator. These were a photon tagging facility and a ..gamma pi../sup 0/ spectrometer in Beam Line C of the new South Experimental Hall. Construction was begun in November of 1979 and both systems became fully operational in the summer of 1981. Preliminary data was taken in 1980 with a prototype ..gamma pi../sup 0/ spectrometer will be carried out in the fall of 1981 and spring of 1982. The photon tagging system has been used successfully to calibrate the ..gamma pi../sup 0/ spectrometer for the BU - MIT collaboration and to test a lead glass detector system for Brandeis University.

  18. Accelerated life test of the USDOE OC-OTEC experimental system refurbished with magnetic bearings for the 3rd stage vacuum compressor. Final report

    SciTech Connect

    Vega, L.A.

    1997-04-01

    This report documents the accelerated life test (time-to-failure) performed, at the request of DOE, to evaluate the viability of the magnetic bearing system installed in the stage 3 vacuum pump. To this effect the plant was successfully operated for over 500 hours during the period September-November 1996. The first part of this report discusses system performance by deriving subsystem and system performance parameters from a typical record. This is followed by the discussion of the life tests. The instrumentation used to estimate the performance parameters given here is depicted. The third stage pump was operated for 535 hours without incident. It is concluded that magnetic bearings are the preferable choice for the OC-OTEC centrifugal vacuum pumps.

  19. Further Investigation Of The Winds Of Eta Car A And B

    NASA Astrophysics Data System (ADS)

    Nielsen, Krister E.; Corcoran, M. F.; Gull, T. R.; Hamaguchi, K.; Hillier, D. J.; Weis, K.

    2007-12-01

    A majority of all observations of Eta Car supports the suggested duality of the system, but the conditions in the inner core of the nebula and, especially, the character of Eta Car B, evade direct measurements. We utilize VLT/UVES spectra obtained either by observing the system in line-of-sight towards the stellar system; or via radiation reflected by the Homunculus. These additional vantage points provide information about the inhomogeneous and non-symmetric winds from the central objects, and how the system changes with orbital phase. We investigate the excitation/ionization conditions by tracing transitions with different spectral characteristics over the 5.54 yr orbital period. The nebular-scattered line profiles are compared with corresponding high-angular resolution HST/STIS observations in line-of-sight towards the Eta Car binary. The line dependent behavior, provides additional information in the quest to understand the Eta Car binary and its close environment.

  20. Recalculation of the coupling constants g{sub {rho}{eta}{gamma},} g{sub {omega}{eta}{gamma},} g{sub {eta}}{sup '}{sub {rho}{gamma},} and g{sub {eta}'{omega}{gamma}}in QCD sum rules

    SciTech Connect

    Aydin, C.; Yilmaz, A. H.; Bayar, M.

    2010-05-01

    We recalculated the coupling constants of {rho}({omega}){yields}{eta}{gamma} and {eta}{sup '{yields}{rho}}({omega}){gamma} decays especially with loop contributions in the case of axial-vector coupling in the method of QCD sum rules for dimension d=6. A comparison of our prediction on the coupling constants with the result obtained from analysis of the experimental data and calculations done before is performed.

  1. Bias in fitting the ETAS model: a case study based on New Zealand seismicity

    NASA Astrophysics Data System (ADS)

    Harte, D. S.

    2013-01-01

    We fit various forms of the ETAS model to a large region that includes all of the most seismically active areas of New Zealand. The ETAS model contains two components: a component describing background or immigrant events, and a part describing aftershocks of the background events and aftershocks of the aftershocks. We refer to the first part as the background part and the second as the ETAS part. Generally all of the sophistication, and the bulk of the model parameters, lies in the ETAS part of the model. The background component is generally treated as a nuisance component and is often very simplistic. While the main interest lies in the ETAS part of the model, the poor model description of the background part imposes considerable bias on the ETAS part of the model. For example, a poorly specified spatial density of the background events causes many of the background events to be seen as ETAS events. It can also cause the estimated Omori power-law decay p to be too small, and hence the aftershock sequences appear to continue for too long. On the other hand, the boundary of the observation region can impose a reverse bias which causes aftershocks that are close but within the boundary to be seen as background events. In almost all of the large NZ event sequences since 1965, the model consistently under-fits these sequences. Consequently, it over-fits those space-time regions where there is `normal' seismicity with no major events present. This may indicate that the space-time region of a major event sequence is much closer to criticality, in that aftershock events appear to be much more easily initiated. The standard ETAS model does not reflect this observation.

  2. PKC{eta} is a negative regulator of AKT inhibiting the IGF-I induced proliferation

    SciTech Connect

    Shahaf, Galit; Rotem-Dai, Noa; Koifman, Gabriela; Raveh-Amit, Hadas; Frost, Sigal A.; Livneh, Etta

    2012-04-15

    The PI3K-AKT pathway is frequently activated in human cancers, including breast cancer, and its activation appears to be critical for tumor maintenance. Some malignant cells are dependent on activated AKT for their survival; tumors exhibiting elevated AKT activity show sensitivity to its inhibition, providing an Achilles heel for their treatment. Here we show that the PKC{eta} isoform is a negative regulator of the AKT signaling pathway. The IGF-I induced phosphorylation on Ser473 of AKT was inhibited by the PKC{eta}-induced expression in MCF-7 breast adenocarcinoma cancer cells. This was further confirmed in shRNA PKC{eta}-knocked-down MCF-7 cells, demonstrating elevated phosphorylation on AKT Ser473. While PKC{eta} exhibited negative regulation on AKT phosphorylation it did not alter the IGF-I induced ERK phosphorylation. However, it enhanced ERK phosphorylation when stimulated by PDGF. Moreover, its effects on IGF-I/AKT and PDGF/ERK pathways were in correlation with cell proliferation. We further show that both PKC{eta} and IGF-I confer protection against UV-induced apoptosis and cell death having additive effects. Although the protective effect of IGF-I involved activation of AKT, it was not affected by PKC{eta} expression, suggesting that PKC{eta} acts through a different route to increase cell survival. Hence, our studies show that PKC{eta} provides negative control on AKT pathway leading to reduced cell proliferation, and further suggest that its presence/absence in breast cancer cells will affect cell death, which could be of therapeutic value.

  3. A fast cyber 205-ETA 10 program for SU(3) lattice gauge theory

    NASA Astrophysics Data System (ADS)

    Vohwinkel, Claus; Berg, Bernd A.; Devoto, Alberto

    1988-11-01

    We describe a Monte Carlo program that simulates SU(3) lattice gauge theoryon CYBER 205 and ETA 10 computers. The program uses the Cabibbo Marinari algorithm for the updating and a novel way of gathering neighbors. It achieves a 17.1 μs updating time per link on a 2-pipe CYBER 205 using 32-bit arithmetic. The updating time per link on the ETA 10 at Florida State University is 8.8 μs.

  4. Magnetic eta index and the ability to forecast sporadic E layer appearance

    NASA Astrophysics Data System (ADS)

    Dziak-Jankowska, Beata; Stanislawska, Iwona; Pozoga, Mariusz; Tomasik, Lukasz; Ernst, Tomasz

    2012-07-01

    We analysed the correlation of the changes of the magnetic vertical component with the ionospheric deviations from monthly median of the E layer characteristics. Promising results indicate that the eta parameter can be used to predict sporadic E layer during magnetically quiet days. Our previous work concern the data from only one year - 2004. During the descending phase of solar cycle in 2004 there was not numerous amount of quiet days. We extend our research to other years starting from 1996 and focusing on 2007 - 2009, years of the prolonged solar minimum. The analysis shows that under magnetically quiet circumstances the magnetic index eta indicates large magnetic disturbance, especially in vertical component when other magnetic indices inform about quiet magnetic conditions. The results indicate that the increase of the magnetic eta index (the ratio of the variations of vertical component of the external magnetic field to the horizontal component) is associated with the emergence of sporadic E layer or with increase of foEs critical frequency of sporadic E layer. The appearance of sporadic E layer followed 1-2 h after growth of magnetic index eta. An important conclusion is that the analysis of the hourly ionospheric data does not give 100% correlation between the increase of eta and the emergence of Es layer, however, studies of dense measurement data show that the correlation is almost 100%. An advantage of the eta index is the fact that after eliminating the effect of currents induced within the Earth, eta index bring independent and meaningful information on the system of current in the ionosphere. Hence, the eta index could be an important element of the ionosphere monitoring and can be used to predict such local phenomenon like the appearance of the sporadic E layer.

  5. Structural basis for the suppression of skin cancers by DNA polymerase [eta

    SciTech Connect

    Silverstein, Timothy D.; Johnson, Robert E.; Jain, Rinku; Prakash, Louise; Prakash, Satya; Aggarwal, Aneel K.

    2010-09-13

    DNA polymerase {eta} (Pol{eta}) is unique among eukaryotic polymerases in its proficient ability for error-free replication through ultraviolet-induced cyclobutane pyrimidine dimers, and inactivation of Pol{eta} (also known as POLH) in humans causes the variant form of xeroderma pigmentosum (XPV). We present the crystal structures of Saccharomyces cerevisiae Pol{eta} (also known as RAD30) in ternary complex with a cis-syn thymine-thymine (T-T) dimer and with undamaged DNA. The structures reveal that the ability of Pol{eta} to replicate efficiently through the ultraviolet-induced lesion derives from a simple and yet elegant mechanism, wherein the two Ts of the T-T dimer are accommodated in an active site cleft that is much more open than in other polymerases. We also show by structural, biochemical and genetic analysis that the two Ts are maintained in a stable configuration in the active site via interactions with Gln55, Arg73 and Met74. Together, these features define the basis for Pol{eta}'s action on ultraviolet-damaged DNA that is crucial in suppressing the mutagenic and carcinogenic consequences of sun exposure, thereby reducing the incidence of skin cancers in humans.

  6. New ruthenium carboxylate complexes having a 1-5-. eta. sup 5 -cyclooctadienyl ligand

    SciTech Connect

    Osakada, Kohtaro; Grohmann, A.; Yamamoto, Akio )

    1990-07-01

    Reaction of 3-butenoic acid with Ru(cod)(cot) (cod) = 1-2-{eta}{sup 2}:5-6-{eta}{sup 2}-cyclooctadiene; cot = 1-6-{eta}{sup 6}-cyclooctatriene in the presence of PMe{sub 3} gives a new ruthenium(II) complex formulated as Ru(1-5-{eta}{sup 5}-C{sub 8}H{sub 11}){eta}{sup 1}(O),{eta}{sup 2}(C,C{prime}-OCOCH{sub 2}CH{double bond}CH{sub 2})(PMe{sub 3}) (1). X-ray crystallography revealed its structure as having a piano-stool coordination around the ruthenium center. Crystals of 1 are tetragonal, space group P4{sub 3}2{sub 1}2, with a = 12.559 (3) {angstrom}, c = 20.455 (4) {angstrom}, and Z = 8. {sup 1}H and {sup 13}C({sup 1}H) NMR spectra of 1 agree well for the structure with the allyl entity of the carboxylate {pi}-bonded through the C{double bond}C double bond to ruthenium.

  7. Measurement of the gamma gamma* to eta_c transition form factor

    SciTech Connect

    Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; Hawkes, C.M.; /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2010-04-28

    The authors study the reaction e{sup +}e{sup -} {yields} e{sup +}e{sup -} {eta}{sub c}, {eta}{sub c} {yields} K{sub S}K{sup {+-}}{pi}{sup {-+}} and obtain {eta}{sub c} mass and width values 2982.2 {+-} 0.4 {+-} 1.6 MeV/c{sup 2} and 31.7 {+-} 1.2 {+-} 0.8 MeV, respectively. They find {Lambda}({eta}{sub c} {yields} {gamma}{gamma}){Beta}({eta}{sub c} {yields} K{bar K}{pi}) = 0.374 {+-} 0.009 {+-} 0.031 keV, and measure the {gamma}{gamma}* {yields} {eta}{sub c} transition form factor in the momentum transfer range from 2 to 50 GeV{sup 2}. The analysis is based on 469 fb{sup -1} of integrated luminosity collected at PEP-II with the BABAR detector at e{sup +}e{sup -} center-of-mass energies near 10.6 GeV.

  8. Precision Measurement of {eta} --> {gamma} {gamma} Decay Width via the Primakoff Effect

    SciTech Connect

    Gan, Liping Gin

    2013-08-01

    A precision measurement of the {eta} --> {gamma} {gamma} decay width via the Primakoff effect is underway in Hall D at Jefferson Lab. The decay width will be extracted from measured differential cross sections at forward angles on two light targets, liquid hydrogen and 4He, using a 11.5 GeV tagged photon beam. Results of this experiment will not only potentially resolve a long standing discrepancy between the Primakoff and the collider measurements, but will also reduce the experimental uncertainty by a factor of two on the average value of previous experimental results listed by the Particle Data Group(PDG). It will directly improve all other eta partial decay widths which rely on the accuracy of the eta radiative decay width. The projected 3% precision on the {Gamma}({eta} --> {gamma} {gamma} ) measurement will have a significant impact on the experimental determination of the fundamental parameters in QCD, such as the ratio of light quark masses (m{sub u},m{sub d},m{sub s}) and the {eta} - {eta}' mixing angle. It will be a sensitive probe for understanding QCD symmetries and the origin and the dynamics of QCD symmetry breaking.

  9. Eta Carinae and the Homunculus: an Astrophysical Laboratory

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Hartman, H.; Bautista, M. A.

    2012-05-01

    Today Eta Carinae, from the 1840s Great Eruption, is surrounded by a 20", neutral, dusty bipolar shell with intervening skirt, containing 12-40 solar masses of N-rich, C- and O-poor ejecta. The ionized Little Homunculus, ejected in the 1890s, expands within. At the core are a massive extended interacting wind structure and the bright Weigelt blobs, that change between a low-ionization (<7.8 eV) to a high-ionization state (>40 eV) driven by the 5.5-year massive binary. Thousands of narrow emission and absorption lines originate from a variety of regions: 1) the Weigelt blobs and the extended wind structures; 2) the Strontium Filament, a unique photoioionized metal nebula dominated by TiII, VII, SrII, ScII, CaII, MnII, CrII and FeI, but no HI; 3) the ionized Little Homunculus; and 4) the Homunculus seen in nearly a thousand atomic absorption lines in high and low states, but a thousand H2 absorptions only seen in the high state. Ionized iron-peak elements co-exist with CH, OH, NH and H2. This system is an excellent laboratory for the study of many iron-peak species from neutral to doubly-ionized states. The variations of incident radiation allow us to study atomic processes and derive atomic data not available from terrestrial laboratories, making Eta Carinae an astrophysical laboratory in its true sense. Moreover, the Homunculus, as inventoried by Herschel spectral scans, is dominated by N-bearing molecules. While C and O are depleted nearly 100-fold, due to CNO-nuclear reactions coupled with high conduction in the massive stellar cores, dust and molecules have still formed. How? Is the Homunculus dust metallic in character? Silicates and alumina? Could the formed dust also contribute to the C,O-depletions? Through multiple studies we are gaining clues on the robustness of molecular and dust formations.

  10. DOE Solar Energy Technologies Program TPP Final Report - A Value Chain Partnership to Accelerate U.S. PV Industry Growth, GE Global Research

    SciTech Connect

    Todd Tolliver; Danielle Merfeld; Charles Korman; James Rand; Tom McNulty; Neil Johnson; Dennis Coyle

    2009-07-31

    General Electric’s (GE) DOE Solar Energy Technologies TPP program encompassesd development in critical areas of the photovoltaic value chain that affected the LCOE for systems in the U.S. This was a complete view across the value chain, from materials to rooftops, to identify opportunities for cost reductions in order to realize the Department of Energy’s cost targets for 2010 and 2015. GE identified a number of strategic partners with proven leadership in their respective technology areas to accelerate along the path to commercialization. GE targeted both residential and commercial rooftop scale systems. To achieve these goals, General Electric and its partners investigated three photovoltaic pathways that included bifacial high-efficiency silicon cells and modules, low-cost multicrystalline silicon cells and modules and flexible thin film modules. In addition to these technologies, the balance of system for residential and commercial installations were also investigated. Innovative system installation strategies were pursed as an additional avenue for cost reduction.

  11. Accelerated Reader.

    ERIC Educational Resources Information Center

    Education Commission of the States, Denver, CO.

    This paper provides an overview of Accelerated Reader, a system of computerized testing and record-keeping that supplements the regular classroom reading program. Accelerated Reader's primary goal is to increase literature-based reading practice. The program offers a computer-aided reading comprehension and management program intended to motivate…

  12. Retrospective forecast of ETAS model with daily parameters estimate

    NASA Astrophysics Data System (ADS)

    Falcone, Giuseppe; Murru, Maura; Console, Rodolfo; Marzocchi, Warner; Zhuang, Jiancang

    2016-04-01

    We present a retrospective ETAS (Epidemic Type of Aftershock Sequence) model based on the daily updating of free parameters during the background, the learning and the test phase of a seismic sequence. The idea was born after the 2011 Tohoku-Oki earthquake. The CSEP (Collaboratory for the Study of Earthquake Predictability) Center in Japan provided an appropriate testing benchmark for the five 1-day submitted models. Of all the models, only one was able to successfully predict the number of events that really happened. This result was verified using both the real time and the revised catalogs. The main cause of the failure was in the underestimation of the forecasted events, due to model parameters maintained fixed during the test. Moreover, the absence in the learning catalog of an event similar to the magnitude of the mainshock (M9.0), which drastically changed the seismicity in the area, made the learning parameters not suitable to describe the real seismicity. As an example of this methodological development we show the evolution of the model parameters during the last two strong seismic sequences in Italy: the 2009 L'Aquila and the 2012 Reggio Emilia episodes. The achievement of the model with daily updated parameters is compared with that of same model where the parameters remain fixed during the test time.

  13. The Three-dimensional Structure of the Eta Carinae Homunculus

    NASA Technical Reports Server (NTRS)

    Steffen, W.; Teodoro, M.; Madura, T.I.; Groh, J.H.; Gull, T.R.; Mehner, A.; Corcoran, M.F.; Damineli, A.; Hamaguchi, K.

    2014-01-01

    We investigate, using the modeling code SHAPE, the three-dimensional structure of the bipolar Homunculus nebula surrounding Eta Carinae as mapped by new ESO VLT/X-Shooter observations of the H2 (lambda) = 2.12125 micrometers emission line. Our results reveal for the first time important deviations from the axisymmetric bipolar morphology: 1) circumpolar trenches in each lobe positioned point-symmetrically from the center and 2) offplanar protrusions in the equatorial region from each lobe at longitudinal (approximately 55 degrees) and latitudinal (10 degrees to 20 degrees) distances from the projected apastron direction of the binary orbit. The angular distance between the protrusions (approximately 110 degrees) is similar to the angular extent of each polar trench (approximately 130 degrees) and nearly equal to the opening angle of the wind-wind collision cavity (approximately 110 degrees). As in previous studies, we confirm a hole near the centre of each polar lobe and no detectable near-IR H2 emission from the thin optical skirt seen prominently in visible imagery. We conclude that the interaction between the outflows and/or radiation from the central binary stars and their orientation in space has had, and possibly still has, a strong influence on the Homunculus. This implies that prevailing theoretical models of the Homunculus are incomplete as most assume a single star origin that produces an axisymmetric nebula.We discuss how the newly found features might be related to the Homunculus ejection, the central binary and the interacting stellar winds.

  14. The -145 km/s Absorption System of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Vieira, G. L.; Gull, T. R.; Danks, A. C.; Johansson, S.

    2002-12-01

    With the STIS E230H mode (R 118,000), we have identified about twenty absorption components in line of sight from Eta Carinae. Two components, one at -513 km/s and another at -145 km/s, are quite different in character from the others, mostly at intermediate velocities (See adjacent posters by T. Gull and A. Danks). The -145 km/s component is significantly wider in fwhm, is seen in many more species, and the lower level can be above 20,000 cm-1, well above the 2000 cm-1 noted in the -513 km/s component. In the spectral region from 2400 to 3160A, approximately 500 absorption lines have been identified. In this poster, we will present line identifications and atomic parameters of the measured lines, hopefully providing insight as to what levels are being excited and by what processes. Observations were accomplished through STScI under proposal 9242 (Danks, P.I.). Funding is through the STIS GTO resources.

  15. Eta Carinae: At the Crossroads of becoming a Supernova

    NASA Technical Reports Server (NTRS)

    Gull, Theodore

    2007-01-01

    Since the 1840's, when Eta Carinae's visual magnitude rivaled Sirius, the brightest star in the night sky, astronomers have wondered what major event took place. Today with the Hubble Space Telescope Imaging Spectrograph, with CHANDRA X-ray spectroscopy and the Very Large Telescope spectrographs and interferometers, we have learned that over 12 solar masses of material was ejected at 500 to 700 km/s into interstellar space. This ejecta is quite different from the normal interstellar medium. It is rich in nitrogen, poor in oxygen and carbon. The dust properties are quite peculiar and many metals such as vanadium, strontium, cadmium are seen in both absorption against the central source, plus a number of molecules. The chemical and dust formation is likely dominated by nitrogen as we see H_2, CH, CH+, OH, NH, HCl and NH-3, but no CO. Other metals and molecules are being searched out in the FUSE, HST/STIS, VLT/UVES and VLT/CRIRES spectra. I will describe what we know about the massive binary stellar system, how it changes every 5.54 year in UV and X-ray output and how the massive ejecta responds in this astrophysical laboratory.

  16. Eta Carinae: an Update on the Integral Nebula

    NASA Astrophysics Data System (ADS)

    Gull, T. R.; Ishibashi, K.; Davidson, K.; Zethson, T.; Johannson, S.; Hartman, H.; Eta Carinae Cycle 7 and 8 Collaboration

    1999-12-01

    Observations of the ejecta associated with Eta Carinae were done using the Space Telescope Imaging Spectrograph (STIS) with CCD and grating settings yielding resolving power 5000 during four visits between December 1997 and February 1999. The identical position and position angle was utilized for the March 1998 and February 1999 observations that are continuous from 1640 to 10400A. In eleven months, considerable changes in nebular structure, nebular brightness, emission lines and absorption lines have taken place. Moreover, the nebular structures change rapidly on a scale of 0.1", the angular resolution of the STIS CCD. We have been systematically identifying both the emission lines and absorption lines present in the nebular spectrum. Multiple fluorescent lines are present and have changed considerably in intensity. Most notable is the change in iron ionization. Effectively the near ultraviolet transparency has increased due to conversion of much iron from Fe II to Fe III. This activity is funded by NASA through STIS GTO and STScI GO resources and through University of Lund, Sweden.

  17. CRITICAL DIFFERENCES AND CLUES IN ETA CAR'S 2009 EVENT ,

    SciTech Connect

    Mehner, Andrea; Davidson, Kris; Humphreys, Roberta M.; Martin, John C.; Ishibashi, Kazunori; Ferland, Gary J.

    2011-10-20

    We monitored Eta Carinae with the Hubble Space Telescope WFPC2 and Gemini GMOS throughout the 2009 spectroscopic event, which was expected to differ from its predecessor in 2003. Here we report major observed differences between events and their implications. Some of these results were quite unexpected. (1) The UV brightness minimum was much deeper in 2009. This suggests that physical conditions in the early stages of an event depend on different parameters than the 'normal' inter-event wind. Extra mass ejection from the primary star is one possible cause. (2) The expected He II {lambda}4687 brightness maximum was followed several weeks later by another. We explain why this fact and the timing of the {lambda}4687 maxima strongly support a 'shock breakup' hypothesis for X-ray and {lambda}4687 behavior as proposed 5-10 years ago. (3) We observed a polar view of the star via light reflected by dust in the Homunculus nebula. Surprisingly, at that location, the variations of emission-line brightness and Doppler velocities closely resembled a direct view of the star, which should not have been true for any phenomena related to the orbit. This result casts very serious doubt on all the proposed velocity interpretations that depend on the secondary star's orbital motion. (4) Latitude-dependent variations of H I, He I, and Fe II features reveal aspects of wind behavior during the event. In addition, we discuss implications of the observations for several crucial unsolved problems.

  18. UV photoemission studies of metal photocathodes for particle accelerators

    SciTech Connect

    Fischer, J.; Srinivasan-Rao, T.

    1988-09-01

    Photoemission from several metals was studied with 10 ps laser pulses at 266 nm. The yield was linear with energy and with area. Quantum efficiencies (/eta/) were determined (up to 10/sup /minus/3/ e/photons for samarium), and found to vary as (h..nu..-/phi/)/sup 2/. /eta/ also increased with the field. The field assisted efficiencies were calculated for some metals and confirmed by experiment for gold, up to surface fields of /approximately/3/times/10/sup 8/ V/m. High charge and current densities, close to 10/sup 5/ A/cm/sup 2/ from macroscopic areas, were measured or indicated. Results are then related to applications in accelerators. 18 refs., 15 figs., 4 tabs.

  19. LINEAR ACCELERATOR

    DOEpatents

    Colgate, S.A.

    1958-05-27

    An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.

  20. Recent Advances in Plasma Acceleration

    SciTech Connect

    Hogan, Mark

    2007-03-19

    The costs and the time scales of colliders intended to reach the energy frontier are such that it is important to explore new methods of accelerating particles to high energies. Plasma-based accelerators are particularly attractive because they are capable of producing accelerating fields that are orders of magnitude larger than those used in conventional colliders. In these accelerators a drive beam, either laser or particle, produces a plasma wave (wakefield) that accelerates charged particles. The ultimate utility of plasma accelerators will depend on sustaining ultra-high accelerating fields over a substantial length to achieve a significant energy gain. More than 42 GeV energy gain was achieved in an 85 cm long plasma wakefield accelerator driven by a 42 GeV electron drive beam in the Final Focus Test Beam (FFTB) Facility at SLAC. Most of the beam electrons lose energy to the plasma wave, but some electrons in the back of the same beam pulse are accelerated with a field of {approx}52 GV/m. This effectively doubles their energy, producing the energy gain of the 3 km long SLAC accelerator in less than a meter for a small fraction of the electrons in the injected bunch. Prospects for a drive-witness bunch configuration and high-gradient positron acceleration experiments planned for the SABER facility will be discussed.

  1. Muon Acceleration - RLA and FFAG

    SciTech Connect

    Bogacz, Alex

    2011-10-01

    Various acceleration schemes for muons are presented. The overall goal of the acceleration systems: large acceptance acceleration to 25 GeV and 'beam shaping' can be accomplished by various fixed field accelerators at different stages. They involve three superconducting linacs: a single pass linear Pre-accelerator followed by a pair of multi-pass Recirculating Linear Accelerators (RLA) and finally a non-scaling FFAG ring. The present baseline acceleration scenario has been optimized to take maximum advantage of appropriate acceleration scheme at a given stage. The solenoid based Pre-accelerator offers very large acceptance and facilitates correction of energy gain across the bunch and significant longitudinal compression trough induced synchrotron motion. However, far off-crest acceleration reduces the effective acceleration gradient and adds complexity through the requirement of individual RF phase control for each cavity. The RLAs offer very efficient usage of high gradient superconducting RF and ability to adjust path-length after each linac pass through individual return arcs with uniformly periodic FODO optics suitable for chromatic compensation of emittance dilution with sextupoles. However, they require spreaders/recombiners switchyards at both linac ends and significant total length of the arcs. The non-scaling Fixed Field Alternating Gradient (FFAG) ring combines compactness with very large chromatic acceptance (twice the injection energy) and it allows for large number of passes through the RF (at least eight, possibly as high as 15).

  2. Estimating Spatially Variable Parameters of the Epidemic Type Aftershock Sequence (ETAS) in California

    NASA Astrophysics Data System (ADS)

    Nandan, Shyam; Ouillon, Guy; Sornette, Didier; Wiemer, Stefan

    2016-04-01

    The ETAS model is widely employed to model the spatio-temporal distribution of earthquakes, generally using spatially invariant parameters, which is most likely a gross simplification considering the extremely heterogeneous structure of the Earth's crust. We propose an efficient method for the estimation of spatially varying parameters, using an expectation maximization (EM) algorithm and spatial Voronoi tessellations. We assume that each Voronoi cell is characterized by a set of eight constant ETAS parameters. For a given number of randomly distributed cells, Vi=1 to N, we jointly invert the ETAS parameters within each cell using an EM algorithm. This process is progressively repeated several times for a given N (which controls the complexity), which is itself increased incrementally. We use the Bayesian Information Criterion (BIC) to rank all the inverted models given their likelihood and complexity and select the top 1% models to compute the average model at any location. Using a synthetic catalog, we also check that the proposed method correctly inverts the known parameters. We apply the proposed method to earthquakes (M>=3) included in the ANSS catalog that occurred within the time period 1981-2016 in the spatial polygon defined by RELM/CSEP around California. The results indicate significant spatial variation of the ETAS parameters. Using these spatially variable estimates of ETAS parameters, we are better equipped to answer some important questions: (1) What is the seismic hazard (both long- and short-term) in a given region? (2) What kind of earthquakes dominate triggering? (3) are there regions where earthquakes are most likely preceded by foreshocks? Last but not the least, a possible correlation of the spatially varying ETAS parameters with spatially variable geophysical properties can lead to an improved understanding of the physics of earthquake triggering beside providing physical meaning to the parameters of the purely statistical ETAS model.

  3. Gluon and charm content of the {eta}{sup {prime}} meson and instantons

    SciTech Connect

    Shuryak, E.V. |; Zhitnitsky, A.R. |

    1998-02-01

    Motivated by recent CLEO measurements of the B{r_arrow}{eta}{sup {prime}}K decay, we evaluate the gluon and charm content of the {eta}{sup {prime}} meson using the interacting instanton liquid model of the QCD vacuum. Our main result is {l_angle}0{vert_bar}g{sup 3}f{sup abc}G{sub {mu}{nu}}{sup a}{tilde G}{sub {nu}{alpha}}{sup b}G{sub {alpha}{mu}}{sup c}{vert_bar}{eta}{sup {prime}}{r_angle}={minus}(2.3{endash}3.3) GeV{sup 2}{times}{l_angle}0{vert_bar}g{sup 2}G{sub {mu}{nu}}{sup a}{tilde G}{sub {mu}{nu}}{sup a}{vert_bar}{eta}{sup {prime}}{r_angle}. It is very large due to the strong field of small-size instantons. We show that it provides quantitative explanations of the CLEO data on the B{r_arrow}{eta}{sup {prime}}K decay rate (as well as the inclusive process B{r_arrow}{eta}{sup {prime}}+X), via a virtual Cabibbo-unsuppressed decay into a {bar c}c pair which then becomes {eta}{sup {prime}}. If so, a significant charm component may be present in other hadrons also: We briefly discuss the contribution of the charmed quark to the {ital polarized} deep-inelastic scattering on a proton. {copyright} {ital 1998} {ital The American Physical Society}

  4. Latitude-Dependent Effects in the Stellar Wind of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Smith, Nathan; Davidson, Kris; Gull, Theodore R.; Ishibashi, Kazunori; Hillier, D. John

    2002-01-01

    The Homunculus reflection nebula around eta Carinae provides the rare opportunity to observe the spectrum of a star from more than one direction. In the case of eta Car, the nebula's geometry is known well enough to infer how wind profiles vary with latitude. We present STIS spectra of several positions in the Homunculus, showing directly that eta Car has an aspherical and axisymmetric stellar wind. P Cygni absorption in Balmer lines depends on latitude, with relatively high velocities and strong absorption near the polar axis. Stronger absorption at high latitudes is surprising, and it suggests higher mass flux toward the poles, perhaps resulting from equatorial gravity darkening on a rotating star. Reflected profiles of He I lines are more puzzling, and offer clues to eta Car's wind geometry and ionization structure. During eta Car's high-excitation state in March 2000, the wind had a fast, dense polar wind, with higher ionization at low latitudes. Older STIS data obtained since 1998 reveal that this global stellar-wind geometry changes during eta Car's 5.5 year cycle, and may suggest that this star s spectroscopic events are shell ejections. Whether or not a companion star triggers these outbursts remains ambiguous. The most dramatic changes in the wind occur at low latitudes, while the dense polar wind remains relatively undisturbed during an event. The apparent stability of the polar wind also supports the inferred bipolar geometry. The wind geometry and its variability have critical implications for understanding the 5.5 year cycle and long-term variability, but do not provide a clear alternative to the binary hypothesis for generating eta Car s X-rays.

