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Sample records for 6d ionization cooling

  1. Helical FOFO Snake for 6D Ionization Cooling of Muons

    SciTech Connect

    Alexahin, Y.

    2010-03-30

    A channel for 6D ionization cooling of muons is described which consists of periodically inclined solenoids of alternating polarity, liquid hydrogen absorbers placed inside the solenoids and RF cavities between them. An important feature of such a channel (called Helical FOFO snake) is that it can cool simultaneously muons of both signs. Theoretical considerations as well as results of simulations with G4beamline are presented which show that a 200 MHz HFOFO snake has sufficient acceptance to be used for initial 6D cooling in muon colliders and neutrino factories.

  2. Helical FOFO snake for 6D ionization cooling of muons

    SciTech Connect

    Alexahin, Y.; /Fermilab

    2009-10-01

    A channel for 6D ionization cooling of muons is described which consists of periodically inclined solenoids of alternating polarity, liquid hydrogen absorbers placed inside solenoids and RF cavities between them. Important feature of such channel (called Helical FOFO snake) is that it can cool simultaneously muons of both signs. Theoretical considerations as well as results of simulations with G4Beamline are presented which show that 200MHz HFOFO snake has sufficient acceptance to be used for initial 6D cooling in muon colliders and neutrino factories.

  3. 6D Ionization Cooling Channel with Resonant Dispersion Generation

    SciTech Connect

    Palmer, R.B.; Alexahin, Yuri I.; Yonehara, K.; /Fermilab

    2007-06-01

    For muons with preferable for ionization cooling momentum <300MeV/c the longitudinal motion is naturally undamped. In order to provide the longitudinal damping a correlation between muon momentum and transverse position--described in terms of the dispersion function--should be introduced. In the present report we consider the possibility of dispersion generation in a periodic sequence of alternating solenoids (FOFO channel) by choosing the tune in the second passband (i.e. above half-integer per cell) and tilting the solenoids in adjacent cells in the opposite direction. Analytical estimates for equilibrium emittances and cooling rates are presented.

  4. 6D Muon Ionization Cooling with an Inverse Cyclotron

    SciTech Connect

    Summers, D. J.; Bracker, S. B.; Cremaldi, L. M.; Godang, R.; Palmer, R. B.

    2006-03-20

    A large admittance sector cyclotron filled with LiH wedges surrounded by helium or hydrogen gas is explored. Muons are cooled as they spiral adiabatically into a central swarm. As momentum approaches zero, the momentum spread also approaches zero. Long bunch trains coalesce. Energy loss is used to inject the muons into the outer rim of the cyclotron. The density of material in the cyclotron decreases adiabatically with radius. The sector cyclotron magnetic fields are transformed into an azimuthally symmetric magnetic bottle in the center. Helium gas is used to inhibit muonium formation by positive muons. Deuterium gas is used to allow captured negative muons to escape via the muon catalyzed fusion process. The presence of ionized gas in the center may automatically neutralize space charge. When a bunch train has coalesced into a central swarm, it is ejected axially with an electric kicker pulse.

  5. Status of Studies of Achromat-based 6D Ionization Cooling Rings for Muons

    SciTech Connect

    Ding, X.; Kirk, H.; Cline, D.; Garren, A.A.; Berg, J.S.

    2011-09-04

    Six dimensional ionization cooling of muons is needed to achieve the necessary luminosity for a muon collider. If that cooling could occur over multiple turns in a closed ring, there would be significant cost savings over a single-pass cooling channel. We report on the status of a cooling ring with achromatic arcs. The achromatic design permits the design to easily switch between a closed ring and a snaking geometry on injection or extraction from the ring. The ring is designed with sufficient space in each superperiod for injection and extraction magnets. We describe the ring's lattice design, performance, and injection/extraction requirements.

  6. Circularly Inclined Solenoid Channel for 6D Ionization Cooling of Muons

    SciTech Connect

    Alexahin, Y.; /Fermilab

    2009-05-01

    Ionization cooling is essential for realization of Muon Collider, muons beam based neutrino factories and other experiments involving muons. The simplest structure - absorber(s) immersed in alternating solenoidal magnetic field - provides only transverse cooling since the longitudinal motion in the most suitable momentum range (2-300MeV/c) is naturally anti-damped. To overcome this difficulty it is proposed to periodically tilt solenoids so that a rotating transverse magnetic field was created. By choosing the phase advance per period above a multiple of 2{pi} it is possible to ensure that muons with higher momentum make a longer path in the absorber (whether distributed or localized) thus providing longitudinal damping. Basic theory of such channel and results of tracking simulations are presented.

  7. 6D Cooling of a Circulating Muon Beam

    SciTech Connect

    Garren, A.; Cline, D.; Kahn, S.; Kirk, H.; Mills, F.

    2006-03-20

    We discuss the conceptual design of a system to reduce the 6D emittance of a circulating muon beam. This system utilizes ionization cooling to achieve 6D phase reduction of the beam. Our design is based on a hydrogen gas filled ring which incorporates optics consisting of weak-focusing dipoles and 200 MHz rf cavities which restore the ionization energy loss due to the muons traversing the hydrogen gas.

  8. Magnets for Muon 6D Cooling Channels

    SciTech Connect

    Johnson, Rolland; Flanagan, Gene

    2014-09-10

    The Helical Cooling Channel (HCC), an innovative technique for six-dimensional (6D) cooling of muon beams using a continuous absorber inside superconducting magnets, has shown considerable promise based on analytic and simulation studies. The implementation of this revolutionary method of muon cooling requires high field superconducting magnets that provide superimposed solenoid, helical dipole, and helical quadrupole fields. Novel magnet design concepts are required to provide HCC magnet systems with the desired fields for 6D muon beam cooling. New designs feature simple coil configurations that produce these complex fields with the required characteristics, where new high field conductor materials are particularly advantageous. The object of the program was to develop designs and construction methods for HCC magnets and design a magnet system for a 6D muon beam cooling channel. If successful the program would develop the magnet technologies needed to create bright muon beams for many applications ranging from scientific accelerators and storage rings to beams to study material properties and new sources of energy. Examples of these applications include energy frontier muon colliders, Higgs and neutrino factories, stopping muon beams for studies of rare fundamental interactions and muon catalyzed fusion, and muon sources for cargo screening for homeland security.

  9. Epicyclic Twin-Helix Ionization Cooling Simulations

    SciTech Connect

    Vasiliy Morozov, Yaroslav Derbenev, A. Afanaciev, R.P. Johnson

    2011-04-01

    Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a highluminosity muon collider. For the implementation of PIC, we earlier developed an epicyclic twin-helix channel with correlated behavior of the horizontal and vertical betatron motions and dispersion. We now insert absorber plates with short energy-recovering units located next to them at the appropriate locations in the twin-helix channel. We first demonstrate conventional ionization cooling in such a system with the optics uncorrelated. We then adjust the correlated optics state and induce a parametric resonance to study ionization cooling under the resonant condition.

  10. MANX, a 6-D Muon Beam Cooling Experiment for RAL

    SciTech Connect

    Yonehara, K.; Kashikhin, V.; Lamm, M.; Zlobin, A.; Abrams, R.; Ankenbrandt, C.; Cummings, M.A.C.; Johnson, R.P.; Kahn, S.; Maloney, J.; /Northern Illinois U.

    2009-05-01

    MANX is a six-dimensional muon ionization cooling demonstration experiment based on the concept of a helical cooling channel in which a beam of muons loses energy in a continuous helium or hydrogen absorber while passing through a special superconducting magnet called a helical solenoid. The goals of the experiment include tests of the theory of the helical cooling channel and the helical solenoid implementation of it, verification of the simulation programs, and a demonstration of effective six-dimensional cooling of a muon beam. We report the status of the experiment and in particular, the proposal to have MANX follow MICE at the Rutherford-Appleton Laboratory (RAL) as an extension of the MICE experimental program. We describe the economies of such an approach which allow the MICE beam line and much of the MICE apparatus and expertise to be reused.

  11. MANX, A 6-D Muon Cooling Demonstration Experiment

    SciTech Connect

    Roberts,Thomas; Alsharo'a, Mohammad; Hanlet, Pierrick M; Johnson, Rolland P; Kuchnir, Moyses; Paul, Kevin; Ankenbrandt, Charles; Moretti, Alfred; Popovic, Milorad; Yarba, Victor; Kaplan, Daniel; Yonehara, Katsuya

    2005-04-01

    Most ionization cooling schemes now under consideration are based on using many large flasks of liquid hydrogen energy absorber. One important example is the proposed Muon Ionization Cooling Experiment (MICE), which has recently been approved to run at the Rutherford Appleton Laboratory (RAL). In the work reported here, a potential muon cooling demonstration experiment based on a continuous liquid energy absorber in a helical cooling channel (HCC) is discussed. The original HCC used a gaseous energy absorber for the engineering advantage of combining the energy absorption and RF energy regeneration in hydrogen-filled RF cavities. In the Muon And Neutrino eXperiment (MANX) that is proposed here, a liquid-filled HCC is used without RF energy regeneration to achieve the largest possible cooling rate in six dimensions. In this case, the magnetic fields of the HCC must diminish as the muons lose momentum as they pass through the liquid energy absorber. The length of the MANX device is determined by the maximum momentum of the muon test beam and the maximum practical field that can be sustained at the magnet coils. We have studied a 3 meter-long HCC example that could be inserted between the MICE spectrometers at RAL.

  12. Integrating the MANX 6-D Muon Cooling Experiment with the MICE Spectrometers

    SciTech Connect

    Kahn, S.A.; Abrams, R.J.; Ankenbrandt, C.; Cummings, M.A.C.; Johnson, R.P.; Roberts, T.; Yonehara, K.; /Fermilab

    2009-05-01

    The MANX experiment is to demonstrate the reduction of 6D muon phase space emittance using a continuous liquid absorber to provide ionization cooling in a helical solenoid magnetic channel. The experiment involves the construction of a short two-period long helical cooling channel (HCC) to reduce the muon invariant emittance by a factor of two. The HCC would replace the current cooling section of the MICE experiment now being setup at the Rutherford Appleton Laboratory. The MANX experiment would use the existing MICE spectrometers and muon beam line. This paper shall consider the various approaches to integrate MANX into the RAL hall using the MICE spectrometers. This study shall discuss the matching schemes used to minimize losses and prevent emittance growth between the MICE spectrometers and the MANX HCC. Also the placement of additional detection planes in the matching region and the HCC to improve the resolution will be examined.

  13. Epicyclic helical channels for parametric resonance ionization cooling

    SciTech Connect

    Johson, Rolland Paul; Derbenev, Yaroslav

    2015-08-23

    Proposed next-generation muon colliders will require major technical advances to achieve rapid muon beam cooling requirements. Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a high-luminosity muon collider. In PIC, a half-integer parametric resonance causes strong focusing of a muon beam at appropriately placed energy absorbers while ionization cooling limits the beam’s angular spread. Combining muon ionization cooling with parametric resonant dynamics in this way should then allow much smaller final transverse muon beam sizes than conventional ionization cooling alone. One of the PIC challenges is compensation of beam aberrations over a sufficiently wide parameter range while maintaining the dynamical stability with correlated behavior of the horizontal and vertical betatron motion and dispersion. We explore use of a coupling resonance to reduce the dimensionality of the problem and to shift the dynamics away from non-linear resonances. PIC simulations are presented.

  14. Parametric-Resonance Ionization Cooling in Twin-Helix.

    SciTech Connect

    V.S. Morozov, Ya.S. Derbenev, A. Afanasev, R.P. Johnson, Erdelyi. B., J.A. Maloney

    2011-09-01

    Parametric-resonance Ionization Cooling (PIC) is proposed as the final 6D cooling stage of a highluminosity muon collider. For the implementation of PIC, we developed an epicyclic twin-helix channel with correlated optics. Wedge-shaped absorbers immediately followed by short rf cavities are placed into the twin-helix channel. Parametric resonances are induced in both planes using helical quadrupole harmonics. We demonstrate resonant dynamics and cooling with stochastic effects off using GEANT4/G4beamline. We illustrate compensation of spherical aberrations and benchmark COSY Infinity, a powerful tool for aberration analysis and compensation.

  15. Optics for Phase Ionization Cooling of Muon Beams

    SciTech Connect

    R.P. Johnson; S.A. Bogacz; Y.S. Derbenev

    2006-06-26

    The realization of a muon collider requires a reduction of the 6D normalized emittance of an initially generated muon beam by a factor of more than 106. Analytical and simulation studies of 6D muon beam ionization cooling in a helical channel filled with pressurized gas or liquid hydrogen absorber indicate that a factor of 106 is possible. Further reduction of the normalized 4D transverse emittance by an additional two orders of magnitude is envisioned using Parametric-resonance Ionization Cooling (PIC). To realize the phase shrinkage effect in the parametric resonance method, one needs to design a focusing channel free of chromatic and spherical aberrations. We report results of our study of a concept of an aberration-free wiggler transport line with an alternating dispersion function. Resonant beam focusing at thin beryllium wedge absorber plates positioned near zero dispersion points then provides the predicted PIC effect.

  16. Ionization Cooling using Parametric Resonances

    SciTech Connect

    Johnson, Rolland P.

    2008-06-07

    Ionization Cooling using Parametric Resonances was an SBIR project begun in July 2004 and ended in January 2008 with Muons, Inc., (Dr. Rolland Johnson, PI), and Thomas Jefferson National Accelerator Facility (JLab) (Dr. Yaroslav Derbenev, Subcontract PI). The project was to develop the theory and simulations of Parametric-resonance Ionization Cooling (PIC) so that it could be used to provide the extra transverse cooling needed for muon colliders in order to relax the requirements on the proton driver, reduce the site boundary radiation, and provide a better environment for experiments. During the course of the project, the theoretical understanding of PIC was developed and a final exposition is ready for publication. Workshops were sponsored by Muons, Inc. in May and September of 2007 that were devoted to the PIC technique. One outcome of the workshops was the interesting and somewhat unexpected realization that the beam emittances using the PIC technique can get small enough that space charge forces can be important. A parallel effort to develop our G4beamline simulation program to include space charge effects was initiated to address this problem. A method of compensating for chromatic aberrations by employing synchrotron motion was developed and simulated. A method of compensating for spherical aberrations using beamline symmetry was also developed and simulated. Different optics designs have been developed using the OptiM program in preparation for applying our G4beamline simulation program, which contains all the power of the Geant4 toolkit. However, no PIC channel design that has been developed has had the desired cooling performance when subjected to the complete G4beamline simulation program. This is believed to be the consequence of the difficulties of correcting the aberrations associated with the naturally large beam angles and beam sizes of the PIC method that are exacerbated by the fringe fields of the rather complicated channel designs that have been

  17. MICE: The International Muon Ionization Cooling Experiment

    SciTech Connect

    Kaplan, Daniel M.

    2006-03-20

    Ionization cooling of a muon beam is a key technique for a Neutrino Factory or Muon Collider. An international collaboration is mounting an experiment to demonstrate muon ionization cooling at the Rutherford Appleton Laboratory. We aim to complete the experiment by 2010.

  18. Feasibility Study of Compact Gas-Filled Storage Ring for 6D Cooling of Muon Beams

    SciTech Connect

    A. Garren, J. Kolonlo

    2005-10-31

    The future of elementary particle physics in the USA depends in part on the development of new machines such as the International Linear Collider, Muon Collider and Neutrino Factories which can produce particle beams of higher energy, intensity, or particle type than now exists. These beams will enable the continued exploration of the world of elementary particles and interactions. In addition, the associated development of new technologies and machines such as a Muon Ring Cooler is essential. This project was to undertake a feasibility study of a compact gas-filled storage ring for 6D cooling of muon beams. The ultimate goal, in Phase III, was to build, test, and operate a demonstration storage ring. The preferred lattice for the storage ring was determined and dynamic simulations of particles through the lattice were performed. A conceptual design and drawing of the magnets were made and a study of the RF cavity and possible injection/ejection scheme made. Commercial applications for the device were investigated and the writing of the Phase II proposal completed. The research findings conclude that a compact gas-filled storage ring for 6D cooling of muon beams is possible with further research and development.

  19. On analog simulation of ionization cooling of muons

    SciTech Connect

    Xie, Ming

    2001-06-18

    Analog simulation, proposed here as an alternative approach for the study of ionization cooling of muons, is a scaled cooling experiment, using protons instead of muons as simulation particles. It is intended to be an effective and flexible, quick and inexpensive experiment for the understanding and validation of unprecedentedly complicated cooling physics, for the demonstration and optimization of various elaborated techniques for beam manipulation in 6D phase space. It can be done and perhaps should be done before the costly and time-consuming development of extremely challenging, muon-specific cooling technology. In a nutshell, the idea here is to build a toy machine in a playground of ideas, before staking the Imperial Guard of Napoleon into the bloody battlefield of Waterloo.

  20. The MICE Demonstration of Ionization Cooling

    SciTech Connect

    Pasternak, J.; Blackmore, V.; Hunt, C.; Lagrange, J-B.; Long, K.; Collomb, N.; Snopok, P.

    2015-05-01

    Muon beams of low emittance provide the basis for the intense, well-characterised neutrino beams necessary to elucidate the physics of flavour at the Neutrino Factory and to provide lepton-antilepton collisions at energies of up to several TeV at the Muon Collider. The International Muon Ionization Cooling Experiment (MICE) will demonstrate ionization cooling, the technique by which it is proposed to reduce the phase-space volume occupied by the muon beam at such facilities. In an ionization cooling channel, the muon beam passes through a material (the absorber) in which it loses energy. The energy lost is then replaced using RF cavities. The combined effect of energy loss and re-acceleration is to reduce the transverse emittance of the beam (transverse cooling). A major revision of the scope of the project was carried out over the summer of 2014. The revised project plan, which has received the formal endorsement of the international MICE Project Board and the international MICE Funding Agency Committee, will deliver a demonstration of ionization cooling by September 2017. In the revised configuration a central lithium-hydride absorber provides the cooling effect. The magnetic lattice is provided by the two superconducting focus coils and acceleration is provided by two 201 MHz single-cavity modules. The phase space of the muons entering and leaving the cooling cell will be measured by two solenoidal spectrometers. All the superconducting magnets for the ionization cooling demonstration are available at the Rutherford Appleton Laboratory and the first single-cavity prototype is under test in the MuCool Test Area at Fermilab. The design of the cooling demonstration experiment will be described together with a summary of the performance of each of its components. The cooling performance of the revised configuration will also be presented.

  1. Progress on muon parametric-resonance ionization cooling channel development

    SciTech Connect

    V.S. Morozov, Ya.S. Derbenev, A. Afanasev, K.B. Beard, R.P. Johnson, B. Erdelyi, J.A. Maloney

    2012-07-01

    Parametric-resonance Ionization Cooling (PIC) is intended as the final 6D cooling stage of a high-luminosity muon collider. To implement PIC, a continuous-field twin-helix magnetic channel was developed. A 6D cooling with stochastic effects off is demonstrated in a GEANT4/G4beamline model of a system where wedge-shaped Be absorbers are placed at the appropriate dispersion points in the twin-helix channel and are followed by short rf cavities. To proceed to cooling simulations with stochastics on, compensation of the beam aberrations from one absorber to another is required. Initial results on aberration compensation using a set of various-order continuous multipole fields are presented. As another avenue to mitigate the aberration effect, we optimize the cooling channel's period length. We observe a parasitic parametric resonance naturally occurring in the channel's horizontal plane due to the periodic beam energy modulation caused by the absorbers and rf. We discuss options for compensating this resonance and/or properly combining it with the induced half-integer parametric resonance needed for PIC.

  2. STATUS OF THE INTERNATIONAL MUON IONIZATION COOLING EXPERIMENT(MICE)

    SciTech Connect

    Zisman, Michael S.

    2007-07-18

    An international experiment to demonstrate muon ionization cooling is scheduled for beam at Rutherford Appleton Laboratory (RAL) in 2007. The experiment comprises one cell of the Study II cooling channel [1], along with upstream and downstream detectors to identify individual muons and measure their initial and final 6D phase-space parameters to a precision of 0.1%. Magnetic design of the beam line and cooling channel are complete and portions are under construction. The experiment will be described, including cooling channel hardware designs, fabrication status, and running plans. Phase 1 of the experiment will prepare the beam line and provide detector systems, including time-of-flight, Cherenkov, scintillating-fiber trackers and their spectrometer solenoids, and an electromagnetic calorimeter. The Phase 2 system will add the cooling channel components, including liquid-hydrogen absorbers embedded in superconducting Focus Coil solenoids, 201-MHz normal-conducting RF cavities, and their surrounding Coupling Coil solenoids. The MICE Collaboration goal is to complete the experiment by 2010; progress toward this is discussed.

  3. Muon Tracking Studies in a Skew Parametric Resonance Ionization Cooling Channel

    SciTech Connect

    Sy, Amy; Afanaciev, Andre; Derbenev, Yaroslav S.; Johnson, Rolland; Morozov, Vasiliy

    2015-09-01

    Skew Parametric-resonance Ionization Cooling (SPIC) is an extension of the Parametric-resonance Ionization Cooling (PIC) framework that has previously been explored as the final 6D cooling stage of a high-luminosity muon collider. The addition of skew quadrupoles to the PIC magnetic focusing channel induces coupled dynamic behavior of the beam that is radially periodic. The periodicity of the radial motion allows for the avoidance of unwanted resonances in the horizontal and vertical transverse planes, while still providing periodic locations at which ionization cooling components can be implemented. A first practical implementation of the magnetic field components required in the SPIC channel is modeled in MADX. Dynamic features of the coupled correlated optics with and without induced parametric resonance are presented and discussed.

  4. Stochastic processes in muon ionization cooling

    NASA Astrophysics Data System (ADS)

    Errede, D.; Makino, K.; Berz, M.; Johnstone, C. J.; Van Ginneken, A.

    2004-02-01

    A muon ionization cooling channel consists of three major components: the magnet optics, an acceleration cavity, and an energy absorber. The absorber of liquid hydrogen contained by thin aluminum windows is the only component which introduces stochastic processes into the otherwise deterministic acceleration system. The scattering dynamics of the transverse coordinates is described by Gaussian distributions. The asymmetric energy loss function is represented by the Vavilov distribution characterized by the minimum number of collisions necessary for a particle undergoing loss of the energy distribution average resulting from the Bethe-Bloch formula. Examples of the interplay between stochastic processes and deterministic beam dynamics are given.

  5. The International Muon Ionization Cooling Experiment: MICE and Neutrino Factories

    NASA Astrophysics Data System (ADS)

    Freemire, Ben

    2010-03-01

    The Muon Ionization Cooling Experiment (MICE) is an accelerator and particle physics experiment aimed at demonstrating the technique of ionization cooling on a beam of muons. Ionization cooling is the process by which muons are sent through an absorbing material, thereby losing energy and decreasing their normalized emittance. The muons are then reaccelerated in the appropriate direction with radio frequency (RF) cavities. This produces an overall reduction in transverse emittance of the muon beam. Ionization cooling could be a key technique in the design of a high intensity Neutrino Factory.

  6. Applications of an MPI Enhanced Simulated Annealing Algorithm on nuSTORM and 6D Muon Cooling

    SciTech Connect

    Liu, A.

    2015-06-01

    The nuSTORM decay ring is a compact racetrack storage ring with a circumference ~480 m using large aperture ($\\phi$ = 60 cm) magnets. The design goal of the ring is to achieve a momentum acceptance of 3.8 $\\pm$10% GeV/c and a phase space acceptance of 2000 $\\mu$m·rad. The design has many challenges because the acceptance will be affected by many nonlinearity terms with large particle emittance and/or large momentum offset. In this paper, we present the application of a meta-heuristic optimization algorithm to the sextupole correction in the ring. The algorithm is capable of finding a balanced compromise among corrections of the nonlinearity terms, and finding the largest acceptance. This technique can be applied to the design of similar storage rings that store beams with wide transverse phase space and momentum spectra. We also present the recent study on the application of this algorithm to a part of the 6D muon cooling channel. The technique and the cooling concept will be applied to design a cooling channel for the extracted muon beam at nuSTORM in the future study.

  7. Parametric Resonance Ionization Cooling and Reverse Emittance Exchange for Muon Collider

    SciTech Connect

    Yaroslav Derbenev

    2005-09-18

    Two methods to cool muon beams deeply below the limit conventionally established for the ionization cooling are proposed. In Phase Ionization Cooling (PIC), the beam is focused at wedge absorber plates each half of particle oscillation period by imposing a weak parametric resonance along the beam path. The resonance growth of particle amplitude is surmounted by the ionization cooling. At optimum, such arrangement results in reduction of each of two transverse emittances by an order of value in addition to the preceding 6D ionization cooling. Next, resonance focusing and transverse cooling can be continued in the regime of a fast Reverse Emittance Exchange (REMEX). Here, the sign of the absorber wedge is opposite to PIC while the dispersion increased. REMEX to be accompanied by the bunch lengthening and acceleration in order to maintain the relative energy spread at an appropriate level. The limitations due to energy straggling in absorber will be evaluated, and possibilities of beam conditioning against aberrations and muon space charge will be illustrated for specific beam transports. Estimates of Muon Collider luminosity versus muon production rate will be presented.

  8. Studies of the Twin Helix Parametric-resonance Ionization Cooling Channel with COSY INFINITY

    SciTech Connect

    J.A. Maloney, K.B. Beard, R.P. Johnson, A. Afanasev, S.A. Bogacz, Y.S. Derbenev, V.S. Morozov, B. Erdelyi

    2012-07-01

    A primary technical challenge to the design of a high luminosity muon collider is an effective beam cooling system. An epicyclic twin-helix channel utilizing parametric-resonance ionization cooling has been proposed for the final 6D cooling stage. A proposed design of this twin-helix channel is presented that utilizes correlated optics between the horizontal and vertical betatron periods to simultaneously focus transverse motion of the beam in both planes. Parametric resonance is induced in both planes via a system of helical quadrupole harmonics. Ionization cooling is achieved via periodically placed wedges of absorbing material, with intermittent rf cavities restoring longitudinal momentum necessary to maintain stable orbit of the beam. COSY INFINITY is utilized to simulate the theory at first order. The motion of particles around a hyperbolic fixed point is tracked. Comparison is made between the EPIC cooling channel and standard ionization cooling effects. Cooling effects are measured, after including stochastic effects, for both a single particle and a distribution of particles.

  9. Status of MICE, the international Muon Ionization Cooling Experiment

    SciTech Connect

    Sandstroem, R.

    2008-02-21

    An international experiment designed to demonstrate muon ionization cooling is being built at Rutherford Appleton Laboratory (RAL). The experiment consists of one cell of a Neutrino Factory cooling channel, along with upstream and downstream detectors to identify individual muons and measure their initial and final emittance to a precision of 0.1%. Magnetic design of the beamline and cooling channel are complete, and portions are under construction. This paper describes the experiment, including cooling channel hardware designs, fabrication status, and running plans.

  10. Epicyclic Helical Channels for Parametric Resonance Ionization Cooling

    SciTech Connect

    Andrei Afanaciev, Alex Bogacz, Yaroslav Derbenev, Kevin Beard, Valentin Ivanov, Rolland Johnson, Guimei Wang, Katsuya Yonehara

    2009-05-01

    In order to achieve cooling of muons in addition to 6D helical cooling channel (HCC) [1], we develop a technique based on a parametric resonance. The use of parametric resonances requires alternating dispersion, minimized at locations of thin absorbers, but maximized in between in order to compensate for chromatic aberrations [2]. These solutions can be combined in an Epicyclic Helical Cooling Channel (EHCC) that meets requirements of alternating dispersion of beam periodic orbit with best conditions for maintenance of stable beam transport in a continuous solenoid-type field [3]. We discuss here basic features and new simulation results for EHCC.

  11. Simulations of Parametric Resonance Ionization Cooling of Muon Beams

    SciTech Connect

    K. Beard; S.A. Bogacz; Y.S. Derbenev; R.P. Johnson; K. Paul; T.J. Roberts; K. Yonehara

    2005-05-16

    The technique of using a parametric resonance to allow better ionization cooling is being developed to create small beams so that high collider luminosity can be achieved with fewer muons. In the linear channel that is studied in this effort, a half integer resonance is induced such that the normal elliptical motion of particles in x-x' phase space becomes hyperbolic, with particles moving to smaller x and larger x' as they pass down the channel. Thin absorbers placed at the focal points of the channel then cool the angular divergence of the beam by the usual ionization cooling mechanism where each absorber is followed by RF cavities. Thus the phase space of the beam is compressed in transverse position by the dynamics of the resonance and its angular divergence is compressed by the ionization cooling mechanism. We report the first results of simulations of this process, including comparisons to theoretical cooling rates and studies of sensitivity to variations in absorber thickness and initial beam conditions.

  12. Homonuclear ionizing collisions of laser-cooled metastable helium atoms

    SciTech Connect

    Stas, R. J. W.; McNamara, J. M.; Hogervorst, W.; Vassen, W.

    2006-03-15

    We present a theoretical and experimental investigation of homonuclear ionizing collisions of laser-cooled metastable (2 {sup 3}S{sub 1}) helium atoms, considering both the fermionic {sup 3}He and bosonic {sup 4}He isotopes. The theoretical description combines quantum threshold behavior, Wigner's spin-conservation rule, and quantum-statistical symmetry requirements in a single-channel model, complementing a more complete close-coupling theory that has been reported for collisions of metastable {sup 4}He atoms. The model is supported with measurements (in the absence of light fields) of ionization rates in magneto-optically trapped samples that contain about 3x10{sup 8} atoms of a single isotope. The ionization rates are determined from measurements of trap loss due to light-assisted collisions combined with comparative measurements of the ion production rate in the absence and presence of trapping light. Theory and experiment show good agreement.

  13. Ionization and Cooling of a Hot Plasma with Temperature Fluctuations

    NASA Astrophysics Data System (ADS)

    Kholtygin, A. F.; Bratsev, V. F.; Ochkur, V. I.

    2002-01-01

    Cooling functions for a stationary plasma are calculated in a wide temperature range from 5·103 K to 108 K, both for a plasma with the solar abundances of elements and for a plasma with an anomalous chemical composition typical of Wolf—Rayet stars. The HILYS project is described, with the aim of calculating cross sections and rates of excitation by electron collision of atoms and ions with a charge Z 26 and principal electron quantum numbers n 10, needed to calculate the ionization and thermal states of a plasma and the development of methods of calculating the plasma's spectrum in the visible, UV, and x-ray ranges. The results of a calculation of cross sections and effective collision strengths obtained within the framework of the project are given. The influence of temperature fluctuations (T/T 0.16) on the relative ion abundances and the total cooling function is studied. It is shown that the presence of such fluctuations considerably increases the temperature range in which the abundances of ions of a given degree of ionization are not negligible, while the cooling function can differ considerably from that calculated for a one-temperature plasma. The contribution of dielectronic recombination to the total cooling function is investigated, and it proves to be significant only for a plasma with high abundances of heavy elements. The x-ray spectrum of the bright supergiant Pup is analyzed.

  14. Phase space density as a measure of cooling performance for the international muon ionization cooling experiment

    SciTech Connect

    Berg, J. S.