  5. Effect of Enzyme-Treated Asparagus Extract (ETAS) on Psychological Stress in Healthy Individuals.

    PubMed

    Takanari, Jun; Nakahigashi, Jun; Sato, Atsuya; Waki, Hideaki; Miyazaki, Shogo; Uebaba, Kazuo; Hisajima, Tatsuya

    2016-01-01

    The aim of this study was to examine the effectiveness of Enzyme-Treated Asparagus Extract (ETAS) on improving stress response. A randomized, double-blind, placebo-controlled cross-over trial was undertaken in healthy volunteers. ETAS (150 mg/d) or a placebo was consumed for 28 d, with a washout period. Psychological parameters were examined using a self-report scale questionnaire and psychological stress was applied using the Uchida-Kraepelin (U-K) test. During the stress load, autonomic nervous function was analyzed. After the stress load, a profile of mood states (POMS) psychological rating was performed, and serum cortisol, plasma catecholamine, salivary secretory immunoglobulin A (sIgA), and salivary cortisol were analyzed. ETAS intake improved the self-reported rating for the items "Feel tired," "Hard to get up," and "Feel heavy" in the psychological questionnaire; ameliorated the self-reported rating for the items "Depression-Dejection" and "Fatigue" in the POMS questionnaire; and increased salivary sIgA levels after the U-K test. In contrast, serum and salivary cortisol levels, and plasma catecholamine did not change. During the U-K test, ETAS significantly upregulated the sympathetic nerve activity. Furthermore, ETAS intake significantly increased the number of answers and the number of correct answers in the U-K test, suggesting that it might improve office work performance with swiftness and accuracy under stressful conditions. In conclusion, ETAS supplementation reduced feelings of dysphoria and fatigue, ameliorated quality of sleep, and enhanced stress-load performance as well as promoted stress response by increasing salivary sIgA levels. These data suggest ETAS intake may exert beneficial effects, resulting from well-controlled stress management, in healthy individuals. PMID:27465727

  6. The Persistent Eruption of UGC 2773-OT: finally, a decade-long extragalactic Eta Carinae analogue

    NASA Astrophysics Data System (ADS)

    Smith, Nathan; Andrews, Jennifer E.; Mauerhan, Jon C.; Zheng, WeiKang; Filippenko, Alexei V.; Graham, Melissa L.; Milne, Peter

    2016-02-01

    While supernova (SN) impostors resemble the Great Eruption of η Carinae in the sense that their spectra show narrow H lines and they have typical peak absolute magnitudes of -13 to -14 mag, most extragalactic events observed so far are quite different from η Car in duration. Their bright phases typically last for ˜100 d or less, rather than persisting for several years. The transient object UGC 2773-OT (discovered in 2009) had a similar peak absolute magnitude to other SN impostors, but with a gradual 5-yr pre-discovery rise. In the ˜6 yr since discovery, it has faded very slowly (0.26 mag yr-1). Overall, we suggest that its decade-long eruption is so far the best-known analogue of η Car's 19th century eruption. We discuss extensive spectroscopy of the ongoing eruption. The spectra show interesting changes in velocity and line shape that we discuss in detail, including an asymmetric Hα emission line that we show is consistent with the ejection of a bipolar nebula that could be very much like the Homunculus of η Car. Moreover, changes in the line width, line profile, blue excess emission resembling that of Type IIn SNe, and the intensity of Hα suggest the presence of strong circumstellar interaction in the eruption at late times. This supports the hypothesis that the extended plateau of η Car's eruption may have been powered by shock interaction as well. One interesting difference compared to η Car, however, is that UGC 2773-OT so far does not exhibit the repeated brief spikes in luminosity that have been associated with binary periastron events.

  7. Protein kinase C{eta} activates NF-{kappa}B in response to camptothecin-induced DNA damage

    SciTech Connect

    Raveh-Amit, Hadas; Hai, Naama; Rotem-Dai, Noa; Shahaf, Galit; Gopas, Jacob; Livneh, Etta

    2011-08-26

    Highlights: {yields} Protein kinase C-eta (PKC{eta}) is an upstream regulator of the NF-{kappa}B signaling pathway. {yields} PKC{eta} activates NF-{kappa}B in non-stressed conditions and in response to DNA damage. {yields} PKC{eta} regulates NF-{kappa}B by activating I{kappa}B kinase (IKK) and inducing I{kappa}B degradation. -- Abstract: The nuclear factor {kappa}B (NF-{kappa}B) family of transcription factors participates in the regulation of genes involved in innate- and adaptive-immune responses, cell death and inflammation. The involvement of the Protein kinase C (PKC) family in the regulation of NF-{kappa}B in inflammation and immune-related signaling has been extensively studied. However, not much is known on the role of PKC in NF-{kappa}B regulation in response to DNA damage. Here we demonstrate for the first time that PKC-eta (PKC{eta}) regulates NF-{kappa}B upstream signaling by activating the I{kappa}B kinase (IKK) and the degradation of I{kappa}B. Furthermore, PKC{eta} enhances the nuclear translocation and transactivation of NF-{kappa}B under non-stressed conditions and in response to the anticancer drug camptothecin. We and others have previously shown that PKC{eta} confers protection against DNA damage-induced apoptosis. Our present study suggests that PKC{eta} is involved in NF-{kappa}B signaling leading to drug resistance.

  8. Development of a partnership with government and industry to accelerate the commercialization of hydrogen. Final report, 9/30/1995--10/31/1996

    SciTech Connect

    1996-12-31

    This Final Technical Report provides a summary of the activities performed by the NHA in accordance with the Cooperative Agreement. Activities are broken down by task area, and include the following: (1) Information exchange within the NHA, which includes the two NHA newsletters, the NHA Advocate, and the H{sub 2} Digest, as well as directory information. (2) Information exchange within the hydrogen industry, which includes conferences and meeting attendance, presentations of papers, and HTAP activities. (3) Information exchange with other critical industries and the public, which includes press conferences, and public awareness activities. (4) Annual US hydrogen meeting, NHA`s signature event. The 7th Annual US Hydrogen Meeting was held April 2--4, 1996 in Alexandria, Virginia in conjunction with the US DOE`s Hydrogen Technical Advisory Panel Meeting and the SAE`s Fuel Cell TOPTEC. (5) Industry perspective and needs, which covers activities related to the Hydrogen Industrialization Plan. (6) Codes and standards, which includes workshop and workgroup activities, as well as other safety-related activities. The objective of the codes and standards activities is to establish expert working groups to develop industry consensus on safety issues, and develop compatible standards and formats, and product certification protocols.

  9. Development of a partnership with government and industry to accelerate the commercialization of hydrogen. Final report, November 1, 1996--October 31, 1997

    SciTech Connect

    1998-09-01

    The National Hydrogen Association (NHA) was born out of a Hydrogen Workshop, November 16 and 17, 1988, held at the Electric Power Research Institute in Palo Alto, California. The following mission statement was adopted and remains the statement of the organization: to foster the development of hydrogen technologies and their utilization in industrial and commercial applications and to promote the transition role of hydrogen in the energy field. This final technical report provides a summary of the activities performed by the NHA. Activities are broken down by task area, and include the following: Information exchange within the NHA; Information exchange within the hydrogen industry; Information exchange with other critical industries and the public; Annual US hydrogen meeting; Codes and standards which includes establishing industry consensus on safety issues; Industry perspective and needs; and Administrative. Appendices to this report include the following: Role of the NHA in strategic planning for the hydrogen economy--An international initiative; Hydrogen safety report; and Implementation plan workshop II, whose purpose was to seek commercialization scenarios and strategies to introduce hydrogen in near-term transportation and power markets.

  10. Observation of eta_c(1S) and eta_c(2S) decays to K K-pi pi-pi0 in two-photon interactions

    SciTech Connect

    Sanchez, P.del Amo

    2011-05-20

    We study the processes {gamma}{gamma} {yields} K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} and {gamma}{gamma} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0} using a data sample of 519.2 fb{sup -1} recorded by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at center-of-mass energies near the {Upsilon}(nS) (n = 2, 3, 4) resonances. We observe the {eta}{sub c}(1S), {chi}{sub c0}(1P), {chi}{sub c2}(1P), and {eta}{sub c}(2S) resonances produced in two-photon interactions and decaying to K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup 0}, with significances of 18.1, 5.7, 5.2, and 5.3 standard deviations (including systematic errors), respectively. We measure the {eta}{sub c}(2S) mass and width in K{sub S}{sup 0}K{sup {+-}}{pi}{sup {-+}} decays, m({eta}{sub c}(2S)) = 3638.5 {+-} 1.5 {+-} 0.8 MeV/c{sup 2} and {Lambda}({eta}{sub c}(2S)) = 13.4 {+-} 4.6 {+-} 3.2 MeV, where the first uncertainty is statistical and the second is systematic. We search for the Z(3930) resonance and find no significant signal. We also provide the two-photon width times branching fraction values for the observed resonances.

  11. Acceleration switch

    DOEpatents

    Abbin, J.P. Jr.; Devaney, H.F.; Hake, L.W.

    1979-08-29

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  12. Acceleration switch

    DOEpatents

    Abbin, Jr., Joseph P.; Devaney, Howard F.; Hake, Lewis W.

    1982-08-17

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  13. ION ACCELERATOR

    DOEpatents

    Bell, J.S.

    1959-09-15

    An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

  14. LINEAR ACCELERATOR

    DOEpatents

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  15. The sub-arcsecond dusty environment of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Chesneau, O.; Min, M.; Herbst, T.; Waters, L. B. F. M.; Hillier, D. J.; Leinert, Ch.; de Koter, A.; Pascucci, I.; Jaffe, W.; Köhler, R.; Alvarez, C.; van Boekel, R.; Brandner, W.; Graser, U.; Lagrange, A. M.; Lenzen, R.; Morel, S.; Schöller, M.

    2005-06-01

    The core of the nebula surrounding Eta Carinae has been observed with the VLT Adaptive Optics system NACO and with the interferometer VLTI/MIDI to constrain spatially and spectrally the warm dusty environment and the central object. In particular, narrow-band images at 3.74 μm and 4.05 μm reveal the butterfly shaped dusty environment close to the central star with unprecedented spatial resolution. A void whose radius corresponds to the expected sublimation radius has been discovered around the central source. Fringes have been obtained in the Mid-IR which reveal a correlated flux of about 100 Jy situated 0.3 arcsec south-east of the photocenter of the nebula at 8.7 μm, which corresponds with the location of the star as seen in other wavelengths. This correlated flux is partly attributed to the central object, and these observations provide an upper limit for the SED of the central source from 2.2 μm to 13.5 μm. Moreover, we have been able to spectrally disperse the signal from the nebula itself at PA = 318 degree, i.e. in the direction of the bipolar nebula (~310°) within the MIDI field of view of 3 arcsec. A large amount of corundum (Al2O3) is discovered, peaking at 0.6 arcsec-1.2 arcsec south-east from the star, whereas the dust content of the Weigelt blobs is dominated by silicates. We discuss the mechanisms of dust formation which are closely related to the geometry of this Butterfly nebulae.

  16. The Strontium Filament within the Homunculus of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Hartman, H.; Zethson, T.; Johansson, S.; Ishibashi, K.; Davidson, K.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    During a series of HST/STIS observations of Eta Carinae and associated ejecta, we noticed a peculiar emission filament located a few arcseconds north of the central source. While bright in nebular standards, it is submerged in a sea of scattered starlight until moderately high dispersion, long-slit spectroscopy with the STIS (R- 8000) brings the emission lines out. The initial spectrum, centered on 6768A with the STIS G750M grating, led to identification of twenty lines from singly-Ionized species including [Sr II], [Fe II], [Ti II], [Ni II], [Mn II], and [Co II] (Zethson, etal., 2001, AJ 122,322). No Balmer emission is detected from this filament and the Fe II 2507,9 lines, known to be pumped by Lyman alpha radiation in other regions near the central source, are not detected. Followup observations have led to detection of hundreds more emission lines from iron group elements in neutral and singly-ionized states. Thus far all are excited by less than 10 eV. This peculiar nebular emission is thought to be due to very intense stellar radiation, stripped of uv flux shortward of Lyman alpha, bathing a neutral structure. We are systematically identifying the many lines (over 90% identified) and measuring line intensities that will then be modeled to determine excitation mechanisms, temperature and density. Two [Sr II] and two Sr II lines have now been measured. Bautista, etal. (in preparation) have modeled the strontium flux ratios and find that large radiation fluxes and/or high strontium abundances may account for the detected emission. These observations were supported by STIS GTO funding and GO funding through the STScI

  17. Eta Carinae and the Homunculus: An Astrophysical Laboratory

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.

    2006-01-01

    High spatial resolution spectroscopy with HST/STIS between 1998.0 and 2004.2 has provided much exciting information about the central binary system and the physics of its N-rich, C,O-poor ejecta. Stellar He I profiles, noticeably blue-shifted relative to P Cygni H and Fe II line profiles, originate from the ionized wind region between two massive companions. Changes in profiles of He I singlet and triplet lines provide clues to the excitation mechanisms involved as the hot, UV companion moves in its highly eccentric orbit. For 90% of the 5.54-year period, the spectra of nearby Weigelt blobs and the Little Homunculus include highly excited emission lines of Ar, Ne, and Fe. During the few month-long spectroscopic minimum, these systems are deprived of Lyman continuum. Recombination, plus cooling, occurs. In the skirt region between the bipolar Homunculus, a neutral emission region, devoid of hydrogen emission, glows in Ti II, Fe I, Sr II, Sc II, etc. We find the ejecta to have Ti/Ni abundances nearly 100 times solar, not due to nuclear processing, but due to lack of oxygen. Many metals normally tied up in interstellar dust remain in gaseous phase. Much information is being obtained on the physical processes in these warm N-rich gases, whose excitation varies with time in a predictable pattern. Indeed recent GRB high dispersion spectra include signatures of circumGRB warm gases. This indicates that the early, primordial massive stars have warm massive ejecta reminiscent to that around Eta Carinae.

  18. Eta Carinae and the Homunculus: an Astrophysical Laboratory

    NASA Astrophysics Data System (ADS)

    Gull, T. R.

    2007-08-01

    High spatial resolution spectroscopy with HST/STIS between 1998.0 and 2004.2 has provided much exciting information about the central binary system and the physics of its N-rich, C,O-poor ejecta. Stellar He I profiles, noticeably blue-shifted relative to P Cygni H and Fe II line profiles, originate from the ionized wind region between two massive companions. Changes in profiles of He I singlet and triplet lines provide clues to the excitation mechanisms involved as the hot, UV companion moves in its highly eccentric orbit. For 90% of the 5.54-year period, the spectra of nearby Weigelt blobs and the Little Homunculus include highly excited emission lines of Ar, Ne, and Fe. During the few month-long spectroscopic minimum, these systems are deprived of Lyman continuum. Recombination, plus cooling, occurs. In the skirt region between the bipolar Homunculus, a neutral emission region, devoid of hydrogen emission, glows in Ti II, Fe I, Sr II, Sc II, etc. We find the ejecta to have Ti/Ni abundances nearly 100 times solar, not due to nuclear processing, but due to lack of oxygen. Many metals normally tied up in interstellar dust remain in gaseous phase. Much information is being obtained on the physical processes in these warm N-rich gases, whose excitation varies with time in a predictable pattern. Indeed recent GRB high dispersion spectra include signatures of circumGRB warm gases. This indicates that the early, primordial massive stars have warm massive ejecta reminiscent to that around Eta Carinae.

  19. Critical Differences and Clues in Eta Car's 2009 Event

    NASA Astrophysics Data System (ADS)

    Mehner, Andrea; Davidson, Kris; Martin, John C.; Humphreys, Roberta M.; Ishibashi, Kazunori; Ferland, Gary J.

    2011-10-01

    We monitored Eta Carinae with the Hubble Space Telescope WFPC2 and Gemini GMOS throughout the 2009 spectroscopic event, which was expected to differ from its predecessor in 2003. Here we report major observed differences between events and their implications. Some of these results were quite unexpected. (1) The UV brightness minimum was much deeper in 2009. This suggests that physical conditions in the early stages of an event depend on different parameters than the "normal" inter-event wind. Extra mass ejection from the primary star is one possible cause. (2) The expected He II λ4687 brightness maximum was followed several weeks later by another. We explain why this fact and the timing of the λ4687 maxima strongly support a "shock breakup" hypothesis for X-ray and λ4687 behavior as proposed 5-10 years ago. (3) We observed a polar view of the star via light reflected by dust in the Homunculus nebula. Surprisingly, at that location, the variations of emission-line brightness and Doppler velocities closely resembled a direct view of the star, which should not have been true for any phenomena related to the orbit. This result casts very serious doubt on all the proposed velocity interpretations that depend on the secondary star's orbital motion. (4) Latitude-dependent variations of H I, He I, and Fe II features reveal aspects of wind behavior during the event. In addition, we discuss implications of the observations for several crucial unsolved problems. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership. Based on observations made with the NASA/ESA Hubble Space Telescope. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under the NASA contract NAS 5-26555.

  20. The three-dimensional structure of the Eta Carinae Homunculus

    NASA Astrophysics Data System (ADS)

    Steffen, W.; Teodoro, M.; Madura, T. I.; Groh, J. H.; Gull, T. R.; Mehner, A.; Corcoran, M. F.; Damineli, A.; Hamaguchi, K.

    2014-08-01

    We investigate, using the modelling code SHAPE, the three-dimensional structure of the bipolar Homunculus nebula surrounding Eta Carinae as mapped by new ESO Very Large Telescope/X-Shooter observations of the H2 λ = 2.121 25 μm emission line. Our results reveal for the first time important deviations from the axisymmetric bipolar morphology: (1) circumpolar trenches in each lobe positioned point symmetrically from the centre and (2) off-planar protrusions in the equatorial region from each lobe at longitudinal (˜55°) and latitudinal (10°-20°) distances from the projected apastron direction of the binary orbit. The angular distance between the protrusions (˜110°) is similar to the angular extent of each polar trench (˜130°) and nearly equal to the opening angle of the wind-wind collision cavity (˜110°). As in previous studies, we confirm a hole near the centre of each polar lobe and no detectable near-IR H2 emission from the thin optical skirt seen prominently in visible imagery. We conclude that the interaction between the outflows and/or radiation from the central binary stars and their orientation in space has had, and possibly still has, a strong influence on the Homunculus. This implies that prevailing theoretical models of the Homunculus are incomplete as most assume a single-star origin that produces an axisymmetric nebula. We discuss how the newly found features might be related to the Homunculus ejection, the central binary, and the interacting stellar winds.

  1. Accelerator simulation of astrophysical processes

    NASA Technical Reports Server (NTRS)

    Tombrello, T. A.

    1983-01-01

    Phenomena that involve accelerated ions in stellar processes that can be simulated with laboratory accelerators are described. Stellar evolutionary phases, such as the CNO cycle, have been partially explored with accelerators, up to the consumption of He by alpha particle radiative capture reactions. Further experimentation is indicated on reactions featuring N-13(p,gamma)O-14, O-15(alpha, gamma)Ne-19, and O-14(alpha,p)F-17. Accelerated beams interacting with thin foils produce reaction products that permit a determination of possible elemental abundances in stellar objects. Additionally, isotopic ratios observed in chondrites can be duplicated with accelerator beam interactions and thus constraints can be set on the conditions producing the meteorites. Data from isotopic fractionation from sputtering, i.e., blasting surface atoms from a material using a low energy ion beam, leads to possible models for processes occurring in supernova explosions. Finally, molecules can be synthesized with accelerators and compared with spectroscopic observations of stellar winds.

  2. International Aspects of Particle Accelerators

    NASA Astrophysics Data System (ADS)

    Sessler, Andrew

    2013-04-01

    The development of particle accelerators -- an activity that started about 1930 and is still on-going -- is very much an international activity. There have been international contributions to this development all along the way. The result is remarkably effective accelerators, for many different activities, spread throughout the world. Because many don't appreciate this story and, furthermore, that it is very much worthy of explicit recognition, this session and this talk have been organized. In the talk, a survey will be made of the start of accelerators: electrostatic machines, cyclotrons, betatrons, linacs, synchrotrons, and colliders. Then a brief survey will be given of the more important contributions to particle accelerators. For each of these concepts we shall discuss the physics behind the concept, the origin of the concept, and the places where development and implementation took place. Some of the various applications of accelerators will then be presented. Finally we shall show, in broad terms, the present distribution of particle accelerators.

  3. DNA damage targets PKC{eta} to the nuclear membrane via its C1b domain

    SciTech Connect

    Tamarkin, Ana; Zurgil, Udi; Braiman, Alex; Hai, Naama; Krasnitsky, Ella; Maissel, Adva; Ben-Ari, Assaf; Yankelovich, Liat; Livneh, Etta

    2011-06-10

    Translocation to cellular membranes is one of the hallmarks of PKC activation, occurring as a result of the generation of lipid secondary messengers in target membrane compartments. The activation-induced translocation of PKCs and binding to membranes is largely directed by their regulatory domains. We have previously reported that PKC{eta}, a member of the novel subfamily and an epithelial specific isoform, is localized at the cytoplasm and ER/Golgi and is translocated to the plasma membrane and the nuclear envelope upon short-term activation by PMA. Here we show that PKC{eta} is shuttling between the cytoplasm and the nucleus and that upon etoposide induced DNA damage is tethered at the nuclear envelope. Although PKC{eta} expression and its phosphorylation on the hydrophobic motif (Ser675) are increased by etoposide, this phosphorylation is not required for its accumulation at the nuclear envelope. Moreover, we demonstrate that the C1b domain is sufficient for translocation to the nuclear envelope. We further show that, similar to full-length PKC{eta}, the C1b domain could also confer protection against etoposide-induced cell death. Our studies demonstrate translocation of PKC{eta} to the nuclear envelope, and suggest that its spatial regulation could be important for its cellular functions including effects on cell death.

  4. Eta Car: The Good, the Bad and the Ugly of Nebular and Stellar Confusion

    NASA Technical Reports Server (NTRS)

    Gull, T.R.; Sonneborn, G.; Jensen, A.G.; Nielsen, K.E.; Vieira Kover, G.; Hillier, D.J.

    2008-01-01

    Observations in the far-UV provide a unique opportunity to investigate the very massive star Eta Car and its hot binary companion, Eta Car B. Eta Car was observed with FUSE over a large portion of the 5.54 year spectroscopic period before and after the 2003.5 minimum. The observed spectrum is defined by strong stellar wind signatures, primarily from Eta Car A, complicated by the strong absorptions of the ejecta surrounding Eta Car plus interstellar absorption. The Homunculus and Little Homunculus are massive bipolar ejecta historically associable with LBV outbursts in the 1840s and the 1890s and are linked to absorptions at -513 and -146 km/s, respectively. The FUSE spectra are confused by the extended nebulosity and thermal drifting of the FUSE co-pointed instruments. Interpretation is further complicated by two B-stars sufficiently close to h Car to be included most of the time in the large FUSE aperture. Followup observations partially succeeded in obtaining spectra of at least one of these B-stars through the smaller apertures, allowing potential separation of the B-star contributions and h Car. A complete analysis of all available spectra is currently underway. Our ultimate goals are to directly detect the hot secondary star if possible with FUSE and to identify the absorption contributions to the overall spectrum especially of the stellar members and the massive ejecta.

  5. The DARHT Scattering Wire Spectrometer: Operation and Checkout on ETA II

    SciTech Connect

    Fessenden, T J

    2005-03-09

    The DARHT Scattering wire energy spectrometer has been realized and checked out on ETA II. The ETA II beam energy is generally around 5.3 MeV. This value varies from pulse-to-pulse by around 0.5% and from month-to-month by as much as 6%. The energy acceptance of the spectrometer is {+-} 5% and the time response is less than 10 ns. The instrument was calibrated to enable absolute measurements of the ETA II beam energy accurate to {+-}3%. The beam energy in MeV is related to the bending magnetic field B{sub kG} according to E{sub MeV} = 0.511[{radical}(1+347.2B{sub kG}{sup 2}) -1]. The major difficulty encountered was in the development of detectors for the scattered electrons passing through the instrument. Fortunately one detector was fabricated that worked satisfactorily which enabled us to complete the tests on ETA II. The ETA II experiments and initial FXR experiments suggest that spurious X-ray signals will not prove troublesome. No results are yet available in the x-ray environment of DARHT.

  6. Episodic post-shock dust formation in the colliding winds of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Smith, Nathan

    2010-02-01

    Eta Carinae shows broad peaks in near-infrared (IR) JHKL photometry, roughly correlated with times of periastron passage in the eccentric binary system. After correcting for secular changes attributed to reduced extinction from the thinning Homunculus nebula, these peaks have IR spectral energy distributions (SEDs) consistent with emission from hot dust at 1400-1700 K. The excess SEDs are clearly inconsistent, however, with the excess being entirely due to free-free wind or photospheric emission. One must conclude, therefore, that the broad near-IR peaks associated with Eta Carinae's 5.5yr variability are due to thermal emission from hot dust. I propose that this transient hot dust results from episodic formation of grains within compressed post-shock zones of the colliding winds, analogous to the episodic dust formation in Wolf-Rayet (WR) binary systems like WR 140 or the post-shock dust formation seen in some supernovae like SN 2006jc. This dust formation in Eta Carinae seems to occur preferentially near and after periastron passage; near-IR excess emission then fades as the new dust disperses and cools. With the high grain temperatures and Eta Car's C-poor abundances, the grains are probably composed of corundum or similar species that condense at high temperatures, rather than silicates or graphite. Episodic dust formation in Eta Car's colliding winds significantly impacts our understanding of the system, and several observable consequences are discussed.

  7. Swift Observations of the Recent X-ray Activity of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Kalil Liburd, Jamar; Corcoran, Michael F.; Morris, David C.; Theodore Gull, Kenji Hamaguchi, Thomas Madura, Mairan Teodoro, Nick Durofchalk, Caleb Gimar.

    2015-01-01

    The extremely massive Luminous Blue Variable binary star, Eta Carinae, lies 7,500 light years away, deep within the Homunculus nebula where vigorous Wind-Wind collisions between the primary star and the companion star generate high-energy gases that produce X-rays. Complex X-ray variations occur near periastron, the point of least stellar separation between the two stars. Understanding the variability in Eta Carinae's high-energy spectrum during this period gives us a better understanding of the system's physical and stellar properties. We present the processing techniques and background estimation methods used to process and analyze weekly observations done with Swift's X-ray Telescope during Eta Carinae's most recent periastron passage in 2014. We present analysis of Eta Carinae's current column density and compare it to that of previous cycles. The exact nature of Eta Carinae's X-ray minimum activity, which occurs every 5.54 years, is still unclear. A detailed understanding of the mechanisms of the X-ray deep minimum stage and the associated differences in column density in each cycle will contribute to a clearer understanding of the wind-driven mass-loss from this unique system.

  8. Study of {pi}{sup -}p{yields}{pi}{sup -{eta}p} and {pi}{sup -}p{yields}{pi}{sup -{eta}{eta}}p at {radical}(s) = 18.9 GeV with the COMPASS experiment

    SciTech Connect

    Uman, I.; Schlueter, T.

    2010-08-05

    The COMPASS experiment at CERN studies diffractively produced states in the light quark sector with unprecedented statistics. The observation of f{sub 0}(1500)/f{sub 2}'(1525) decaying to {eta}{eta} in 2008 data with incoming negative pion beam at 190 GeV/c poses the question whether it is produced centrally or formed by the decay of a heavier diffractively produced {pi}{sub 1}(1800)/{pi}{sub 2}(1880). To decide, a dedicated amplitude analysis which includes different production mechanisms is formulated and compared with one which was used to fit centrally produced resonances including f{sub 0}(1500) by the WA102 experiment. Unbinned mass-dependent log-likelihood fitting methods may serve to solve the ambiguities which are present in binned, mass-independent partial wave analyses.

  9. Stereospecific alkylations of molybdenum(II) enolates from eta/sup 2/-aceyl complexes

    SciTech Connect

    Rusik, C.A.; Templeton, J.L.

    1986-07-23

    The authors report here spectroscopic characterization and alkylation and aldol reactions of these Mo(II) enolate complexes as well as the structure of one diastereomer of (Tp')Mo(CO)(P(OPh)/sub 3/)(C(O)CHMEBz), Tp' = hydridotris(3,5-dimethylpyrazolyl)borate). Aldol condensation reactions of transition-metal enolates have not been reported as frequently as alkylation reactions. The authors find that metal enolate reacts with benzaldehyde to yield a deep indigo eta/sup 2/-enone derivative resulting from dehydration of the initial ..beta..-hydroxy eta/sup 2/-acyl product. The formation of (Tp')CO)/sub 2/Mo(eta/sup 2/-C(O)CMe = CHPh) (9) suggests that a range of electrophiles will react with these molybdenum(II) enolate reagents.

  10. Evidence for the decay tau/sup -/. -->. pi. /sup -/eta nu/sub tau/

    SciTech Connect

    Repond, J.

    1987-01-01

    The inclusive production of eta mesons in tau lepton decay has been studied using the High Resolution Spectrometer at the PEP e/sup +/e/sup -/ facility. The data sample corresponds to an integrated luminosity of 300 pb/sup -1/ and the storage ring was operated at ..sqrt..s = 29 GeV. The eta production appears to be only compatible with the decay tau/sup -/ ..-->.. ..pi../sup -/eta nu, which violates isospin and G-parity conservation. The branching ratio of 5.1 +- 1.5% explains much of the current discrepancy between the one-prong topological branching ratio and the sum of the individual one-prong modes. Various checks to test the validity of the signal are described.

  11. Brighter Still! A Summary of Photometric Data from the HST Eta Carinae Treasury Project

    NASA Astrophysics Data System (ADS)

    Martin, John C.; Davidson, K.; Koppelman, M. D.; Humphreys, R. M.

    2006-12-01

    During the past decade Eta Carinae has brightened markedly, indicating a possible change of state. Here we summarize the photometry of just the central star including STIS/CCD and ACS/HRC data gathered for the HST Eta Carinae Treasury project. The current eight-year brightening trend is reminiscent of 1938--1953 when the 5.5 year spectroscopic cycle first appeared. Already the brightness of the central star has begun to overwhelm the bright inner ejecta. Our results indicate that its mass loss rate is probably decreasing. Over the coming decades this should cause the ionization of the Little Homunculus and other envelopes of ejecta, dramatically altering the appearance of Eta Car.

  12. Circumventing the eta problem in building an inflationary model in string theory

    SciTech Connect

    Easson, Damien A.; Gregory, Ruth

    2009-10-15

    The eta problem is one of the most significant obstacles to building a successful inflationary model in string theory. Planck mass suppressed corrections to the inflaton potential generally lead to inflaton masses of order the Hubble scale and generate contributions of order unity to the {eta} slow-roll parameter rendering prolonged slow-roll inflation impossible. We demonstrate the severity of this problem in the context of brane antibrane inflation in a warped throat of a Calabi-Yau flux compactification with all phenomenologically dangerous moduli stabilized. Using numerical solutions we show that the eta problem can be avoided in scenarios where the inflaton is nonminimally coupled to gravity and has Dirac-Born-Infeld kinetic term. We show that the resulting cosmic microwave background observables such as measures of non-Gaussianites can, in principle, serve as a probe of scalar-gravity couplings.