    2015-05-03

    The International Muon Ionization Cooling Experiment (MICE) is an experiment to demonstrate ionization cooling of a muon beam in a beamline that shares characteristics with one that might be used for a muon collider or neutrino factory. I describe a way to quantify cooling performance by examining the phase space density of muons, and determining how much that density increases. This contrasts with the more common methods that rely on the covariance matrix and compute emittances from that. I discuss why a direct measure of phase space density might be preferable to a covariance matrix method. I apply this technique to an early proposal for the MICE final step beamline. I discuss how matching impacts the measured performance.

  15. MICE: The International Muon Ionization Cooling Experiment: Phase Space Cooling Measurement

    SciTech Connect

    Hart, T. L.

    2010-03-30

    MICE is an experimental demonstration of muon ionization cooling using a section of an ionization cooling channel and a muon beam. The muons are produced by the decay of pions from a target dipping into the ISIS proton beam at Rutherford Appleton Laboratory (RAL). The channel includes liquid-hydrogen absorbers providing transverse and longitudinal momentum loss and high-gradient radiofrequency (RF) cavities for longitudinal reacceleration, all packed into a solenoidal magnetic channel. MICE will reduce the beam transverse emittance by about 10% for muon momenta between 140 and 240 MeV/c. Time-of-flight (TOF) counters, threshold Cherenkov counters, and a calorimeter will identify background electrons and pions. Spectrometers before and after the cooling section will measure the beam transmission and input and output emittances with an absolute precision of 0.1%.

  16. Polymerization, shock cooling and ionization of liquid nitrogen

    SciTech Connect

    Ross, M; Rogers, F

    2005-07-21

    The trajectory of thermodynamic states passed through by the nitrogen Hugoniot starting from the liquid and up to 10{sup 6} GPa has been studied. An earlier report of cooling in the doubly shocked liquid, near 50 to 100 GPa and 7500 K, is revisited in light of the recent discovery of solid polymeric nitrogen. It is found that cooling occurs when the doubly shocked liquid is driven into a volume near the molecular to polymer transition and raising the possibility of a liquid-liquid phase transition (LLPT). By increasing the shock pressure and temperature by an order of magnitude, theoretical calculations predict thermal ionization of the L shell drives the compression maxima to 5-6 fold compression at 10 Mbar (T {approx} 3.5 10{sup 5} K) and at 400 Mbar (T {approx} 2.3 10{sup 6} K) from K shell ionization. Near a pressure of 10{sup 6} GPa the K shell ionizes completely and the Hugoniot approaches the classical ideal gas compression fourfold limit.

  17. ICOOL: A SIMULATION CODE FOR IONIZATION COOLING OF MUON BEAMS.

    SciTech Connect

    FERNOW,R.C.

    1999-03-25

    Current ideas [1,2] for designing a high luminosity muon collider require significant cooling of the phase space of the muon beams. The only known method that can cool the beams in a time comparable to the muon lifetime is ionization cooling [3,4]. This method requires directing the particles in the beam at a large angle through a low Z absorber material in a strong focusing magnetic channel and then restoring the longitudinal momentum with an rf cavity. We have developed a new 3-D tracking code ICOOL for examining possible configurations for muon cooling. A cooling system is described in terms of a series of longitudinal regions with associated material and field properties. The tracking takes place in a coordinate system that follows a reference orbit through the system. The code takes into account decays and interactions of {approx}50-500 MeV/c muons in matter. Material geometry regions include cylinders and wedges. A number of analytic models are provided for describing the field configurations. Simple diagnostics are built into the code, including calculation of emittances and correlations, longitudinal traces, histograms and scatter plots. A number of auxiliary files can be generated for post-processing analysis by the user.

  18. A Study of Muon Ionization Cooling at MICE

    SciTech Connect

    Sakamoto, Hideyuki; /Osaka U.

    2010-02-01

    A Neutrino Factory based on a high-energy muon storage-ring is proposed to study neutrino oscillation with high precision. An emittance reduction of muon beam by ionization cooling, which has never been demonstrated in practice, is one of the critical issues for Neutrino Factory. The international Muon Ionisation Cooling Experiment (MICE) is the first experiment to verify an effect of the ionization cooling with muons. MICE will measure a change in transverse emittance of approximately 10% with a precision of {+-}0.1%. In order to meet the requirements, muon trackers based on 350 {micro}m diameter scintillating fibers have been proposed. The construction of such trackers is a very challenging task and some innovative techniques are needed to realize, since there have been no trackers made with such a small diameter of scintillating fibers in the world. Upstream and downstream SciFi trackers have been successfully constructed with the international collaboration of UK, US and Japan by 2008. Both of the trackers have been tested with cosmic-rays at the RAL by 2009, at which high tracking efficiencies more than 90% are measured for both trackers. It is also confirmed that by collecting the misalignments found in both of the trackers, the requirements for the emittance measurement is met.

  19. MICE: The International Muon Ionization Cooling Experiment: Diagnostic Systems

    SciTech Connect

    Bross, Alan D.; Hart, Terrence Lee; /IIT, Chicago

    2008-06-24

    The Muon Ionization Cooling Experiment will make detailed measurements of muon ionization cooling using a new constructed low-energy muon beam at the Rutherford Appleton Laboratory (RAL). The experiment is a single-particle experiment and utilizes many detector techniques from high energy physics experiments. To characterize and monitor the muon beamline, newly developed scintillating fiber profile monitors and scintillator paddle rate monitors are employed. In order to monitor the purity of the beam and tag the arrival time of individual muons, a dual aerogel Cherenkov system is used, and a plastic scintillator time-of-flight system will be used. The phase-space vectors of the muons will be measured by two identical spectrometer systems (one before and one after the cooling apparatus) which employ a fiber tracker system, and electron and muon calorimeters are used to tag outgoing muons. We will discuss the design of the MICE diagnostic systems, the operation, and give the first results from beam measurements in the MICE experimental hall.

  20. INTERACTION OF MUON BEAM WITH PLASMA DEVELOPED DURING IONIZATION COOLING

    SciTech Connect

    S. Ahmed, D. Kaplan, T. Roberts, L. Spentzouris, K. Beard

    2012-07-01

    Particle-in-cell simulations involving the interaction of muon beam (peak density 10{sup 18} m{sup 3}) with Li plasma (ionized medium) of density 10{sup 16}-10{sup 22} m{sup -3} have been performed. This study aimed to understand the effects of plasma on an incoming beam in order to explore scenario developed during the process of ionization cooling. The computer code takes into account the self-consistent electromagnetic effects of beam interacting with plasma. This study shows that the beam can pass through the plasma of densities four order of magnitude higher than its peak density. The low density plasmas are wiped out by the beam, however, the resonance is observed for densities of similar order. Study reveals the signature of plasma wakefield acceleration.

  1. The Reconstruction Software for the Muon Ionization Cooling Experiment Trackers

    SciTech Connect

    Dobbs, A.; Long, K.; Santos, E.; Adey, D.; Hanlet, P.; Heidt, C.

    2014-01-01

    The international Muon Ionisation Cooling Experiment (MICE) is designed to demonstrate the principle of muon ionization cooling, for application to a future Neutrino Factory or Muon Collider. In order to measure the change in emittance, MICE is equipped with a pair of high precision scintillating fibre trackers. The trackers are required to measure a 10% change in emittance to 1% accuracy (giving an overall precision of 0.1%). This paper describes the tracker reconstruction software, as a part of the overall MICE software framework, MAUS. Channel clustering is described, proceeding to the formation of space-points, which are then associated with particle tracks using pattern recognition algorithms. Finally a full custom Kalman track fit is performed, to account for energy loss and multiple scattering. Exemplar results are shown for Monte Carlo data.

  2. Strong-Field Ionization of Laser Cooled Li Atoms

    NASA Astrophysics Data System (ADS)

    Sharma, Sachin; Romans, Kevin; Fischer, Daniel

    2016-05-01

    Recently, our understanding of few-body effects has been substantially boosted by the development of intense femto- and attosecond laser sources. Observing the momenta of the fragments of atoms and molecules ionized in these strong fields provided new and before inconceivable insights in molecular and electronic dynamics. Here, we report on a new experiment, where the target atoms (6 Li) are laser cooled and trapped using a magneto optical trap (MOT). Momentum vectors of the target fragments will be measured using a reaction microscope (ReMi). The exclusivity of this setup is a combination of MOT and ReMi, thus dubbed as MOTReMi. Here, the advantages over standard COLTRIMS systems are multifold: Firstly, an unprecedented recoil ion momentum resolution can be achieved, as the target can be prepared at significantly lower temperatures. Second, the atoms can be optically prepared in the ground or in polarized excited states. In a first experimental campaign, studies on single ionization of laser excited and polarized Lithium atoms will be performed with circularly polarized light. This experiment can provide insight into the helicity-dependence of the ionization dynamics as the differences among co- and counter rotating electron and laser field, if any, can be investigated.

  3. RECENT PROGRESS IN SIX DIMENSIONAL IONIZATION COOLING TECHNIQUES FOR MUON BASED MACHINES.

    SciTech Connect

    KIM,K.J.; WANG,C.X.; BERG,J.S.; FERNOW,R.; KIRK,H.; PALMER,R.; BALBEKOV,V.; GARREN,A.A.

    2002-06-03

    Ionization cooling is an essential component of a neutrino factory or a muon collider. Ionization cooling in the transverse dimensions is reasonably straightforward, and has been incorporated in published neutrino factory studies. Achieving cooling in the longitudinal dimensions is more difficult, but has the potential to greatly improve the performance of neutrino factories, and is essential to muon colliders. Much progress has recently been made in describing ring cooling lattices which achieve cooling in all three phase space planes, and in the design of the required, but difficult, injection systems. Ring cooling lattices also have the potential of significantly reduced cost compared to single-pass cooling systems with comparable performance. We will present some recent lattice designs, describing their theory, features, and performance, including injection and extraction systems.

  4. G4BEAMLINE Simulations of Parametric Resonance Ionization Cooling of Muon Beams

    SciTech Connect

    Beard, Kevin; Bogacz, S. Alex; Derbenev, Yaroslav; Yonehara, Katsuya; Johnson, Rolland P.; Paul, Kevin; Roberts, Thomas J.

    2006-03-20

    The technique of using a parametric resonance to allow better ionization cooling is being developed to create small emittance beams so that high collider luminosity can be achieved with fewer muons. While parametric resonance ionization cooling (PIC) of muons has been shown to work in matrix-based simulations using OptiM when the system is properly tuned, doing the same using a much more detailed GEANT-based g4beamline simulation has been more difficult.

  5. A COMPLETE SCHEME FOR IONIZATION COOLING FOR A MUON COLLIDER.

    SciTech Connect

    PALMER,R.B.; BERG, J.S.; FERNOW, R.C.; GALLARDO, J.C.; KIRK, H.G.; ALEXAHIN, Y.; NEUFFER, D.; KAHN, S.A.; SUMMERS, D.

    2007-06-25

    A complete scheme for production and cooling a muon beam for three specified muon colliders is presented. Parameters for these muon colliders are given. The scheme starts with the front end of a proposed neutrino factory that yields bunch trains of both muon signs. Emittance exchange cooling in slow helical lattices reduces the longitudinal emittance until it becomes possible to merge the trains into single bunches, one of each sign. Further cooling in all dimensions is applied to the single bunches in further slow helical lattices. Final transverse cooling to the required parameters is achieved in 50 T solenoids using high TC superconductor at 4 K. Preliminary simulations of each element are presented.

  6. Status of the International Muon Ionization Cooling Experiment (MICE)

    SciTech Connect

    Zisman, Michael S.; Zisman, Michael S.

    2007-02-02

    An international experiment to demonstrate muonionization cooling is scheduled for beam at RutherfordAppleton Laboratory (RAL) in 2007. The experimentcomprises one cell of the Study II cooling channel [1],along with upstream and downstream detectors to identifyindividual muons and measure their initial and final 6Dphase-space parameters to a precision of 0.1percent. Magneticdesign of the beam line and cooling channel are completeand portions are under construction. The experiment willbe described, including cooling channel hardware designs,fabrication status, and running plans. Phase 1 of theexperiment will prepare the beam line and providedetector systems, including time-of-flight, Cherenkov,scintillating-fiber trackers and their spectrometersolenoids, and an electromagnetic calorimeter. The Phase2 system will add the cooling channel components,including liquid-hydrogen absorbers embedded insuperconducting Focus Coil solenoids, 201-MHz normalconductingRF cavities, and their surrounding CouplingCoil solenoids. The MICE Collaboration goal is tocomplete the experiment by 2010; progress toward this isdiscussed.

  7. Skew-Quad Parametric-Resonance Ionization Cooling: Theory and Modeling

    SciTech Connect

    Afanaciev, Andre; Derbenev, Yaroslav S.; Morozov, Vasiliy; Sy, Amy; Johnson, Rolland P.

    2015-09-01

    Muon beam ionization cooling is a key component for the next generation of high-luminosity muon colliders. To reach adequately high luminosity without excessively large muon intensities, it was proposed previously to combine ionization cooling with techniques using a parametric resonance (PIC). Practical implementation of PIC proposal is a subject of this report. We show that an addition of skew quadrupoles to a planar PIC channel gives enough flexibility in the design to avoid unwanted resonances, while meeting the requirements of radially-periodic beam focusing at ionization-cooling plates, large dynamic aperture and an oscillating dispersion needed for aberration corrections. Theoretical arguments are corroborated with models and a detailed numerical analysis, providing step-by-step guidance for the design of Skew-quad PIC (SPIC) beamline.

  8. g4beamline Simulations of Parametric Resonance Ionization Cooling of Muon Beams

    SciTech Connect

    Kevin Beard; Slawomir Bogacz; Yaroslav Derbenev; Katsuya Yonehara; Rolland P. Johnson; Kevin Paul; Thomas J. Roberts

    2005-09-19

    The technique of using a parametric resonance to allow better ionization cooling is being developed to create small beams so that high collider luminosity can be achieved with fewer muons. While parametric resonance ionization (PIC) cooling of muons has been shown to work in matrix-based simulations when the system is properly tuned, doing the same using a much more detailed GEANT-based g4beamline [1] simulation has proven more difficult. The starting point for this work is a the linear channel; a half integer resonance is induced such that the normal elliptical motion of particles in x-x' phase space becomes hyperbolic, with particles moving to smaller x and larger x' as they pass down the channel. Thin absorbers placed at the focal points of the channel then cool the angular divergence of the beam by the usual ionization cooling mechanism where each absorber is followed by RF cavities. Thus the phase space of the beam is compressed in transverse position by the dynamics of the resonance and its angular divergence is compressed by the ionization cooling mechanism. The g4beamline and OptiM [2] simulations show the importance of synchrotron motion as an averaging mechanism for chromatic detuning. Multiple scattering and energy straggling play a significant role that must be addressed via further optimizations and additional compensation solutions.

  9. Non-equilibirum ionization and cooling of metal-enriched gas in the presence of a photoionization background

    NASA Astrophysics Data System (ADS)

    Oppenheimer, Benjamin D.; Schaye, Joop

    2013-09-01

    Simulations of the formation of galaxies, as well as ionization models used to interpret observations of quasar absorption lines, generally either assume ionization equilibrium or ignore the presence of the extragalactic background (EGB) radiation. We introduce a method to compute the non-equilibrium ionization and cooling of diffuse gas exposed to the EGB. Our method iterates the ionization states of the 11 elements that dominate the cooling (H, He, C, N, O, Ne, Si, Mg, S, Ca and Fe) and uses tabulated ion-by-ion cooling and photo-heating efficiencies to update the temperature of the gas. Our reaction network includes radiative and di-electric recombination, collisional ionization, photoionization, Auger ionization and charge transfer. We verify that our method reproduces published results for collisional equilibrium, collisional non-equilibrium and photoionized equilibrium. Non-equilibrium effects can become very important in cooling gas, particularly below 106 K. Photoionization and non-equilibrium effects both tend to boost the degree of ionization and to reduce cooling efficiencies. The effect of the EGB is larger for lower densities (i.e. higher ionization parameters). Hence, photoionization affects (equilibrium and non-equilibrium) cooling more under isochoric than under isobaric conditions. Non-equilibrium effects are smaller in the presence of the EGB and are thus overestimated when using collisional-only processes. The inclusion of the EGB alters the observational diagnostics of diffuse, metal-enriched gas (e.g. metal absorption lines probed in quasar sight lines) even more significantly than the cooling efficiencies. We argue that the cooling efficiency should be considered if ionization models are used to infer physical conditions from observed line ratios, as the a priori probability of observing gas is lower if its cooling time is shorter. We provide online tables of ionization fractions and cooling efficiencies, as well as other data, for equilibrium

  10. Mysterious ionization in cooling flow filaments: a test with deep COS FUV spectroscopy

    NASA Astrophysics Data System (ADS)

    Tremblay, Grant

    2013-10-01

    The Cosmic Origins Spectrograph is capable of unraveling a two decade old mystery regarding the filamentary emission line nebulae found in the brightest cluster galaxies {BCGs} of cool core {CC} clusters. These kpc-scale filaments are characterized by elevated H-alpha luminosities and puzzling ionization states that cannot be accounted for by recombination or photionization alone, and are instead excited by an unknown ionization mechanism. The most hotly debated proposed solutions invoke thermal conduction, shocks, or cosmic-ray heating, but progress toward consensus awaits unambiguous spectral discriminants between these models that can only be found in the FUV. We propose deep {9 orbit}, off-nuclear observations of two strategically selected BCGs in well-studied cool core clusters with cross-spectrum archival datasets. We also propose a shorter {5 orbit} on-nuclear observation for one of our targets to assess possible AGN contributions to the spectra. These proposed observations represent critical tests that can unambiguously discriminate between the various candidate ionziation models. Constraining the mechanisms by which CC BCG filaments are excited remains one of the most important roadblocks to a better understanding of cooling from hot ambient medium to cold star forming clouds and filaments, a process important for both galaxy and black hole growth. It is therefore important that, before HST ends its mission and we lose FUV capability, we advance our understanding of this decades old mystery.

  11. Progress on a Cavity with Beryllium Walls for Muon Ionization Cooling Channel R&D.

    SciTech Connect

    Bowring, D. L.; DeMello, A. J.; Lambert, A. R.; Li, D.; Virostek, S.; Zisman, M.; Kaplan, D.; Palmer, R. B.

    2012-05-20

    The Muon Accelerator Program (MAP) collaboration is working to develop an ionization cooling channel for muon beams. An ionization cooling channel requires the operation of high-gradient, normal-conducting RF cavities in multi-Tesla solenoidal magnetic fields. However, experiments conducted at Fermilab?s MuCool Test Area (MTA) show that increasing the solenoidal field strength reduces the maximum achievable cavity gradient. This gradient limit is characterized by an RF breakdown process that has caused significant damage to copper cavity interiors. The damage may be caused by field-emitted electrons, focused by the solenoidal magnetic field onto small areas of the inner cavity surface. Local heating may then induce material fatigue and surface damage. Fabricating a cavity with beryllium walls would mitigate this damage due to beryllium?s low density, low thermal expansion, and high electrical and thermal conductivity. We address the design and fabrication of a pillbox RF cavity with beryllium walls, in order to evaluate the performance of high-gradient cavities in strong magnetic fields.

  12. Fabrication of the prototype 201.25 mhz cavity for a muon ionization cooling experiment

    SciTech Connect

    Rimmer, R.A.; Manning, S.; Manus, R.; Phillips, L.; Stirbet, M.; Worland, K.; Wu, G.; Li, D.; MacGill, R.; Staples, J.; Virostek, S.; Zisman, M.S.; Taminger, K.; Hafley, R.; Martin, R.; Summers, D.; Reep, M.

    2005-05-20

    We describe the fabrication and assembly of the first prototype 201. 25 MHz copper cavity for the muon ionization cooling experiment (MICE). This cavity was developed by the US MUCOOL collaboration and will be tested in the new MUCOOL Test Area at Fermilab. We outline the component and subassembly fabrication steps and the various metal forming and joining methods used to produce the final cavity shape. These include spinning, brazing, TIG welding, electron beam welding, electron beam annealing and deep drawing. Some of the methods developed for this cavity are novel and offer significant cost savings over conventional methods.

  13. Fabrication of the Prototype 201.25 MHz Cavity for a Muon Ionization Cooling Experiment

    SciTech Connect

    R.A. Rimmer; S. Manning; R. Manus; L. Phillips; M. Stirbet; K. Worland; G. Wu; D. Li; R. MacGill; J. Staples; S. Virostek; M. Zisman; K. Taminger; R. Hafley; R. Martin; D. Summers; M. Reep

    2005-05-01

    We describe the fabrication and assembly of the first prototype 201.25 MHz copper cavity for the muon ionization cooling experiment (MICE). This cavity was developed by the US MUCOOL collaboration and will be tested in the new MUCOOL Test Area at Fermilab. We outline the component and subassembly fabrication steps and the various metal forming and joining methods used to produce the final cavity shape. These include spinning, brazing, TIG welding, electron beam welding, electron beam annealing and deep drawing. Some of the methods developed for this cavity are novel and offer significant cost savings over conventional construction methods.

  14. Epicyclic Twin-helix Magnetic Structure for Parametric-resonance Ionization Cooling

    SciTech Connect

    A. Afanasev, R.P. Johnson, Y.S. Derbenev, V.S. Morozov

    2010-05-01

    Para­met­ric-res­o­nance Ion­iza­tion Cool­ing (PIC) is en­vi­sioned as the final 6D cool­ing stage of a high-lu­mi­nos­i­ty muon col­lid­er. Im­ple­ment­ing PIC im­pos­es strin­gent con­straints on the cool­ing chan­nel's mag­net­ic op­tics de­sign. This paper pre­sents a lin­ear op­tics so­lu­tion com­pat­i­ble with PIC. Our so­lu­tion con­sists of a su­per­po­si­tion of two op­po­site-he­lic­i­ty equal-pe­ri­od and equal-strength he­li­cal dipole har­mon­ics and a straight nor­mal quadrupole. We demon­strate that such a sys­tem can be ad­just­ed to meet all of the PIC lin­ear op­tics re­quire­ments while re­tain­ing large ac­cep­tance.

  15. Color gradients in cooling flow cluster central galaxies and the ionization of cluster emission line systems

    NASA Technical Reports Server (NTRS)

    Romanishin, W.

    1988-01-01

    Preliminary results are given for a program to measure color gradients in the central galaxies in clusters with a variety of cooling flow rates. The objectives are to search for extended blue continuum regions indicative of star formation, to study the spatial distribution of star formation, and to make a quantitative measure of the amount of light from young stars, which can lead to a measure of the star formation rate (for an assumed initial mass function). Four clusters with large masses and large cluster H-alpha emission fluxes are found to have an excess of blue light concentrated to the centers of the cluster central galaxy. Assumption of a disk IMF leads to the conclusion that the starlight might play a major role in ionizing the emission line gas in these clusters.

  16. Resonant two-photon ionization spectroscopy of jet-cooled NiPt

    NASA Astrophysics Data System (ADS)

    Taylor, Scott; Spain, Eileen M.; Morse, Michael D.

    1990-03-01

    Resonant two-photon ionization spectroscopy of jet-cooled NiPt has been used to investigate the possibility of d-electron contributions to the bonding in this species. Based on an abrupt onset of predissociation, the bond strength of NiPt is assigned as D0(NiPt)=2.798±0.003 eV. Comparisons of scans using ArF (6.42 eV) or F2 (7.87 eV) radiation as the ionization laser yield IP(NiPt)=8.02±0.15 eV, from which we derive D0(Ni+-Pt)=2.41±0.15 eV and D0(Ni-Pt+) =3.58±0.35 eV. High resolution studies of the 6-0 and 8-0 bands of one of the three identifiable progressions demonstrate an Ω'=0←Ω`=0 transition with r'e =2.3396±0.0039Å and r″0 =2.2078±0.0023Å. The short bond length and large bond strength of NiPt, as compared to the corresponding values (re=2.330±0.003Å and D0=2.34±0.10 eV) for the coinage metal analog, CuAu, demonstrate significant d-orbital contributions to the bonding in NiPt.

  17. Parametric-Resonance Ionization Cooling and Reverse Emittance Exchange for Muon Colliders

    SciTech Connect

    Derbenev, Yaroslav; Johnson, Rolland P.

    2006-03-20

    Two new ideas are being developed to reduce the transverse emittance of muon beams in order to increase the luminosity of muon colliders. The first idea involves driving a (1/2)-integer parametric resonance in a beam line or ring such that particle motion becomes hyperbolic, where xx'=constant. With the proper phase of the resonance driving term, particles move to larger and larger x' and smaller and smaller x at the position of a thin wedge absorber. The usual mechanism of ionization cooling reduces or constrains the excursion in x' while the dynamics of the resonance reduces the spread of x. The second idea takes advantage of the large reduction of relative momentum spread with increasing momentum in going from a few hundred MeV/c where the beam is cooled to a few TeV/c for an energy frontier collider. In this case we can use thin wedge absorbers to exchange the transverse and longitudinal emittances to make the transverse emittance smaller. These two ideas depend on careful control of the lattice functions and corrections for chromatic and spherical aberrations. We discuss these ideas and their potential luminosity implications considering the limitations of aberration corrections and of space charge effects.

  18. Experimental assessment of on-chip liquid cooling through microchannels with de-ionized water and diluted ethylene glycol

    NASA Astrophysics Data System (ADS)

    Won, Yonghyun; Kim, Sungdong; Eunkyung Kim, Sarah

    2016-06-01

    Recent progress in Si IC devices, which results in an increase in power density and decrease in device size, poses various thermal challenges owing to high heat dissipation. Therefore, conventional cooling techniques become ineffective and produce a thermal bottleneck. In this study, an on-chip liquid cooling module with microchannels and through Si via (TSV) was fabricated, and cooling characteristics were evaluated by IR measurements. Both the microchannels and TSVs were fabricated in a Si wafer by deep reactive ion etching (DRIE) and the wafer was bonded with a glass wafer by a anodic bonding. The fabricated liquid cooling sample was evaluated using two different coolants (de-ionized water and 70 wt % diluted ethylene glycol), and the effect of coolants on cooling characteristics was investigated.

  19. The MICE Muon Beam on ISIS and the beam-line instrumentation of the Muon Ionization Cooling Experiment

    SciTech Connect

    Bogomilov, M.; et al.

    2012-05-01

    The international Muon Ionization Cooling Experiment (MICE), which is under construction at the Rutherford Appleton Laboratory (RAL), will demonstrate the principle of ionization cooling as a technique for the reduction of the phase-space volume occupied by a muon beam. Ionization cooling channels are required for the Neutrino Factory and the Muon Collider. MICE will evaluate in detail the performance of a single lattice cell of the Feasibility Study 2 cooling channel. The MICE Muon Beam has been constructed at the ISIS synchrotron at RAL, and in MICE Step I, it has been characterized using the MICE beam-instrumentation system. In this paper, the MICE Muon Beam and beam-line instrumentation are described. The muon rate is presented as a function of the beam loss generated by the MICE target dipping into the ISIS proton beam. For a 1 V signal from the ISIS beam-loss monitors downstream of our target we obtain a 30 KHz instantaneous muon rate, with a neglible pion contamination in the beam.

  20. The Effect of Extending the Length of the Coupling Coils in a MuonIonization Cooling Channel

    SciTech Connect

    Green, Michael A.

    2007-11-10

    RF cavities are used to re-accelerate muons that have beencooled by absorbers that are in low beta regions of a muon ionizationcooling channel. A superconducting coupling magnet (or magnets) arearound or among the RF cavities of a muon ionization-cooling channel. Thefield from the magnet guides the muons so that they are kept within theiris of the RF cavities that are used to accelerate the muons. Thisreport compares the use of a single short coupling magnet with anextended coupling magnet that has one or more superconducting coils aspart of a muon-cooling channel of the same design as the muon ionizationcooling experiment (MICE). Whether the superconducting magnet is shortand thick or long and this affects the magnet stored energy and the peakfield in the winding. The magnetic field distribution also affects is themuon beam optics in the cooling cell of a muon coolingchannel.

  1. OPTICAL SPECTROSCOPY OF H{alpha} FILAMENTS IN COOL CORE CLUSTERS: KINEMATICS, REDDENING, AND SOURCES OF IONIZATION

    SciTech Connect

    McDonald, Michael; Veilleux, Sylvain; Rupke, David S. N. E-mail: veilleux@astro.umd.edu

    2012-02-20

    We have obtained deep, high spatial and spectral resolution, long-slit spectra of the H{alpha} nebulae in the cool cores of nine galaxy clusters. This sample provides a wealth of information on the ionization state, kinematics, and reddening of the warm gas in the cool cores of galaxy clusters. We find evidence for only small amounts of reddening in the extended, line-emitting filaments, with the majority of filaments having E(B - V) < 0.2. We find, in agreement with previous works, that the optical emission in cool core clusters has elevated low-ionization line ratios. The combination of [O III]/H{beta}, [N II]/H{alpha}, [S II]/H{alpha}, and [O I]/H{alpha} allow us to rule out collisional ionization by cosmic rays, thermal conduction, and photoionization by intracluster medium (ICM) X-rays and active galactic nuclei as strong contributors to the ionization in the bulk of the optical line-emitting gas in both the nuclei and filaments. The data are adequately described by a composite model of slow shocks and star formation. This model is further supported by an observed correlation between the line widths and low-ionization line ratios which becomes stronger in systems with more modest star formation activity based on far-ultraviolet observations. We find that the more extended, narrow filaments tend to have shallower velocity gradients and narrower line widths than the compact filamentary complexes. We confirm that the widths of the emission lines decrease with radius, from FWHM {approx}600 km s{sup -1} in the nuclei to FWHM {approx}100 km s{sup -1} in the most extended filaments. The variation of line width with radius is vastly different than what is measured from stellar absorption lines in a typical giant elliptical galaxy, suggesting that the velocity width of the warm gas may in fact be linked to ICM turbulence and, thus, may provide a glimpse into the amount of turbulence in cool cores. In the central regions (r < 10 kpc) of several systems the warm gas

  2. 6D SCFTs and gravity

    NASA Astrophysics Data System (ADS)

    Del Zotto, Michele; Heckman, Jonathan J.; Morrison, David R.; Park, Daniel S.

    2015-06-01

    We study how to couple a 6D superconformal field theory (SCFT) to gravity. In F-theory, the models in question are obtained working on the supersymmetric background 5,1 × B where B is the base of a compact elliptically fibered Calabi-Yau threefold in which two-cycles have contracted to zero size. When the base has orbifold singularities, we find that the anomaly polynomial of the 6D SCFTs can be understood purely in terms of the intersection theory of fractional divisors: the anomaly coefficient vectors are identified with elements of the orbifold homology. This also explains why in certain cases, the SCFT can appear to contribute a "fraction of a hypermultiplet" to the anomaly polynomial. Quantization of the lattice of string charges also predicts the existence of additional light states beyond those captured by such fractional divisors. This amounts to a refinement to the lattice of divisors in the resolved geometry. We illustrate these general considerations with explicit examples, focusing on the case of F-theory on an elliptic Calabi-Yau threefold with base.