  13. The Spatially-resolved Interacting Winds of Eta Carinae: Implications on the Orbit Orientation

    NASA Technical Reports Server (NTRS)

    Gull, Theodore R.; Nielsen, K.E.; Corcoran, M.; Hamaguchi, K.; Madura, T.; Russell, C.; Hillier, D.J.; Owocki. S.; Okazaki, A.T.

    2010-01-01

    Medium-dispersion long slit spectra, recorded by HST/STIS (R=8000, Theta=0.l"), resolve the extended wind-wind interaction region of the massive binary, Eta Carinae. During the high state, extending for about five years of the 5.54-year binary period, lines of [N II], [Fe III], [S III], [Ar III] and [Ne III] extend outwards to 0.4" with a velocity range of -500 to +200 km/s. By comparison, lines of [Fe II] and [Ni II] extend to 0.7" with a velocity range of -500 to +500 km/s. During the high state, driven by the lesser wind of Eta Car B and photo-ionized by the FUV of Eta Car B, the high excitation lines originate in or near the outer ballistic portions of the wind-wind interaction region. The lower excitation lines ([Fe II] and [Ni II D originate from the boundary regions of the dominating wind of Eta Car A. As the binary system has an eccentricity exceeding 0.9, the two stars approach quite close across the periastron, estimated to be within 1 to 2 AU. As a result, Eta Car B moves into the primary wind structure, cutting off the FUV supporting the ionization of the high state lines. Forbidden emission lines of the doubly-ionized species disappear, He II 4686 drops along with the collapse of the X-ray flux. This behavior is understood through the 3-D models of A. Okazaki and of E. R. Parkin and Pittard. Discussion will address the orbit orientation relative to the geometry of the Homunculus, ejected by Eta Carinae in the 1840s.

  14. NUV Spectroscopic Studies of Eta Car's Weigelt D across the 2003.5 Minimum

    NASA Technical Reports Server (NTRS)

    Ivarsson, S.; Nielsen, K. E.; Gull, T. R.; Hillier, J. D.

    2006-01-01

    HST/STIS high dispersion, high spatial resolution spectra in the near UV (2424-2705A) were recorded of Weigelt D, located 0.25" from Eta Carinae, before, during and after the star's 2003.5 minimum. Most nebular emission, including Lyman-alpha pumped Fe II and [Fe III] lines show phase dependent variations with disappearance at the minimum and reappearance a few months later. Circumstellar absorptions increase at minimum, especially in the Fe II resonance lines originating not only from ground levels but also meta stable levels well above the ground levels. These ionization/excitation effects can be explained by a sudden change in UV flux reaching the blobs, likely due to a line-of-sight obscuration of the hotter companion star, Eta Car B, recently discovered by Iping et al. (poster, this meeting). The scattered starlight seen towards Weigelt D display noticeable different line profiles than the direct starlight from Eta Carinae. P-Cygni absorption profiles in Fe II stellar lines observed directly towards Eta Carinae, show terminal velocities up to -550 km/s. However, scattered starlight of Weigelt D display significant lower velocities ranging from -40 to -150 km/s.We interpret this result to be indicative that no absorbing Fe II wind structure exists between the Central source and Weigelt D. The lower velocity absorption appears to be connected to the outer Fe II wind structure of Eta Car A extending beyond Weigelt D intersecting the observer's line of sight. This result is consistent with the highly extended wind of Eta Car A.

  15. Distinct ETA receptor binding mode of macitentan as determined by site directed mutagenesis.

    PubMed

    Gatfield, John; Mueller Grandjean, Celia; Bur, Daniel; Bolli, Martin H; Nayler, Oliver

    2014-01-01

    The competitive endothelin receptor antagonists (ERA) bosentan and ambrisentan, which have long been approved for the treatment of pulmonary arterial hypertension, are characterized by very short (1 min) occupancy half-lives at the ET(A) receptor. The novel ERA macitentan, displays a 20-fold increased receptor occupancy half-life, causing insurmountable antagonism of ET-1-induced signaling in pulmonary arterial smooth muscle cells. We show here that the slow ET(A) receptor dissociation rate of macitentan was shared with a set of structural analogs, whereas compounds structurally related to bosentan displayed fast dissociation kinetics. NMR analysis showed that macitentan adopts a compact structure in aqueous solution and molecular modeling suggests that this conformation tightly fits into a well-defined ET(A) receptor binding pocket. In contrast the structurally different and negatively charged bosentan-type molecules only partially filled this pocket and expanded into an extended endothelin binding site. To further investigate these different ET(A) receptor-antagonist interaction modes, we performed functional studies using ET(A) receptor variants harboring amino acid point mutations in the presumed ERA interaction site. Three ET(A) receptor residues significantly and differentially affected ERA activity: Mutation R326Q did not affect the antagonist activity of macitentan, however the potencies of bosentan and ambrisentan were significantly reduced; mutation L322A rendered macitentan less potent, whereas bosentan and ambrisentan were unaffected; mutation I355A significantly reduced bosentan potency, but not ambrisentan and macitentan potencies. This suggests that--in contrast to bosentan and ambrisentan--macitentan-ET(A) receptor binding is not dependent on strong charge-charge interactions, but depends predominantly on hydrophobic interactions. This different binding mode could be the reason for macitentan's sustained target occupancy and insurmountable

  16. The Spatially-resolved Interacting Winds of Eta Carinae: Implications on the Orbit Orientation

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Nielsen, K. E.; Corcoran, M.; Hamaguchi, K.; Madura, T.; Russell, C.; Hillier, D. J.; Owocki, S.; Okazaki, A. T.

    2010-01-01

    Medium-dispersion long slit spectra, recorded by HST/STIS (R=8000, Theta=0.1"), resolve the extended wind-wind interaction region of the massive binary, Eta Carinae. During the high state, extending for about five years of the 5.54-year binary period, lines of [N II], [Fe III], [S III], [Ar III] and [Ne III] extend outwards to 0.4" with a velocity range of -500 to +200 km/s. By comparison, lines of [Fe II] and [Ni II] extend to 0.7" with a velocity range of -500 to +500 km/s. During the high state, driven by the lesser wind of Eta Car B and photo-ionized by the FUV of Eta Car B, the high excitation lines originate in or near the outer ballistic portions of the wind-wind interaction region. The lower excitation lines ([Fe II] and [Ni II]) originate from the boundary regions of the dominating wind of Eta Car A. As the binary system has an eccentricity exceeding 0.9, the two stars approach quite close across the periastron, estimated to be within 1 to 2 AU. As a result, Eta Car B moves into the primary wind structure, cutting off the FUV supporting the ionization of the high state lines. Forbidden emission lines of the doubly-ionized species disappear, He II 4686 drops along with the collapse of the X-ray flux. This behavior is understood through the 3-D models of A. Okazaki and of E. R. Parkin and Pittard. Discussion will address the orbit orientation relative to the geometry of the Homunculus, ejected by Eta Carinae in the 1840s.

  17. Acceleration Studies

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.

    1993-01-01

    Work to support the NASA MSFC Acceleration Characterization and Analysis Project (ACAP) was performed. Four tasks (analysis development, analysis research, analysis documentation, and acceleration analysis) were addressed by parallel projects. Work concentrated on preparation for and implementation of near real-time SAMS data analysis during the USMP-1 mission. User support documents and case specific software documentation and tutorials were developed. Information and results were presented to microgravity users. ACAP computer facilities need to be fully implemented and networked, data resources must be cataloged and accessible, future microgravity missions must be coordinated, and continued Orbiter characterization is necessary.

  18. Molecules and Dust in the Humunculus: Ejecta of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, T.

    2007-01-01

    In the 18401s, Eta Carinae ejected massive amounts of nitrogen-rich, carbon- and oxygen-poor material which we see as the hourglass-shaped Homunculus. With the Hubble Space Telescope Imaging Spectrograph, we detected multiple shells in line of sight, the most massive and intriguing being at -513 km/s. Numerous lines of Fe I, Fe II, Ni II, Cr II, Sc II, Sr II, Ti II, V II, etc are identified as well as nearly a thousand H2 lines. The metals have energy level populations consistent with 760K and excited by photons < 8.5eV. We have now identified CH, CH+, OH, and NH at the same velocity, but at 60K, suggesting stratification in the outer ejecta. Analysis of the interior, photoionized emission hourglass structure, known as the Little Homunculus, indicates He, N overabundances and C, 0 underabundances (approximately 1/80 solar). A skirt of neutral and partially ionized gas lies between the lobes of the hourglasses. A portion is seen as the Strontium Filament, a metal- ionized, neutral hydrogen structure. Relative abundances of TiNi are 1/80 solar, CrNi are 1/20 solar. This complex of ejecta appears to have been ejected by a massive star(s) at the end of the hydrogen-burning phase when convection led to overproduction of nitrogen at the expense of carbon and oxygen. Given the underabundances of carbon and oxygen, the chemistry of this system is quite different to the normal ISM, leading to a nitrogen- dominated chemistry. What little C and 0 that is formed is immediately taken up by SiO and Al0 molecules leading to a very different gas/dust ratio than the normal ISM. Dust in this ejecta is abundance, but known to be very grey in character. Observations with HST/STIS and VLT/UVES will be presented along with simple physical models and CLOUD modeling. Insight by the participants will be solicited.

  19. The sub-arcsecond dusty environment of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Chesneau, O.; Min, M.; Herbst, T.; Waters, L. B. F. M.; Leinert, Ch.; Hillier, D. J.

    2005-09-01

    The core of the nebula surrounding Eta Carinae was observed with the VLT Adaptive Optics system NACO and with the interferometer VLTI/MIDI to spatially and spectrally isolate the warm dusty environment and the central object. Narrow-band images at 3.74 μm and 4.05 μm reveal a butterfly shaped dusty environment close to the central star with unprecedented spatial resolution. Fringes have been obtained in the Mid-IR and a correlated flux of about 100 Jy situated 0.3 arcsec south-east from the photocenter of the nebula at 8.7 μm is detected. This flux is partly attributed to the central object and provides an upper limit for the SED of the central source from 3.8 μm to 13.5 μm. We have been able to spectrally disperse the signal from the nebula itself at PA=318 degree, i.e. in the direction of the bipolar nebula (˜310°) within the MIDI field of view of 3 arcsec. A large amount of corundum (Al2O3) is discovered, peaking at 0.6-1.2 arcsec south-east from the star, whereas the dust content of the Weigelt blobs, in the equatorial plane, is dominated by silicates. We propose a geometry for the Butterfly nebulae assuming a similar axis for the large and little Homunculus. We suggest that the Butterfly nebulae is a consequence of the 1890 outburst and is embedded in the Little Homonculus its geometry is, mostly shaped by the local dust formation conditions which are directly affected by the latitudinal dependance of the ejection and the present wind. The dust is mostly formed in the bright rims of the Butterfly nebula. The dust condenses closer to the poles of the star owing to the larger mass-loss rate and the relative velocity between the stellar wind and the ejecta at these latitudes. In this geometry, the bright southern clump directly sees the southern pole of the central object. At intermediate latitudes, the mass-loss rate and the relative velocity of the wind are decreased and dust forms further out. We suggest that the survival and the large mass of the

  20. The ``Ghost Shell'': Discovery of the Forward Shock from Colliding Winds about Eta Carinae

    NASA Astrophysics Data System (ADS)

    Dorland, B. N.; Currie, D. G.; Kaufer, A.; Bacciotti, F.

    2003-01-01

    We report on the newly discovered ``Ghost Shell'' around eta Carinae. We have detected a high-velocity ( ~ - 850 km /s), spatially extended, narrow emission feature lying in front of the southeast lobe of eta Carinae's homunculus. This feature has the speed of a high-velocity shock but the spectrum of a low-velocity shock. We propose that the Ghost Shell is the forward shock between the fast stellar wind of the great eruption of 1842 and the older, slow, massive wind. This discovery is described in more detail in Currie, Dorland, & Kaufer (2002).

  1. SPIN ASYMMETRIES A(ET) AND A(T) IN EXCLUSIVE ETA ELECTROPRODUCTION FROM THE PROTON

    SciTech Connect

    P.E. Bosted

    2004-10-10

    For the first time, measurements were made of the double-spin asymmetry A_et and the target single-spin asymmetry A_t in the exclusive reaction p(e,e'p)eta in kinematics dominated by the excitation of the S_11 (1535) resonance. Both A_et and A_t are found to be in agreement with the Eta-MAID model, which predicts strong dominance of S_11 (1535) excitation in the region studied, 0.3 < Q^2 < 1 GeV^2 and 1.49 < W < 1.59 GeV.

  2. Search for bound states of the eta-meson in light nuclei

    NASA Technical Reports Server (NTRS)

    Chrien, R. E.; Bart, S.; Pile, P.; Sutter, R.; Tsoupas, N.; Funsten, H. O.; Finn, J. M.; Lyndon, C.; Punjabi, V.; Perdrisat, C. F.

    1988-01-01

    A search for nuclear-bound states of the eta meson was carried out. Targets of lithium, carbon, oxygen, and aluminum were placed in a pion(+) beam at 800 MeV/c. A predicted eta bound state in O-15* (E sub x approx. = 540 MeV) with a width of approx. 9 MeV was not observed. A bound state of a size 1/3 of the predicted cross section would have been seen in this experiment at a confidence level of 3sigma (P is greater than 0.9987).

  3. Preliminary results for the helicity asymmetry E for eta photoproduction on the proton

    SciTech Connect

    B. T. Morrison, M. Dugger, B. G. Ritchie, CLAS Collaboration

    2012-04-01

    Polarization observables are an important tool for clarifying the nucleon resonance spectrum. No previous measurements for double polarization asymmetries have been published for eta photoproduction. Double polarization measurements have been made at Jefferson Lab using a polarized photon beam and protons in a polarized frozen spin target (FROST). Data were taken during the first running period of FROST using the CLAS detector with photon energies from 0.33 to 2.35 GeV. Preliminary results for the E polarization observable for eta meson photoproduction from the proton at threshold and above, along with comparisons to several theoretical predictions are presented.

  4. Mapping and Modeling the Extended Winds of the Massive Interacting Binary, Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, Ted

    2010-01-01

    The combination HST/STIS high spatial and moderate spectral resolutions have revealed the massive interacting wind structure of Eta Carinae by forbidden lines of singly and doubly ionized elements. Throughout the 5.54-year period, lines of Fe++, Ne++, Ar++, S++ and N+ reveal the interacting wind structures, near critical electron densities of 10(exp 5) to 3 x 10(exp 7)cu cm, photoionized by the hot secondary, Eta Car B, Lines of Fe+ and Ni+ trace the denser (>10(exp 7)cu cm. less-ionized (< 8 eV) primary wind of Eta Car A as it wraps around the interacting binary stars. For 5 years of the 5.54 year period, the FUV radiation from Eta Car B escapes the orbital region, ionizing the boundaries of the expanding wind structures. But for three to six months, Eta Car B plunges into the primary wind approaching to within 1 to 2 AU, leading to cutoff of FUV and X-ray fluxes. The interacting wind structure, resolved out to 0.8", drops io ionization and then rebuilds as Eta Car B emerges from the primary wind envelope. Solid Particle Hydrodynamical(SPH) models have been developed extending out to 2000 AU and adapted to include FUV radiation effects of the winds. In turn, synthetic spectroimages of selected forbidden lines have been constructed and compared to the spectroimages recorded by the HST/STIS throughout 1998.0 to 2004.3, extending across the 1998 and 2003.5 minima. By this method, we show that the orbital axis of the binary system must bc within 15 degrees of the Homunculus axis of symmetry and that periastron occurs with Eta Car B passing on the far side of Eta Car B. This result ties the current binary orbit with the bipolar ejection with intervening skirt and leads to implications that the binary system influenced the mass ejection of the l840s and the lesser ejection of the 1890s.

  5. An Aboriginal Australian Record of the Great Eruption of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Hamacher, Duane W.; Frew, David J.

    2010-11-01

    We present evidence that the Boorong Aboriginal people of northwestern Victoria observed the Great Eruption of Eta Carinae in the nineteenth century and incorporated this event into their oral traditions. We identify this star, as well as others not specifically identified by name, using descriptive material presented in the 1858 paper by William Edward Stanbridge in conjunction with early southern star catalogues. This identification of a transient astronomical event supports the assertion that Aboriginal oral traditions are dynamic and evolving, and not static. This is the only definitive indigenous record of Eta Carinae's outburst identified in the literature to date.

  6. Measurement of the B -> Omega l Nu and B -> Eta l Nu Branching Fractions Using Neutrino Reconstruction

    SciTech Connect

    Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, Vincent; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, Antimo; Pappagallo, M.; Eigen, G.; Stugu, Bjarne; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, Robert N.; Jacobsen, R.G.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /Consorzio Milano Ricerche /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Napoli Seconda U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /INFN, Pisa /Princeton U. /Banca di Roma /Frascati /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2008-09-09

    The authors present a study of the charmless semileptonic B-meson decays B{sup +} {yields} {omega}{ell}{sup +}{nu} and B{sup +} {yields} {eta}{ell}{sup +}{nu}. The analysis is based on 383 million B{bar B} pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector. The {omega} mesons are reconstructed in the channel {omega} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} and the {eta} mesons in the channels {eta} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} and {eta} {yields} {gamma}{gamma}. They measure the branching fractions {Beta}(B{sup +} {yields} {omega}{ell}{sup +}{nu}) = (1.14 {+-} 0.16{sub stat} {+-} 0.08{sub syst}) x 10{sup -4} and {Beta}(B{sup +} {yields} {eta}{ell}{sup +}{nu}) = (0.31 {+-} 0.06{sub stat} {+-} 0.08{sub syst}) x 10{sup -4}.

  7. Enzyme-treated Asparagus officinalis extract shows neuroprotective effects and attenuates cognitive impairment in senescence-accelerated mice.

    PubMed

    Sakurai, Takuya; Ito, Tomohiro; Wakame, Koji; Kitadate, Kentaro; Arai, Takashi; Ogasawara, Junetsu; Kizaki, Takako; Sato, Shogo; Ishibashi, Yoshinaga; Fujiwara, Tomonori; Akagawa, Kimio; Ishida, Hitoshi; Ohno, Hideki

    2014-01-01

    Increases in the number of patients with dementia involving Alzheimer's disease (AD) are seen as a grave public health problem. In neurodegenerative disorders involving AD, biological stresses, such as oxidative and inflammatory stress, induce neural cell damage. Asparagus (Asparagus officinalis) is a popular vegetable, and an extract prepared from this reportedly possesses various beneficial biological activities. In the present study, we investigated the effects of enzyme-treated asparagus extract (ETAS) on neuronal cells and early cognitive impairment of senescence-accelerated mouse prone 8 (SAMP8) mice. The expression of mRNAs for factors that exert cytoprotective and anti-apoptotic functions, such as heat-shock protein 70 and heme oxygenase-1, was upregulated in NG108-15 neuronal cells by treatment with ETAS. Moreover, when release of lactate dehydrogenase from damaged NG108-15 cells was increased for cells cultured in medium containing either the nitric oxide donor sodium nitroprusside or the hypoxia mimic reagent cobalt chloride, ETAS significantly attenuated this cell damage. Also, when contextual fear memory, which is considered to be a hippocampus-dependent memory, was significantly impaired in SAMP8 mice, ETAS attenuated the cognitive impairment. These results suggest that ETAS produces cytoprotective effects in neuronal cells and attenuates the effects on the cognitive impairment of SAMP8 mice. PMID:24660475

  8. Plasma accelerator

    DOEpatents

    Wang, Zhehui; Barnes, Cris W.

    2002-01-01

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  9. Accelerated Achievement

    ERIC Educational Resources Information Center

    Ford, William J.

    2010-01-01

    This article focuses on the accelerated associate degree program at Ivy Tech Community College (Indiana) in which low-income students will receive an associate degree in one year. The three-year pilot program is funded by a $2.3 million grant from the Lumina Foundation for Education in Indianapolis and a $270,000 grant from the Indiana Commission…

  10. ACCELERATION INTEGRATOR

    DOEpatents

    Pope, K.E.

    1958-01-01

    This patent relates to an improved acceleration integrator and more particularly to apparatus of this nature which is gyrostabilized. The device may be used to sense the attainment by an airborne vehicle of a predetermined velocitv or distance along a given vector path. In its broad aspects, the acceleration integrator utilizes a magnetized element rotatable driven by a synchronous motor and having a cylin drical flux gap and a restrained eddy- current drag cap deposed to move into the gap. The angular velocity imparted to the rotatable cap shaft is transmitted in a positive manner to the magnetized element through a servo feedback loop. The resultant angular velocity of tae cap is proportional to the acceleration of the housing in this manner and means may be used to measure the velocity and operate switches at a pre-set magnitude. To make the above-described dcvice sensitive to acceleration in only one direction the magnetized element forms the spinning inertia element of a free gyroscope, and the outer housing functions as a gimbal of a gyroscope.

  11. Particle acceleration

    NASA Technical Reports Server (NTRS)

    Vlahos, L.; Machado, M. E.; Ramaty, R.; Murphy, R. J.; Alissandrakis, C.; Bai, T.; Batchelor, D.; Benz, A. O.; Chupp, E.; Ellison, D.

    1986-01-01

    Data is compiled from Solar Maximum Mission and Hinothori satellites, particle detectors in several satellites, ground based instruments, and balloon flights in order to answer fundamental questions relating to: (1) the requirements for the coronal magnetic field structure in the vicinity of the energization source; (2) the height (above the photosphere) of the energization source; (3) the time of energization; (4) transistion between coronal heating and flares; (5) evidence for purely thermal, purely nonthermal and hybrid type flares; (6) the time characteristics of the energization source; (7) whether every flare accelerates protons; (8) the location of the interaction site of the ions and relativistic electrons; (9) the energy spectra for ions and relativistic electrons; (10) the relationship between particles at the Sun and interplanetary space; (11) evidence for more than one acceleration mechanism; (12) whether there is single mechanism that will accelerate particles to all energies and also heat the plasma; and (13) how fast the existing mechanisms accelerate electrons up to several MeV and ions to 1 GeV.

  12. Measurements of B to {pi, eta, eta'} l nu Branching Fractions andDetermination of |Vub| with Semileptonically Tagged B Mesons

    SciTech Connect

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Cahn, R.N.; Jacobsen, R.G.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U., EKP /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /Frascati /Frascati /Rome U. /Frascati /Frascati /Rome U. /Frascati /Frascati /Rome U. /Frascati /Frascati /Rome U. /Frascati /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2008-06-02

    The authors report measurements of branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup -}, {pi}{sup 0}, {eta} and {eta}{prime}, based on 348 fb{sup -1} of data collected with the BABAR detector, using B{sup 0} and B{sup +} mesons found in the recoil of a second B meson decaying as B {yields} D{sup (*)}{ell}{nu}{sub {ell}}. Assuming isospin symmetry, they combine pionic branching fractions to obtain {Beta}(B{sup 0} {yields} {pi}{sup -} {ell}{sup +} {nu}{sub {ell}}) = (1.54 {+-} 0.17{sub (stat)} {+-} 0.09{sub (syst)}) x 10{sup -4}; they find 3.2{sigma} evidence of the decay B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}} and measure its branching fraction to be (0.64 {+-} 0.20{sub (stat)} {+-} 0.3{sub (syst)}) x 10{sup -4}, and determine {Beta}(B{sup +} {yields} {eta}{prime}{ell}{sup +}{nu}{sub {ell}}) < 0.47 x 10{sup -4} to 90% confidence level. Using partial branching fractions for the pionic decays in ranges of the momentum transfer and a recent form factor calculation, they obtain the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}| = (4.0 {+-} 0.5{sub (stat)} {+-} 0.2{sub (syst){sub -0.5}{sup +0.7}(theory)}) x 10{sup -3}.

  13. Branching ratios and CP asymmetries of B{yields}K{eta}{sup (')} decays in the perturbative QCD approach

    SciTech Connect

    Xiao Zhenjun; Zhang Zhiqing; Liu Xin; Guo Libo

    2008-12-01

    We calculate the branching ratios and CP-violating asymmetries of the four B{yields}K{eta}{sup (')} decays in the perturbative QCD (pQCD) factorization approach. Besides the full leading-order contributions, the partial next-to-leading-order (NLO) contributions from the QCD vertex corrections, the quark-loops, and the chromomagnetic penguins are also taken into account. The NLO pQCD predictions for the CP-averaged branching ratios are Br(B{sup +}{yields}K{sup +}{eta}){approx_equal}3.2x10{sup -6}, Br(B{sup {+-}}{yields}K{sup {+-}}{eta}{sup '}){approx_equal}51.0x10{sup -6}, Br(B{sup 0}{yields}K{sup 0}{eta}){approx_equal}2.1x10{sup -6}, and Br(B{sup 0}{yields}K{sup 0}{eta}{sup '}){approx_equal}50.3x10{sup -6}. The NLO contributions can provide a 70% enhancement to the LO Br(B{yields}K{eta}{sup '}), but a 30% reduction to the LO Br(B{yields}K{eta}), which play the key role in understanding the observed pattern of branching ratios. The NLO pQCD predictions for the CP-violating asymmetries, such as A{sub CP}{sup dir}(K{sub S}{sup 0}{eta}{sup '}){approx}2.3% and A{sub CP}{sup mix}(K{sub S}{sup 0}{eta}{sup '}){approx}63%, agree very well with currently available data. This means that the deviation {delta}S=A{sub CP}{sup mix}(K{sub S}{sup 0}{eta}{sup '})-sin2{beta} in pQCD approach is also very small.

  14. Measurements of B --> {pi,eta,eta;{'}}lnu_{l} branching fractions and determination of |V_{ub}| with semileptonically tagged B mesons.

    PubMed

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Cahn, R N; Jacobsen, R G; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Teodorescu, L; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Wilson, M G; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Smith, J G; Ulmer, K A; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Mader, W F; Nogowski, R; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Klose, V; Lacker, H M; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Bard, D J; Dauncey, P D; Nash, J A; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Firmino da Costa, J; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; George, K A; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Alwyn, K E; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Hertzbach, S S; Li, X; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Wang, W F; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Del Amo Sanchez, P; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Biesiada, J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Roethel, W; Wilson, F F; Emery, S; Escalier, M; Esteve, L; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Pierini, M; Prepost, R; Vuosalo, C O; Wu, S L

    2008-08-22

    We report measurements of branching fractions for the decays B-->Plnu_{l}, where P are the pseudoscalar charmless mesons pi;{-}, pi;{0}, eta and eta;{'}, based on 348 fb;{-1} of data collected with the BABAR detector, using B0 and B+ mesons found in the recoil of a second B meson decaying as B-->D;{(*)}lnu_{l}. Assuming isospin symmetry, we combine pionic branching fractions to obtain B(B;{0}-->pi;{-}l;{+}nu_{l})=(1.54+/-0.17_{(stat)}+/-0.09_{(syst)})x10;{-4}; we find 3.2sigma evidence of the decay B;{+}-->etal;{+}nu_{l} and measure its branching fraction to be (0.64+/-0.20_{(stat)}+/-0.03_{(syst)})x10;{-4}, and determine B(B;{+}-->eta;{'}l;{+}nu_{l})<0.47x10;{-4} to 90% confidence level. Using partial branching fractions for the pionic decays in ranges of the momentum transfer and a variety of form factor calculation, we obtain values of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}| in ranging from 3.6x10;{-3} to 4.1x10;{-3}. PMID:18764602

  15. 3D Radiative Transfer in Eta Carinae: The SimpleX Radiative Transfer Algorithm Applied to 3D SPH Simulations of Eta Car's Colliding Winds

    NASA Astrophysics Data System (ADS)

    Clementel, N.; Madura, T. I.; Kruip, C. J. H.; Icke, V.; Gull, T. R.

    2014-04-01

    At the heart of the spectacular bipolar Homunculus nebula lies an extremely luminous (5*10^6 L_sun) colliding wind binary with a highly eccentric (e ~ 0.9), 5.54-year orbit and a total mass ~ 110 M_sun. Our closest (D ~ 2.3 kpc) and best example of a pre-hypernova environment, Eta Carinae is an ideal astrophysical laboratory for studying massive binary interactions, stellar wind-wind collisions, and massive star evolution. In order to improve our knowledge of the system, we need to generate synthetic observations and compare them with the already available and future HST/STIS data. We present initial results from full 3D radiative transfer post-processing of 3D SPH hydrodynamical simulations of the interacting winds of Eta Carinae. We use SimpleX algorithm to obtain the ionization fractions of hydrogen and helium, this results in ionization maps of both species that constrain the regions where these lines can form. These results will allow us to put constraints on the number of ionizing photons coming from the companion. This construction of synthetic observations allows us to obtain insight into the highly complex 3D flows in Eta, from the shape of the ionized volume and its resulting optical/spectral appearance.

  16. The ISAC post-accelerator

    NASA Astrophysics Data System (ADS)

    Laxdal, R. E.; Marchetto, M.

    2014-01-01

    The acceleration chain of the ISAC facility boosts the energy of both radioactive and stable light and heavy ions for beam delivery to both a medium energy area in ISAC-I and a high energy area in ISAC-II. The post-accelerator comprises a 35.4 MHz RFQ to accelerate beams of A/q ≤ 30 from 2 keV/u to 150 keV/u and a post stripper, 106.1 MHz variable energy drift tube linac (DTL) to accelerate ions of A/q ≤ 6 to a final energy between 0.15 MeV/u to 1.5 MeV/u. A 40 MV superconducting linac further accelerates beam from 1.5 MeV/u to energies above the Coulomb barrier. All linacs operate cw to preserve beam intensity.

  17. Compact accelerator

    DOEpatents

    Caporaso, George J.; Sampayan, Stephen E.; Kirbie, Hugh C.

    2007-02-06

    A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

  18. Evaluation of the 29-km Eta Model for Weather Support to the United States Space Program

    NASA Technical Reports Server (NTRS)

    Manobianco, John; Nutter, Paul

    1997-01-01

    The Applied Meteorology Unit (AMU) conducted a year-long evaluation of NCEP's 29-km mesoscale Eta (meso-eta) weather prediction model in order to identify added value to forecast operations in support of the United States space program. The evaluation was stratified over warm and cool seasons and considered both objective and subjective verification methodologies. Objective verification results generally indicate that meso-eta model point forecasts at selected stations exhibit minimal error growth in terms of RMS errors and are reasonably unbiased. Conversely, results from the subjective verification demonstrate that model forecasts of developing weather events such as thunderstorms, sea breezes, and cold fronts, are not always as accurate as implied by the seasonal error statistics. Sea-breeze case studies reveal that the model generates a dynamically-consistent thermally direct circulation over the Florida peninsula, although at a larger scale than observed. Thunderstorm verification reveals that the meso-eta model is capable of predicting areas of organized convection, particularly during the late afternoon hours but is not capable of forecasting individual thunderstorms. Verification of cold fronts during the cool season reveals that the model is capable of forecasting a majority of cold frontal passages through east central Florida to within +1-h of observed frontal passage.

  19. Eta(') mass and chiral symmetry breaking at large N(c) and N(f).

    PubMed

    Girlanda, L; Stern, J; Talavera, P

    2001-06-25

    We propose a method for implementing the large- N(c), large-N(f) limit of QCD at the effective Lagrangian level. Depending on the value of the ratio N(f)/N(c), different patterns of chiral symmetry breaking can arise, leading in particular to different behaviors of the eta(') mass in the combined large-N limit. PMID:11415379

  20. 78 FR 48463 - Comment Request for Information Collection for Form ETA 9033, Attestation by Employers Using...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-08

    ..., Attestation by Employers Using Alien Crewmembers for Longshore Activities in U.S. Ports and Form ETA 9033-A, Attestation by Employers Using Alien Crewmembers for Longshore Activities in the State of Alaska; Extension... Attestation by Employers Using Alien Crewmembers for Longshore Activities in U.S. Ports (OMB Control...