  3. The Lack of Influence of Metallicity on Cooling and Collapse of Ionized Gas in Small Protogalactic Halos

    NASA Astrophysics Data System (ADS)

    Jappsen, A.-K.; Glover, S. C. O.; Klessen, R. S.; Mac Low, M.-M.

    2005-12-01

    We study the influence of low levels of metal enrichment on the cooling and collapse of ionized gas in small protogalactic halos. We use three-dimensional, smoothed particle hydrodynamics simulations, run with the publicly available parallel code GADGET (Springel et al. 2001). We implement a sink particle algorithm. This allows us to safely represent gas that has collapsed beyond the resolution limit without causing numerical errors within the resolved regions of the simulation. We also include the necessary framework for following the non-equilibrium chemistry of H2 in the protogalactic gas, and a treatment of radiative heating and cooling. Our initial conditions represent protogalaxies forming within a fossil H ii region---a previously ionized H ii region that has not yet had time to cool and recombine. Prior to cosmological reionization, such regions should be relatively common, since the characteristic lifetimes of the likely ionizing sources are significantly shorter than a Hubble time. We show that in these regions, H2 is the dominant and most effective coolant, even in the presence of small amounts of metals. It is the amount of H2 which forms that controls whether or not the gas can collapse and form stars. For metallicities Z ≤ 10-3 Z⊙, we find that metal line cooling alters the density and temperature evolution of the gas by less than 1% compared to the metal-free case at densities below 1 cm-3 and temperatures above 2000 K. However, at higher densities and lower temperatures, metal line cooling does become rather more important, and will affect the ability of the gas to fragment. We also show that an external ultraviolet background delays or suppresses the cooling and collapse of the gas regardless of whether or not it is metal-enriched. RSK and A-KJ acknowledge support from the Emmy Noether Program of the Deutsche Forschungsgemeinschaft (grant no. KL1358/1). M-MML acknowledges support from NSF grants AST99-85392 and AST03-07854, and NASA grant NAG5

  4. Recent Innovations in Muon Beam Cooling

    SciTech Connect

    Johnson, Rolland P.; Alsharo'a, Mohammad; Hanlet, Pierrick M.; Hartline, Robert; Kuchnir, Moyses; Paul, Kevin; Roberts, Thomas J.; Ankenbrandt, Charles; Barzi, Emanuela; Del Frate, Licia; Gonin, Ivan; Moretti, Alfred; Neuffer, David; Popovic, Milorad; Romanov, Gennady; Turrioni, Daniele; Yarba, Victor; Beard, Kevin; Bogacz, S. Alex; Derbenev, Yaroslav

    2006-03-20

    Eight new ideas are being developed under SBIR/STTR grants to cool muon beams for colliders, neutrino factories, and muon experiments. Analytical and simulation studies have confirmed that a six-dimensional (6D) cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas can provide effective beam cooling. This helical cooling channel (HCC) has solenoidal, helical dipole, helical quadrupole, and helical sextupole magnetic fields to generate emittance exchange and achieve 6D emittance reduction of over 3 orders of magnitude in a 100 m segment. Four such sequential HCC segments, where the RF frequencies are increased and transverse physical dimensions reduced as the beams become cooler, implies a 6D emittance reduction of almost five orders of magnitude. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, then can be employed to reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that can be used as MANX, an exceptional 6D cooling demonstration experiment.

  5. Recent Innovations in Muon Beam Cooling

    SciTech Connect

    Rolland P. Johnson; Mohammad Alsharo'a; Charles Ankenbrandt; Emanuela Barzi; Kevin Beard; S. Alex Bogacz; Yaroslav Derbenev; Licia Del Frate; Ivan Gonin; Pierrick M. Hanlet; Robert Hartline; Daniel M. Kaplan; Moyses Kuchnir; Alfred Moretti; David Neuffer; Kevin Paul; Milorad Popovic; Thomas J. Roberts; Gennady Romanov; Daniele Turrioni; Victor Yarba; and Katsuya Yonehara

    2006-03-01

    Eight new ideas are being developed under SBIR/STTR grants to cool muon beams for colliders, neutrino factories, and muon experiments. Analytical and simulation studies have confirmed that a six-dimensional (6D) cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas can provide effective beam cooling. This helical cooling channel (HCC) has solenoidal, helical dipole, helical quadrupole, and helical sextupole magnetic fields to generate emittance exchange and achieve 6D emittance reduction of over 3 orders of magnitude in a 100 m segment. Four such sequential HCC segments, where the RF frequencies are increased and transverse physical dimensions reduced as the beams become cooler, implies a 6D emittance reduction of almost five orders of magnitude. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, then can be employed to reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that can be used as MANX, an exceptional 6D cooling demonstration experiment.

  6. Threshold ionization spectroscopic investigation of supersonic jet-cooled, laser-desorbed Tryptophan

    NASA Astrophysics Data System (ADS)

    Taherkhani, Mehran; Armentano, Antonio; Černý, Jiří; Müller-Dethlefs, Klaus

    2016-07-01

    Tryptophan (Trp) was studied by two-colour Photoionization Efficiency (PIE) and Mass Analysed Threshold Ionization (MATI) spectroscopy using a laser desorption apparatus. Conformer A of Trp was excited into the S1 state (34,878 cm-1) and the second laser was scanned around the D0 cation ground and the D1 excited state. No ionization signal into the D0 state could be found, but a clear threshold was observed for the D1 state with an ionization energy of 66,704 ± 3 cm-1 (8.27 eV). This observation is explained in terms of the electronic configurations of the S1 and cationic states.

  7. Advances in Beam Cooling for Muon Colliders

    SciTech Connect

    R.P. Johnson, Y.S. Derbenev

    2006-09-01

    A six-dimensional (6D) ionization cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas is the basis for the latest plans for muon colliders. This helical cooling channel (HCC) has solenoidal, helical dipole, and helical quadrupole magnetic fields, where emittance exchange is achieved by using a continuous homogeneous absorber. Momentum-dependent path length differences in the dense hydrogen energy absorber provide the required correlation between momentum and ionization loss to accomplish longitudinal cooling. Recent studies of an 800 MHz RF cavity pressurized with hydrogen, as would be used in this application, show that the maximum gradient is not limited by a large external magnetic field, unlike vacuum cavities. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, will be employed to further reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that is being developed for an exceptional 6D cooling demonstration experiment. The status of the designs, simulations, and tests of the cooling components for a high luminosity, low emittance muon collider will be reviewed.

  8. Ionization and excitation in cool giant stars. I - Hydrogen and helium

    NASA Technical Reports Server (NTRS)

    Luttermoser, Donald G.; Johnson, Hollis R.

    1992-01-01

    The influence that non-LTE radiative transfer has on the electron density, ionization equilibrium, and excitation equilibrium in model atmospheres representative of both oxygen-rich and carbon-rich red giant stars is demonstrated. The radiative transfer and statistical equilibrium equations are solved self-consistently for H, H(-), H2, He I, C I, C II, Na I, Mg I, Mg II, Ca I, and Ca II in a plane-parallel static medium. Calculations are made for both radiative-equilibrium model photospheres alone and model photospheres with attached chromospheric models as determined semiempirically with IUE spectra of g Her (M6 III) and TX Psc (C6, 2). The excitation and ionization results for hydrogen and helium are reported.

  9. Spectroscopy of Jet-Cooled Neutral and Ionized PAHs: Implications for Interstellar Dust

    NASA Technical Reports Server (NTRS)

    Salama, F.; Tan, X.; Biennier, L.; Cami, J.

    2005-01-01

    We present the gas-phase spectroscopy of neutral and ionized polycyclic aromatic hydrocarbons (PAHs) measured in the W-Visible-NIR range in an astrophysically relevant environment. These measurements provide data on PAHs and nanometer sized particles that can now be directly compared to astronomical observations. The harsh physical conditions of the IS medium - characterized by a low temperature, an absence of collisions and strong VUV radiation fields - are simulated in the laborat'ory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions are formed from the neutral precursors in an isolated environment at low temperature ($\\sim lOO$-K). The spectra of neutral and ionized PAHs are measured using the high sensitivity methods of cavity ring down spectroscopy (CRDS) and multiplex integrated cavity output spectroscopy (MICOS). These experiments provide unique information on the spectra of free, cold large carbon molecules and ions in the gas phase. The electronic bands measured for ionized PAH are found to be intrinsically broad ($\\geq$20 cm$^{-l}$) while the bands associated with the neutral precursors are narrower (of the order of 2 - 10 cm$^{-l}$). The laboratory data are discussed and compared with recent astronomical spectra of large and narrow DIBs and with the spectra of circumstellar environments of selected carbon stars (see contribution of Cami et al.) and the implications for the interstellar PAH population are derived. Preliminary results also show that carbon nanoparticles are formed during the short residence time of the precursors in the plasma. This finding holds great potential for understanding the formation process of interstellar grains.

  10. The MANX Muon Cooling Experiment Detection System

    SciTech Connect

    Kahn, S. A.; Abrams, R. J.; Ankenbrandt, C.; Cummings, M. A. C.; Johnson, R. P.; Robertsa, T. J.; Yoneharab, K.

    2010-03-30

    The MANX experiment is being proposed to demonstrate the reduction of 6D muon phase space emittance, using a continuous liquid absorber to provide ionization cooling in a helical solenoid magnetic channel. The experiment involves the construction of a two-period-long helical cooling channel (HCC) to reduce the muon invariant emittance by a factor of two. The HCC would replace the current cooling section of the MICE experiment now being set up at the Rutherford Appleton Laboratory. The MANX experiment would use the existing MICE spectrometers and muon beam line. We discuss the placement of detection planes to optimize the muon track resolution.

  11. The integrated radio continuum spectrum of M33 - Evidence for free-free absorption by cool ionized gas

    NASA Technical Reports Server (NTRS)

    Israel, F. P.; Mahoney, M. J.; Howarth, N.

    1992-01-01

    We present measurements of the integrated radio continuum flux density of M33 at frequencies between 22 and 610 MHz and discuss the radio continuum spectrum of M33 between 22 MHz and 10 GHz. This spectrum has a turnover between 500 and 900 MHz, depending on the steepness of the high frequency radio spectrum of M33. Below 500 MHz the spectrum is relatively flat. We discuss possible mechanisms to explain this spectral shape and consider efficient free-free absorption of nonthermal emission by a cool (not greater than 1000 K) ionized gas to be a very likely possibility. The surface filling factor of both the nonthermal and the thermal material appears to be small (of order 0.001), which could be explained by magnetic field/density fluctuations in the M 33 interstellar medium. We briefly speculate on the possible presence of a nuclear radio source with a steep spectrum.

  12. IONIZED ABSORBERS AS EVIDENCE FOR SUPERNOVA-DRIVEN COOLING OF THE LOWER GALACTIC CORONA

    SciTech Connect

    Fraternali, Filippo; Marasco, Antonino; Binney, James

    2013-02-20

    We show that the ultraviolet absorption features, newly discovered in Hubble Space Telescope spectra, are consistent with being formed in a layer that extends a few kpc above the disk of the Milky Way. In this interface between the disk and the Galactic corona, high-metallicity gas ejected from the disk by supernova feedback can mix efficiently with the virial-temperature coronal material. The mixing process triggers the cooling of the lower corona down to temperatures encompassing the characteristic range of the observed absorption features, producing a net supernova-driven gas accretion onto the disk at a rate of a few M{sub Sun} yr{sup -1}. We speculate that this mechanism explains how the hot mode of cosmological accretion feeds star formation in galactic disks.

  13. Twistor form of massive 6D superparticle

    NASA Astrophysics Data System (ADS)

    Routh, Alasdair J.; Townsend, Paul K.

    2016-01-01

    The massive six-dimensional (6D) superparticle with manifest (n, 0) supersymmetry is shown to have a supertwistor formulation in which its ‘hidden’ (0, n) supersymmetry is also manifest. The mass-shell constraint is replaced by Spin(5) spin-shell constraints which imply that the quantum superparticle has zero superspin; for n = 1 it propagates the 6D Proca supermultiplet.

  14. Methods of beam cooling

    SciTech Connect

    Sessler, A.M.

    1996-02-01

    Diverse methods which are available for particle beam cooling are reviewed. They consist of some highly developed techniques such as radiation damping, electron cooling, stochastic cooling and the more recently developed, laser cooling. Methods which have been theoretically developed, but not yet achieved experimentally, are also reviewed. They consist of ionization cooling, laser cooling in three dimensions and stimulated radiation cooling.

  15. Muon Beam Helical Cooling Channel Design

    SciTech Connect

    Johnson, Rolland; Ankenbrandt, Charles; Flanagan, G; Kazakevich, G M; Marhauser, Frank; Neubauer, Michael; Roberts, T; Yoshikawa, C; Derbenev, Yaroslav; Morozov, Vasiliy; Kashikhin, V S; Lopes, Mattlock; Tollestrup, A; Yonehara, Katsuya; Zloblin, A

    2013-06-01

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet.

  16. Influence of plasma loading in a hybrid muon cooling channel

    SciTech Connect

    Freemire, B.; Stratakis, D.; Yonehara, K.

    2015-05-03

    In a hybrid 6D cooling channel, cooling is accomplished by reducing the beam momentum through ionization energy loss in wedge absorbers and replenishing the momentum loss in the longitudinal direction with gas-filled rf cavities. While the gas acts as a buffer to prevent rf breakdown, gas ionization also occurs as the beam passes through the pressurized cavity. The resulting plasma may gain substantial energy from the rf electric field which it can transfer via collisions to the gas, an effect known as plasma loading. In this paper, we investigate the influence of plasma loading on the cooling performance of a rectilinear hybrid channel. With the aid of numerical simulations we examine the sensitivity in cooling performance and plasma loading to key parameters such as the rf gradient and gas pressure.

  17. Resonance Enhanced Multi-Photon Ionization and Uv-Uv Hole-Burning Spectroscopic Studies of Jet-Cooled Acetanilide Derivatives

    NASA Astrophysics Data System (ADS)

    Moon, Ceol Joo; Min, Ahreum; Ahn, Ahreum; Lee, Seung Jun; Choi, Myong Yong; Kim, Seong Keun

    2013-06-01

    Conformational investigations and photochemistry of jet-cooled methacetine (MA) and phenacetine (PA) using one color resonant two-photon ionization (REMPI), UV-UV hole-burning and IR-dip spectroscopy are presented. MA and PA are derivatives of acetanilide, substituted by methoxyl, ethoxyl group in the para position of acetanilide, respectively. Moreover, we have investigated conformational information of the acetanilide derivatives (AAP, MA and PA)-water. In this work, we will present and discuss the solvent effects of the hydroxyl group of acetanilide derivatives in the excited state.

  18. Helical Muon Beam Cooling Channel Engineering Design

    SciTech Connect

    Kashikhin, V.S.; Lopes, M.L.; Romanov, G.V.; Tartaglia, M.A.; Yonehara, K.; Yu, M.; Zlobin, A.V.; Flanagan, G.; Johnson, R.P.; Kazakevich, G.M.; Marhauser, F.; /MUONS Inc., Batavia

    2012-05-01

    The Helical Cooling Channel (HCC), a novel technique for six-dimensional (6D) ionization cooling of muon beams, has shown considerable promise based on analytic and simulation studies. However, the implementation of this revolutionary method of muon cooling requires new techniques for the integration of hydrogen-pressurized, high-power RF cavities into the low-temperature superconducting magnets of the HCC. We present the progress toward a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb{sub 3}Sn based HCC test section. We include discussions on the pressure and thermal barriers needed within the cryostat to maintain operation of the magnet at 4.2 K while operating the RF and energy absorber at a higher temperature. Additionally, we include progress on the Nb{sub 3}Sn helical solenoid design.