  1. APPLICATION OF BIAS AND ADJUSTMENT TECHNIQUES TO THE ETA-CMAQ AIR QUALITY FORECAST

    EPA Science Inventory

    The current air quality forecast system, based on linking NOAA's Eta meteorological model with EPA's Community Multiscale Air Quality (CMAQ) model, consistently overpredicts surface ozone concentrations, but simulates its day-to-day variability quite well. The ability of bias cor...

  2. Improving solar radiation forecasts from Eta/CPTEC model using statistical post-processing

    NASA Astrophysics Data System (ADS)

    Guarnieri, R. A.; Pereira, E. B.; Chou, S. C.

    Solar radiation forecasts are mainly demanded by the energy sector besides other applications Accurate short-term forecasts of solar energy resources are required for management of co-generation systems and energy dispatch in transmission lines Mesoscale weather forecast models usually have radiation parameterization codes since solar radiation is the main energy source for atmospheric processes The Eta model running operationally in the Brazilian Center of Weather Forecast and Climate Studies CPTEC INPE is a mesoscale model with 40 km horizontal resolution This model has outputs for many meteorological variables including solar radiation incidence on ground These radiation forecasts are nevertheless greatly overestimated As an attempt to improve the forecasts of solar energy resources using Eta model statistical post-processing models or refining models were used Multiple linear regression MLR models were adjusted and artificial neural networks ANN were trained using a statistically selected group of 7 variables predicted by the Eta model not including the Eta solar radiation forecast itself This group of variables expresses the future weather and surface conditions Theoretical solar radiation amount on the top of atmosphere TOA was calculated and used as another input Solar radiation measurements from piranometers Kipp Zonen CM-21 installed on two ground-stations of the SONDA Project were used as the targets to be simulated throughout the adjustment training of the models These measurements were also used

  3. 20 CFR 658.420 - Establishment of JS complaint system at the ETA regional office.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (RDEOSR) and, where appropriate, handled in accordance with procedures at 29 CFR part 31. (2) The handling... 20 Employees' Benefits 4 2014-04-01 2014-04-01 false Establishment of JS complaint system at the ETA regional office. 658.420 Section 658.420 Employees' Benefits EMPLOYMENT AND...

  4. The X-ray Lightcurve of Eta Carinae, 1996-2014

    NASA Astrophysics Data System (ADS)

    Corcoran, Michael F.; Hamaguchi, Kenji; Liburd, Jamar; Gull, Theodore R.; Madura, Thomas; Teodoro, Mairan; Moffat, Anthony F. J.; Richardson, Noel; Russell, Christopher Michael Post; Pollock, A.; Owocki, Stanley P.

    2015-01-01

    Eta Carinae is the nearest example of a supermassive, superluminous, unstable star. Mass loss from the system is important in shaping its circumstellar medium and in determining the ultimate fate of the star. Eta Car loses mass via a dense, slow stellar wind and possesses one of the largest mass loss rates known. It is prone to episodes of extreme mass ejection via eruptions from some as-yet unspecified cause; the best examples of this are the large-scale eruptions which occurred in the mid-19th century, and then again about 50 years later. Eta Car is a colliding wind binary in which strong variations in X-ray emission and in other wavebands are driven by the violent collision of the wind of Eta Car and the fast, less dense wind of an otherwise hidden companion star. X-ray variations are the simplest diagnostic we have to study the wind-wind collision and allow us to measure the state of the stellar mass loss from both stars. We present the X-ray lightcurve over the last 20 years from monitoring observations with the Rossi X-ray Timing Explorer and the X-ray Telescope on the Swift satellite, and compare and contrast the behavior of the X-ray emission from the system over that timespan, including surprising variations during the 2014 X-ray minimum.

  5. The stability of the He II 4686 line emission across periastron passages in eta Carinae

    NASA Astrophysics Data System (ADS)

    Teodoro, Mairan; Heathcote, Bernard; Richardson, Noel; Prates, Rodrigo; Damineli, Augusto; Hickel, Gabriel; Bohlsen, Terry; Luckas, Paul; Locke, Malcolm; Navarete, Felipe; West, Julian; Andrade, Thiago A.; Coimbra, Adriano M.; Fernandez-Lajus, Eduardo; Gull, Theodore; Jablonski, Francisco; Corcoran, Michael F.; Groh, Jose H.; Hamaguchi, Kenji; Madura, Thomas; St-Jean, Lucas; Weigelt, Gerd

    2014-08-01

    Preliminary analysis of data from the international campaign to monitor eta Carinae through the 2014 event shows that, as expected, the equivalent width of the He II 4686 emission line has reached its minimum strength on JD=2456870.8 (August 01 2014).

  6. Photometric monitoring of eta Carinae, and the general problem of accurate photometry of S Dor variables

    NASA Astrophysics Data System (ADS)

    Sterken, C.; Freyhammer, L. M.; Arentoft, T.; van Genderen, A. M.

    2001-06-01

    We review the particular problems of ground-based photometry of the composite object eta Carinae for which high-precision long-term photometric monitoring is so hard to accomplish. eta Car, by its appearance as an ultrabright extended object, by its anomalous spectral nature, and by its most outspoken variability, is the single most difficult stellar object to measure photometrically and to monitor over a long time interval. The problems belong to several levels: very limited availability of an astrophysically appropriate photometric system, the presence of strong (and variable) emission lines, the need for a telescope with a suitable f-ratio, and the steadily diminishing possibilities to collect data over a long period of time. We demonstrate that the transformation from our y measurements to V is valid for many stars, but not for eta Car nor for some less peculiar objects. Even pure Johnson V data can not be guaranteed to be accurately tied to the E-region standard stars. The'underestimated' V-magnitude of eta Car based on y-filter photometry is not to be considered a suspicious characteristic of our intermediate-band photometry, but is an inherent element of the photometric approach of discussing V magnitudes on the basis of data obtained with a Stromgren y filter. Aperture corrections of a single isolated measurement remain prone to random errors of the order of 0.005-0.015 mag.

  7. 31 CFR Appendix A to Part 208 - Model Disclosure for Use Until ETA SM Becomes Available

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Model Disclosure for Use Until ETA SM Becomes Available A Appendix A to Part 208 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE MANAGEMENT OF FEDERAL AGENCY DISBURSEMENTS Pt....

  8. 31 CFR Appendix B to Part 208 - Model Disclosure for Use After ETA SM Becomes Available

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Model Disclosure for Use After ETA SM Becomes Available B Appendix B to Part 208 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE MANAGEMENT OF FEDERAL AGENCY DISBURSEMENTS Pt....

  9. THE EMISSION PROCESSING SYSTEM FOR THE ETA/CMAQ AIR QUALITY FORECAST SYSTEM

    EPA Science Inventory

    NOAA and EPA have created an Air Quality Forecast (AQF) system. This AQF system links an adaptation of the EPA's Community Multiscale Air Quality Model with the 12 kilometer ETA model running operationally at NOAA's National Center for Environmental Predication (NCEP). One of th...

  10. Validation of the coupled Eta/SSiB model over South America

    NASA Astrophysics Data System (ADS)

    Chou, Sin Chan; Tanajura, Clemente A. S.; Xue, Yongkang; Nobre, Carlos A.

    2002-10-01

    Two 1-month integrations were performed with the regional Eta model coupled with the Simplified Simple Biosphere model (SSiB) over South America. The goal of the present work is to validate the model and to investigate its biases and skill on the simulations of South American climate. This is an initial step on the use of this model for climate research. The Eta model was set up with 80-km horizontal resolution and 38 vertical layers over the South American continent and part of the adjacent oceans. Analyses from the National Centers for Environmental Prediction (NCEP) were used as initial and lateral boundary conditions. The selected months were August and November 1997, which are in opposite phases of the precipitation annual cycle observed in the central part of South America. The model was integrated continuously for each 1-month period. Monthly means and daily variations of simulated precipitation and surface temperature compare well with observations. The patterns of simulated outgoing longwave radiation are also similar to the observed ones. However, a positive bias is verified in the simulations. The model shows a positive bias in latent and sensible heat surface fluxes due to an excessive shortwave incoming radiation at the surface. Comparisons with a version of the Eta model coupled with the bucket model shows that the Eta/SSiB version improves the surface temperature and increases precipitation in the interior of the continent during wet months.

  11. VizieR Online Data Catalog: BVRI light curves of {eta} Car (Fernandez-Lajus+, 2009)

    NASA Astrophysics Data System (ADS)

    Fernandez-Lajus, E.; Farina, C.; Torres, A. F.; Schwartz, M. A.; Salerno, N.; Calderon, J. P.; von Essen, C.; Calcaferro, L. M.; Giudici, F.; Llinares, C.; Niemela, V.

    2008-11-01

    The periodicity of 5.5 years for some observational events occurring in {eta} Carinae manifests itself across a large wavelength range and has been associated with its binary nature. These events are supposed to occur when the binary components are close to periastron. To detect the previous periastron passage of {eta} Car in 2003, we started an intensive, ground-based, optical, photometric observing campaign. We continued observing the object to monitor its photometric behavior and variability across the entire orbital cycle. Our observation program consisted of daily differential photometry from CCD images, which were acquired using a 0.8m telescope and a standard BVRI filter set at La Plata Observatory. The photometry includes the central object and the surrounding Homunculus nebula. We present up-to-date results of our observing program, including homogeneous photometric data collected between 2003 and 2008. Our observations demonstrated that {eta} Car has continued increasing in brightness at a constant rate since 1998. In 2006, it reached its brightest magnitude (V~4.7) since about 1860s. The object then suddenly reverted its brightening trend, fading to V=5.0 at the beginning of 2007, and has maintained a quite steady state since then. We continue the photometric monitoring of {eta} Car in anticipation of the next "periastron passage", predicted to occur at the beginning of 2009. (2 data files).

  12. Vector performance analysis of three supercomputers - Cray-2, Cray Y-MP, and ETA10-Q

    NASA Technical Reports Server (NTRS)

    Fatoohi, Rod A.

    1989-01-01

    Results are presented of a series of experiments to study the single-processor performance of three supercomputers: Cray-2, Cray Y-MP, and ETA10-Q. The main object of this study is to determine the impact of certain architectural features on the performance of modern supercomputers. Features such as clock period, memory links, memory organization, multiple functional units, and chaining are considered. A simple performance model is used to examine the impact of these features on the performance of a set of basic operations. The results of implementing this set on these machines for three vector lengths and three memory strides are presented and compared. For unit stride operations, the Cray Y-MP outperformed the Cray-2 by as much as three times and the ETA10-Q by as much as four times for these operations. Moreover, unlike the Cray-2 and ETA10-Q, even-numbered strides do not cause a major performance degradation on the Cray Y-MP. Two numerical algorithms are also used for comparison. For three problem sizes of both algorithms, the Cray Y-MP outperformed the Cray-2 by 43 percent to 68 percent and the ETA10-Q by four to eight times.

  13. BICEP's acceleration

    SciTech Connect

    Contaldi, Carlo R.

    2014-10-01

    The recent Bicep2 [1] detection of, what is claimed to be primordial B-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of e-fold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup -3} Mpc {sup -1}. This is in agreement with a previous detection of a suppression in the scalar power [2].

  14. FINDING {eta} CAR ANALOGS IN NEARBY GALAXIES USING SPITZER. I. CANDIDATE SELECTION

    SciTech Connect

    Khan, Rubab; Stanek, K. Z.; Kochanek, C. S. E-mail: kstanek@astronomy.ohio-state.edu

    2013-04-10

    The late-stage evolution of the most massive stars such as {eta} Carinae is controlled by the effects of mass loss, which may be dominated by poorly understood eruptive mass ejections. Understanding this population is challenging because no true analogs of {eta} Car have been clearly identified in the Milky Way or other galaxies. We utilize Spitzer IRAC images of seven nearby ({approx}< 4 Mpc) galaxies to search for such analogs. We find 34 candidates with a flat or rising mid-IR spectral energy distributions toward longer mid-infrared wavelengths that emit >10{sup 5} L{sub Sun} in the IRAC bands (3.6 to 8.0 {mu}m) and are not known to be background sources. Based on our estimates for the expected number of background sources, we expect that follow-up observations will show that most of these candidates are not dust enshrouded massive stars, with an expectation of only 6 {+-} 6 surviving candidates. Since we would detect true analogs of {eta} Car for roughly 200 years post-eruption, this implies that the rate of eruptions like {eta} Car is less than the core-collapse supernova rate. It is possible, however, that every M > 40 M{sub Sun} star undergoes such eruptions given our initial results. In Paper II we will characterize the candidates through further analysis and follow-up observations, and there is no barrier to increasing the galaxy sample by an order of magnitude. The primary limitation of the present search is that Spitzer's resolution limits us to the shorter wavelength IRAC bands. With the James Webb Space Telescope, such surveys can be carried out at the far more optimal wavelengths of 10-30 {mu}m, allowing identification of {eta} Car analogs for millennia rather than centuries post-eruption.

  15. Cardiac-Specific Knockout of ETA Receptor Mitigates Paraquat-Induced Cardiac Contractile Dysfunction.

    PubMed

    Wang, Jiaxing; Lu, Songhe; Zheng, Qijun; Hu, Nan; Yu, Wenjun; Li, Na; Liu, Min; Gao, Beilei; Zhang, Guoyong; Zhang, Yingmei; Wang, Haichang

    2016-07-01

    Paraquat (1,1'-dim ethyl-4-4'-bipyridinium dichloride), a highly toxic quaternary ammonium herbicide widely used in agriculture, exerts potent toxic prooxidant effects resulting in multi-organ failure including the lung and heart although the underlying mechanism remains elusive. Recent evidence suggests possible involvement of endothelin system in paraquat-induced acute lung injury. This study was designed to examine the role of endothelin receptor A (ETA) in paraquat-induced cardiac contractile and mitochondrial injury. Wild-type (WT) and cardiac-specific ETA receptor knockout mice were challenged to paraquat (45 mg/kg, i.p.) for 48 h prior to the assessment of echocardiographic, cardiomyocyte contractile and intracellular Ca(2+) properties, as well as apoptosis and mitochondrial damage. Levels of the mitochondrial proteins for biogenesis and oxidative phosphorylation including UCP2, HSP90 and PGC1α were evaluated. Our results revealed that paraquat elicited cardiac enlargement, mechanical anomalies including compromised echocardiographic parameters (elevated left ventricular end-systolic and end-diastolic diameters as well as reduced factional shortening), suppressed cardiomyocyte contractile function, intracellular Ca(2+) handling, overt apoptosis and mitochondrial damage. ETA receptor knockout itself failed to affect myocardial function, apoptosis, mitochondrial integrity and mitochondrial protein expression. However, ETA receptor knockout ablated or significantly attenuated paraquat-induced cardiac contractile and intracellular Ca(2+) defect, apoptosis and mitochondrial damage. Taken together, these findings revealed that endothelin system in particular the ETA receptor may be involved in paraquat-induced toxic myocardial contractile anomalies possibly related to apoptosis and mitochondrial damage. PMID:26089164

  16. A Nonparametric Bayesian Approach to Seismic Hazard Modeling Using the ETAS Framework

    NASA Astrophysics Data System (ADS)

    Ross, G.

    2015-12-01

    The epidemic-type aftershock sequence (ETAS) model is one of the most popular tools for modeling seismicity and quantifying risk in earthquake-prone regions. Under the ETAS model, the occurrence times of earthquakes are treated as a self-exciting Poisson process where each earthquake briefly increases the probability of subsequent earthquakes occurring soon afterwards, which captures the fact that large mainshocks tend to produce long sequences of aftershocks. A triggering kernel controls the amount by which the probability increases based on the magnitude of each earthquake, and the rate at which it then decays over time. This triggering kernel is usually chosen heuristically, to match the parametric form of the modified Omori law for aftershock decay. However recent work has questioned whether this is an appropriate choice. Since the choice of kernel has a large impact on the predictions made by the ETAS model, avoiding misspecification is crucially important. We present a novel nonparametric version of ETAS which avoids making parametric assumptions, and instead learns the correct specification from the data itself. Our approach is based on the Dirichlet process, which is a modern class of Bayesian prior distribution which allows for efficient inference over an infinite dimensional space of functions. We show how our nonparametric ETAS model can be fit to data, and present results demonstrating that the fit is greatly improved compared to the standard parametric specification. Additionally, we explain how our model can be used to perform probabilistic declustering of earthquake catalogs, to classify earthquakes as being either aftershocks or mainshocks. and to learn the causal relations between pairs of earthquakes.

  17. Exploring and Modeling High-excitation Emission in the Ejecta and the Wind of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Mehner, Andrea

    Eta Carinae is the most massive, most luminous star in our region of the Galaxy. It is an evolved massive star and therefore provides many clues to the fate of the most massive stars. In the 1840s its unstable nature culminated in the Great Eruption when it briefly became the second brightest star in the sky and ejected more than ten solar masses, which today enshroud the surviving star as a bipolar nebula. Every 5.54 years Eta Car's photometry and spectra show dramatic changes which last for several months. Combining data from HST/STIS, Gemini-S/GMOS, and VLT/UVES from 1998 to 2010, I analyzed two spectroscopic cycles. Observations with a variety of different slit position angles made it possible to map the emission across the nebula and the complex outer ejecta of Eta Car permit to observe the star at different stellar latitudes via reflected light. The spectroscopic cycles are thought to be regulated by a hot companion star and therefore give us information to the nature and orbit of the stars hidden behind Eta Car's opaque wind. The observations, covering more than 10 years, made it also possible to observe the ongoing long-term recovery from the Great Eruption. Topics covered in this thesis include: 1) spatial and temporal behavior of the high-excitation emission lines, 2) parameters of the secondary star, 3) He II 4687 emission during the 2009 "Event," 4) changing wind structure during the 2009 "Event," 5) origin of the He I lines, and 6) major changes in the broad-line wind spectrum indicating a decrease in Eta Car's wind density.

  18. Observation of the Exclusive Reaction e^+e^-\\ to \\phi\\eta at \\sqrt{s}=10.58 GeV

    SciTech Connect

    Aubert, B.

    2006-11-17

    The authors report the observation of e{sup +}e{sup -} {yields} {phi}{eta} near {radical}s = 10.58 GeV with 6.5 {sigma} significance in the K{sup +}K{sup -}{gamma}{gamma} final state in a data sample of 224 fb{sup -1} collected by the BABAR experiment at the PEP-II e{sup +}e{sup -} storage rings. They measure the restricted radiation-corrected cross section to be {sigma}(e{sup +}e{sup -} {yields} {phi}{eta}) = 2.1 {+-} 0.4(stat) {+-} 0.1(syst) fb within the range |cos{theta}*| < 0.8, where {theta}* is the center-of-mass polar angle of the {phi} meson. The {phi} meson is required to be in the invariant mass range of 1.008 < m{sub {phi}} < 1.035 GeV/c{sup 2}. The radiation corrected cross section in the full cos {theta}* range is extrapolated to be 2.9 {+-} 0.5(stat) {+-} 0.1(syst) fb.

  19. Measurement of branching fractions and charge asymmetries in B decays to an eta meson and a K* meson.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; del Amo Sanchez, P; Barrett, M; Ford, K E; Hart, A J; Harrison, T J; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Bard, D J; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Safai Tehrani, F; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; De Groot, N; Franek, B; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Legendre, M; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Mellado, B; Mihalyi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2006-11-17

    We present measurements of branching fractions and charge asymmetries for the decays B-->etaK*, where K* indicates a spin 0, 1, or 2 Kpi system. The data sample corresponds to 344x10(6) BB pairs collected with the BABAR detector at the PEP-II asymmetric-energy e+ e- collider at SLAC. We measure the branching fractions (in units of 10(-6): B(B0-->etaK*0(892))=16.5+/-1.1+/-0.8, B(B+-->etaK*+(892))=18.9+/-1.8+/-1.3, B(B0-->eta(Kpi)0*0)=11.0+/-1.6+/-1.5, B(B+-->eta(Kpi)0*+)=18.2+/-2.6+/-2.6, B(B0-->etaK2*0(1430))=9.6+/-1.8+/-1.1, and B(B+-->etaK2*+(1430))=9.1+/-2.7+/-1.4. We also determine the charge asymmetries for all decay modes. PMID:17155674

  20. Review of ion accelerators

    SciTech Connect

    Alonso, J.

    1990-06-01

    The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here.

  1. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  2. Accelerators and the Accelerator Community

    SciTech Connect

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  3. A new measurement of the rare decay eta -> pi^0 gamma gamma with the Crystal Ball/TAPS detectors at the Mainz Microtron

    SciTech Connect

    Nefkens, B M; Prakhov, S; Aguar-Bartolom��, P; Annand, J R; Arends, H J; Bantawa, K; Beck, R; Bekrenev, V; Bergh��user, H; Braghieri, A; Briscoe, W J; Brudvik, J; Cherepnya, S; Codling, R F; Collicott, C; Costanza, S; Danilkin, I V; Denig, A; Demissie, B; Dieterle, M; Downie, E J; Drexler, P; Fil'kov, L V; Fix, A; Garni, S; Glazier, D I; Gregor, R; Hamilton, D; Heid, E; Hornidge, D; Howdle, D; Jahn, O; Jude, T C; Kashevarov, V L; K��ser, A; Keshelashvili, I; Kondratiev, R; Korolija, M; Kotulla, M; Koulbardis, A; Kruglov, S; Krusche, B; Lisin, V; Livingston, K; MacGregor, I J; Maghrbi, Y; Mancel, J; Manley, D M; McNicoll, E F; Mekterovic, D; Metag, V; Mushkarenkov, A; Nikolaev, A; Novotny, R; Oberle, M; Ortega, H; Ostrick, M; Ott, P; Otte, P B; Oussena, B; Pedroni, P; Polonski, A; Robinson, J; Rosner, G; Rostomyan, T; Schumann, S; Sikora, M H; Starostin, A; Strakovsky, I I; Strub, T; Suarez, I M; Supek, I; Tarbert, C M; Thiel, M; Thomas, A; Unverzagt, M; Watts, D P; Werthmueller, D; Witthauer, L

    2014-08-01

    A new measurement of the rare, doubly radiative decay eta->pi^0 gamma gamma was conducted with the Crystal Ball and TAPS multiphoton spectrometers together with the photon tagging facility at the Mainz Microtron MAMI. New data on the dependence of the partial decay width, Gamma(eta->pi^0 gamma gamma), on the two-photon invariant mass squared, m^2(gamma gamma), as well as a new, more precise value for the decay width, Gamma(eta->pi^0 gamma gamma) = (0.33+/-0.03_tot) eV, are based on analysis of 1.2 x 10^3 eta->pi^0 gamma gamma decays from a total of 6 x 10^7 eta mesons produced in the gamma p -> eta p reaction. The present results for dGamma(eta->pi^0 gamma gamma)/dm^2(gamma gamma) are in good agreement with previous measurements and recent theoretical calculations for this dependence.

  4. Eta' photoproduction on the proton for photon energies from 1.527 to 2.227 GeV.

    PubMed

    Dugger, M; Ball, J P; Collins, P; Pasyuk, E; Ritchie, B G; Adams, G; Ambrozewicz, P; Anciant, E; Anghinolfi, M; Asavapibhop, B; Asryan, G; Audit, G; Avakian, H; Bagdasaryan, H; Baillie, N; Baltzell, N A; Barrow, S; Batourine, V; Battaglieri, M; Beard, K; Bedlinskiy, I; Bektasoglu, M; Bellis, M; Benmouna, N; Berman, B L; Bianchi, N; Biselli, A S; Bonner, B E; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Burkert, V D; Butuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Carnahan, B; Chen, S; Cole, P L; Coleman, A; Coltharp, P; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Credé, V; Cummings, J P; De Sanctis, E; DeVita, R; Degtyarenko, P V; Denizli, H; Dennis, L; Deur, A; Dharmawardane, K V; Dhuga, K S; Djalali, C; Dodge, G E; Donnelly, J; Doughty, D; Dragovitsch, P; Dytman, S; Dzyubak, O P; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Empl, A; Eugenio, P; Fatemi, R; Fedotov, G; Feldman, G; Feuerbach, R J; Forest, T A; Funsten, H; Garçon, M; Gavalian, G; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gothe, R W; Griffioen, K A; Guidal, M; Guillo, M; Guler, N; Guo, L; Gyurjyan, V; Hadjidakis, C; Hakobyan, R S; Hardie, J; Heddle, D; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hu, J; Huertas, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Ito, M M; Jenkins, D; Jo, H S; Joo, K; Juengst, H G; Kellie, J D; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klimenko, A V; Klusman, M; Kossov, M; Kramer, L H; Kubarovsky, V; Kuhn, J; Kuhn, S E; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Lee, T; Lima, A C S; Livingston, K; Lukashin, K; Manak, J J; Marchand, C; Maximon, L C; McAleer, S; McKinnon, B; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Minehart, R; Mirazita, M; Miskimen, R; Mokeev, V; Morrow, S A; Muccifora, V; Mueller, J; Mutchler, G S; Nadel-Turonski, P; Napolitano, J; Nasseripour, R; Niccolai, S; Niculescu, G; Niczyporuk, B B; Niyazov, R A; Nozar, M; O'Rielly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Paterson, C; Philips, S A; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ronchetti, F; Rosner, G; Rossi, P; Rowntree, D; Rubin, P D; Sabatié, F; Salgado, C; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Shafi, A; Sharabian, Y G; Shaw, J; Simionatto, S; Skabelin, A V; Smith, E S; Smith, L C; Sober, D I; Spraker, M; Stavinsky, A; Stepanyan, S S; Stepanyan, S; Stokes, B E; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Taylor, S; Tedeschi, D J; Thoma, U; Thompson, R; Tkabladze, A; Tkachenko, S; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A V; Wang, K; Weinstein, L B; Weller, H; Weygand, D P; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Zana, L; Zhang, J

    2006-02-17

    Differential cross sections for the reaction gamma p --> eta' p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data suggest for the first time the coupling of the eta'N channel to both the S11(1535) and P11(1710) resonances, known to couple strongly to the etaN channel in photoproduction on the proton, and the importance of J = 3/2 resonances in the process. PMID:16605984

  5. Measurement of the transverse momentum and $$\\phi ^*_{\\eta }$$ distributions of Drell–Yan lepton pairs in proton–proton collisions at $$\\sqrt{s}=8$$ TeV with the ATLAS detector

    DOE PAGESBeta

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2016-05-23

    Distributions of transverse momentum pTℓℓ and the related angular variablemore » $$\\phi ^*_{\\eta }$$ of Drell-Yan lepton pairs are measured in 20.3 fb–1 of proton-proton collisions at √s=8 TeV with the ATLAS detector at the LHC. Measurements in electron-pair and muon-pair final states are corrected for detector effects and combined. Compared to previous measurements in protonΓÇôproton collisions at √s=7 TeV these new measurements benefit from a larger data sample and improved control of systematic uncertainties. Measurements are performed in bins of lepton-pair mass above, around and below the Z -boson mass peak. The data are compared to predictions from perturbative and resummed QCD calculations. For values of $$\\phi ^*_{\\eta }$$<1 the predictions from the Monte Carlo generator ResBos are generally consistent with the data within the theoretical uncertainties. However, at larger values of $$\\phi ^*_{\\eta }$$ this is not the case. Monte Carlo generators based on the parton-shower approach are unable to describe the data over the full range of pTℓℓ while the fixed-order prediction of Dynnlo falls below the data at high values of pTℓℓ. Here, ResBos and the parton-shower Monte Carlo generators provide a much better description of the evolution of the $$\\phi ^*_{\\eta }$$ and pTℓℓ distributions as a function of lepton-pair mass and rapidity than the basic shape of the data.« less

  6. Dicarbollylamine ligand as a tunable template for sigma,sigma- and pi,sigma-bonding modes: syntheses, structures, and theoretical studies of eta5:eta1-coordinated constrained-geometry group 13 metal complexes.

    PubMed

    Lee, Jong-Dae; Kim, Sung-Kwan; Kim, Tae-Jin; Han, Won-Sik; Lee, Young-Joo; Yoo, Dae-Hwan; Cheong, Minserk; Ko, Jaejung; Kang, Sang Ook

    2008-07-30

    A series of group 13 main group complexes with pi,sigma-type bonding interaction of the formula [{(eta (5)-RC 2B 9H 9)(CH 2)(eta (1)-NMe 2)}MMe] (M = Al, R = H 5, Me 6; Ga, R = H 7, Me 8; In, R = H 9, Me 10) was produced by the reaction of group 13 metal alkyls (MMe 3; M = Al, Ga, In) with the dicarbollylamine ligands, nido-8-R-7,8-C 2B 9H 10-7-(CH 2)NHMe 2 (R = H 1, Me 2). The reactions of 1 and 2 with AlMe 3 in toluene initially afforded tetra-coordinated aluminum complexes with sigma,sigma-type bonding interaction, [{(eta (1)-RC 2B 9H 10)(CH 2)(eta (1)-NMe 2)}AlMe 2] (R = H 3, Me 4), which readily underwent further methane elimination to yield the corresponding constrained geometry complexes (CGCs, 5 and 6) of aluminum with pi,sigma-bonding interaction. However, the reactions between 1 and 2 and MMe 3 (M = Ga, In) in toluene produced gallium and indium pi,sigma-CGCs of 7 and 10 directly, not proceeding through sigma,sigma-intermediates. The structures of group 13 metal CGCs were established by X-ray diffraction studies of 5, 6, and 8, which authenticated a characteristic eta (5):eta (1)-coordination mode of the dicarbollylamino ligand to the group 13 metals. A similar pi,sigma-bonding interaction was also established in ethylene-bridged dicarbollylethylamine series. Thus, aluminum pi,sigma-CGCs of dicarbollylethylamine, [{(eta (5)-RC 2B 9H 9)(CH 2) 2(eta (1)-NBz 2)}AlMe] (R = H 17, Me 18), were prepared by the trans-metalation of the [{(eta (5)-RC 2B 9H 9)(CH 2) 2(eta (1)-NBz 2)}Ti(NMe 2) 2] (R = H 15, Me 16) with AlMe 3. However, only sigma,sigma-bonded complexes of the formula [{(eta (1)-RC 2B 9H 9)(CH 2) 2(eta (1)-NBz 2)}AlMe 2] (R = H 13, Me 14) were isolated by the reaction between [ nido-7-8-R-7,8-C 2B 9H 10-(CH 2) 2HNBz 2] (R = H 11, Me 12) and AlMe 3. When methane-elimination reactions between metal alkyls and dicarbollylamines were carried out with either the gallium atom or monobenzyl aminoethyl tethered ligands, [ nido-7-H 2NBz(CH 2) 2-8-R-7,8-C 2B 9H

  7. An upgraded version of the Eta Model applied to Antarctic case studies

    NASA Astrophysics Data System (ADS)

    Morelli, S.