  19. A fitting formula for radiative cooling based on non-local thermodynamic equilibrium population from weakly-ionized air plasma

    NASA Astrophysics Data System (ADS)

    Ogino, Yousuke; Nagano, Atsushi; Ishihara, Tomoaki; Ohnishi, Naofumi

    2013-08-01

    A fitting formula for radiative cooling with collisional-radiative population for air plasma flowfield has been developed. Population number densities are calculated from rate equations in order to evaluate the effects of nonequilibrium atomic and molecular processes. Many elementary processes are integrated to be applied to optically-thin plasmas in the number density range of 1012/cm3 <= N <= 1019/cm3 and the temperature range of 300 K <= T <= 40,000 K. Our results of the total radiative emissivity calculated from the collisional-radiative population are fitted in terms of temperature and total number density. To validate the analytic fitting formula, numerical simulation of a laser-induced blast wave propagation with the nonequilibrium radiative cooling is conducted and successfully reproduces the shock and plasma wave front time history observed by experiments. In addition, from the comparison between numerical simulations with the radiation cooling effect based on the fitting formula and those with a gray gas radiation model that assumes local thermodynamic equilibrium, we find that the displacement of the plasma front is slightly different due to the deviation of population probabilities. By using the fitting formula, we can easily and more accurately evaluate the radiative cooling effect without solving detailed collisional-radiative rate equations.

  20. HuDo 1 and HuBi 1: two planetary nebulae ionized by cool [WC] central stars

    NASA Astrophysics Data System (ADS)

    Peña, M.

    2005-10-01

    As part of our spectroscopic survey of planetary nebulae with [WC] nuclei (Peña et al. 2001), low- and high-resolution spectra of the planetary nebulae HuDo 1 (PNG 060.4+01.5, PM1-310) and HuBi 1 (PNG 012.2+04.9, PM1-188) were secured and analyzed. Both objects are ionized by very late [WC] central stars. We found that the objects belong to the galactic disk, with heliocentric radial velocities of -12 km s-1 (HuDo 1) and 57 km s-1 (HuBi1). Both objects are heavily extinguished showing a logarithmic reddening, c(Hβ), of 2.04 for HuDo 1 and 1.22 for HuBi 1. Our data cover a wide wavelength range; therefore we obtained several plasma line ratios to estimate physical conditions and abundances. The derived electron temperature and density for HuBi 1 are 9,400±1,500 K and 800 cm-3. This density is very low for a nebula around a [WC]-late star. HuDo 1 has Ne = 3300 cm-3. We find log(O/H)+12 = 8.43 and 8.57, and N/O = 0.2 and 0.1 for HuDo 1 and HuBi 1 respectively, typical of disk PNe. Intense nebular He I recombination lines are detected for HuBi 1, this being the only PN excited by a very late [WC] star showing such an emission. The He+ abundance derived for HuBi 1 is 0.11, which is indicating a large He enhancement in HuBi 1. >From the analysis of the stellar emission lines a [WC 10] spectral type is derived for both stars. This is consistent with a stellar temperature of about 30,000 K, although the HuBi 1 central star should be slightly hotter for providing the large amount of He0 ionizing photons required to explain the nebular He I lines. Nebular and stellar parameters of HuDo 1 and HuBi 1 can be compared with those of other [WC 10] objects, such as M 4-18, He 2-113 and CPD-5608031. >From this, we can conclude that, in spite of the fact that all the objects have the same spectral type, the central stars of HuDo 1 and HuBi 1 should be intrinsically fainter, and consequently of lower mass. This is an additional evidence showing that stars of different masses can go

  1. Charge Separation for Muon Collider Cooling

    SciTech Connect

    Palmer, R.B.; Fernow; R.C.

    2011-03-28

    Most schemes for six dimensional muon ionization cooling work for only one sign. It is then necessary to have charge separation prior to that cooling. Schemes of charge separation using bent solenoids are described, and their simulated performances reported. It is found that for efficient separation, it should take place at somewhat higher momenta than commonly used for the cooling. Charge separation using bent solenoids can be effective if carefully designed. Bent solenoids can generate dispersion from 'momentum drift', but can spoil emittance from 'amplitude drift'. Abrupt entry into a bent solenoid causes emittance growth, but matching using integral {lambda} lengths, or Norem's method, corrects this problem. Reverse bending removes the dispersion and reduces 'amplitude drift', but only if there is no rf until after all bending. The main problem is bunch lengthening and distortion from the long transports without rf. At 230 MeV/c, even with a higher field of 3 T, non-linearities increase the 6D emittance by 117% and give 13% loss, which is not acceptable. Raising the momentum from 230 to 300 MeV gives a 6D emittance growth of 38% and the loss 5%, which may be acceptable. Raising the momentum further to 400 MeV/c gives very good results: 6D growth of 24% and 2.5% loss. Further optimization should include the acceleration to the higher momenta prior to the separation, and the higher momentum cooling immediately after it. The longitudinal phase space prior to the separation should be rotated to minimize the total bunch lengthening.

  2. Design Issues for the Superconducting Magnet that Goes Around theLiquid Hydrogen Absorber for the Muon Ionization Cooling Experiment(MICE)

    SciTech Connect

    Barr, G.; Cobb, J.H.; Green, M.A.; Lau, W.; Senanayake R.S.; Yang, S.Q.; Baynham, D.E.; Bradshaw, T.W.; Drum, P.V.; Rochford, J.H.; Chilton, Didcot

    2004-06-15

    This report describes the design issues that are associated with a superconducting focusing solenoid that goes around a liquid hydrogen absorber for the Muon Ionization Cooling Experiment (MICE) proposed for the Rutherford Appleton Laboratory. The solenoid consists of two superconducting coils that may operated at the same polarity or at opposite polarities. As a result, the coils and their support structure must be designed to carry a 360-ton inter-coil force that is forcing the coils apart along their axis. The basic design parameters for the focusing magnet are discussed. The magnet and its cryostat are designed so that the absorber can be assembled and tested before installation into the pre-tested focusing solenoid. Safety requirements for MICE dictate that the insulating vacuum for the superconducting magnet be separated from the insulating vacuum for the absorber and that both vacuum be separated from the experiment vacuum and the vacuum within adjacent RF cavities. The safety issues associated with the arrangement of the various vacuums in the MICE focusing modules are presented. The effect of magnet operation and magnet quench on the liquid hydrogen absorber is also discussed.

  3. Infrared Spectroscopy of C_6D_6-Rg_n(n=1,2)

    NASA Astrophysics Data System (ADS)

    George, Jobin; Yousefi, Mahdi; Rezaei, Mojtaba; McKellar, Bob; Moazzen-Ahmadi, Nasser

    2014-06-01

    Benzene-noble gas complexes were one of the earliest topics of interest in spectroscopic investigation of van der Waals (vdW) complexes. Smalley et al. observed C_6H_6-(He)1,2 vdW complexes in the late 1970s by means of electronic spectroscopy. A recent study on the same species was done by M. Hayashi et al. Here, we present the infrared observation of C_6D_6-Rg_n (n=1,2) with the rare gas being He, Ne, or Ar, in the regions of νb{12} fundamental band of C_6D_6 (˜2289 wn) and the νb{2} + νb{13} combination band (˜2275 wn) which are coupled by a Fermi resonance. The spectra were observed at a resolution of 60 MHz using a tunable optical parametric oscillator to probe a pulsed supersonic-jet expansion from a slit nozzle. In the case of C_6D_6-Rg dimers, the spectra were assigned to a symmetric top with C6v symmetry with the rare gas atom being located on the C6 symmetry axis. To observe C_6D_6-Rg_2 trimers, the nozzle was cooled using a closed-cycle methanol refrigerator and the spectra were simulated with a rotational temperature of 1.3K. The spectra of the C_6D_6-Rg_2 trimers were in agreement with a D6h symmetry structure, where the rare gas atoms are positioned above and below the C_6D_6 plane. Data analysis and observation are presently ongoing. S. M. Beck, M. G. Liverman, D. L. Monts and R. E. Smalley, J. Chem. Phys. 70, 232 (1979). M. Hayashi, Y. Ohshima, Chem. Phys. 419, 131 (2013).

  4. On the Defect Group of a 6D SCFT

    NASA Astrophysics Data System (ADS)

    Del Zotto, Michele; Heckman, Jonathan J.; Park, Daniel S.; Rudelius, Tom

    2016-04-01

    We use the F-theory realization of 6D superconformal field theories (SCFTs) to study the corresponding spectrum of stringlike, i.e., surface defects. On the tensor branch, all of the stringlike excitations pick up a finite tension, and there is a corresponding lattice of string charges, as well as a dual lattice of charges for the surface defects. The defect group is data intrinsic to the SCFT and measures the surface defect charges which are not screened by dynamical strings. When non-trivial, it indicates that the associated theory has a partition vector rather than a partition function. We compute the defect group for all known 6D SCFTs, and find that it is just the abelianization of the discrete subgroup of U(2) which appears in the classification of 6D SCFTs realized in F-theory. We also explain how the defect group specifies defining data in the compactification of a (1, 0) SCFT.

  5. On the Defect Group of a 6D SCFT

    NASA Astrophysics Data System (ADS)

    Del Zotto, Michele; Heckman, Jonathan J.; Park, Daniel S.; Rudelius, Tom

    2016-06-01

    We use the F-theory realization of 6D superconformal field theories (SCFTs) to study the corresponding spectrum of stringlike, i.e., surface defects. On the tensor branch, all of the stringlike excitations pick up a finite tension, and there is a corresponding lattice of string charges, as well as a dual lattice of charges for the surface defects. The defect group is data intrinsic to the SCFT and measures the surface defect charges which are not screened by dynamical strings. When non-trivial, it indicates that the associated theory has a partition vector rather than a partition function. We compute the defect group for all known 6D SCFTs, and find that it is just the abelianization of the discrete subgroup of U(2) which appears in the classification of 6D SCFTs realized in F-theory. We also explain how the defect group specifies defining data in the compactification of a (1, 0) SCFT.

  6. Conformal anomaly c-coefficients of superconformal 6d theories

    NASA Astrophysics Data System (ADS)

    Beccaria, Matteo; Tseytlin, Arkady A.

    2016-01-01

    We propose general relations between the conformal anomaly and the chiral (R-symmetry and gravitational) anomaly coefficients in 6d (1, 0) superconformal theories. The suggested expressions for the three type B conformal anomaly c i -coefficients complement the expression for the type A anomaly a-coefficient found in arXiv:1506.03807. We check them on several examples — the standard (1, 0) hyper and tensor multiplets as well as some higher derivative short multiplets containing vector fields that generalize the super-conformal 6d vector multiplet discussed in arXiv:1506.08727. We also consider a family of higher derivative superconformal (2, 0) 6d multiplets associated to 7d multiplets in the KK spectrum of 11d supergravity compactified on S 4. In particular, we prove that (2,0) 6d conformal supergravity coupled to 26 tensor multiplets is free of all chiral and conformal anomalies. We discuss some interacting (1, 0) superconformal theories, predicting the c i -coefficients for the "E-string" theory on multiple M5-branes at E 8 9-brane and for the theory describing M5-branes at an orbifold singularity {C}^2/Γ . Finally, we elaborate on holographic computation of subleading corrections to conformal anomaly coefficients coming from R 2 + R 3 terms in 7d effective action, revisiting, in particular, the (2,0) theory case.

  7. Modified Elliptic Gamma Functions and 6d Superconformal Indices

    NASA Astrophysics Data System (ADS)

    Spiridonov, Vyacheslav P.

    2014-04-01

    We construct a modified double elliptic gamma function which is well defined when one of the base parameters lies on the unit circle. A model consisting of 6d hypermultiplets coupled to a gauge field theory living on a 4d defect is proposed whose superconformal index uses the double elliptic gamma function and obeys W( E 7)-group symmetry.

  8. Experimental Tests of Cooling: Expectations and Additional Needs

    SciTech Connect

    Zisman, Michael S

    2008-09-24

    Cooling is a critical aspect for a high-performance Neutrino Factory or a MuonCollider. For this reason, considerable effort is being put toward theexperimental verification of this technique. The international Muon IonizationCooling Experiment, MICE, was approved to operate at Rutherford AppletonLaboratory (RAL) in the UK and beam line commissioning commenced in March, 2008. The MICE collaboration comprises about 130 scientists and engineers from Asia, Europe, and the U.S. In this paper we present the motivation and goals for thisexperiment and describe its present status. MICE is scheduled for completion in2011. We will also indicate the prospects for a future 6D muon coolingexperiment and discuss its possible time schedule.

  9. CF6-6D engine performance deterioration

    NASA Technical Reports Server (NTRS)

    Wulf, R. H.; Kramer, W. H.; Pass, J. E.; Smith, J. J.

    1980-01-01

    Cruise cockpit recordings and test cell performance data in conjunction with hardware inspection data from airline overhaul shops were analyzed to define the extent and magnitude of performance deterioration of the General Electric CF6-6D model engine. These studies successfully isolated short-term deterioration from the longer term, and defined areas where a significant reduction in aircraft energy requirements for the 1980's can be realized. Unrestored losses which remain after engine refurbishment represent over 70% of the loss at engine shop visit. Sixty-three percent of the unrestored losses are cost-effective to restore which could reduce fuel consumed by CF6-6D engines in 1980 by 10.9 million gallons.

  10. Evidence for C-theorems in 6D SCFTs

    NASA Astrophysics Data System (ADS)

    Heckman, Jonathan J.; Rudelius, Tom

    2015-09-01

    Using the recently established classification of 6D SCFTs we present evidence for the existence of families of weak C-functions, that is, quantities which decrease in a flow from the UV to the IR. Introducing a background R-symmetry field strength R, and a non-trivial tangent bundle T on the 6D spacetime, we consider C-functions given by the linear combinations C = m 1α + m 2 β + m 3γ, where the αi are the anomaly polynomial coefficients for the formal characteristic classes c 2( R)2, c 2( R) p 1( T ) and p 1( T )2. By performing a detailed sweep over many theories, we determine the shape of the unbounded region in " m-space" compatible with both Higgs branch flows and tensor branch flows. We also verify that — as expected — the Euler density conformal anomaly falls in the admissible region.

  11. The Simpsons program 6-D phase space tracking with acceleration

    NASA Astrophysics Data System (ADS)

    Machida, S.

    1993-12-01

    A particle tracking code, Simpsons, in 6-D phase space including energy ramping has been developed to model proton synchrotrons and storage rings. We take time as the independent variable to change machine parameters and diagnose beam quality in a quite similar way as real machines, unlike existing tracking codes for synchrotrons which advance a particle element by element. Arbitrary energy ramping and rf voltage curves as a function of time are read as an input file for defining a machine cycle. The code is used to study beam dynamics with time dependent parameters. Some of the examples from simulations of the Superconducting Super Collider (SSC) boosters are shown.

  12. Final Technical Report on STTR Project DE-FG02-02ER86145 Pressurized RF Cavities for Muon Ionization Cooling

    SciTech Connect

    Rolland Johnson

    2006-07-13

    This project was to design and build an RF test cell (TC), which could be operated at 800 MHz, filled with high pressure gases including hydrogen, at temperatures down to that of liquid nitrogen, in strong magnetic fields, in a strong radiation environment, and with interchangeable electrodes, in order to examine the use of high-pressure RF cavities for muon beam cooling.

  13. 17 CFR 270.6d-1 - Exemption for certain closed-end investment companies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...-end investment companies. 270.6d-1 Section 270.6d-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.6d-1 Exemption for certain closed-end investment companies. (a) An application under section 6(d) of the Act...

  14. 17 CFR 270.6d-1 - Exemption for certain closed-end investment companies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...-end investment companies. 270.6d-1 Section 270.6d-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.6d-1 Exemption for certain closed-end investment companies. (a) An application under section 6(d) of the Act...