    2012-04-01

    Upgrades have been implemented over a number of years in an open source version of the Eta Model, posted at its CPTEC web site (http://etamodel.cptec.inpe.br/). They were summarized in Mesinger et al. (2011) and examined in detail in Mesinger et al.( 2012). In short: within dynamics, two major upgrades are the introduction of "sloping steps" and the use of the piecewise-linear vertical advection of dynamic variables. Several refinements on the calculation of exchange coefficients, conservation in the vertical diffusion, and diagnostic calculation of 10-m winds have been made. Vapor and hydrometeor loading in the hydrostatic equation were included. Within physics, efforts in refining the two Eta convection schemes received most attention. This recent version of the Eta Model has been applied to polynya events, accompanied by katabatic wind, at Terra Nova Bay (TNB), Antarctica. The TNB polynya is an area of coupling between the components of the sea ice-ocean-atmosphere system. Locally enhanced surface exchange processes are considered to have important consequences for the atmosphere (Morelli, 2011) and ocean processes, as well as for ice formation and the associated brine release. Adjustments of the Eta pre-processor have been made to allow for the distinctive polar conditions and for the use of ECMWF data as initial and boundary conditions. It is also being developed a thermodynamic model of sea ice interaction for a more realistic treatment of the sea ice-atmosphere. The numerical simulations have a horizontal resolution of about 8 Km. The results will be compared with observational data at the surface, with soundings and satellite images. The observations, used for the comparison, are available by Antarctic Meteorological Research Center, Space Science and Engineering Center, University of Wisconsin-Madison and the Programma Nazionale di Ricerche in Antartide (P.N.R.A.), Osservatorio Meteo-Climatologico. F Mesinger, Chou S C, Gomes J, Jovic D, Lazic L, Lyra A

  8. Testing 3D SPH Models Of Eta Carina's Winds By HST, RXTE, VLT And VLTI Observations

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Madura, T.; Groh, J.; Weigelt, G.; Corcoran, M.; Owocki, S.; Russell, C.; Okazaki, A.

    2011-01-01

    Observations of Eta Carina have been combined with three-dimensional smoothed-particle hydrodynamic (3DSPH) simulations providing considerable insight on this >100 Mo binary that may become near-term supernovae, a GRB, or a staid WR binary. Understanding how this system loses 1e-3 Mo/yr, 500 km/s will provide new understanding of massive stellar evolution, including the first progenitors of GRBs, supernovae and pseudo-supernovae. The 3DSPH models extend to 100 semi-major axes ( 2000 AU, <2” at 2300 pc). At these scales, HST/STIS resolves [Fe III] and [Fe II] spatial-velocity structures that change with orbital phase and position angle. Radiative transfer models combining temperature and density with EtaCar B's FUV lead to synthetic spectroimages of extended wind-wind interfaces. Model X-ray light curves provide orbital inclination and location of periastron but cannot determine sky PA. Synthetic spectro-images generated for a range of possible binary orientations lead to best-fit when the orbital axis is closely aligned with the Homunculus axis of symmetry, and periastron with EtaCar B on the far side of EtaCar A. VLTI/AMBER measures of the continuum, extended hydrogen and helium structures of EtaCar A demonstrate that, across periastron, EtaCar B penetrates the primary extended atmosphere. Spectroimagery observations of He 10830 by VLT/CRIRES show blue-shifted emission extending to -1500 km/s, consistent with wind-wind structures driven by the companion's fast wind. The 2009.0 RXTE X-ray recovery and return of the spectroscopic high state was much sooner than the 1998.0 and 2003.5 recoveries. What has changed? Suggestions range from a drop in the primary wind, changes in the secondary wind or line-of-sight shifting of the wind-wind boundary. We will discuss potential observational tests based upon predictions by 3DSPH models.

  9. An efficient high power microwave source at 35 GHz using an induction linac free electron accelerator

    SciTech Connect

    Clark, J.C.; Orzechowski, T.J.; Yarema, S.M.

    1986-11-01

    The Electron Laser Facility (ELF) is a free-electron laser (FEL) amplifier operating in the millimeter-wave regime. ELF uses the electron beam produced by the Experimental Test Accelerator (ETA), which is a linear-induction accelerator. We discuss here (1) the experimental results reflecting the high-peak-power output and high-extraction efficiency obtained from an FEL amplifier operated with a tapered wiggler magnetic field and (2) the results of studies of the exponential gain and saturated power obtained from an FEL amplifier with a flat wiggler while we parametrically varied the input power to the amplifier and the beam current into the wiggler.

  10. Measurement of time dependent CP asymmetry parameters in B{sup 0} meson decays to {omega}K{sub S}{sup 0}, {eta}{sup '}K{sup 0}, and {pi}{sup 0}K{sub S}{sup 0}

    SciTech Connect

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G. S.; Battaglia, M.; Brown, D. N.; Cahn, R. N.

    2009-03-01

    We present measurements of the time-dependent CP-violation parameters S and C in the decays B{sup 0}{yields}{omega}K{sub S}{sup 0}, B{sup 0}{yields}{eta}{sup '}K{sup 0}, reconstructed as {eta}{sup '}K{sub S}{sup 0} and {eta}{sup '}K{sub L}{sup 0}, and B{sup 0}{yields}{pi}{sup 0}K{sub S}{sup 0}. The data sample corresponds to the full BABAR dataset of 467x10{sup 6} BB pairs produced at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the Stanford Linear Accelerator Center. The results are S{sub {omega}}{sub K{sub S}{sup 0}}=0.55{sub -0.29}{sup +0.26}{+-}0.02, C{sub {omega}}{sub K{sub S}{sup 0}}=-0.52{sub -0.20}{sup +0.22}{+-}0.03, S{sub {eta}{sup '}}{sub K{sup 0}}=0.57{+-}0.08{+-}0.02, C{sub {eta}{sup '}}{sub K{sup 0}}=-0.08{+-}0.06{+-}0.02, S{sub {pi}{sup 0}}{sub K{sub S}{sup 0}}=0.55{+-}0.20{+-}0.03, and C{sub {pi}{sup 0}}{sub K{sub S}{sup 0}}=0.13{+-}0.13{+-}0.03, where the first errors are statistical and the second systematic. These results are consistent with our previous measurements and the world average of sin2{beta} measured in B{sup 0}{yields}J/{psi}K{sub S}{sup 0}.

  11. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  12. Attention's Accelerator.

    PubMed

    Reinhart, Robert M G; McClenahan, Laura J; Woodman, Geoffrey F

    2016-06-01

    How do people get attention to operate at peak efficiency in high-pressure situations? We tested the hypothesis that the general mechanism that allows this is the maintenance of multiple target representations in working and long-term memory. We recorded subjects' event-related potentials (ERPs) indexing the working memory and long-term memory representations used to control attention while performing visual search. We found that subjects used both types of memories to control attention when they performed the visual search task with a large reward at stake, or when they were cued to respond as fast as possible. However, under normal circumstances, one type of target memory was sufficient for slower task performance. The use of multiple types of memory representations appears to provide converging top-down control of attention, allowing people to step on the attentional accelerator in a variety of high-pressure situations. PMID:27056975

  13. Electrothermal Annealing (ETA) Method to Enhance the Electrical Performance of Amorphous-Oxide-Semiconductor (AOS) Thin-Film Transistors (TFTs).

    PubMed

    Kim, Choong-Ki; Kim, Eungtaek; Lee, Myung Keun; Park, Jun-Young; Seol, Myeong-Lok; Bae, Hagyoul; Bang, Tewook; Jeon, Seung-Bae; Jun, Sungwoo; Park, Sang-Hee K; Choi, Kyung Cheol; Choi, Yang-Kyu

    2016-09-14

    An electro-thermal annealing (ETA) method, which uses an electrical pulse of less than 100 ns, was developed to improve the electrical performance of array-level amorphous-oxide-semiconductor (AOS) thin-film transistors (TFTs). The practicality of the ETA method was experimentally demonstrated with transparent amorphous In-Ga-Zn-O (a-IGZO) TFTs. The overall electrical performance metrics were boosted by the proposed method: up to 205% for the trans-conductance (gm), 158% for the linear current (Ilinear), and 206% for the subthreshold swing (SS). The performance enhancement were interpreted by X-ray photoelectron microscopy (XPS), showing a reduction of oxygen vacancies in a-IGZO after the ETA. Furthermore, by virtue of the extremely short operation time (80 ns) of ETA, which neither provokes a delay of the mandatory TFTs operation such as addressing operation for the display refresh nor demands extra physical treatment, the semipermanent use of displays can be realized. PMID:27552134

  14. A New Measurement of {eta}{sub b}(1S) From {Upsilon}(3S) Radiative Decay at CLEO

    SciTech Connect

    Dobbs, Sean

    2010-08-05

    Using CLEO data, we report on the confirmation of the {eta}{sub b}({sup 1}S{sub 0}) ground state of bottomonium in the radiative decay {Upsilon}(3S){yields}{gamma}{eta}{sub b} We determine its mass to be M({eta}{sub b}) = 9391.8{+-}6.6{+-}2.1 MeV, which corresponds to the hyperfine splitting {Delta}M{sub hf}(1S) = 68.5{+-}6.6{+-}2.0 MeV, and the branching fraction B({Upsilon}(3S){gamma}{eta}{sub b}) = (7.1{+-}1.8{+-}1.1)x10{sup -4}. These results agree with those previously reported by BaBar.

  15. Berkeley Proton Linear Accelerator

    DOE R&D Accomplishments Database

    Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.

    1953-10-13

    A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.

  16. Measurement of th eta and etaprime Transition Form Factors at q^2 = 112 GeV^2

    SciTech Connect

    Aubert, B.

    2006-05-16

    The authors report a study of the processes e{sup +}e{sup -} {yields} {eta}{gamma} and e{sup +}e{sup -} {yields} {eta}'{gamma} at a center-of-mass energy of 10.58 GeV, using a 232 fb{sup -1} data sample collected with the BABAR detector at the PEP-II collider at SLAC.

  17. RHIC sextant test: Accelerator systems and performance

    SciTech Connect

    Pilat, F.; Trbojevic, D.; Ahrens, L.

    1997-08-01

    One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning.

  18. Transition Metal Complexes of Cr, Mo, W and Mn Containing {eta}{sup 1}(S)-2,5-Dimethylthiophene, Benzothiophene and Dibenzothiophene Ligands

    SciTech Connect

    Reynolds, M.

    2000-09-21

    The UV photolysis of hexanes solutions containing the complexes M(CO){sub 6} (M=Cr, Mo, W) or CpMn(CO){sub 3} (Cp={eta}{sup 5}-C{sub 5}H{sub 5}) and excess thiophene (T{sup *}) (T{sup *}=2,5-dimethylthiophene (2,5-Me{sub 2}T), benzothiophene (BT), and dibenzothiophene (DBT)) produces the {eta}{sup 1}(S)-T{sup *} complexes (CO){sub 5}M({eta}{sup 1}(S)-T{sup *}) 1-8 or Cp(CO){sub 2}Mn({eta}{sup 1}(S)-T{sup *})9-11, respectively. However, when T{sup *}=DBT, and M=Mo, a mixture of two products result which includes the {eta}{sup 1}(S)-DBT complex (CO){sub 5}Mo({eta}{sup 1}(S)-DBT) 4a and the unexpected {pi}-complex (CO){sub 3}Mo({eta}{sup 6}-DBT) 4b as detected by {sup 1}H NMR. The liability of the {eta}{sup 1}(S)-T{sup *} ligands is illustrated by the rapid displacement of DBT in the complex (CO){sub 5}W({eta}{sup 1}(S)-DBT) (1) by THF, and also in the complexes (CO){sub 5}Cr({eta}{sup 1}(S)-DBT) (5) and CpMn(CO){sub 2}({eta}{sup 1}(S)-DBT) (9) by CO (1 atm) at room temperature. Complexes 1-11 have been characterized spectroscopically ({sup 1}H NMR, IR) and when possible isolated as analytically pure solids (elemental analysis, EIMS). Single crystal, X-ray structural determinations are reported for (CO){sub 5}W({eta}{sup 1}(S)-DBT) and Cp(CO){sub 2}Mn({eta}{sup 1}(S)-DBT).

  19. Acyclic High-Energy Variability in Eta Carinae and WR 140

    NASA Technical Reports Server (NTRS)

    Corcoran, Michael F.

    2012-01-01

    Eta Carinae and WR 140 are similar long-period colliding wind binaries in which X-ray emission is produced by a strong shock due to the collision of the powerful stellar winds. The change in the orientation and density of this shock as the stars revolve in their orbits influences the X-ray flux and spectrum in a phase dependent way. Monitoring observations with RXTE and other X-ray satellite observatories since the 1990s have detailed this variability but have also shown significant deviations from strict phase dependence (short-term brightness changes or "flares", and cyc1e-to-cyc1e average flux differences). We examine these acylic variations in Eta Car and WR 140 and discuss what they tell us about the stability of the wind-wind collision shock.

  20. The X-ray Variability of Eta Car, 1996-2010

    NASA Technical Reports Server (NTRS)

    Corcoran, Michael F.; Hamaguchi, K.; Gull, T.; Owocki, S.; Pittard, J.

    2010-01-01

    X-ray photometry in the 2-10 keY band of the the supermassive binary star Eta Car has been measured with the Rossi X-ray Timing Explorer from 1996-2010. The ingress to X-ray minimum is consistent with a period of 2024 days. The 2009 X-ray minimum began on January 162009 and showed an unexpectedly abrupt recovery starting after 12 Feb 2009. The X-ray colors become harder about half-way through all three minima and continue until flux recovery. The behavior of the fluxes and X-ray colors for the most recent X-ray minimum, along with Chandra high resolution grating spectra at key phases suggests a significant change in the inner wind of Eta Car, a possible indicator that the star is entering a new unstable phase of mass loss.

  1. Recent X-ray Variability of Eta Car Approaching The X-ray Eclipse

    NASA Technical Reports Server (NTRS)

    Corcoran, M.; Swank, J. H.; Ishibashi, K.; Gull, T.; Humphreys, R.; Damineli, A.; Walborn, N.; Hillier, D. J.; Davidson, K.; White, S. M.

    2002-01-01

    We discuss recent X-ray spectral variability of the supermassive star Eta Car in the interval since the last X-ray eclipse in 1998. We concentrate on the interval just prior to the next X-ray eclipse which is expected to occur in June 2003. We compare the X-ray behavior during the 2001-2003 cycle with the previous cycle (1996-1998) and note similarities and differences in the temporal X-ray behavior. We also compare a recent X-ray observation of Eta Car obtained with the Chandra high energy transmission grating in October 2002 with an earlier observation from Nov 2002, and interpret these results in terms of the proposed colliding wind binary model for the star. In addition we discuss planned observations for the upcoming X-ray eclipse.

  2. JD13 - Eta Carinae in the Context of the Most Massive Stars

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Damineli, Augusto

    2010-11-01

    Eta Car, with its historical outbursts, visible ejecta and massive, variable winds, continues to challenge both observers and modelers. In just the past five years over 100 papers have been published on this fascinating object. We now know it to be a massive binary system with a 5.54-year period. In January 2009, η Car underwent one of its periodic low-states, associated with periastron passage of the two massive stars. This event was monitored by an intensive multi-wavelength campaign ranging from γ-rays to radio. A large amount of data was collected to test a number of evolving models including 3-D models of the massive interacting winds. August 2009 was an excellent time for observers and theorists to come together and review the accumulated studies, as have occurred in four meetings since 1998 devoted to Eta Car. Indeed, η Car behaved both predictably and unpredictably during this most recent periastron, spurring timely discussions.

  3. The detection of companion stars to the Cepheid variables ETA Aquilae and T Monocerotis

    NASA Technical Reports Server (NTRS)

    Mariska, J. T.; Doschek, G. A.; Feldman, U.

    1981-01-01

    Ultraviolet spectra of the classical Cepheid variables eta Aq1 and T Mon at several phases in their periods were obtained with IUE. For eta Aq1 significant ultraviolet emission is detected at wavelengths less than 1600 A, where little flux is expected from classical Cepheids. Furthermore, the emission at wavelengths less than about 1600 A does not vary with phase. Comparison with model atmosphere flux distributions shows that the nonvariable emission is consistent with the flux expected from a main sequence companion star with an effective temperature of about 9500 K (AO V - A1 V). For T Mon a nonvarying component to the ultraviolet emission is observed for wavelengths less than 2600 A. Comparison with model atmosphere flux distributions suggests that the companion has an effective temperature of around 10,000 K (AO) and is near the main sequence.

  4. The Abundance of Iron-Peak Elements and the Dust Composition in eta Carinae: Manganese

    NASA Technical Reports Server (NTRS)

    Bautista, M. A.; Melendez, M.; Hartman, H.; Gull, T. R.; Lodders, K.

    2010-01-01

    We study the chemical abundances of the Strontium Filament found in the ejecta of (eta) Carinae. In particular, we derive the abundances of iron-peak elements front spectra of their singly ionized ions present in the optical/IR spectra. In this paper we analyze the spectrum of Mn II using a new non-LTE model for this system. In constructing this models we carried out theoretical calculations of radiative transition rates and electron impact excitation rate coefficients. We find that relative to Ni the gas phase abundance ratio of Mn is roughly solar, similar to the Cr abundance but in contrast to the large enhancements in the abundances of Sc and Ti. NVe interpret this result as an indication of non-equilibrium condensation in the ejecta of (eta) Carinae.

  5. The Eta Carinae Homunculus in Full 3D with X-Shooter and Shape

    NASA Technical Reports Server (NTRS)

    Steffen, Wolfgang; Teodoro, Mairan; Madura, Thomas I.; Groh, Jose H.; Gull, Theodore R.; Mehner, Andrea; Corcoran, Michael F.; Damineli, Augusto; Hamaguchi, Kenji

    2014-01-01

    Massive stars like Eta Carinae are extremely rare in comparison to stars such as the Sun, and currently we know of only a handful of stars with masses of more than 100 solar mass in the Milky Way. Such massive stars were much more frequent in the early history of the Universe and had a huge impact on its evolution. Even among this elite club, Eta Car is outstanding, in particular because of its giant eruption around 1840 that produced the beautiful bipolar nebula now known as the Homunculus. In this study, we used detailed spatio-kinematic information obtained from X-shooter spectra to reconstruct the 3D structure of the Homunculus. The small-scale features suggest that the central massive binary played a significant role in shaping the Homunculus.

  6. The synthesis and structural characterisation of [Ru(eta-Cp)(dppf)SnBr3].

    PubMed

    Paim, L A; Moura, E M; Siebald, H G L; de Lima, G M; Doriguetto, A C; Ellena, J

    2004-08-01

    The reaction of [Ru(eta-Cp)(dppf)N(3)] (1) with equimolar amount of SnBr(2) yielded an interesting heterotrimetallic compound [Ru(eta-Cp)(dppf)SnBr(3)] (2) (dppf: 1,1'-bis-diphenylphosphinoferrocene). Compounds 1 and 2 were characterised by IR, NMR (1H, 13C, 31P and 119Sn), and 2, additionally, by 57Fe and 119Sn Mössbauer spectroscopy and X-ray crystallography. The latter results were as follows: monoclinic, C2/c, a = 32.8879(4)A, b = 11.9888(2)A, c = 20.8986(3)A, beta = 92.545(1)degrees, V = 8231.9(2)A(3), Z =8. PMID:15249029

  7. Does Turbulence in the Iron Convection Zone Cause the Massive Outbursts of Eta Carinae?

    NASA Technical Reports Server (NTRS)

    Stothers, Richard B.

    1999-01-01

    Taken at face value, the observed properties of the central object in Eta-Car suggest a very massive, hot main-sequence star, only slightly evolved. If this is so, the star's extraordinarily high steady rate of mass loss must dynamically perturb its outer envelope down to the iron convection zone, where the kinetic energy associated with turbulent convection can be directly fed into mass ejection. Runaway mass loss, triggered by either internal (pulsational, rotational) or external (tidal) forcing, would produce a secular oscillation of the outer envelope. In either case, the oscillation is potentially able to account for the observed approximately 5 yr cycles of visual outbursts in Eta-Car, including the giant eruption of 1843.

  8. The steady-state level and stability of TLS polymerase eta are cell cycle dependent in the yeast S. cerevisiae.

    PubMed

    Plachta, Michal; Halas, Agnieszka; McIntyre, Justyna; Sledziewska-Gojska, Ewa

    2015-05-01

    Polymerase eta (Pol eta) is a ubiquitous translesion DNA polymerase that is capable of bypassing UV-induced pyrimidine dimers in an error-free manner. However, this specialized polymerase is error prone when synthesizing through an undamaged DNA template. In Saccharomyces cerevisiae, both depletion and overproduction of Pol eta result in mutator phenotypes. Therefore, regulation of the cellular abundance of this enzyme is of particular interest. However, based on the investigation of variously tagged forms of Pol eta, mutually contradictory conclusions have been reached regarding the stability of this polymerase in yeast. Here, we optimized a protocol for the detection of untagged yeast Pol eta and established that the half-life of the native enzyme is 80 ± 14 min in asynchronously growing cultures. Experiments with synchronized cells indicated that the cellular abundance of this translesion polymerase changes throughout the cell cycle. Accordingly, we show that the stability of Pol eta, but not its mRNA level, is cell cycle stage dependent. The half-life of the polymerase is more than fourfold shorter in G1-arrested cells than in those at G2/M. Our results, in concert with previous data for Rev1, indicate that cell cycle regulation is a general property of Y family TLS polymerases in S. cerevisiae. PMID:25766643

  9. PKC{eta} confers protection against apoptosis by inhibiting the pro-apoptotic JNK activity in MCF-7 cells

    SciTech Connect

    Rotem-Dai, Noa; Oberkovitz, Galia; Abu-Ghanem, Sara; Livneh, Etta

    2009-09-10

    Apoptosis is frequently regulated by different protein kinases including protein kinase C family enzymes. Both inhibitory and stimulatory effects were demonstrated for several of the different PKC isoforms. Here we show that the novel PKC isoform, PKC{eta}, confers protection against apoptosis induced by the DNA damaging agents, UVC irradiation and the anti-cancer drug - Camptothecin, of the breast epithelial adenocarcinoma MCF-7 cells. The induced expression of PKC{eta} in MCF-7 cells, under the control of the tetracycline-responsive promoter, resulted in increased cell survival and inhibition of cleavage of the apoptotic marker PARP-1. Activation of caspase-7 and 9 and the release of cytochrome c were also inhibited by the inducible expression of PKC{eta}. Furthermore, JNK activity, required for apoptosis in MCF-7, as indicated by the inhibition of both caspase-7 cleavage and cytochrome c release from the mitochondria in the presence of the JNK inhibitor SP600125, was also suppressed by PKC{eta} expression. Hence, in contrast to most PKC isoforms enhancing JNK activation, our studies show that PKC{eta} is an anti-apoptotic protein, acting as a negative regulator of JNK activity. Thus, PKC{eta} could represent a target for intervention aimed to reduce resistance to anti-cancer treatments.

  10. Evidence of [eta]' or ordered zone formation in aluminum alloy 7075 from differential scanning calorimetry. [Aluminium alloy 7075

    SciTech Connect

    Bartges, C.W. )

    1993-05-01

    The development of high strength levels in Al-Mg-Zn-(Cu) alloys is dependent on the decomposition of the supersaturated solid solution ([alpha][sub ss]). The equilibrium phase, [eta], and the transition phase, [eta][prime], have compositions Mg(Zn, Al, Cu)[sub 2] and the GP Zones are solute rich clusters. Several authors have presented evidence that there is another precipitate which forms between the GP Zones and [eta][prime], though there is some controversy whether it is crystallographically distinct from the matrix, [eta][prime], or an ordered GP Zone. Regardless of their structure, these particles are seldom observed and are not usually considered in the decomposition of these alloys. Most of the previous observations of these particles have been the result of involved transmission electron microscopic and X-ray scattering experiments. This report shows they may also be detected using differential scanning calorimetry (DSC). Also significant is the fact that the particles were observed in AA 7075, an important commercial alloy. Lloyd and Chaturvedi also saw indications of [eta][prime] or ordered zones using DSC, but the results reported herein are different in several important respects. DSC traces of alloys aged for various times at room temperature and 121 C have shown there is at least one phase which can form during the decomposition of aluminum alloy 7075 that is not usually stated in the decomposition reaction. The results of previous studies suggest they may be ordered GP Zones or [eta][prime].

  11. Decline of the 2-10 keV Emission from Eta Carinae

    NASA Technical Reports Server (NTRS)

    Liburd, Jamar; Corcoran, Michael F.; Hamaguchi, Kenji; Gull, Theodore R.; Madura, Thomas; Teodoro, Mairan; Moffat, Anthony; Richardson, Noel; Russell, Chris; Pollock, Andrew; Owocki, Stan

    2014-01-01

    Analysis of Eta Car's X-ray spectrum in the 2-10 keV band using processed data from the X-ray Telescope on Swift reveals a peak flux on July 16, 2014 of 0.046 photons s(exp -1) cm(exp -2) (3.37+/-0.15×10(exp -10) ergs s(exp -1) cm(exp -2). This flux is similar to the previous maximum flux seen by the XRT, 3.53+/-0.13×10(exp -10) ergs s(exp -1) cm(exp -2) (0.049 photons s(exp -1) cm(exp -2), ATEL #6298). Since this peak on July 16, the most recent Swift XRT quicklook data show a drop in flux. On July 20, 2014 the XRT flux as seen in the quicklook data was 0.011 photons s(exp -1) cm(exp -2) (8.3+/-0.5×10(exp -11) ergs s(exp -1) cm(exp -2)). This most likely indicates that the 2-10 keV flux is in its declining phase as Eta Car approaches its deep X-ray minimum stage (Hamaguchi et al., 2014, ApJ, 784, 125) associated with periastron passage of the 2024-day binary orbit. The column density derived from analysis of the July 20 XRT quicklook data is 7.2×10(exp 22) cm(exp -2). This is consistent with the column density seen near the same orbital phase in 2003 (7.7×10(exp 22) cm(exp -2), Hamaguchi et al., 2007, ApJ, 663, 522). Eta Car's deep X-ray minimum phase is expected to begin on July 30, 2014. Weekly Swift/XRT observations of Eta Car in the 2-10 keV band are planned throughout the X-ray minimum.

  12. Was the nineteenth century giant eruption of Eta Carinae a merger event in a triple system?

    NASA Astrophysics Data System (ADS)

    Portegies Zwart, S. F.; van den Heuvel, E. P. J.

    2016-03-01

    We discuss the events that led to the giant eruption of Eta Carinae, and find that the mid-nineteenth century (in 1838-1843) giant mass-loss outburst has the characteristics of being produced by the merger event of a massive close binary, triggered by the gravitational interaction with a massive third companion star, which is the current binary companion in the Eta Carinae system. We come to this conclusion by a combination of theoretical arguments supported by computer simulations using the Astrophysical Multipurpose Software Environment. According to this model the ˜90 M⊙ present primary star of the highly eccentric Eta Carinae binary system is the product of this merger, and its ˜30 M⊙ companion originally was the third star in the system. In our model, the Homunculus nebula was produced by an extremely enhanced stellar wind, energized by tidal energy dissipation prior to the merger, which enormously boosted the radiation-driven wind mass-loss. The current orbital plane is then aligned with the equatorial plane of the Homunculus, and the symmetric lobes are roughly aligned with the argument of periastron of the current Eta Carina binary. The merger itself then occurred in 1838, which resulted in a massive asymmetric outflow in the equatorial plane of the Homunculus. The 1843 outburst can in our model be attributed to the subsequent encounter when the companion star (once the outermost star in the triple system) plunges through the bloated envelope of the merger product, once when it passed periastron again. We predict that the system has an excess space velocity of order 50 km s-1 in the equatorial plane of the Homunculus. Our triple model gives a viable explanation for the high runaway velocities typically observed in LBVs.

  13. Photoproduction of the eta prime meson in the effective Lagrangian approach

    SciTech Connect

    Mukhopadhyay, N.C.; Zhang, J.F.; Benmerrouche, M.

    1994-04-01

    In the framework of the effective Lagrangian approach, the authors study the {eta}{prime} photoproduction off protons, of great interest at CEBAF I and II. They calculate the contributions from the leading nucleon Born terms, vector meson exchanges, and estimate the resonance contributions, using the transition amplitudes from the recent quark model estimates by Capstick and Roberts. They discuss implications for the CEBAF experiments.

  14. 3D Hydrodynamical and Radiative Transfer Modeling of Eta Carinae's Colliding Winds

    NASA Astrophysics Data System (ADS)

    Madura, Thomas Ignatius; Clementel, Nicola; Gull, Theodore R.; Kruip, Chael J. H.; Paardekooper, Jan-Pieter; Icke, Vincent

    2015-08-01

    We present the results of full 3D hydrodynamical and radiative transfer simulations of the colliding stellar winds in the massive binary system Eta Carinae (Clementel, Madura, et al. 2014, MNRAS, 443, 2475 and Clementel, Madura, et al. 2015, MNRAS, 447, 2445). We accomplish this by applying the SimpleX algorithm for 3D radiative transfer on an unstructured Voronoi-Delaunay grid to 3D smoothed particle hydrodynamics simulations of the binary colliding winds. We use SimpleX to obtain detailed ionization fractions of hydrogen and helium in 3D. We investigate several computational domain sizes and Luminous Blue Variable primary-star mass-loss rates. We show how the SimpleX simulations can be used to generate synthetic spectral data cubes for comparison to data obtained with the Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph as part of a multi-cycle program to map changes in Eta Carinae's spatially extended interacting wind structures across one binary cycle. Comparison of the HST observations to the SimpleX models can help lead to more accurate constraints on the orbital, stellar, and wind parameters of the Eta Carinae system, such as the LBV primary's mass-loss rate and the companion star's temperature and luminosity. We furthermore present new methods of visualizing and interacting with output from complex 3D numerical simulations, including 3D interactive graphics and 3D printing (Madura et al. 2015, arXiv:1503.00716). While we initially focus specifically on Eta Carinae, the methods employed can be applied to numerous other colliding wind (WR 140, WR 137, WR 19) and dusty ‘pinwheel’ (WR 112, WR 104, WR 98a) binary systems. Coupled with 3D hydrodynamical simulations, SimpleX simulations have the potential to help determine the regions where dust can form and survive in these unique objects.

  15. Three-body Final State Interaction in η→3π

    SciTech Connect

    Guo, Peng; Danilkin, Igor V.; Schott, Diane; Fernández-Ramírez, C.; Mathieu, V.; Szczepaniak, Adam P.

    2015-09-11

    We present an unitary dispersive model for the $\\eta \\to 3 \\pi$ decay process based upon the Khuri-Treiman equations which are solved by means of the Pasquier inversion method. The description of the hadronic final-state interactions for the $\\eta \\to 3\\pi$ decay is essential to reproduce the available data and to understand the existing discrepancies between Dalitz plot parameters from experiment and chiral perturbation theory. Our approach incorporates substraction constants that are fixed by fitting the recent high-statistics WASA-at-COSY data for $\\eta \\to \\pi^+ \\pi^- \\pi^0$. Based on the parameters obtained we predict the slope parameter for the neutral channel to be $\\alpha=-0.022\\pm 0.004$. Through matching to next-to-leading order chiral perturbation theory we estimate the quark mass double ratio to be $Q=21.4 \\pm 0.4$.

  16. Three-body Final State Interaction in η→3π

    DOE PAGESBeta

    Guo, Peng; Danilkin, Igor V.; Schott, Diane; Fernández-Ramírez, C.; Mathieu, V.; Szczepaniak, Adam P.

    2015-09-11

    We present an unitary dispersive model for themore » $$\\eta \\to 3 \\pi$$ decay process based upon the Khuri-Treiman equations which are solved by means of the Pasquier inversion method. The description of the hadronic final-state interactions for the $$\\eta \\to 3\\pi$$ decay is essential to reproduce the available data and to understand the existing discrepancies between Dalitz plot parameters from experiment and chiral perturbation theory. Our approach incorporates substraction constants that are fixed by fitting the recent high-statistics WASA-at-COSY data for $$\\eta \\to \\pi^+ \\pi^- \\pi^0$$. Based on the parameters obtained we predict the slope parameter for the neutral channel to be $$\\alpha=-0.022\\pm 0.004$$. Through matching to next-to-leading order chiral perturbation theory we estimate the quark mass double ratio to be $$Q=21.4 \\pm 0.4$$.« less

  17. The UV Scattering Halo of the Central Source Associated with Eta Carinae

    NASA Technical Reports Server (NTRS)

    Hillier, D. J.; Davidson, K.; Gull, T. R.; Humphreys, R. M.; Iping, R.; Sonneborn, G.