  15. 17 CFR 270.6d-1 - Exemption for certain closed-end investment companies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...-end investment companies. 270.6d-1 Section 270.6d-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.6d-1 Exemption for certain closed-end investment companies. (a) An application under section 6(d) of the Act...

  16. 17 CFR 270.6d-1 - Exemption for certain closed-end investment companies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...-end investment companies. 270.6d-1 Section 270.6d-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.6d-1 Exemption for certain closed-end investment companies. (a) An application under section 6(d) of the Act...

  17. 17 CFR 270.6d-1 - Exemption for certain closed-end investment companies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...-end investment companies. 270.6d-1 Section 270.6d-1 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT COMPANY ACT OF 1940 § 270.6d-1 Exemption for certain closed-end investment companies. (a) An application under section 6(d) of the Act...

  18. μ term and supersymmetry breaking from 6D theory

    NASA Astrophysics Data System (ADS)

    Adachi, Yuki; Haba, Naoyuki; Yamashita, Toshifumi

    2014-06-01

    We propose a new next-to-minimal supersymmetric standard model (NMSSM), which is on a 6D spacetime compactified on a T^2/Z_3 orbifold. In this model, three gauge singlet fields N, S_1, and S_2 in addition to the minimal supersymmetric standard model (MSSM) fields are introduced. These fields are localized at some fixed points, except for the singlet N and the gauge fields. The μ parameter is provided from the vacuum expectation value (VEV) of N. The F terms get VEVs simultaneously, and the gauginos mediate the supersymmetry breaking to the MSSM sector. Both of these parameters are strongly suppressed due to the profile of N. Thus, these parameters, induced from those on the order of the so-called Grand Unified Theory (GUT) scale, can become close to the electroweak scale without unnatural fine tuning.

  19. 6D electron beam diagnostics at SPARC_LAB

    NASA Astrophysics Data System (ADS)

    Cianchi, A.; Anania, M. P.; Bacci, A.; Bellaveglia, Marco; Castellano, Michele; Chiadroni, Enrica; Di Giovenale, Domenico; Di Pirro, Giampiero; Ferrario, Massimo; Innocenti, Luca; Mostacci, Andrea; Pompili, Riccardo; Rossi, A. R.; Shpakov, V.; Vaccarezza, Cristina; Villa, Fabio

    2015-05-01

    To create very short electron bunches or comb-like beams, able to drive a SASE-FEL, to produce THz radiation, or to drive a plasma beam driven accelerator is needed advanced phase space manipulation. The characterization of the 6D phase space is of paramount importance in order to verify that the beam parameters fulfill the expectation. At SPARCLAB we have integrated several longitudinal and transverse beam diagnostics for single bunch or for a train of comb-like bunches at THz repetition rate. Longitudinal diagnostic is based on RF deflecting cavity and a dispersive element. Quadrupole scan technique is used to measure the transverse emittance in single bunch mode or in conjunction respectively with a dipole, to separate beams of different energy, and RF deflector, to discriminates bunches with different time of arrival.

  20. Full 6-D characterization of ship motion using GPS & INS

    NASA Astrophysics Data System (ADS)

    Thomsen, D. R.; Chadwell, C. D.; Sandwell, D. T.

    2005-12-01

    Full characterization of the motion of a ship is required for various oceanographic and engineering activities including marine geodetic surveys [Chadwell and Bock, 2001; Chadwell et al., 1995; Spiess et al., 1998], synthetic aperture sonar processing [Asada and Yabuki, 2001] and instrument calibration. Reconstruction of the ship-position requires knowledge of both the motions of the center of the coordinate system of the ship and the roll, pitch and yaw of the ship about the center. The feasibility of 1 Hz. sampled 3-D ship position measurements at centimeter-scale resolution using a triad of precisely positioned kinematic GPS receivers has been demonstrated [Chadwell, 2003; Chadwell and Bock, 2001]. Additionally, there exists onboard inertial navigation system (INS) instrumentation measuring pitch, yaw, and roll of the ship in the forms of a PHINS strapdown package. These data have a nominal sample interval of 10 Hz. Used together, the 1 Hz GPS position measurements and the 10 Hz angular and inertial measurements provide a good estimate of the full 6-D ship motion. As the characterization is completed in the post-processing, the position estimation at any point in time can utilize data both preceding and postdating that time rather than being limited by a forward predictive filter set such as is traditionally used in INS/GPS integration. We discuss the integration of the two datasets and the expected accuracy of the final integrated set. We further demonstrate the adaptation and limitations of using a single GPS receiver combined with the inertial and unfiltered angular measurements to predict the full 6-D ship motion. We briefly describe the theory of motion reconstruction and the techniques used to recover the full ship motion using first the combination of the three-GPS and INS data and later the one-GPS/INS integration.

  1. Flavour changing Z ' signals in a 6D inspired model

    NASA Astrophysics Data System (ADS)

    Frère, Jean-Marie; Libanov, Maxim; Mollet, Simon; Troitsky, Sergey

    2016-06-01

    We consider the phenomenology of new neutral gauge bosons with flavour non-diagonal couplings to fermions, inherent in 6D models explaining successfully the hierarchy of masses as well as the mixing for quarks, charged leptons and neutrinos (this model can in particular be credited with the correct prediction of the neutrino mixing angle θ 13). We present a general relation between masses of new gauge bosons and their couplings to fermions. We show that in the current realization of the model, the new heavy bosons are unreachable at LHC but argue why the constraint could be relaxed in the context of a different realization. In view of a more systematic study, we use an effective model inspired by the above to relate directly rare meson decays to possible LHC observations. In terms of effective Lagrangians, this can be seen as the introduction in the model of only one overall scaling parameter to extend our approach without modifying the 4D (gauge) structure.

  2. Helical muon beam cooling channel engineering design

    SciTech Connect

    Johnson, Rolland

    2015-08-07

    The Helical Cooling Channel (HCC) achieves effective ionization cooling of the six-dimensional (6d) phase space of a muon beam by means of a series of 21st century inventions. In the HCC, hydrogen-pressurized RF cavities enable high RF gradients in strong external magnetic fields. The theory of the HCC, which requires a magnetic field with solenoid, helical dipole, and helical quadrupole components, demonstrates that dispersion in the gaseous hydrogen energy absorber provides effective emittance exchange to enable longitudinal ionization cooling. The 10-year development of a practical implementation of a muon-beam cooling device has involved a series of technical innovations and experiments that imply that an HCC of less than 300 m length can cool the 6d emittance of a muon beam by six orders of magnitude. We describe the design and construction plans for a prototype HCC module based on oxygen-doped hydrogen-pressurized RF cavities that are loaded with dielectric, fed by magnetrons, and operate in a superconducting helical solenoid magnet. The first phase of this project saw the development of a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb3Sn based HS test section. Two very novel ideas are required to realize the design. The first idea is the use of dielectric inserts in the RF cavities to make them smaller for a given frequency so that the cavities and associated plumbing easily fit inside the magnet cryostat. Calculations indicate that heat loads will be tolerable, while RF breakdown of the dielectric inserts will be suppressed by the pressurized hydrogen gas. The second new idea is the use of a multi-layer Nb3Sn helical solenoid. The technology demonstrations for the two aforementioned key components of a 10T, 805 MHz HCC were begun in this project. The work load in the Fermilab Technical Division made it difficult to test a multi-layer Nb3Sn solenoid as originally planned. Instead, a complementary project was approved by the DOE

  3. Ultraviolet laser desorption/ionization mass spectrometry of single-core and multi-core polyaromatic hydrocarbons under variable conditions of collisional cooling: insights into the generation of molecular ions, fragments and oligomers.

    PubMed

    Gámez, Francisco; Hortal, Ana R; Martínez-Haya, Bruno; Soltwisch, Jens; Dreisewerd, Klaus

    2014-11-01

    The ultraviolet laser desorption/ionization of polyaromatic hydrocarbons (PAHs) has been investigated under different background pressures of an inert gas (up to 1.2 mbar of N2) in the ion source of a hybrid, orthogonal-extracting time-of-flight mass spectrometer (oTOF-MS). The study includes an ensemble of six model PAHs with isolated single polyaromatic cores and four ones with multiple cross-linked aromatic and polyaromatic cores. In combination with a weak ion extraction field, the variation of the buffer gas pressure allowed to control the degree of collisional cooling of the desorbed PAHs and, thus, to modulate their decomposition into fragments. The dominant fragmentation channels observed are related to dehydrogenation of the PAHs, in most cases through the cleavage of even numbers of C-H bonds. Breakage of C-C bonds leading to the fragmentation of rings, side chains and core linkages is also observed, in particular, at low buffer gas pressures. The precise patterns of the combined fragmentation processes vary significantly between the PAHs. The highest abundances of molecular PAH ions and cleanest mass spectra were consistently obtained at the highest buffer gas pressure of 1.2 mbar. The effective quenching of the fragmentation pathways at this elevated pressure improves the sensitivity and data interpretation for analytical applications, although the fragmentation of side chains and of bonds between (poly)aromatic cores is not completely suppressed in all cases. Moreover, these results suggest that the detected fragments are generated through thermal equilibrium processes rather than as a result of rapid photolysis. This assumption is further corroborated by a laser desorption/ionization post-source decay analysis using an axial time-of-flight MS. In line with these findings, covalent oligomers of the PAHs, which are presumably formed by association of two or more dehydrogenated fragments, are detected with higher abundances at the lower buffer gas

  4. Calcium - ionized

    MedlinePlus

    ... at both ionized calcium and calcium attached to proteins. You may need to have a separate ionized calcium test if you have factors that increase or decrease total calcium levels. These may include abnormal blood levels ...

  5. ION-BY-ION COOLING EFFICIENCIES

    SciTech Connect

    Gnat, Orly; Ferland, Gary J.

    2012-03-01

    We present ion-by-ion cooling efficiencies for low-density gas. We use Cloudy (version 10.00) to estimate the cooling efficiencies for each ion of the first 30 elements (H-Zn) individually. We present results for gas temperatures between 10{sup 4} and 10{sup 8} K, assuming low densities and optically thin conditions. When nonequilibrium ionization plays a significant role the ionization states deviate from those that obtain in collisional ionization equilibrium (CIE), and the local cooling efficiency at any given temperature depends on specific nonequilibrium ion fractions. The results presented here allow for an efficient estimate of the total cooling efficiency for any ionic composition. We also list the elemental cooling efficiencies assuming CIE conditions. These can be used to construct CIE cooling efficiencies for non-solar abundance ratios or to estimate the cooling due to elements not included in any nonequilibrium computation. All the computational results are listed in convenient online tables.

  6. Cooling of dense stars

    NASA Technical Reports Server (NTRS)

    Tsuruta, S.

    1972-01-01

    Cooling rates were calculated for neutron stars of about one solar mass and 10 km radius, with magnetic fields from zero to about 10 to the 14th power gauss, for extreme cases of maximum and zero superfluidity. The results show that most pulsars are so cold that thermal ionization of surface atoms would be negligible. Nucleon superfluidity and crystallization of heavy nuclei were treated quantitatively, and more realistic hadron star models were chosen. Cooling rates were calculated for a stable hyperon star near the maximum mass limit, a medium weight neutron star, and a light neutron star with neutron-rich heavy nuclei near the minimum mass limit. Results show that cooling rates are a sensitive function of density. The Crab and Vela pulsars are considered, as well as cooling of a massive white dwarf star.

  7. Ionizing radiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter gives a comprehensive review on ionizing irradiation of fresh fruits and vegetables. Topics include principles of ionizing radiation, its effects on pathogenic and spoilage microorganisms, shelf-life, sensory quality, nutritional and phytochemical composition, as well as physiologic and...

  8. Stochastic Cooling

    SciTech Connect

    Blaskiewicz, M.

    2011-01-01

    Stochastic Cooling was invented by Simon van der Meer and was demonstrated at the CERN ISR and ICE (Initial Cooling Experiment). Operational systems were developed at Fermilab and CERN. A complete theory of cooling of unbunched beams was developed, and was applied at CERN and Fermilab. Several new and existing rings employ coasting beam cooling. Bunched beam cooling was demonstrated in ICE and has been observed in several rings designed for coasting beam cooling. High energy bunched beams have proven more difficult. Signal suppression was achieved in the Tevatron, though operational cooling was not pursued at Fermilab. Longitudinal cooling was achieved in the RHIC collider. More recently a vertical cooling system in RHIC cooled both transverse dimensions via betatron coupling.

  9. Status of the MANX muon cooling experiment

    SciTech Connect

    Yonehara, K.; Broemmelsiek, D.; Hu, M.; Jansson, A.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.; Lopes, M.; Shiltsev, V.; Yarba, V.; Yu, M.; /Fermilab /Muons Inc., Batavia

    2008-06-01

    A demonstration experiment of six-dimensional (6D) phase space muon beam cooling is a key milestone on the roadmap toward to a real muon collider. In order to achieve this goal, they have designed the Muon Collider and Neutrino Factory Experiment (MANX) channel, which consists of the Helical Cooling Channel (HCC). They discuss the status of the simulation study of the MANX in this document.

  10. Ionization chamber

    DOEpatents

    Walenta, Albert H.

    1981-01-01

    An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

  11. Ionization chamber

    DOEpatents

    Walenta, A.H.

    An ionization chamber is described which has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionizes the gas.

  12. CF6-6D engine short-term performance deterioration

    NASA Technical Reports Server (NTRS)

    Kramer, W. H.; Paas, J. E.; Smith, J. J.; Wulf, R. H.

    1980-01-01

    Studies conducted as part of the NASA-Lewis CF6 jet engine diagnostics program are summarized. An 82-engine sample of DC-10-10 aircraft engine checkout data that were gathered to define the extent and magnitude of CF6-6D short term performance deterioration were analyzed. These data are substantiated by the performance testing and analytical teardown of CF6-6D short term deterioration engine serial number (ESN) 451507.

  13. The DEP-6D, a new preference-based measure to assess health states of dependency.

    PubMed

    Rodríguez-Míguez, E; Abellán-Perpiñán, J M; Alvarez, X C; González, X M; Sampayo, A R

    2016-03-01

    In medical literature there are numerous multidimensional scales to measure health states for dependence in activities of daily living. However, these scales are not preference-based and are not able to yield QALYs. On the contrary, the generic preference-based measures are not sensitive enough to measure changes in dependence states. The objective of this paper is to propose a new dependency health state classification system, called DEP-6D, and to estimate its value set in such a way that it can be used in QALY calculations. DEP-6D states are described as a combination of 6 attributes (eat, incontinence, personal care, mobility, housework and cognition problems), with 3-4 levels each. A sample of 312 Spanish citizens was surveyed in 2011 to estimate the DEP-6D preference-scoring algorithm. Each respondent valued six out of the 24 states using time trade-off questions. After excluding those respondents who made two or more inconsistencies (6% out of the sample), each state was valued between 66 and 77 times. The responses present a high internal and external consistency. A random effect model accounting for main effects was the preferred model to estimate the scoring algorithm. The DEP-6D describes, in general, more severe problems than those usually described by means of generic preference-based measures. The minimum score predicted by the DEP-6D algorithm is -0.84, which is considerably lower than the minimum value predicted by the EQ-5D and SF-6D algorithms. The DEP-6D value set is based on community preferences. Therefore it is consistent with the so-called 'societal perspective'. Moreover, DEP-6D preference weights can be used in QALY calculations and cost-utility analysis. PMID:26921836

  14. IONIZATION CHAMBER

    DOEpatents

    Redman, W.C.; Shonka, F.R.