    2004-01-01

    Eta Carinae is one of the most massive and luminous stars within our galaxy. It consists of a compact central source which suffers circumstellar and interstellar extinction, local dense knots which emit strong narrow nebular-like emission lines, and an outer dusty nebula called the Homunculus. The optical spectrum of the central star, first observed directly and without obvious nebular contamination by the HST, can be modeled successfully using a hot star with a radius (at the wind sonic point) of 60\\,R\\odot. The central star is losing mass, via a dense stellar wind, at the prodigious rate of 10(exp -3)\\,M\\odot/yr. Its effective temperature is low (< 10,000\\,K), and is determined entirely by the wind properties. Until now the UV spectrum has not been explained. We show that HST UV spectrum, and the FUSE FUV spectrum, can both be understood using the same underlying model that explains the optical spectrum. To do so, however, it is necessary to take into account the occultation of the central source by dust. It is also important to realize that in the UV, the HST is partially resolving the central source. Due to strong mass loss, the wind is optically thick in UV resonance lines even at large radii. The UV resonance lines are responsible for the UV halo seen around Eta Carinae, and provide a partial explanation of why Eta Carinae can even be seen at UV wavelengths.

  18. Structural Basis for Error-free Replication of Oxidatively Damaged DNA by Yeast DNA Polymerase eta

    SciTech Connect

    T Silverstein; R Jain; R Johnson; L Prakash; S Prakash; A Aggarwal

    2011-12-31

    7,8-dihydro-8-oxoguanine (8-oxoG) adducts are formed frequently by the attack of oxygen-free radicals on DNA. They are among the most mutagenic lesions in cells because of their dual coding potential, where, in addition to normal base-pairing of 8-oxoG(anti) with dCTP, 8-oxoG in the syn conformation can base pair with dATP, causing G to T transversions. We provide here for the first time a structural basis for the error-free replication of 8-oxoG lesions by yeast DNA polymerase {eta} (Pol{eta}). We show that the open active site cleft of Pol{eta} can accommodate an 8-oxoG lesion in the anti conformation with only minimal changes to the polymerase and the bound DNA: at both the insertion and post-insertion steps of lesion bypass. Importantly, the active site geometry remains the same as in the undamaged complex and provides a basis for the ability of Pol to prevent the mutagenic replication of 8-oxoG lesions in cells.

  19. Nucleotide sequences of immunoglobulin eta genes of chimpanzee and orangutan: DNA molecular clock and hominoid evolution

    SciTech Connect

    Sakoyama, Y.; Hong, K.J.; Byun, S.M.; Hisajima, H.; Ueda, S.; Yaoita, Y.; Hayashida, H.; Miyata, T.; Honjo, T.

    1987-02-01

    To determine the phylogenetic relationships among hominoids and the dates of their divergence, the complete nucleotide sequences of the constant region of the immunoglobulin eta-chain (C/sub eta1/) genes from chimpanzee and orangutan have been determined. These sequences were compared with the human eta-chain constant-region sequence. A molecular clock (silent molecular clock), measured by the degree of sequence divergence at the synonymous (silent) positions of protein-encoding regions, was introduced for the present study. From the comparison of nucleotide sequences of ..cap alpha../sub 1/-antitrypsin and ..beta..- and delta-globulin genes between humans and Old World monkeys, the silent molecular clock was calibrated: the mean evolutionary rate of silent substitution was determined to be 1.56 x 10/sup -9/ substitutions per site per year. Using the silent molecular clock, the mean divergence dates of chimpanzee and orangutan from the human lineage were estimated as 6.4 +/- 2.6 million years and 17.3 +/- 4.5 million years, respectively. It was also shown that the evolutionary rate of primate genes is considerably slower than those of other mammalian genes.

  20. Giant factory caught contaminating the environment - Dust and molecules expelled by eta Carinae

    NASA Astrophysics Data System (ADS)

    Loinard, Laurent; Menten, Karl; Urquhart, James

    2014-04-01

    eta Carinae is one of the most massive stellar sources in the Milky Way and, in many respects, a remarkable astronomical object. It entered the hall of fame of astronomy in the mid 19th century when it underwent a major outburst, temporarily becoming the second brightest star at visible wavelengths in the entire sky. Known as the Great Eruption, this event led to the ejection of at least ten solar masses of material, now distributed in a bipolar nebula called the Homunculus. The material in the Homunculus provides us with a rare example of an ejecta that has not yet mixed with the ambient interstellar medium. Dust and molecules have formed out of this ejected material, and recent APEX and Herschel observations have shown that the chemical composition of the molecular component reflects the peculiar elemental abundances in the Homunuculus. Thus, eta Carinae provides us a unique opportunity to study directly the material injected into the interstellar medium by an evolved massive star, as well as the processes of dust and molecule formation occurring in situ in the ejecta. Here, we propose to constrain the spatial distribution and the physical conditions of the molecular components using sensitive H52 ATCA observations of the N2H+(1-0) line. These ATCA observations will constitute an important step toward a complete understanding of the origin of the molecular component around eta Carinae, that will have important repercussions for our comprehension of the latest phases of massive stellar evolution in general.

  1. Penetrating the Homunculus -- Near-Infrared Adaptive Optics Images of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Martin, John C.; Artigau, E.; Davidson, K.; Humphreys, R. M.; Chesneau, O.; Smith, N.

    2010-01-01

    We present the extraordinary near-infrared images of Eta Carinae obtained with the Near-Infrared Coronagraphic Camera (NICI) with adaptive optics on the Gemini South telescope just after Eta Car's 2009 spectroscopic event. The K-band continuum and continuum-subtracted narrow-band Br-gamma and H2 images show a three-winged pattern outlined by bright emitting dust in the innermost region of the ejecta around the central star. This intriguing pattern was first noticed by Chesneau et al. (2005) from earlier VLT/NaCO images and was named the "butterfly nebula.” In contrast the with the Br-gamma and H2 images, the [Fe II] image does not follow the outline of the "butterfly wings,” but instead shows a much broader, bipolar distribution traced to about 2 arcsec from the star. We suggest that the [Fe II] emission is tracing the "little Homunculus" previously observed only spectroscopically, and attributed to a bipolar outflow from Eta Car's second eruption in the 1890's. The nature of the "butterfly nebula" is debated and may be due to an ouflow or to an equatorial torus. Kinematic data is needed to measure or set limits on its expansion, age and orientation within the larger Homunculus. In this poster we also report the results of our measurements of the transverse motions of the knots and filaments that outline the "butterfly."

  2. Recent X-ray Variability of eta Carinae: the Quick Road to Recovery

    NASA Technical Reports Server (NTRS)

    Corcoran, M. Francis; Hamaguchi, K.; Pittard, J. M.; Russell, C. M. P.; Owocki, S. P.; Parkin, E. R.; Okazaki, A.

    2010-01-01

    We report continued monitoring of the superluminous binary system eta Car by the Proportional Counter Array on the Rossi X-ray Timing Observatory (RXTE) through the 2009 X-ray minimum. The RXTE campaign shows that the minimum began on 2009 January 16, consistent with the phasings of the two previous minima, and overall, the temporal behavior of the X-ray emission was similar to that observed by RXTE in the previous two cycles. However, important differences did occur. The 2-10 keV X-ray flux and X-ray hardness decreased in the 2.5-year interval leading up to the 2009 minimum compared to the previous cycle. Most intriguingly, the 2009 X-ray minimum was about one month shorter than either of the previous two minima. During the egress from the 2009 minimum the X-ray hardness increased markedly as it had during egress from the previous two minima, although the maximum X-ray hardness achieved was less than the maximum observed after the two previous recoveries. We suggest that the cycle-to-cycle variations, especially the unexpectedly early recovery from the 2009 X-ray minimum, might have been the result of a decline in eta Car's wind momentum flux produced by a drop in eta Car's mass loss rate or wind terminal velocity (or some combination), though if so the change in wind momentum flux required to match the X-ray variation is surprisingly large.

  3. Modeling of the H2 Fluorescence spectrum in Eta Car's ejecta

    NASA Astrophysics Data System (ADS)

    Nielsen, Krister

    2010-09-01

    Molecular hydrogen is the most abundant species in the interstellar medium and is observed in emission and absorption towards a wide range of astronomical objects. The presence of H2 is fundamental for the formation of complex molecules and dust. The H2 Lyman bands long-ward of 1200 A are usually not detected in a cold gaseous environment but, surprisingly, appears strongly in the spectrum of Eta Car's cold Homunculus. More than 800 H2 transitions have been identified in the mid-UV. The H2 absorption spectrum changes with Eta Car's 5.54 year spectroscopic period. These changes in H2 absorption strengths can provide information regarding the radiative flux variability caused by the companion star. We propose to use HST/STIS data recorded with the E140M grating between 1990.0 to 2004.3 to model the H2 spectrum and derive H2 column densities in the Eta Car Homunculus and how the column densities vary with phase. This will provide necessary input for accurate modeling of the Homunculus, which is an important step in the analysis of this unusual ejecta, and can be used for future studies of other massive stars.

  4. Global X-ray Spectral Variation of Eta Carinae through the 2003 X-ray Minimum

    NASA Technical Reports Server (NTRS)

    Hamaguchi, K.; Corcoran, M. F.; White, N. E.; Gull, T.; Damineli, A.; Davidson, K.

    2006-01-01

    We report on the results of the X-ray observing campaign of the massive, evolved star Eta Carinae in 2003 around its recent X-ray Minimum, mainly using data from the XMM-Newton observatory. These imaging observations show that the hard X-ray source associated with the Eta Carinae system does not completely disappear in any of the observations during the Minimum. The variation of the spectral shape revealed two emission components. One newly discovered component did not exhibit any variation on kilo-second to year-long timescales, in a combined analysis with earlier ASCA and ROSAT data, and might represent the collision of a high speed outflow from Eta Carinae with ambient gas clouds. The other emission component was strongly variable in flux but the temperature of the hottest plasma did not vary significantly at any orbital phase. Absorption to the hard emission, was about a factor of three larger than the absorption determined from the cutoff of the soft emission, and reached a maximum of approx.4 x 10(exp 23)/sq cm before the Minimum. The thermal Fe\\rm XXV emission line showed significant excesses on both the red and blue sides of the line outside the Minimum and exhibited a large redward excess during the Minimum. This variation in the line profile probably requires an abrupt change in ionization balance in the shocked gas.

  5. Multi-Wavelength Implications of the Companion Star in eta Carinae

    NASA Technical Reports Server (NTRS)

    Madura, Thomas I.; Gull, Theodore R.; Groh, Jose H.; Owocki, Stanley P.; Okazaki, Atsuo; Hillier, D. John; Russell, Christopher

    2012-01-01

    Eta-Carinae is considered to be a massive colliding wind binary system with a highly eccentric (e approximately 0.9), 5.54-yr orbit. However, the companion star continues to evade direct detection as the primary dwarfs its emission at most wavelengths. Using three-dimensional (3-D) SPH simulations of eta-Car's colliding winds and radiative transfer codes, we are able to compute synthetic observables across multiple wavebands for comparison to the observations. The models show that the presence of a companion star has a profound influence on the observed HST/STIS UV spectrum and H-alpha line profiles, as well as the ground-based photometric monitoring. Here, we focus on the Bore Hole effect, wherein the fast wind from the hot secondary star carves a cavity in the dense primary wind, allowing increased escape of radiation from the hotter/deeper layers of the primary's extended wind photosphere. The results have important implications for interpretations of eta-Car's observables at multiple wavelengths.

  6. Constraining the Extremely Hard X-ray Excess of Eta Carinae using XMM-Newton and NuSTAR

    NASA Astrophysics Data System (ADS)

    Sharma, Neetika; Hamaguchi, Kenji; Gull, Theodore R.; Corcoran, Michael F.; Madura, Thomas; Russell, Christopher Michael Post; Takahashi, Hiromitsu; Grefenstette, Brian; Yuasa, Tadayuki; Moffat, Anthony F. J.; Richardson, Noel; Groh, Jose H.; Pittard, Julian M.; Owocki, Stanley P.

    2016-06-01

    Eta Carinae (η Car), the most luminous (L∼106.7 L⊙), evolved, supermassive star (M≥100 M⊙) in our Galaxy, has been extensively studied over the entire range of wavelengths of the electromagnetic spectrum, and yet it remains to be intriguingly mysterious. η Car is a binary system with an orbital period of 2024 days (5.53 years). The collision of the slow (∼500 km s-1), dense winds from the primary star with the fast (∼3000 km s-1), thin winds from the companion, produces very hot plasma with temperatures of severals of millions of Kelvin via shock heating. Previously, the INTEGRAL and Suzaku observatories have suggested extremely high energy (15-100 keV) emission from η Car, which may arise from inverse Compton scattering of UV/optical photons by high-energy electrons accelerated in the wind colliding regions, or from the super hot plasma at the head-on collision. Recently, within a span of about 1.4 years (March 2014-July 2015), η Car was observed a total of 13 times with NuSTAR. The spectrum from the 2015 July observation, shows a hard X-ray excess above ∼ 17 keV, which can be constrained with a flat power-law (Γ∼0.5) or very hot bremsstrahlung (kT∼10 keV) component. This hard X-ray excess is significantly above the background level below 25 keV and therefore should not be instrumental. The light curves of the narrow sections of energy bands above 10 keV do not show significant variation. We discuss the origin of this extremely hard excess component from combined analysis of the XMM-Newton and NuSTAR data.

  7. Acceleration modules in linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Heng; Deng, Jian-Jun

    2014-05-01

    The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.

  8. {psi}'' Decays to charmless final states

    SciTech Connect

    Rosner, Jonathan L. . E-mail: rosner@hep.uchicago.edu

    2005-09-01

    The importance of measuring the non-DD-bar decays of the {psi}''={psi}(3770) resonance is discussed. These decays can shed light on a possible discrepancy between the total and DD-bar cross-sections at the {psi}'', and on a proposed mechanism for enhancement of penguin amplitudes in B meson decays through charm-anticharm annihilation. Measurements (including the {psi}'' line shape) in states of definite G-parity and in inclusive charmless final states such as {eta}'+X are found to be particularly important.

  9. Search for Planetary-mass Companions of the LHB Star eta Corvi

    NASA Astrophysics Data System (ADS)

    Marengo, Massimo; Lisse, Carey; Stapelfeldt, Karl; Hulsebus, Alan; Sitko, Michael

    2016-08-01

    The nearby sun-like star eta Corvi (F2V, d = 18 pc, age = 1.2 Gyr) has long been known to possess a bright, dusty Kuiper belt that has been recently resolved with Herschel/PACS. In addition to this structure, eta Corvi is one of the rare mature planetary systems to possess also an inner warm belt (~ 3 AU radius), located within the Terrestrial Habitable Zone (TLZ) of this star. Our characterization of this structure, based on Spitzer/IRS and NASA/IRTF SpeX spectral observations, reveals the signature of ice, organics and silicate dust in this warm belt. This supports the hypothesis that eta Corvi is undergoing a Late Heavy Bombardment (LHB), delivering life-bearing water- and organic-rich material from the Kuiper belt to the TLZ, at roughly the same age as the Solar System?s LHB. For the past four years we have monitored the brightness of eta Corvi?s warm belt with Spitzer/IRAC, finding that its infrared emission has been stable over a multi-year timescale. In 2012 we have also conducted a search for widely separated substellar-mass companions of this star, whose presence as been suggested as a possible trigger for the LHB currently undergoing in the system. This search has led to the identification of three sources with colors and magnitudes consistent with being late-T and Y dwarf companions of this star. We here propose to acquire a new deep roll-subtracted image of the system, 5 years after our first visit, to test for common proper motion of these candidate companions, and determine if any of this sources is physically associated with eta Corvi. A positive identification of a substellar-mass companions (one of which could be a 3-5 MJ planet at ~360 AU from the star) would be a significant step in understanding the processes leading to LHB-like events in a system analogous to the Solar System.

  10. Electron-transfer-catalyzed chelation of (Fe(. eta. sup 5 -C sub 5 R sub 5 )(. eta. sup 1 -SC(S)NMe sub 2 )(CO) sub 2 ) (R = H, Me) induced by oxidation

    SciTech Connect

    Verpeaux, J.N.; Amatore, C. ); Desbois, M.H.; Astruc, D. ); Madonik, A. )

    1990-03-01

    The chelation of the monodentate dithiocarbamate complexes (Fe({eta}{sup 5}-C{sub 5}R{sub 5})({eta}{sup 1}-dtc)(CO){sub 2}) (dtc = SC(S)NMe{sub 2}; R = H (1a), Me (1b)) to (Fe({eta}{sup 5}-C{sub 5}R{sub 5})({eta}{sup 2}-dtc)(CO)) (R = H (2a), Me (2b)) is catalyzed by (FeCp{sub 2}){sup +}X{sup {minus}} (X{sup {minus}} = PF{sub 6}{sup {minus}} (3a), BF{sup {minus}}{sub 4} (3b), SbCl{sup {minus}}{sub 6} (3c)) in THF. The mechanism involves the oxidation 1 + 3 {yields} 2{sup +}X{sup {minus}} + FeCp{sub 2} and the cross electron transfer (ET) 2{sup +}X{sup {minus}} + 1 {yields} 2+1{sup +}X{sup {minus}}. It shows that the deactivating step of 2b{sup +}X{sup {minus}} proceeds with a rate constant of ca. 10{sup {minus}1} s{sup {minus}1}. CV's, in the presence of PPh{sub 3}, show the existence of (FeCp{sup *}({eta}-dtc)(PPh{sub 3})){sup +/0} (4b{sup +}X{sup {minus}}/4b), and electrolysis of 1b in the presence of electrolyte gives a THF-soluble one-electron-oxidation complex, presumably (FeCp{sup *}({eta}{sup 2}-dtc)(PPh{sub 3})){sup +/0} (4b{sup +}X{sup {minus}}/4b), and electrolysis of 1b in the presence of electrolyte gives a THF-soluble one-electron-oxidation complex, presumably (FeCp{sup *}({eta}{sup 2}-dtc)(THF)){sup +}X{sup {minus}} (5b{sup +}X{sup {minus}}).

  11. Progress on plasma accelerators

    SciTech Connect

    Chen, P.

    1986-05-01

    Several plasma accelerator concepts are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wake Field Accelerator (PWFA). Various accelerator physics issues regarding these schemes are discussed, and numerical examples on laboratory scale experiments are given. The efficiency of plasma accelerators is then revealed with suggestions on improvements. Sources that cause emittance growth are discussed briefly.

  12. Elementary principles of linear accelerators

    NASA Astrophysics Data System (ADS)

    Loew, G. A.; Talman, R.

    1983-09-01

    A short chronology of important milestones in the field of linear accelerators is presented. Proton linacs are first discussed and elementary concepts such as transit time, shunt impedance, and Q are introduced. Critical issues such as phase stability and transverse forces are addressed. An elementary discussion of waveguide acclerating structures is also provided. Finally, electron accelerators addressed. Taking SLAC as an exmple, various topics are discussed such as structure design, choice of parameters, frequency optmization, beam current, emittance, bunch length and beam loading. Recent developments and future challenges are mentioned briefly.

  13. Presentation of points of general discussion and voting among the speakers of the European Thyroid Association-Cancer Research Network (ETA-CRN) meeting in Lisbon, 2009, entitled ”European comments to ATA medullary thyroid cancer guidelines”

    PubMed Central

    2013-01-01

    The main subjects of discussion, held online within the ETA-CRN board invited 16 expert-panelists are shown. The ad hoc emerged ETA-CRN panel of experts (EPE) first congratulated Professor Kloos and the ATA Taskforce for the extensive work on medullary thyroid cancer, and appreciated discussing the ATA guidelines during the ETA-CRN meeting. As it was not possible for all experts to visit the meeting, they enclosed their comments in the online ETA forum. The overall intention was to evaluate certain discrepancies between the ATA guidelines and were biased European clinical practice. All discussants were aware that the ATA guidelines had followed evidence based medicine rules; however, it was intended to reach an European consensus in this matter. The results of online voting among the EPE are shown. We received answers from nine experts. The particular ATA guidelines devoted to the management of MTC ranged in agreement in 0/9 to 4/9. This did not reflect the general, good assessment of the guidelines, as of votes a set of questions. The strongest discrepancies were found in assessment of the usefulness of pentagastrin (Peptavlon®) stimulated calcitonin secretion. The majority of the EPE (5/9) chose an option: “the increase of the basal Ct >100 ng/L means the substantial risk of MTC. However, there should also have been a recommendation for the grey zone 10-100 ng/L, where stimulation with pentagastrin is useful. The cut-off to perform stimulation test at ≤ 15-20 ng/L and values >100 ng/L means a significant suspicion of MTC”. Similarly, attention from the EPE was raised towards the surgical procedures in MTC, particularly the extent and indications for lymph node surgical intervention. Four questions were related to the indications to lymphadenectomy and extent of surgery. The equal number (4/8) of EPE agreed with the ATA R61 and half of the ETA-CRN panel of experts disagreed because the indications to lymphadenectomy (Lx) depended in their opinion on the

  14. New accelerators in high-energy physics

    SciTech Connect

    Blewett, J.P.

    1982-01-01

    First, I should like to mention a few new ideas that have appeared during the last few years in the accelerator field. A couple are of importance in the design of injectors, usually linear accelerators, for high-energy machines. Then I shall review some of the somewhat sensational accelerator projects, now in operation, under construction or just being proposed. Finally, I propose to mention a few applications of high-energy accelerators in fields other than high-energy physics. I realize that this is a digression from my title but I hope that you will find it interesting.

  15. NEW ACCELERATION METHODS

    SciTech Connect

    Sessler, A.M.

    1984-07-01

    But a glance at the Livingston chart, Fig. 1, of accelerator particle energy as a function of time shows that the energy has steadily, exponentially, increased. Equally significant is the fact that this increase is the envelope of diverse technologies. If one is to stay on, or even near, the Livingston curve in future years then new acceleration techniques need to be developed. What are the new acceleration methods? In these two lectures I would like to sketch some of these new ideas. I am well aware that they will probably not result in high energy accelerators within this or the next decade, but conversely, it is likely that these ideas will form the basis for the accelerators of the next century. Anyway, the ideas are stimulating and suffice to show that accelerator physicists are not just 'engineers', but genuine scientists deserving to be welcomed into the company of high energy physicists. I believe that outsiders will find this field surprisingly fertile and, certainly fun. To put it more personally, I very much enjoy working in this field and lecturing on it. There are a number of review articles which should be consulted for references to the original literature. In addition there are three books on the subject. Given this material, I feel free to not completely reference the material in the remainder of this article; consultation of the review articles and books will be adequate as an introduction to the literature for references abound (hundreds are given). At last, by way of introduction, I should like to quote from the end of Ref. 2 for I think the remarks made there are most germane. Remember that the talk was addressed to accelerator physicists: 'Finally, it is often said, I think by physicists who are not well-informed, that accelerator builders have used up their capital and now are bereft of ideas, and as a result, high energy physics will eventually--rather soon, in fact--come to a halt. After all, one can't build too many machines greater than

  16. DNA polymerase eta undergoes alternative splicing, protects against UV sensitivity and apoptosis, and suppresses Mre11-dependent recombination.

    PubMed

    Thakur, M; Wernick, M; Collins, C; Limoli, C L; Crowley, E; Cleaver, J E

    2001-11-01

    Polymerase eta (pol eta) is a low-fidelity DNA polymerase that is the product of the gene, POLH, associated with the human XP variant disorder in which there is an extremely high level of solar-induced skin carcinogenesis. The complete human genomic sequence spans about 40 kb containing 10 coding exons and a cDNA of 2.14 kb; exon I is untranslated and is 6 kb upstream from the first coding exon. Using bacterial artificial chromosomes (BACs), the gene was mapped to human chromosome band 6p21 and mouse band 17D. The gene is expressed in most tissues, except for very low or undetectable levels in peripheral lymphocytes, fetal spleen, and adult muscle; exon II, however, is frequently spliced out in normal cells and in almost half the transcripts in the testis and fetal liver. Expression of POLH in a multicopy episomal vector proved nonviable, suggesting that overexpression is toxic. Expression from chromosomally integrated linear copies using either an EF1-alpha or CMV promoter was functional, resulting in cell lines with low or high levels of pol eta protein, respectively. Point mutations in the center of the gene and in a C-terminal cysteine and deletion of exon II resulted in inactivation, but addition of a terminal 3 amino acid C-terminal tag, or an N- or C-terminal green fluorescent protein, had no effect on function. A low level of expression of pol eta eliminated hMre11 recombination and partially restored UV survival, but did not prevent UV-induced apoptosis, which required higher levels of expression. Polymerase eta is therefore involved in S-phase checkpoint and signal transduction pathways that lead to arrest in S, apoptosis, and recombination. In normal cells, the predominant mechanism of replication of UV damage involves pol eta-dependent bypass, and Mre11-dependent recombination that acts is a secondary, backup mechanism when cells are severely depleted of pol eta. PMID:11579462

  17. High-powered pulsed-ion-beam acceleration and transport

    SciTech Connect

    Humphries, S. Jr.; Lockner, T.R.

    1981-11-01

    The state of research on intense ion beam acceleration and transport is reviewed. The limitations imposed on ion beam transport by space charge effects and methods available for neutralization are summarized. The general problem of ion beam neutralization in regions free of applied electric fields is treated. The physics of acceleration gaps is described. Finally, experiments on multi-stage ion acceleration are summarized.

  18. Visions for the future of particle accelerators

    NASA Astrophysics Data System (ADS)

    Romaniuk, Ryszard S.

    2013-10-01

    The ambitions of accelerator based science, technology and applications far exceed the present accelerator possibilities. Accelerator science and technology is one of a key enablers of the developments in the particle physic, photon physics and also applications in medicine and industry. The paper presents a digest of the research results and visions for the future in the domain of accelerator science and technology in Europe, shown during the final fourth annual meeting of the EuCARD - European Coordination of Accelerator Research and Development. The conference concerns building of the research infrastructure, including advanced photonic and electronic systems for servicing large high energy physics experiments. There are debated a few basic groups of such systems like: measurement - control networks of large geometrical extent, multichannel systems for large amounts of metrological data acquisition, precision photonic networks of reference time, frequency and phase distribution. The main subject is however the vision for the future of particle accelerators and next generation light sources.

  19. Lectures in accelerator theory

    SciTech Connect

    Month, M

    1980-01-01

    Lecture I deals with the behavior of particles in the nonlinear field arising from the electromagnetic interaction of colliding beams. The case treated, that of counter-rotating proton beams crossing each other at a non-zero angle, has the simple feature that the force between the beam is one dimensional. In lecture II, an analysis of the development of traveling waves on particle beams is presented. The situation studied is that of a uniform beam current in a circular accelerator and the excitation for the coherent motion is induced by the resistivity of the vacuum chamber wall. Finally, in lecture III, a description of the current accumulation process used at the proton storage rings at CERN (The ISR) is given. Particle pulses of rather low average current are injected and stored along the length and width of the vacuum chamber. The efficiency is very high and large currents (over 40 amperes) have been achieved.

  20. Estimating ETAS: the effects of truncation, missing data, and model assumptions

    NASA Astrophysics Data System (ADS)

    Seif, Stefanie; Mignan, Arnaud; Zechar, Jeremy; Werner, Maximilian; Wiemer, Stefan

    2016-04-01

    The Epidemic-Type Aftershock Sequence (ETAS) model is widely used to describe the occurrence of earthquakes in space and time, but there has been little discussion of the limits of, and influences on, its estimation. What has been established is that ETAS parameter estimates are influenced by missing data (e.g., earthquakes are not reliably detected during lively aftershock sequences) and by simplifying assumptions (e.g., that aftershocks are isotropically distributed). In this article, we investigate the effect of truncation: how do parameter estimates depend on the cut-off magnitude, Mcut, above which parameters are estimated? We analyze catalogs from southern California and Italy and find that parameter variations as a function of Mcut are caused by (i) changing sample size (which affects e.g. Omori's cconstant) or (ii) an intrinsic dependence on Mcut (as Mcut increases, absolute productivity and background rate decrease). We also explore the influence of another form of truncation - the finite catalog length - that can bias estimators of the branching ratio. Being also a function of Omori's p-value, the true branching ratio is underestimated by 45% to 5% for 1.05< p <1.2. Finite sample size affects the variation of the branching ratio estimates. Moreover, we investigate the effect of missing aftershocks and find that the ETAS productivity parameters (α and K0) and the Omoris c-value are significantly changed only for low Mcut=2.5. We further find that conventional estimation errors for these parameters, inferred from simulations that do not account for aftershock incompleteness, are underestimated by, on average, a factor of six.

  1. A COMPANION AS THE CAUSE OF LATITUDE-DEPENDENT EFFECTS IN THE WIND OF ETA CARINAE

    SciTech Connect

    Groh, J. H.; Madura, T. I.; Weigelt, G.; Hillier, D. J.; Kruip, C. J. H.

    2012-11-01

    We analyze spatially resolved spectroscopic observations of the Eta Carinae binary system obtained with the Hubble Space Telescope/STIS. Eta Car is enshrouded by the dusty Homunculus nebula, which scatters light emitted by the central binary and provides a unique opportunity to study a massive binary system from different vantage points. We investigate the latitudinal and azimuthal dependence of H{alpha} line profiles caused by the presence of a wind-wind collision (WWC) cavity created by the companion star. Using two-dimensional radiative transfer models, we find that the wind cavity can qualitatively explain the observed line profiles around apastron. Regions of the Homunculus which scatter light that propagated through the WWC cavity show weaker or no H{alpha} absorption. Regions scattering light that propagated through a significant portion of the primary wind show stronger P Cygni absorption. Our models overestimate the H{alpha} absorption formed in the primary wind, which we attribute to photoionization by the companion, not presently included in the models. We can qualitatively explain the latitudinal changes that occur during periastron, shedding light on the nature of Eta Car's spectroscopic events. Our models support the idea that during the brief period of time around periastron when the primary wind flows unimpeded toward the observer, H{alpha} absorption occurs in directions toward the central object and Homunculus SE pole, but not toward equatorial regions close to the Weigelt blobs. We suggest that observed latitudinal and azimuthal variations are dominated by the companion star via the WWC cavity, rather than by rapid rotation of the primary star.

  2. Reconstructing the outburst history of Eta Carinae from WFPC2 proper motions

    NASA Astrophysics Data System (ADS)

    Smith, Nathan

    2011-10-01

    The HST archive contains several epochs of WFPC2 images of the nebula around Eta Carinae taken over a 15-year timespan, although only the earliest few years of data have been analyzed and published. The fact that all these images were taken with the same instrument, with the same pixel sampling and field distortion, makes them an invaluable resource for accurately measuring the expanding ejecta. So far, analysis of a subset of the data {with only a few year baseline} has shown that Eta Car's nebula was ejected around the time of the Great Eruption in the 1840s, but the full 15-yr dataset has much greater untapped potential. Historical data show multiple peaks in the light curve during the 1840s eruption, possibly the result of violent stellar collisions in the eccentric binary system. Proper motions with the full 15-yr dataset will definitively show if one of these is associated with the main mass ejection. Older material outside the main bipolar nebula traces previous major outbursts of the star with no recorded historical observations. We propose an ambitious reduction and analysis of the complete WFPC2 imaging dataset of Eta Car. These data can reconstruct its violent mass-loss history over the past several thousand years. This will constrain the behavior and timescale of eruptive mass loss in pre-SN evolution. The existence of several epochs over a long timespan will date older parts of the nebula that have not yet been measured, and can even measure the deceleration of the ejecta for the first time, essential for understanding their shaping and shock excitation during the nebula's continuing hydrodynamic evolution.

  3. Global Properties of the Ejecta Absorptions in the Spectrum of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Gull, T. R.; Vieira, G. L.; Danks, A. C.

    2002-12-01

    Between 2400A to 3160A, we have identified approximately 500 absorption line complexes, each with up to 20 velocity components. Lines of Fe I, Fe II, Ti II, V II, Ni II, Co II, Mn II, Mg I, Mg II and Na I have been identified. Surprisingly, most of the lines originate from energy levels significantly above the ground level. This is indicative of optical pumping from the Central Source. Line widths and population of various levels are non-thermal. The relative column densities change with velocity. For example, Fe II column densities for one transition arising from 0.1eV increase with ejecta velocity while Fe II column densities for another transition decreases with velocity. This may be due to softening of the ultraviolet radiation that pumps the various ions (neutrals) with velocity. If we assume that the distance of each system scales with distance from the Central Source, only a thirty percent change in distance is noted; yet the ratio of column densities for the Fe II examples given above changes by nearly thirty-fold. If the ejecta distance scales with distance from Eta Carinae, then it is likely that this ejecta originated at nearly the same time. The geometry of the Homunculus has been determined to be a double-lobed structure tilted out of the plane of the sky. We interpret the ejecta as being in the wall of the Southwest lobe, and that this wall just happens to be in line of sight from Eta Carinae to the observer. As Eta Carinae enters into the upcoming minimum, we are already seeing some evidence for changes in column densities due to changes in ultraviolet fluxes. This is reinforced by IUE observations that we have recently re-analyzed with respect to the 5.52 year (2020+/-10 days) spectroscopic period. Observations were done through STScI and funding was through the STIS GTO resources.

  4. Global Properties of the Ejecta Absorptions in the Spectrum of Eta Carinae

    NASA Technical Reports Server (NTRS)

    Gull, T. R.; Vieira, G.; Danks, A.

    2003-01-01

    Between 2400A to 3160A, we have identified approximately 500 absorption line complexes, each with up to 20 velocity components. Lines of Fe I, Fe II, Ti II, V II, Ni II, Co II, Mn II, Mg I, Mg II and Na I have been identified. Surprisingly, most of the lines originate from energy levels significantly above the ground level. This is indcative of optical pumping from the Central Source. Line widths and population of various levels are non-thermal. The relative column densities change with velocity. For example, Fe 11 column densities for one transition arising from approx. 0.l ev increase with ejecta velocity while Fe 11 column densities for another transition decreases with velocity. This may be due to softening of the ultraviolet radiation that pumps the various ions (neutrals) with velocity. If we assume that the distance of each system scales with distance from the Central Source, only a thirty percent change in distance is noted; yet the ratio of column densities for the Fe I1 examples given above changes by nearly thirty-fold. If the ejecta distance scales with distance from Eta Carinae, then it is likely that this ejecta originated at nearly the same time. The geometry of the Homunculus has been determined to be a double-lobed structure tilted out of the plane of the sky. We interpret the ejecta as being in the wall of the Southwest lobe, and that this wall just happens to be in line of sight from Eta Carinae to the observer. As Eta Carinae enters into the upcoming minimum, we are already seeing some evidence for changes in column densities due to changes in ultraviolet fluxes. This is reinforced by IUE observations that we have recently re-analyzed with respect to the 5.52 year (2020 +/- 10 days) spectroscopic period. Observations were done through STScI and funding was through the STIS GTO resources.

  5. A Companion as the Cause of Latitude-dependent Effects in the Wind of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Groh, J. H.; Madura, T. I.; Hillier, D. J.; Kruip, C. J. H.; Weigelt, G.

    2012-11-01

    We analyze spatially resolved spectroscopic observations of the Eta Carinae binary system obtained with the Hubble Space Telescope/STIS. Eta Car is enshrouded by the dusty Homunculus nebula, which scatters light emitted by the central binary and provides a unique opportunity to study a massive binary system from different vantage points. We investigate the latitudinal and azimuthal dependence of Hα line profiles caused by the presence of a wind-wind collision (WWC) cavity created by the companion star. Using two-dimensional radiative transfer models, we find that the wind cavity can qualitatively explain the observed line profiles around apastron. Regions of the Homunculus which scatter light that propagated through the WWC cavity show weaker or no Hα absorption. Regions scattering light that propagated through a significant portion of the primary wind show stronger P Cygni absorption. Our models overestimate the Hα absorption formed in the primary wind, which we attribute to photoionization by the companion, not presently included in the models. We can qualitatively explain the latitudinal changes that occur during periastron, shedding light on the nature of Eta Car's spectroscopic events. Our models support the idea that during the brief period of time around periastron when the primary wind flows unimpeded toward the observer, Hα absorption occurs in directions toward the central object and Homunculus SE pole, but not toward equatorial regions close to the Weigelt blobs. We suggest that observed latitudinal and azimuthal variations are dominated by the companion star via the WWC cavity, rather than by rapid rotation of the primary star. Based on observations made with HST/STIS.

  6. Search for the charge-conjugation-forbidden decay {omega}{yields}{eta}{pi}{sup 0}

    SciTech Connect

    Starostin, A.; Nefkens, B. M. K.; Brudvik, J.; Prakhov, S.; Suarez, I. M.; Ahrens, J.; Arends, H. J.; Bartolome, P. A.; Heid, E.; Jahn, O.; Martinez, M.; Ostrick, M.; Rost, M.; Thomas, A.; Annand, J. R. M.; Livingston, K.; MacGregor, I. J. D.; McGeorge, J. C.; McNicoll, E. F.; Robinson, J.

    2009-06-15

    A new upper limit of 2.3x10{sup -4} on the branching ratio of the decay {omega}{yields}{eta}{pi}{sup 0} has been obtained using the Crystal Ball multiphoton spectrometer at the Mainz Microtron MAMI. This decay is forbidden by charge-conjugation invariance of the strong and electromagnetic interactions. We have also obtained the upper limit of 2.3x10{sup -4} for the forbidden decay {omega}{yields}3{pi}{sup 0} and the upper limit of 2.4x10{sup -4} for {omega}{yields}2{pi}{sup 0}.

  7. Reaction {gamma}p {sup {yields}} {eta}' (958) p and polarization of recoil protons

    SciTech Connect

    Tryasuchev, V. A.

    2006-02-15

    On the basis of the isobar model extended by including the t-channel, the cross sections for and single-polarization features of the reaction {gamma}p {sup {yields}} {eta}'p are calculated for incident-photon energies up to 5 GeV, two poorly studied resonances, S{sub 11}(1978) and P{sub 13}(2080), being taken into account in this calculation. In order to reduce the ambiguities in the choice of resonances and their parameters that make it possible to reproduce the experimental differential cross sections, it is proposed to measure the polarization of recoil protons in the reaction being considered.

  8. Time-dependent CP-violation Parameters in B0 to eta' K0 Decay

    SciTech Connect

    Ulmer, K

    2006-09-26

    The authors present measurements of time-dependent CP-violation asymmetries for the decays B{sup 0} {yields} {eta}'K{sup 0}. The data sample corresponds to 347 million B{bar B} pairs produced by e{sup +}e{sup -} annihilation at the {Upsilon}(4S) resonance in the PEP-II collider, and collected with the BABAR detector. The preliminary results are S = 0.55 {+-} 0.11 {+-} 0.02, and C = -0.015 {+-} 0.07 {+-} 0.03, where the first error quoted is statistical, the second systematic.

  9. Observation of CP violation in B --> eta'K0 decays.

    PubMed

    Aubert, B; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lopes Pegna, D; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Cheng, C H; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Lee, C L; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Vazquez, W Panduro; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Clarke, C K; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Potter, C T; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Tehrani, F Safai; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Ricciardi, S; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Legendre, M; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Mellado, B; Mihalyi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2007-01-19

    We present measurements of the time-dependent CP-violation parameters S and C in B(0) --> eta(')K(0) decays. The data sample corresponds to 384 x 10(6) BB pairs produced by e(+)e(-) annihilation at the Upsilon(4S). The results are S=0.58+/-0.10+/-0.03 and C=-0.16+/-0.07+/-0.03. We observe mixing-induced CP violation with a significance of 5.5 standard deviations in this b --> s penguin dominated mode. PMID:17358676

  10. VizieR Online Data Catalog: Long-term spectroscopy of eta Carinae (Damineli+ 1998)

    NASA Astrophysics Data System (ADS)

    Damineli, A.; Stahl, O.; Kaufer, A.; Wolf, B.; Quast, G.; Lopes, D. F.

    1998-06-01

    This Table contains parameters of 655 spectral features in the spectrum of eta Carinae, in the wavelength region 3850-11000 Angstrom. The narrow and broad line components were measured separately, for the spectrum in high excitation state (year 1995) and during the "spectroscopic event" of June/1992. The spectra were collected at ESO (Chile) and LNA (Brazil) at high resolution. Several spectral lines of Fe II, [Fe II], [Fe III], [N II] ands Ca II are identifyed for the first time in the spectrum of this star. Line variability between high and low excitation states is characterized in an objective way (parameter var in the last column). (1 data file).

  11. The Little Homunculus of Eta Carinae: Ejection Date, Gas Temperature and Reddening Values

    NASA Technical Reports Server (NTRS)

    Ishibashi, K.; Davidson, K.; Gull, T. R.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    HST/STIS spectral monitoring of Eta Carinae and its ejecta reveals the presence of a relatively small bipolar structure inside the central regions of the familiar Homunculus lobes. Astrometric analysis shows that the Little Homunculus was most likely ejected during the 1890 event. Here we employ a simple plasma analysis on the ejecta: (1) identify the forbidden [Fe II] lines, and (2) use them with a Boltzmann distribution to estimate a locus in "gas temperature" -versus- "Reddening" parameter space. Our preliminary result shows that gas temperature of the Little Homunculus may be around 5000 K with reddening E(B-V) approx. = 0.5 of a standard interstellar reddening is valid.

  12. Simulating the Homunculus Nebula of Eta Carinae with an Innovative Multi-mass SPH Technique

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, Benedict J. R.; Podsiadlowski, P.

    2010-01-01

    We present a multi-mass, mixed resolution SPH technique which allows greatly reduced particle number while obtaining high resolution in lower density areas. Two sets of SPH particles are used - high mass for high density regions, low mass for low density regions. Hydrodynamic interaction between the sets is performed with the use of 'buffer' or tracer particles for each set. This technique has many applications in high density contrast simulations such as common envelope spin-up and low mass loss winds and mass transfer in binaries. We use this technique to test a common envelope ejection origin for the Homunculus nebula around Eta Carinae.

  13. Eta Carinae: What HST/STIS tells us in the UV

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Nielsen, Krister E.; Kober, Gladys V.

    2007-07-01

    High spectral and high spatial resolutions are combined in HST/STIS to reveal the neutral and ionic material in the Homunculus, ejecta of Eta Carinae. The Hubble Space Telescope`s (HST) high spatial resolution combined with the spectral resolution of Space Telescope Imaging Spectrograph (STIS) is revealing many hidden answers to questions about the character of η Car. We are examining spatially-resolved spectra recorded from 1998.0 to 2004.3 that show major changes in the stellar and nebular spectra, tracking the 2024-day period first noted in the He I λ10830 stellar line profile.

  14. Evaluation of the 29-km Eta Model. Part 1; Objective Verification at Three Selected Stations

    NASA Technical Reports Server (NTRS)

    Nutter, Paul A.; Manobianco, John; Merceret, Francis J. (Technical Monitor)

    1998-01-01

    This paper describes an objective verification of the National Centers for Environmental Prediction (NCEP) 29-km eta model from May 1996 through January 1998. The evaluation was designed to assess the model's surface and upper-air point forecast accuracy at three selected locations during separate warm (May - August) and cool (October - January) season periods. In order to enhance sample sizes available for statistical calculations, the objective verification includes two consecutive warm and cool season periods. Systematic model deficiencies comprise the larger portion of the total error in most of the surface forecast variables that were evaluated. The error characteristics for both surface and upper-air forecasts vary widely by parameter, season, and station location. At upper levels, a few characteristic biases are identified. Overall however, the upper-level errors are more nonsystematic in nature and could be explained partly by observational measurement uncertainty. With a few exceptions, the upper-air results also indicate that 24-h model error growth is not statistically significant. In February and August 1997, NCEP implemented upgrades to the eta model's physical parameterizations that were designed to change some of the model's error characteristics near the surface. The results shown in this paper indicate that these upgrades led to identifiable and statistically significant changes in forecast accuracy for selected surface parameters. While some of the changes were expected, others were not consistent with the intent of the model updates and further emphasize the need for ongoing sensitivity studies and localized statistical verification efforts. Objective verification of point forecasts is a stringent measure of model performance, but when used alone, is not enough to quantify the overall value that model guidance may add to the forecast process. Therefore, results from a subjective verification of the meso-eta model over the Florida peninsula are

  15. Laser driven ion accelerator

    DOEpatents

    Tajima, Toshiki

    2006-04-18

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  16. Laser driven ion accelerator

    DOEpatents

    Tajima, Toshiki

    2005-06-14

    A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

  17. Observation of a backward peak in the gamma d ---> pi0 d cross- section near the eta threshold

    SciTech Connect

    Yordanka Ilieva; Barry Berman; Alexander Kudryavtsev; I.I. Strakovsky; V.E. Tarasov; Moscov Amaryan; Pawel Ambrozewicz; Marco Anghinolfi; G. Asryan; Harutyun Avakian; Hovhannes Baghdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; V. Batourine; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Matthew Bellis; Nawal Benmouna; Angela Biselli; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Volker Crede; R. De Masi; Enzo De Sanctis; Raffaella De Vita; Pavel Degtiarenko; Alexandre Deur; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Kawtar Hafidi; Rafael Hakobyan; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde; Charles Hyde-Wright; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Mikhail Kossov; Zebulun Krahn; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Kenneth Livingston; Haiyun Lu; Marion MacCormick; Nikolai Markov; Bryan McKinnon; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; M. Moteabbed; E. Munevar; Gordon Mutchler; Pawel Nadel-Turonski; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; K. Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Oleg Pogorelko; S. Pozdniakov; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; David Tedeschi; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

    2007-05-14

    High-quality cross sections for the reaction gamma+d->pi^0+d have been measured using the CLAS at Jefferson Lab over a wide energy range near and above the eta-meson photoproduction threshold. At backward c.m. angles for the outgoing pions, we observe a resonance-like structure near E_gamma=700 MeV. Our model analysis shows that it can be explained by eta excitation in the intermediate state. The effect is the result of the contribution of the N(1535)S_11 resonance to the amplitudes of the subprocesses occurring between the two nucleons and of a two-step process in which the excitation of an intermediate eta meson dominates.

  18. Probing light pseudoscalar, axial vector states through {eta}{sub b}{yields}{tau}{sup +}{tau}{sup -}

    SciTech Connect

    Rashed, Ahmed; Duraisamy, Murugeswaran; Datta, Alakabha

    2010-09-01

    In this paper, we explore the decay {eta}{sub b}{yields}{tau}{sup +}{tau}{sup -} as a probe for a light pseudoscalar or a light axial vector state. We estimate the standard model branching ratio for this decay to be {approx}4x10{sup -9}. We show that considerably larger branching ratios, up to the present experimental limit of {approx}8%, are possible in models with a light pseudoscalar or a light axial vector state. As we do not include possible mixing effects between the light pseudoscalar and the {eta}{sub b}, our results should be reliable when the pseudoscalar mass is away from the {eta}{sub b} mass.

  19. Mosaic analysis of extended auricle1 (eta1) suggests that a two-way signaling pathway is involved in positioning the blade/sheath boundary in Zea mays.

    PubMed

    Osmont, Karen S; Sadeghian, Nasim; Freeling, Michael

    2006-07-01

    The maize leaf develops in a simple, stereotypical manner; therefore, it serves as a basic model to understand the processes involved in forming developmental boundaries. extended auricle1 (eta1) is a pleiotropic maize mutant that affects proximodistal leaf development. Mutant eta1 individuals display basipetal displacement of the blade/sheath boundary and the boundary between auricle and blade is not clearly delineated, leading to an undulating auricle. SEM analysis shows that eta1 is required for proper placement of the blade/sheath boundary on the adaxial leaf surface. Examination of vascular and cellular organization indicates that eta1 affects not only placement of the blade/sheath boundary, but also differentiation of cell types within the blade/sheath boundary. Genetic mosaic analysis was used to determine the effect of eta1 mutant tissue on wild-type leaf development and to resolve the site and timing of the Eta1+ gene product. Interestingly, sectors of eta1 tissue affect the placement of the blade/sheath boundary even in wild-type tissue. These results suggest that a two-way signaling pathway may be involved in the positioning of the blade/sheath boundary. Based on these data, we propose a model for Eta1+ function in the maize leaf. PMID:16684518

  20. Eta Carinae's change of state: First new HST/NUV data since 2010, and the first new FUV since 2004

    NASA Astrophysics Data System (ADS)

    Martin, John C.; Mehner, A.; Ishibashi, K.; Davidson, K.; Humphreys, R. M.

    2014-01-01

    During the past 15 years Eta Carinae has exhibited a critical phase in its recovery from the 19th century "Great Eruption." Dramatic changes in the ultraviolet brightness and spectrum between 1998 and 2010 indicated a surprisingly rapid increase in the UV flux of the central star and then a corresponding decrease in its mass-loss rate. We report the first UV photometry and spectra of Eta Carinae since 2010 and the first far-UV spectra in almost 10 years, obtained with the Hubble Space Telescope in September and November 2013. These measure the long-term secular changes prior to the onset of the anticipated spectroscopic event in August 2014.

  1. Atmospheric response to a realistic coastal polynya in Terra Nova Bay (Antarctica) simulated by ETA model.

    NASA Astrophysics Data System (ADS)

    Morelli, S.; Casini, G.; Parmiggiani, F.

    2009-04-01

    Coastal polynyas are areas of open water (and/or very thin ice) which form adjacent to coasts or blocking feature in polar regions during the wintertime, when the sea water is expected to be ice covered. They are thought to be maintained by strong offshore winds blowing over these area and/or by ocean currents. Sea ice is removed as it forms and drifted offshore. In polynya areas a direct contact is established between the relatively warm sea water and the cold, dry atmosphere. As a consequence, the physical characteristics of the atmospheric boundary layer change. The work presented here concerns a real polynya event in the region of Terra Nova Bay (TNB), Antarctica, where a recurring coastal polynya occurs nearby the Italian Antarctic Base. The aim is the study of atmospheric response to the presence of a open water area of realistic size by three-dimensional numerical simulations. Atmospheric numerical modelling is a fundamental tool for the study of air - polynya interactions in the remote polar regions, where observational data are difficult. The numerical model used for the simulations is a recent version of ETA model (Mesinger et al., 2006), with the addition of a piecewise linear advection for the wind field. ECMWF and NCEP data provided the initial and boundary conditions. A previous version of the model had already been successfully used in the Antarctic area (De Carolis et al, 2006, Casini and Morelli, 2007). As a first step to analyze the polynya event, numerical simulation was performed for the period from 12 to 17 July 2006 in order to study the development of the katabatic wind (Morelli and Casini, 2008; Morelli, 2008). Daily satellite images, concerning the period, display that a sea ice free area formed on 15 and 16 July, reaching its maximum extension of about 4000 km2 on 16 July (Morelli et al.,2007). In order to gain insight on the atmospheric response to open water area within a sea ice field, ETA model runs were carried out from 15 to 17 July

  2. X-ray Monitoring of eta Carinae: Variations on a Theme

    NASA Technical Reports Server (NTRS)

    Corcoran, M. F.

    2004-01-01

    We present monitoring observations by the Rossi X-ray Timing Explorer of the 2-10 keV X-ray emission from the supermassive star eta Carinae from 1996 through late 2003. These data cover more than one of the stellar variability cycles in temporal detail and include especially detailed monitoring through two X-ray minima. We compare the current X-ray minimum which began on June 29, 2003 to the previous X-ray minimum which began on December 15, 1997, and refine the X-ray period to 2024 days. We examine the variations in the X-ray spectrum with phase and with time, and also refine our understanding of the X-ray peaks which have a quasi-period of 84 days, with significant variation. Cycle-to-cycle differences are seen in the level of X-ray intensity and in the detailed variations of the X-ray flux on the rise to maximum just prior to the X-ray minimum. Despite these differences the similarities between the decline to minimum, the duration of the minimum, and correlated variations of the X-ray flux and other measures throughout the electromagnetic spectrum leave little doubt that that the X-ray variation is strictly periodic and produced by orbital motion as the wind from eta Carinae collides with the wind of an otherwise unseen companion.

  3. Eclipse and Collapse of the Colliding Wind X-ray Emission from Eta Carinae

    NASA Technical Reports Server (NTRS)

    Hamaguchi, Kenji; Corcoran, Michael F.

    2012-01-01

    X-ray emission from the massive stellar binary system, Eta Carinae, drops strongly around periastron passage; the event is called the X-ray minimum. We launched a focused observing campaign in early 2009 to understand the mechanism of causing the X-ray minimum. During the campaign, hard X-ray emission (<10 keV) from Eta Carinae declined as in the previous minimum, though it recovered a month earlier. Extremely hard X-ray emission between 15-25 keV, closely monitored for the first time with the Suzaku HXD/PIN, decreased similarly to the hard X-rays, but it reached minimum only after hard X-ray emission from the star had already began to recover. This indicates that the X-ray minimum is produced by two composite mechanisms: the thick primary wind first obscured the hard, 2-10 keV thermal X-ray emission from the wind-wind collision (WWC) plasma; the WWC activity then decays as the two stars reach periastron.

  4. Determining Cloud Parameters with the Curve-Of-Growth: Application Eta Car

    NASA Technical Reports Server (NTRS)

    Vieira, G. L.; Gull, T. R.; Bruhweiler, F.; Nielsen, K. E.; Verner, E. M.

    2004-01-01

    We have investigated the NUV part of the Eta Car spectrum, using data with high spatial and high spectral resolving power obtained with the HST/STIS under the Treasury Program. The NUV spectrum of Eta Car Shows a great contribution of absorption features from neutral and singly ionized elements along the line-of-sight. A large number of velocity systems have been observed. The two most prominent, with Doppler shifts corresponding to -146 and -513 km/s respectively, are shown to be useful for investigations of the gaseous environments responsible for the absorption. The -146 and the -513 km/s velocity systems display different characteristics regarding the ionization state and spectral line width, which suggest that they originate at different distances from the central object. We have investigated the absorption structures before the spectroscopic minimum, occurring during the summer of 2003, with a standard curve-of-growth. We have independently derived the column density and the b-value for the Fe II (-146 km/s) and Ti II (-513 km/s) velocity systems. The excitation temperature has been determined for the -146 km/s velocity system using the photo-ionization code \\textsc(cloudy). The -146 km/s velocity structure shows noticeable variation over the spectroscopic minimum. The sudden appearance and disappearance of Ti II and V II are astonishing. We have made an attempt to analyze these variations with the curve-of-growth method and will present preliminary results.

  5. Localization of endothelin ETA and ETB receptor-mediated constriction in the renal microcirculation of rats.

    PubMed Central

    Endlich, K; Hoffend, J; Steinhausen, M

    1996-01-01

    1. The aim of the study was to visualize endothelin-1 (ET-1)-mediated constriction in renal vessels of cortical and juxtamedullary glomeruli in the split hydronephrotic rat kidney in vivo and to functionally characterize the ET receptor subtypes involved. 2. ET-1 (10(-9) M) constricted preglomerular vessels (by 6-18%) and efferent arterioles (by 11-13%), and decreased glomerular blood flow (GBF, by 55%) of cortical and juxtamedullary glomeruli. 3. The ETA antagonist BQ-123 (10(-6) M), as well as the ETB antagonist BQ-788 (2 x 10(-7) M) and IRL 1038 (10(-6) M), shifted the concentration-response curve of GBF for ET-1 to the right by one order of magnitude. While BQ-123 antagonized ET-1 constriction only in preglomerular vessels, BQ-788 and IRL 1038 were effective both in preglomerular vessels and efferent arterioles. 4. The ETB agonist IRL 1620 (10(-8) M) reduced GBF by 50% and constricted efferent arterioles (by 20-33%) about two times more than preglomerular vessels (by 6-14%). 5. Our results suggest that in renal cortical and juxtamedullary vessels of rats, ET-1-induced preglomerular vasoconstriction is mediated by ETA and ETB receptors, while efferent vasoconstriction is predominantly mediated by ETB receptors, which might have important consequences for the regulation of glomerular filtration pressure by ET. PMID:8951723

  6. Eta Carinae: A Box of Puzzles...Some Solved, Others Await

    NASA Technical Reports Server (NTRS)

    Gull, Theodore

    2010-01-01

    In the l840's, Eta Carinae brightened to rival Sirius, then faded. Today we see a marginally naked-eye binary with an expanding, very dusty bipolar Homunculus. The energetics of the ejected mass (>l2 to 40 solar masses at 500-700 km/s plus outer bullets/strings up to 3000 km/s} approach that of a supernova. Extragalactic SN surveys detect near-supernovae thought to be like the Great Eruption of the 1840's. Eta Carinae presents an abundance of puzzles: rich in N, but 1/100th the solar C and O abundances; Ti, V, Sr, Sc persist in atomic states.... yet an abundance of molecules and dust exists in the Homunculus. How did molecules and dust form with low C and O? A near supernova occurred in the l840m, yet both binary companions, with total mass > 120 solar masses, survive in a very eccentric orbit. What is the near future of this system: a GRB? a SN? or just two WR stars that ultimately become two SNs? These and other puzzles will be presented

  7. Image of the Eta Carinae Nebula Taken by the High Energy Astronomy Observatory (HEAO)-2

    NASA Technical Reports Server (NTRS)

    1979-01-01

    This image is an x-ray view of Eta Carinae Nebula showing bright stars taken with the High Energy Astronomy Observatory (HEAO)-2/Einstein Observatory. The Eta Carinae Nebula is a large and complex cloud of gas, crisscrossed with dark lanes of dust, some 6,500 light years from Earth. Buried deep in this cloud are many bright young stars and a very peculiar variable star. The HEAO-2, the first imaging and largest x-ray telescope built to date, was capable of producing actual photographs of x-ray objects. Shortly after launch, the HEAO-2 was nicknamed the Einstein Observatory by its scientific experimenters in honor of the centernial of the birth of Albert Einstein, whose concepts of relativity and gravitation have influenced much of modern astrophysics, particularly x-ray astronomy. The HEAO-2, designed and developed by TRW, Inc. under the project management of the Marshall Space Flight Center, was launched aboard an Atlas/Centaur launch vehicle on November 13, 1978.

  8. The Line Profile Variations of eta Carinae Through the 2009.0 Spectroscopic Event

    NASA Astrophysics Data System (ADS)

    Richardson, Noel; Gies, D.; Henry, T.; Fernandez-Lajus, E.; Okazaki, A.

    2010-01-01

    We report on high resolution echelle spectroscopy of the 2009.0 spectroscopic event of eta Carinae that we collected via SMARTS observations using the CTIO 1.5 m telescope and echelle spectrograph. Our observations were made almost every night over a two month interval around the predicted minimum of eta Car. We observed a dramatic fading of the H-alpha line emission that reached a minimum six days after the X-ray minimum. About 15 days prior to the H-alpha flux minimum, the H-alpha profile exhibited the emergence of a broad, P Cygni type, absorption component (near a Doppler shift of -500 km/s and a narrow absorption component (near -144 km/s and probably associated with intervening gas from the Little Homunculus Nebula). We also observed the He I 5876, 6678, and 7065 lines. The line profile variations are similar to those observed during previous events, and the temporal variations are consistent with qualitative expectations about changes in the primary star's stellar wind that result from the wind - wind collision with a massive binary companion. This work was supported by the National Science Foundation under grant AST-0606861.

  9. Photometric and Kinematic Analysis of ACS/HRC Ultraviolet Images of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Rosen, Drew; Morse, J. A.

    2013-06-01

    We present an analysis of archival near-UV HST-ACS/HRC images of Eta Carina to search for spectrophotometric variations in, e.g., Mg II absorption/emission in inner regions of the Homunculus Nebula. Eta Carinae is a massive binary star system of approximately 150 solar masses, making it one of the most massive star systems that can be studied. The primary star appears to be approaching the end of its lifetime, and it is expected to go supernova (or hypernova) within the next million years, or possibly much sooner. The companion star, also apparently highly evolved, has a highly eccentric elliptical orbit with a period of 5.5 years that passes very close to, or even grazes, the photosphere of the larger primary star. Evidence suggests that periastron passage of the companion creates instabilities through the primary star that have resulted in the ejection of vast amounts of material in the Homunculus Nebulae, possibly at different epochs and in different directions.

  10. Systemic and renal effects of an ETA receptor subtype-specific antagonist in healthy subjects

    PubMed Central

    Schmetterer, Leopold; Dallinger, Susanne; Bobr, Barbara; Selenko, Nicole; Eichler, Hans-Georg; Wolzt, Michael

    1998-01-01

    Endothelins (ETs) might play a pathophysiological role in a variety of vascular diseases. The aim of the present study was to characterize the effects of BQ-123, a specific ETA receptor antagonist on systemic and renal haemodynamics in healthy subjects. This was done at baseline and during infusion of exogenous ET-1.The study was performed in a balanced, randomized, placebo-controlled, double blind 4 way cross-over design in 10 healthy male subjects. Subjects received co-infusions of ET-1 (2.5 ng kg−1 min−1 for 120 min) or placebo and BQ-123 (15 μg min−1 for 60 min and subsequently 60 μg min−1 for 60 min) or placebo. Renal plasma flow (RPF) and glomerular filtration rate (GFR) were assessed by the para-aminohippurate (PAH) and the inulin plasma clearance method, respectively.BQ-123 alone had no renal or systemic haemodynamic effect. ET-1 significantly reduced RPF (−24%, P<0.001) and GFR (−12%, P=0.034). These effects were abolished by co-infusion of either dose of BQ-123 (RPF: P=0.0012; GFR: P=0.020).BQ-123 reversed the renal haemodynamic effects induced by exogenous ET-1 in vivo. This indicates that vasoconstriction in the kidney provoked by ET-1 is predominantly mediated by the ETA receptor subtype. PMID:9692778

  11. THE H{alpha} VARIATIONS OF {eta} CARINAE DURING THE 2009.0 SPECTROSCOPIC EVENT

    SciTech Connect

    Richardson, N. D.; Gies, D. R.; Henry, T. J.; Fernandez-Lajus, E. E-mail: gies@chara.gsu.edu E-mail: eflajus@fcaglp.unlp.edu.ar

    2010-04-15

    We report on H{alpha} spectroscopy of the 2009.0 spectroscopic event of {eta} Carinae collected via SMARTS observations using the Cerro Tololo Interamerican Observatory 1.5 m telescope and echelle spectrograph. Our observations were made almost every night over a two-month interval around the predicted minimum of {eta} Car. We observed a significant fading of the line emission that reached a minimum 7 days after the X-ray minimum. About 17 days prior to the H{alpha} flux minimum, the H{alpha} profile exhibited the emergence of a broad, P Cygni type, absorption component (near a Doppler shift of -500 km s{sup -1}) and a narrow absorption component (near -144 km s{sup -1} and probably associated with intervening gas from the Little Homunculus Nebula). All these features were observed during the last event in 2003.5 and are probably related to the close periastron passage of the companion. We argue that these variations are consistent with qualitative expectations about changes in the primary star's stellar wind that result from the wind-wind collision with a massive binary companion and from atmospheric eclipses of the companion.

  12. High Resolution Temporal and Spectral Monitoring of Eta Carinae's X-Ray Emission the June Eclipse

    NASA Technical Reports Server (NTRS)

    Corcoran, M. F.; Hamaguchi, K.; Henley, D.; Pittard, J. M.; Gull, T. R.; Davidson, K.; Swank, J. H.; Petre, R.; Ishibashi, K.

    2004-01-01

    The supermassive and luminous star Eta Carinae undergoes strong X-ray variations every 5.5 years when its 2-10 keV X-ray emission brightens rapidly with wild fluctuations before dropping by a factor of 100 to a minimum lasting 3 months. The most recent X-ray "eclipse" began in June 2003 and during this time Eta Carinae was intensely observed throughout the electromagnetic spectrum. Here we report the first results of frequent monitoring of the 2-10 keV band X-ray emission by the Rossi X-ray Timing Explorer along wit high resolution X-ray spectra obtained with the transmission gratings on the Chandra X-ray Observatory. We compare these observations to those results obtained during the previous X-ray eclipse in 1998, and interpret the variations in the X-ray brightness, in the amount of absorption, in the X-ray emission measure and in the K-shell emission lines in terms of a colliding wind binary model.

  13. Measurement of the B{sup +}{yields}{omega}l{sup +}{nu} and B{sup +}{yields}{eta}l{sup +}{nu} branching fractions

    SciTech Connect

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G. S.; Battaglia, M.; Brown, D. N.; Cahn, R. N.

    2009-03-01

    We present a study of the charmless semileptonic B-meson decays B{sup +}{yields}{omega}l{sup +}{nu} and B{sup +}{yields}{eta}l{sup +}{nu}. The analysis is based on 3.83x10{sup 8} BB pairs recorded at the {upsilon}(4S) resonance with the BABAR detector. The {omega} mesons are reconstructed in the channel {omega}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0} and the {eta} mesons in the channels {eta}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup 0} and {eta}{yields}{gamma}{gamma}. We measure the branching fractions B(B{sup +}{yields}{omega}l{sup +}{nu})=(1.14{+-}0.16{sub stat}{+-}0.08{sub syst})x10{sup -4} and B(B{sup +}{yields}{eta}l{sup +}{nu})=(0.31{+-}0.06{sub stat}{+-}0.08{sub syst})x10{sup -4}.

  14. Common suppression pattern of eta and pi0 mesons at high transverse momentum in Au + Au collisions at square root S(NN) = 200 GeV.

    PubMed

    Adler, S S; Afanasiev, S; Aidala, C; Ajitanand, N N; Akiba, Y; Alexander, J; Amirikas, R; Aphecetche, L; Aronson, S H; Averbeck, R; Awes, T C; Azmoun, R; Babintsev, V; Baldisseri, A; Barish, K N; Barnes, P D; Bassalleck, B; Bathe, S; Batsouli, S; Baublis, V; Bazilevsky, A; Belikov, S; Berdnikov, Y; Bhagavatula, S; Boissevain, J G; Borel, H; Borenstein, S; Brooks, M L; Brown, D S; Bruner, N; Bucher, D; Buesching, H; Bumazhnov, V; Bunce, G; Burward-Hoy, J M; Butsyk, S; Camard, X; Chai, J-S; Chand, P; Chang, W C; Chernichenko, S; Chi, C Y; Chiba, J; Chiu, M; Choi, I J; Choi, J; Choudhury, R K; Chujo, T; Cianciolo, V; Cobigo, Y; Cole, B A; Constantin, P; d'Enterria, D; David, G; Delagrange, H; Denisov, A; Deshpande, A; Desmond, E J; Devismes, A; Dietzsch, O; Drapier, O; Drees, A; du Rietz, R; Durum, A; Dutta, D; Efremenko, Y V; Chenawi, K El; Enokizono, A; En'yo, H; Esumi, S; Ewell, L; Fields, D E; Fleuret, F; Fokin, S L; Fox, B D; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fung, S-Y; Garpman, S; Ghosh, T K; Glenn, A; Gogiberidze, G; Gonin, M; Gosset, J; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Perdekamp, M Grosse; Guryn, W; Gustafsson, H-A; Hachiya, T; Haggerty, J S; Hamagaki, H; Hansen, A G; Hartouni, E P; Harvey, M; Hayano, R; Hayashi, N; He, X; Heffner, M; Hemmick, T K; Heuser, J M; Hibino, M; Hiejima, H; Hill, J C; Holzmann, W; Homma, K; Hong, B; Hoover, A; Ichihara, T; Ikonnikov, V V; Imai, K; Isenhower, D; Ishihara, M; Issah, M; Isupov, A; Jacak, B V; Jang, W Y; Jeong, Y; Jia, J; Jinnouchi, O; Johnson, B M; Johnson, S C; Joo, K S; Jouan, D; Kametani, S; Kamihara, N; Kang, J H; Kapoor, S S; Katou, K; Kelly, S; Khachaturov, B; Khanzadeev, A; Kikuchi, J; Kim, D H; Kim, D J; Kim, D W; Kim, E; Kim, G-B; Kim, H J; Kistenev, E; Kiyomichi, A; Kiyoyama, K; Klein-Boesing, C; Kobayashi, H; Kochenda, L; Kochetkov, V; Koehler, D; Kohama, T; Kopytine, M; Kotchetkov, D; Kozlov, A; Kroon, P J; Kuberg, C H; Kurita, K; Kuroki, Y; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Ladygin, V; Lajoie, J G; Lebedev, A; Leckey, S; Lee, D M; Lee, S; Leitch, M J; Li, X H; Lim, H; Litvinenko, A; Liu, M X; Liu, Y; Maguire, C F; Makdisi, Y I; Malakhov, A; Manko, V I; Mao, Y; Martinez, G; Marx, M D; Masui, H; Matathias, F; Matsumoto, T; McGaughey, P L; Melnikov, E; Messer, F; Miake, Y; Milan, J; Miller, T E; Milov, A; Mioduszewski, S; Mischke, R E; Mishra, G C; Mitchell, J T; Mohanty, A K; Morrison, D P; Moss, J M; Mühlbacher, F; Mukhopadhyay, D; Muniruzzaman, M; Murata, J; Nagamiya, S; Nagle, J L; Nakamura, T; Nandi, B K; Nara, M; Newby, J; Nilsson, P; Nyanin, A S; Nystrand, J; O'Brien, E; Ogilvie, C A; Ohnishi, H; Ojha, I D; Okada, K; Ono, M; Onuchin, V; Oskarsson, A; Otterlund, I; Oyama, K; Ozawa, K; Pal, D; Palounek, A P T; Pantuev, V; Papavassiliou, V; Park, J; Parmar, A; Pate, S F; Peitzmann, T; Peng, J-C; Peresedov, V; Pinkenburg, C; Pisani, R P; Plasil, F; Purschke, M L; Purwar, A K; Rak, J; Ravinovich, I; Read, K F; Reuter, M; Reygers, K; Riabov, V; Riabov, Y; Roche, G; Romana, A; Rosati, M; Rosnet, P; Ryu, S S; Sadler, M E; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakai, M; Sakai, S; Samsonov, V; Sanfratello, L; Santo, R; Sato, H D; Sato, S; Sawada, S; Schutz, Y; Semenov, V; Seto, R; Shaw, M R; Shea, T K; Shibata, T-A; Shigaki, K; Shiina, T; Silva, C L; Silvermyr, D; Sim, K S; Singh, C P; Singh, V; Sivertz, M; Soldatov, A; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Staley, F; Stankus, P W; Stenlund, E; Stepanov, M; Ster, A; Stoll, S P; Sugitate, T; Sullivan, J P; Takagui, E M; Taketani, A; Tamai, M; Tanaka, K H; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarján, P; Tepe, J D; Thomas, T L; Tojo, J; Torii, H; Towell, R S; Tserruya, I; Tsuruoka, H; Tuli, S K; Tydesjö, H; Tyurin, N; van Hecke, H W; Velkovska, J; Velkovsky, M; Veszprémi, V; Villatte, L; Vinogradov, A A; Volkov, M A; Vznuzdaev, E; Wang, X R; Watanabe, Y; White, S N; Wohn, F K; Woody, C L; Xie, W; Yang, Y; Yanovich, A; Yokkaichi, S; Young, G R; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zhou, S J; Zolin, L

    2006-05-26

    Inclusive transverse momentum spectra of eta mesons have been measured within p(T) = 2-10 GeV/c at midrapidity by the PHENIX experiment in Au + Au collisions at square root S(NN) = 200 GeV. In central Au+Au the eta yields are significantly suppressed compared to peripheral Au + Au, d + Au, and p + p yields scaled by the corresponding number of nucleon-nucleon collisions. The magnitude, centrality, and p(T) dependence of the suppression is common, within errors, for eta and pi0. The ratio of eta to pi0 spectra at high p(T) amounts to 0.40 < R(eta/pi)0 < 0.48 for the three systems, in agreement with the world average measured in hadronic and nuclear reactions and, at large scaled momentum, in e+e- collisions. PMID:16803168

  15. Eta vs sigma, an update: Gallus-Klemp test, and 250 hPa wind skill compared to ECMWF in ensemble experiments

    NASA Astrophysics Data System (ADS)

    Mesinger, Fedor; Veljovic, Katarina

    2015-04-01

    In our presentation at the 2013 EGU Assembly experiments were reviewed comparing the Eta model results against those using the same code but switched to sigma. Using the eta, better precipitation scores, and more accurate placement of storms, stood out. Improvements with the eta were particularly noticeable over the lee slopes of the Rocky Mountains topography. A recent discovery of an omission in making the model's Smagorinsky-like horizontal diffusion aware of the sloping steps discretization enabled a replication of the Gallus and Klemp (Mon. Wea. Rev., 2000) test of flow over a bell-shaped mountain with a very high degree of resemblance to the one they obtained after addressing the flow-separation problem of the step-topography eta. Results were also discussed in the 2013 presentation of experiments in which 26 Eta ensemble members driven by an ECMWF 32-day ensemble mostly had better scores in placing strong 250 hPa winds than their driver members; and of a test of the impact of having 10 of these Eta members use sigma. While no obvious impact on 250 hPa wind scores stood out, a tendency was seen for more accurate tilt at an apparently crucial time of the 250 hPa trough of the eta compared to sigma members. To test the sensitivity to resolution and also to check on the robustness of this Eta vs ECMWF result to the choice of the period a 10-member Eta experiment was rerun for a more recent ECMWF ensemble, one initialized 4 October 2012, when its resolution was higher than of that used previously. The advantage of the Eta members more frequently than not is seen again, even though this time the resolution of the Eta during the first 10 days of the experiment was about the same as that of the driver ECMWF members. Rerunning the Eta ensemble with the code switched to sigma this time however an advantage of the Eta/eta over the Eta/sigma is seen, quite considerable during the early 2-6 day period of the experiment when a deep upper-air trough was moving across the

  16. The interacting winds of Eta Carinae: Observed forbidden line changes and the Forbidden Blue(-Shifted) Crab

    NASA Astrophysics Data System (ADS)

    Gull, Theodore R.; Madura, Thomas; Corcoran, Michael F.; Teodoro, Mairan; Richardson, Noel; Hamaguchi, Kenji; Groh, Jose H.; Hillier, Desmond John; Damineli, Augusto; Weigelt, Gerd

    2015-01-01

    The massive binary, Eta Carinae (EC), produces such massive winds that strong forbidden line emission of singly- and doubly-ionized iron traces wind-wind interactions from the current cycle plus fossil interactions from one, two and three 5.54-year cycles ago.With an eccentricity of >0.9, the >90 solar mass primary (EC-A) and >30 solar mass secondary (EC-B) approach to within 1.5 AU during periastron and recede to nearly 30 AU across apastron. The wind-wind structures move outward driven by the 420 km/s primary wind interacting with the ~3000 km/s secondary wind yielding partially-accelerated compressed primary wind shells that are excited by mid-UV from EC-A and in limited lines of sight, FUV from EC-B.These structures are spectroscopically and spatially resolved by HST's Space Telescope Imaging Spectrograph. At critical binary phases, we have mapped the central 2'x2' region in the light of [Fe III] and [Fe II] with spatial resolution of 0.12' and velocity resolution of 40 km/s.1) The bulk of forbidden emission originates from the large cavity northwest of EC and is due to ionization of massive ejecta from the 1840s and 1890s eruptions. The brightest clumps are the Weigelt Blobs C and D, but there are additionally multiple, fainter emission clumps. Weigelt B appears to have faded.2) Three concentric, red-shifted [FeII] arcs expand at ~470 km/s excited by mid-UV of EC-A.3) The structure of primarily blue-shifted [Fe III] emission resembles a Maryland Blue Crab. The claws appear at the early stages of the high-excitation recovery from the periastron passage, expand at radial velocities exceeding the primary wind terminal velocity, 420 km/s and fade as the binary system approaches periastron with the primary wind enveloping the FUV radiation from EC-B.4) All [Fe III] emission faded by late June 2014 and disappeared by August 2, 2014, the beginning of periastron passage.Comparisons to HST/STIS observations between 1998 to 2004.3 indicate long-term fading of [Fe II

  17. Single particle dynamics in circular accelerators

    SciTech Connect

    Ruth, R.D.

    1986-10-01

    The purpose of this paper is to introduce the reader to the theory associated with the transverse dynamics of single particle, in circular accelerators. The discussion begins with a review of Hamiltonian dynamics and canonical transformations. The case of a single particle in a circular accelerator is considered with a discussion of non-linear terms and chromaticity. The canonical perturbation theory is presented and nonlinear resonances are considered. Finally, the concept of renormalization and residue criterion are examined. (FI)

  18. Nondiffracting accelerating wave packets of Maxwell's equations.

    PubMed

    Kaminer, Ido; Bekenstein, Rivka; Nemirovsky, Jonathan; Segev, Mordechai

    2012-04-20

    We present the nondiffracting spatially accelerating solutions of the Maxwell equations. Such beams accelerate in a circular trajectory, thus generalizing the concept of Airy beams to the full domain of the wave equation. For both TE and TM polarizations, the beams exhibit shape-preserving bending which can have subwavelength features, and the Poynting vector of the main lobe displays a turn of more than 90°. We show that these accelerating beams are self-healing, analyze their properties, and find the new class of accelerating breathers: self-bending beams of periodically oscillating shapes. Finally, we emphasize that in their scalar form, these beams are the exact solutions for nondispersive accelerating wave packets of the most common wave equation describing time-harmonic waves. As such, this work has profound implications to many linear wave systems in nature, ranging from acoustic and elastic waves to surface waves in fluids and membranes. PMID:22680719

  19. The direction of acceleration

    NASA Astrophysics Data System (ADS)

    Wilhelm, Thomas; Burde, Jan-Philipp; Lück, Stephan

    2015-11-01

    Acceleration is a physical quantity that is difficult to understand and hence its complexity is often erroneously simplified. Many students think of acceleration as equivalent to velocity, a ˜ v. For others, acceleration is a scalar quantity, which describes the change in speed Δ|v| or Δ|v|/Δt (as opposed to the change in velocity). The main difficulty with the concept of acceleration therefore lies in developing a correct understanding of its direction. The free iOS app AccelVisu supports students in acquiring a correct conception of acceleration by showing acceleration arrows directly at moving objects.

  20. TURBULENT SHEAR ACCELERATION

    SciTech Connect

    Ohira, Yutaka

    2013-04-10

    We consider particle acceleration by large-scale incompressible turbulence with a length scale larger than the particle mean free path. We derive an ensemble-averaged transport equation of energetic charged particles from an extended transport equation that contains the shear acceleration. The ensemble-averaged transport equation describes particle acceleration by incompressible turbulence (turbulent shear acceleration). We find that for Kolmogorov turbulence, the turbulent shear acceleration becomes important on small scales. Moreover, using Monte Carlo simulations, we confirm that the ensemble-averaged transport equation describes the turbulent shear acceleration.

  1. ELECTRON HEATING AND ACCELERATION BY MAGNETIC RECONNECTION IN HOT ACCRETION FLOWS

    SciTech Connect

    Ding Jian; Yuan Feng; Liang, Edison

    2010-01-10

    Both analytical and numerical works show that magnetic reconnection must occur in hot accretion flows. This process will effectively heat and accelerate electrons. In this paper, we use the numerical hybrid simulation of magnetic reconnection plus the test-electron method to investigate the electron acceleration and heating due to magnetic reconnection in hot accretion flows. We consider fiducial values of density, temperature, and magnetic parameter beta{sub e} (defined as the ratio of the electron pressure to the magnetic pressure) of the accretion flow as n{sub 0} approx 10{sup 6} cm{sup -3}, T {sup 0}{sub e} approx 2 x 10{sup 9} K, and beta{sub e} = 1. We find that electrons are heated to a higher temperature T{sub e} = 5 x 10{sup 9} K, and a fraction eta approx 8% of electrons are accelerated into a broken power-law distribution, dN(gamma) propor to gamma{sup -p}, with p approx 1.5 and 4 below and above approx1 MeV, respectively. We also investigate the effect of varying beta and n{sub 0}. We find that when beta{sub e} is smaller or n{sub 0} is larger, i.e., the magnetic field is stronger, T{sub e} , eta, and p all become larger.

  2. Measurement of the tau- to eta pi-pi+pi-nu tau Branching Fraction and a Search for a Second-Class Current in the tau- to eta'(958)pi-nu tau Decay

    SciTech Connect

    Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, David Nathan; Button-Shafer, J.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /Frascati /Genoa U. /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /Pisa U. /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2008-03-24

    The {tau}{sup -} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} decay with the {eta} {yields} {gamma}{gamma} mode is studied using 384 fb{sup -1} of data collected by the BABAR detector. The branching fraction is measured to be (1.60 {+-} 0.05 {+-} 0.11) x 10{sup -4}. It is found that {tau}{sup -} {yields} f{sub 1}(1285){pi}{sup -} {nu}{sub {tau}} {yields} {eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} is the dominant decay mode with a branching fraction of (1.11 {+-} 0.06 {+-} 0.05) x 10{sup -4}. The first error on the branching fractions is statistical and the second systematic. In addition, a 90% confidence level upper limit on the branching fraction of the {tau}{sup -} {yields} {eta}{prime}(958){pi}{sup -}{nu}{sub {tau}} decay is measured to be 7.2 x 10{sup -6}. This last decay proceeds through a second-class current and is expected to be forbidden in the limit of isospin symmetry.

  3. Muon Collider Progress: Accelerators

    SciTech Connect

    Zisman, Michael S.

    2011-09-10

    A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

  4. New Targets for New Accelerators

    NASA Astrophysics Data System (ADS)

    Frentz, Bryce; Manukyan, Khachatur; Aprahamian, Ani

    2013-10-01

    New accelerators, such as the 5 MV Sta Ana accelerator at the University of Notre Dame, will produce more powerful beams up to 100's of μAmps. These accelerators require a complete rethinking of target preparation since the high intensity of such beams would melt conventional targets. Traditionally, accelerator targets are made with a tantalum backing because of its high atomic mass. However, tantalum is brittle, a poor conductor, and, if produced commercially, often contains impurities (e.g. fluorine) that produce undesirable background and reaction products. Tungsten, despite its brittle structure and poor conductivity, has a high atomic mass and lacks impurities, making it a more desirable backing. In conjunction with tungsten's properties, copper is robust and a far superior thermal conductor. We describe a new method of reactive joining that we developed for creating targets that use the advantageous properties of both tungsten and copper. This process involved placing a reactive mixture between tungsten and copper and applying a load force. The mixture is then ignited, and while under pressure, the system produces conditions to join the materials. We present our investigation to optimize the process of reactive joining, as well as some of the final target's properties. This work was supported by the National Science Foundation under Grant PHY-1068192.

  5. Accelerating Particles with Plasma

    SciTech Connect

    Litos, Michael; Hogan, Mark

    2014-11-05

    Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.

  6. Improved plasma accelerator

    NASA Technical Reports Server (NTRS)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  7. Photochemical Synthesis and Ligand Exchange Reactions of Ru(CO)[subscript 4] (Eta[superscript 2]-Alkene) Compounds

    ERIC Educational Resources Information Center

    Cooke, Jason; Berry, David E.; Fawkes, Kelli L.

    2007-01-01

    The photochemical synthesis and subsequent ligand exchange reactions of Ru(CO)[subscript 4] (eta[superscript2]-alkene) compounds has provided a novel experiment for upper-level inorganic chemistry laboratory courses. The experiment is designed to provide a system in which the changing electronic properties of the alkene ligands could be easily…

  8. 20 CFR 655.1135 - What appeals procedures are available concerning ETA's actions on a facility's Attestation?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... through a de novo hearing, the procedures contained in 29 CFR part 18 will apply to such hearings, except... Administrative Law Judges (29 CFR part 18, subpart B), will not apply to any hearing conducted pursuant to this...'s invalidation or suspension of a filed Attestation due to a discovery by ETA that it made an...

  9. Measurement of Time-Dependent CP-Violating Asymmetries in B^0 Meson Decays to eta' K^0_L

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2005-08-23

    The authors present a preliminary measurement of CP-violating parameters S and C from fits of the time-dependence of B{sup 0} meson decays to {eta}'K{sub L}{sup 0}. The data were recorded with the BABAR detector at PEP-II and correspond to 232 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation through the {Upsilon}(4S) resonance. By fitting the time-dependent CP asymmetry of the reconstructed B{sup 0} {yields} {eta}'K{sub L}{sup 0} events, they find S = 0.60 {+-} 0.31 {+-} 0.04 and C = 0.10 {+-} 0.21 {+-} 0.03, where the first error quoted is statistical and the second is systematic. They also perform a combined fit using both {eta}'K{sub S}{sup 0} and {eta}'K{sub L}{sup 0} data, and find S = 0.36 {+-} 0.13 {+-} 0.03 and C = -0.16 {+-} 0.09 {+-} 0.02.

  10. 20 CFR 655.1055 - Notice to the Employment and Training Administration (ETA) and the Attorney General (AG).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Notice to the Employment and Training Administration (ETA) and the Attorney General (AG). 655.1055 Section 655.1055 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR TEMPORARY EMPLOYMENT OF FOREIGN WORKERS IN THE UNITED STATES Enforcement of the Attestation...

  11. 20 CFR 655.1135 - What appeals procedures are available concerning ETA's actions on a facility's Attestation?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Nurses? § 655.1135 What appeals procedures are available concerning ETA's actions on a facility's...) representing nurses at the facility shall be a party to the appeal. Appeals shall be in writing; shall set..., the procedures contained in 29 CFR part 18 will apply to such hearings, except that: (1) The...

  12. He II 4686 in eta Carinae: no significant changes between 2009.0 and 2014.6

    NASA Astrophysics Data System (ADS)

    Teodoro, Mairan; Heathcote, Bernard; Richardson, Noel; Luckas, Paul; Walter, Frederick; Prates, Rodrigo; Hickel, Gabriel; Coimbra, Adriano M.; Navarete, Felipe; Locke, Malcolm; Bohlsen, Terry; Damineli, Augusto; Jablonski, Francisco; Henrique, William; Powles, Jonathan; West, Julian; Andrade, Thiago A.; Fernandez-Lajus, Eduardo; Gull, Theodore; Corcoran, Michael F.; Groh, Jose H.; Hamaguchi, Kenji; Madura, Thomas; St-Jean, Lucas; Weigelt, Gerd

    2014-09-01

    We are conducting a multi-observatory campaign focused on the monitoring of He II 4686 emission across the periastron event of eta Carinae. The behavior of the equivalent width of the He II 4686 emission line across the 2014.6 event is similar to that observed in 2009.0.

  13. The Student Monograph. Original Articles by Student Gammans, 1995 Edition. The Eta Sigma Gamma Monograph Series, Volume 13, Number 1.

    ERIC Educational Resources Information Center

    1995

    This publication contains a selection of undergraduate and graduate student research papers offered to the Eta Sigma Gamma Society in the health science disciplines. Articles include: (1) "The Development of Public/Private Partnerships and Their Impact on the Future of Public Health" (James Broadbear); (2) "Cancer Knowledge, Self-Efficacy and…

  14. 78 FR 32460 - Comment Request for Information Collection for ETA Form 232, Domestic Agricultural In-Season Wage...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-30

    ... Federal or State minimum wage, whichever is higher.'' The collection is also required by regulations for... legal federal or State minimum wage rate, whichever is highest unless special procedures apply to the... Agricultural In-Season Wage Report and ETA Form 232-A, Wage Survey Interview Record, Extension with...

  15. ASSESSMENT OF ETA-CMAQ FORECASTS OF PARTICULATE MATTER DISTRIBUTIONS THROUGH COMPARISONS WITH SURFACE NETWORK AND SPECIALIZED MEASUREMENTS

    EPA Science Inventory

    An air-quality forecasting (AQF) system based on the National Weather Service (NWS) National Centers for Environmental Prediction's (NCEP's) Eta model and the U.S. EPA's Community Multiscale Air Quality (CMAQ) Modeling System is used to simulate the distributions of tropospheric ...

  16. Multiple Velocity Components of Narrow-lined Absorption Arising from the Ejecta of AG Car, P Cyg, and Eta Car.

    NASA Astrophysics Data System (ADS)

    Vieira Kober, Gladys; Gull, T. R.; Bruhweiler, F.; Nielsen, K. E.; Hill, G.

    2007-12-01

    Luminous Blue Variables (LBVs) are a small group of massive objects, with a past characterized by occasional outbursts. Well known members in our galaxy are Eta Car, AG Car, HR Car and P Cyg. HST/STIS observations of Eta Car show a very complex and rich circumstellar absorption spectrum. Of the 20 distinct absorption systems, the ionized strong absorber at -146 km/s (Little Homunculus) shows lines from transitions originating from mainly singly ionized iron-group elements. Curve-of-growth analysis for Fe II lines plus photo-ionization and statistical equilibrium modeling indicated a temperature Te = 6400 K and density n 5x107 cm-3. AG Car and P Cyg have, like Eta Car, circumstellar nebulae which likely are remnants of typical LBV mass loss events. Spectral analysis of high resolution VLT/UVES data for AG Car and Keck/HIRES data for P Cyg also reveal multiple narrow absorption components with excitation and velocities similar to Eta Car's Little Homunculus. In this poster we present curve-of-growth analysis for Fe II lines for the narrow components around AG Car and P Cyg, and temperature estimates based on level populations for these absorbers. We compare the absorbing features around these three LBVs, providing clues to wind structures and ejections for these massive stars. We thank NASA, STScI, Keck and ESO for providing resources and spectra analyzed in this poster, recorded with HST/STIS, Keck/HIRES and VLT/UVES.

  17. 77 FR 37713 - Comment Request for Information Collection for ETA 9162, Random Audit of EUC 2008 Claimants...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... Employment and Training Administration Comment Request for Information Collection for ETA 9162, Random Audit... collection of data about Random Audit of Claimants in the Emergency Unemployment Compensation Program of 2008... is intended to provide data describing random audits of the work search provision of Public Law...

  18. High mobility of flap endonuclease 1 and DNA polymerase eta associated with replication foci in mammalian S-phase nucleus.

    PubMed

    Solovjeva, Lioudmila; Svetlova, Maria; Sasina, Lioudmila; Tanaka, Kyoji; Saijo, Masafumi; Nazarov, Igor; Bradbury, Morton; Tomilin, Nikolai

    2005-05-01

    Originally detected in fixed cells, DNA replication foci (RFi) were later visualized in living cells by using green fluorescent protein (GFP)-tagged proliferating cell nuclear antigen (PCNA) and DNA ligase I. It was shown using fluorescence redistribution after photobleaching (FRAP) assay that focal GFP-PCNA slowly exchanged, suggesting the existence of a stable replication holocomplex. Here, we used the FRAP assay to study the dynamics of the GFP-tagged PCNA-binding proteins: Flap endonuclease 1 (Fen1) and DNA polymerase eta (Pol eta). We also used the GFP-Cockayne syndrome group A (CSA) protein, which does associate with transcription foci after DNA damage. In normal cells, GFP-Pol eta and GFP-Fen1 are mobile with residence times at RFi (t(m)) approximately 2 and approximately 0.8 s, respectively. GFP-CSA is also mobile but does not concentrate at discrete foci. After methyl methanesulfonate (MMS) damage, the mobile fraction of focal GFP-Fen1 decreased and t(m) increased, but it then recovered. The mobilities of focal GFP-Pol eta and GFP-PCNA did not change after MMS. The mobility of GFP-CSA did not change after UV-irradiation. These data indicate that the normal replication complex contains at least two mobile subunits. The decrease of the mobile fraction of focal GFP-Fen1 after DNA damage suggests that Fen1 exchange depends on the rate of movement of replication forks. PMID:15758026

  19. The Eta Model Surface Hydrologic Cycle of the Columbia and Colorado Basins

    NASA Astrophysics Data System (ADS)

    Luo, Y.; Berbery, E. H.; Mitchell, K. E.

    2004-05-01

    The surface hydrology of the United States western basins is investigated using the National Centers for Environmental Prediction Eta model operational forecasts. During recent years the model has been subject to changes and upgrades that affected positively its performance. We discuss these effects on the surface hydrologic cycle by analyzing the period June 1995-May 2003. Results are compared with available precipitation observations and land surface hydrologic estimates resulting from the Variable Infiltration Capacity (VIC) macroscale hydrologic model. A fairly large disparity between the observed precipitation estimates with and without orography correction is found in the long term area-averages over the Columbia basin and over the Colorado basin. The basin-averaged model precipitation correlates well with the observations at monthly timescales, but a 34% positive difference with respect to the not-orographically corrected precipitation is found over the Columbia basin; the difference is reduced to 2% when using the orographically corrected precipitation. The excess in the model forecast precipitation is mainly found during the winter months, and seems related both to the model's large scale precipitation component, but also to the underestimation of gauge-based precipitation measurements. The model bias over the Colorado basin is largest during summer, and it is suggested that the limited performance of the convective precipitation component is the one that leads to the underestimation of the precipitation. The mean fields of the hydrological variables in the Eta model are in qualitative agreement with those from the VIC model at regional-to-large scales. As expected, the largest differences are found near mountains and the western coastline. While the mean fields of precipitation, evaporation, runoff and normalized soil moisture are in general agreement, important differences arise in their mean annual cycle over the two basins: snow melt in the Eta model

  20. High-Velocity Absorption Features in FUSE Spectra of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Sonneborn, G.; Iping, R. C.; Gull, T. R.; Vieira, G.

    2002-12-01

    Numerous broad (200 to 1000 km/sec) features in the FUSE spectrum (905-1187 A) of eta Carinae are identified as absorption by a forest of high-velocity narrow lines formed in the expanding circumstellar envelope. These features were previously thought to be P-Cygni lines arising in the wind of the central star. The features span a heliocentric velocity range of -140 to -580 km/sec and are seen prominently in low-ionization ground-state transitions (e.g. N I 1134-35, Fe II 1145-42, 1133, 1127-22, P II 1153, C I 1158) in addition to C III] 1176 A. The high-velocity components of the FUSE transitions have depths about 50% below the continuum. The identifications are consistent with the complex velocity structures seen in ground- and excited-state transitions of Mg I, Mg II, Fe II, V II, etc observed in STIS/E230H spectra (see accompanying posters by Gull, Vieira, and Danks). The origin of other broad features of similar width and depth in the FUSE spectrum, but without low-velocity ISM absorption, are unidentified. However, they are suspected of being absorption of singly-ionized iron-peak elements (e.g. Fe II, V II, Cr II) out of excited levels 1,000 to 20,000 cmE-1 above the ground state. The high-velocity features seen in Fe II 1145 are also present in Fe II 1608 (STIS/E140M), but are highly saturated in the latter. Since these transitions have nearly identical log (flambda) (1.998 vs. 2.080), the differences in the profiles are attributable to the different aperture sizes used (30x30 arcsec for FUSE, 0.2x0.2 arcsec for STIS/E140M). The high-velocity gas appears to be very patchy or has a small covering factor near the central star. Eta Carinae has been observed several times by FUSE over the past three years. The FUSE flux levels and spectral features in eta Car are essentially unchanged over the 2000 March to June 2002 period, establishing a baseline far-UV spectrum in advance of the predicted spectroscopic miniumum in 2003.