    1958-02-18

    This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

  15. The SF-6D health utility index in carpal tunnel syndrome.

    PubMed

    Atroshi, I; Gummesson, C; McCabe, S J; Ornstein, E

    2007-04-01

    Cost effectiveness is an important factor to consider when choosing between various hand surgical interventions. Health utility measures can be used to determine cost effectiveness. The SF-6D is a health utility index derived from 11 items of the SF-36 quality of life questionnaire; values range from 0.296 to 1.0 ("perfect" health). We evaluated the validity of the SF-6D in patients with carpal tunnel syndrome (CTS) who completed the SF-36 and the CTS symptom severity and functional status questionnaire before and 3 months after carpal tunnel release. Complete responses to the SF-6D items were available for 100 patients at baseline and 95 patients at baseline and follow-up. The mean SF-6D health utility index was 0.69 (SD 0.13) before surgery and 0.77 (SD 0.13) after surgery (moderate effect size). The SF-6D could discriminate between patient groups differing in self-rated global health and in whether, or not, they had a minimal clinically important improvement in CTS symptom severity after surgery. The SF-6D appears to be a valid measure of health utilities in patients with CTS and can be used in cost effectiveness studies. PMID:17223234

  16. SEMA6D Expression and Patient Survival in Breast Invasive Carcinoma

    PubMed Central

    Chen, Dongquan; Li, Yufeng; Wang, Lizhong; Jiao, Kai

    2015-01-01

    Breast cancer (BC) is the second most common cancer diagnosed in American women and is also the second leading cause of cancer death in women. Research has focused heavily on BC metastasis. Multiple signaling pathways have been implicated in regulating BC metastasis. Our knowledge of regulation of BC metastasis is, however, far from complete. Identification of new factors during metastasis is an essential step towards future therapy. Our labs have focused on Semaphorin 6D (SEMA6D), which was implicated in immune responses, heart development, and neurogenesis. It will be interesting to know SEMA6D-related genomic expression profile and its implications in clinical outcome. In this study, we examined the public datasets of breast invasive carcinoma from The Cancer Genome Atlas (TCGA). We analyzed the expression of SEMA6D along with its related genes, their functions, pathways, and potential as copredictors for BC patients' survival. We found 6-gene expression profile that can be used as such predictors. Our study provides evidences for the first time that breast invasive carcinoma may contain a subtype based on SEMA6D expression. The expression of SEMA6D gene may play an important role in promoting patient survival, especially among triple negative breast cancer patients. PMID:25973277

  17. Rectlinear cooling scheme for bright muon sources

    SciTech Connect

    Stratakis, Diktys

    2015-05-03

    A fast cooling technique is described that simultaneously reduces all six phase-space dimensions of a charged particle beam. In this process, cooling is accomplished by reducing the beam momentum through ionization energy loss in absorbers and replenishing the momentum loss only in the longitudinal direction rf cavities. In this work we review its main features and describe the main results.

  18. Cooling wall

    SciTech Connect

    Nosenko, V.I.

    1995-07-01

    Protecting the shells of blast furnaces is being resolved by installing cast iron cooling plates. The cooling plates become non-operational in three to five years. The problem is that defects occur in manufacturing the cooling plates. With increased volume and intensity of work placed on blast furnaces, heat on the cast iron cooling plates reduces their reliability that limits the interim repair period of blast furnaces. Scientists and engineers from the Ukraine studied this problem for several years, developing a new method of cooling the blast furnace shaft called the cooling wall. Traditional cast iron plates were replaced by a screen of steel tubes, with the area between the tubes filled with fireproof concrete. Before placing the newly developed furnace shaft into operation, considerable work was completed such as theoretical calculations, design, research of temperature fields and tension. Continual testing over many years confirms the value of this research in operating blast furnaces. The cooling wall works with water cooling as well as vapor cooling and is operating in 14 blast furnaces in the Ukraine and two in Russia, and has operated for as long as 14 years.

  19. First-principles calculation of the structural stability of 6d transition metals

    SciTech Connect

    Oestlin, A.; Vitos, L.

    2011-09-15

    The phase stability of the 6d transition metals (elements 103-111) is investigated using first-principles electronic-structure calculations. Comparison with the lighter transition metals reveals that the structural sequence trend is broken at the end of the 6d series. To account for this anomalous behavior, the effect of relativity on the lattice stability is scrutinized, taking different approximations into consideration. It is found that the mass-velocity and Darwin terms give important contributions to the electronic structure, leading to changes in the interstitial charge density and, thus, in the structural energy difference.

  20. Cool Shelter

    ERIC Educational Resources Information Center

    Praeger, Charles E.

    2005-01-01

    Amid climbing energy costs and tightening budgets, administrators at school districts, colleges and universities are looking for all avenues of potential savings while promoting sustainable communities. Cool metal roofing can save schools money and promote sustainable design at the same time. Cool metal roofing keeps the sun's heat from collecting…

  1. Fundamental studies of molecular multiphoton ionization

    SciTech Connect

    Miller, J.C.; Compton, R.N.

    1984-04-01

    For several years the authors have performed fundamental studies of molecular multiphoton ionization (MPI). We will present a potpourri of techniques and results chosen to illustrate the interesting complexities of molecular MPI. Techniques used include time-of-flight mass spectroscopy, photoelectron spectroscopy, supersonic expansion cooling of molecular beams, harmonic generation, two-color laser MPI, and polarization spectroscopy. Whenever possible the relevance of these results to resonance ionization spectroscopy schemes will be delineated. 23 references, 10 figures.

  2. 29 CFR 1905.11 - Variances and other relief under section 6(d).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Variances and other relief under section 6(d). 1905.11... ADMINISTRATION, DEPARTMENT OF LABOR RULES OF PRACTICE FOR VARIANCES, LIMITATIONS, VARIATIONS, TOLERANCES, AND EXEMPTIONS UNDER THE WILLIAMS-STEIGER OCCUPATIONAL SAFETY AND HEALTH ACT OF 1970 Applications for...

  3. Cooled railplug

    DOEpatents

    Weldon, William F.

    1996-01-01

    The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers.

  4. Cool School.

    ERIC Educational Resources Information Center

    Stephens, Suzanne

    1980-01-01

    The design for Floyd Elementary School in Miami (Florida) seeks to harness solar energy to provide at least 70 percent of the annual energy for cooling needs and 90 percent for hot water. (Author/MLF)

  5. Multiphoton ionization of ions, neutrals, and clusters. Progress report

    SciTech Connect

    Wessel, J.

    1991-06-28

    Scientific results are summarized from a three year research program on multiphoton ionization in aromatic molecules, clusters, and their ions. As originally proposed, the studies elucidated a new cluster ionization mechanism, characterized properties of long range intermolecular interactions, and investigated electronic transitions of aromatic cations cooled in a supersonic beam. The studies indicate that the new cluster ionization mechanism is highly efficient and dominates conventional 1 + 1 resonant ionization. In the case of the dimer of the large aromatic molecule fluorene, the results suggest that excimer formation competes with a direct ionization process. Highly selective excitonic spectra have been identified for several cluster species.

  6. Superconducting magnet system for muon beam cooling

    SciTech Connect

    Andreev, N.; Johnson, R.P.; Kashikhin, V.S.; Kashikhin, V.V.; Novitski, I.; Yonehara, K.; Zlobin, A.; /Fermilab

    2006-08-01

    A helical cooling channel has been proposed to quickly reduce the six-dimensional phase space of muon beams for muon colliders, neutrino factories, and intense muon sources. A novel superconducting magnet system for a muon beam cooling experiment is being designed at Fermilab. The inner volume of the cooling channel is filled with liquid helium where passing muon beam can be decelerated and cooled in a process of ionization energy loss. The magnet parameters are optimized to match the momentum of the beam as it slows down. The results of 3D magnetic analysis for two designs of magnet system, mechanical and quench protection considerations are discussed.

  7. Comparison of SF-6D and EQ-5D Scores in Patients With Breast Cancer

    PubMed Central

    Yousefi, Mahmood; Najafi, Safa; Ghaffari, Shahram; Mahboub-Ahari, Alireza; Ghaderi, Hossein

    2016-01-01

    Background Utility values are a key component of a cost-utility analysis. The EQ-5D and SF-6D are two commonly used measures for deriving utilities. Of particular importance is assessing the performance of these instruments in terms of validity. Objectives This study aimed to compare the performance of the EQ-5D and the SF-6D in different states of breast cancer. Patients and Methods This was a cross-sectional study of 163 patients with breast cancer who attended the breast cancer subspecialty clinic affiliated with the breast cancer research center (BCRC) at ACECR, in Tehran, Iran, and were consecutively recruited. Patients completed several questionnaires, including the EQ-5D, SF-36, and general questions regarding their demographic characteristics. Utility values for different states of breast cancer were obtained using predetermined algorithms for the EQ-5D and SF-6D. The distribution of the utility values and the differences between the different states for both instruments were statistically assessed. Furthermore, the agreement between the two instruments was evaluated using intra-class correlation coefficients and Bland-Altman plots. Results The mean and median EQ-5D utility scores for the total sample were 0.685 and 0.761, respectively. The mean SF-6D utility score for the total sample was 0.653, and the median utility score was 0.640. The mean utility values of the EQ-5D for “state P,” “state R,” “state S,” and “state M” were estimated as 0.674, 0.718, 0.730, and 0.552, respectively. The SF-6D provided mean utility values of 0.638, 0.677, 0.681, and 0.587 for those states. Both instruments assigned statistically significant (P < 0.01) scores for different states. The intra-class correlation for the two measures was 0.677 (95% confidence interval (CI): 0.558 - 0.764). The Bland-Altman plot indicated a better agreement on the higher values and that at higher values, the EQ-5D yields a higher score than the SF-6D; this relationship was

  8. Mergers, cooling flows, and evaporation

    NASA Technical Reports Server (NTRS)

    Sparks, W. B.

    1993-01-01

    Mergers (the capture of cold gas, especially) can have a profound influence on the hot coronal gas of early-type galaxies and clusters, potentially inducing symptoms hitherto attributed to a cooling flow, if thermal conduction is operative in the coronal plasma. Heat can be conducted from the hot phase into the cold phase, simultaneously ionizing the cold gas to make optical filaments, while locally cooling the coronal gas to mimic a cooling-flow. If there is heat conduction, though, there is no standard cooling-flow since radiative losses are balanced by conduction and not mass deposition. Amongst the strongest observational support for the existence of cooling-flows is the presence of intermediate temperature gas with x-ray emission-line strengths in agreement with cooling-flow models. Here, x-ray line strengths are calculated for this alternative model, in which mergers are responsible for the observed optical and x-ray properties. Since gas around 10(exp 4) K is thermally stable, the cold cloud need not necessarily evaporate and hydrostatic solutions exist. Good agreement with the x-ray data is obtained. The relative strengths of intermediate temperature x-ray emission lines are in significantly better agreement with a simple conduction model than with published cooling-flow models. The good agreement of the conduction model with optical, infrared and x-ray data indicates that significantly more theoretical effort into this type of solution would be profitable.

  9. Geometric engineering, mirror symmetry and 6{d}_{(1,0)}to 4{d}_{(N=2)}

    NASA Astrophysics Data System (ADS)

    Del Zotto, Michele; Vafa, Cumrun; Xie, Dan

    2015-11-01

    We study compactification of 6 dimensional (1,0) theories on T 2. We use geometric engineering of these theories via F-theory and employ mirror symmetry technology to solve for the effective 4d N=2 geometry for a large number of the (1 ,0) theories including those associated with conformal matter. Using this we show that for a given 6d theory we can obtain many inequivalent 4d N=2 SCFTs. Some of these respect the global symmetries of the 6d theory while others exhibit SL(2 , ℤ) duality symmetry inherited from global diffeomorphisms of the T 2. This construction also explains the 6d origin of moduli space of 4d affine ADE quiver theories as flat ADE connections on T 2. Among the resulting 4 d N=2 CFTs we find theories whose vacuum geometry is captured by an LG theory (as opposed to a curve or a local CY geometry). We obtain arbitrary genus curves of class S with punctures from toroidal compactification of (1 , 0) SCFTs where the curve of the class S theory emerges through mirror symmetry. We also show that toroidal compactification of the little string version of these theories can lead to class S theories with no punctures on arbitrary genus Riemann surface.

  10. SU-E-J-34: Setup Accuracy in Spine SBRT Using CBCT 6D Image Guidance in Comparison with 6D ExacTrac

    SciTech Connect

    Han, Z; Yip, S; Lewis, J; Mannarino, E; Friesen, S; Wagar, M; Hacker, F

    2015-06-15

    Purpose Volumetric information of the spine captured on CBCT can potentially improve the accuracy in spine SBRT setup that has been commonly performed through 2D radiographs. This work evaluates the setup accuracy in spine SBRT using 6D CBCT image guidance that recently became available on Varian systems. Methods ExacTrac radiographs have been commonly used for Spine SBRT setup. The setup process involves first positioning patients with lasers followed by localization imaging, registration, and repositioning. Verification images are then taken providing the residual errors (ExacTracRE) before beam on. CBCT verification is also acquired in our institute. The availability of both ExacTrac and CBCT verifications allows a comparison study. 41 verification CBCT of 16 patients were retrospectively registered with the planning CT enabling 6D corrections, giving CBCT residual errors (CBCTRE) which were compared with ExacTracRE. Results The RMS discrepancies between CBCTRE and ExacTracRE are 1.70mm, 1.66mm, 1.56mm in vertical, longitudinal and lateral directions and 0.27°, 0.49°, 0.35° in yaw, roll and pitch respectively. The corresponding mean discrepancies (and standard deviation) are 0.62mm (1.60mm), 0.00mm (1.68mm), −0.80mm (1.36mm) and 0.05° (0.58°), 0.11° (0.48°), −0.16° (0.32°). Of the 41 CBCT, 17 had high-Z surgical implants. No significant difference in ExacTrac-to-CBCT discrepancy was observed between patients with and without the implants. Conclusion Multiple factors can contribute to the discrepancies between CBCT and ExacTrac: 1) the imaging iso-centers of the two systems, while calibrated to coincide, can be different; 2) the ROI used for registration can be different especially if ribs were included in ExacTrac images; 3) small patient motion can occur between the two verification image acquisitions; 4) the algorithms can be different between CBCT (volumetric) and ExacTrac (radiographic) registrations.

  11. Cooled railplug

    DOEpatents

    Weldon, W.F.

    1996-05-07

    The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers. 10 figs.

  12. Cooling Vest

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Because quadriplegics are unable to perspire below the level of spinal injury, they cannot tolerate heat stress. A cooling vest developed by Ames Research Center and Upjohn Company allows them to participate in outdoor activities. The vest is an adaptation of Ames technology for thermal control garments used to remove excess body heat of astronauts. The vest consists of a series of corrugated channels through which cooled water circulates. Its two outer layers are urethane coated nylon, and there is an inner layer which incorporates the corrugated channels. It can be worn as a backpack or affixed to a wheelchair. The unit includes a rechargeable battery, mini-pump, two quart reservoir and heat sink to cool the water.

  13. Prospects of laser cooling in atomic thallium

    SciTech Connect

    Fan, Isaac; Chen, Tzu-Ling; Liu, Yu-Sheng; Lien, Yu-Hung; Liu, Yi-Wei; Shy, Jow-Tsong

    2011-10-15

    One of the most precisely determined upper limits for the electron electric dipole moment (EDM) is set by the thallium (Tl) atomic beam experiment. One way to enhance the sensitivity of the atomic beam setup is to laser cool the Tl atoms to reduce the EDM-like phase caused by the Exv effect. In this report, a cooling scheme based on the 6P{sub 3/2}(F=2){r_reversible}6D{sub 5/2}(F{sup '}=3) transition in Tl is proposed. The absolute frequency measurement of this nearly closed-cycle transition was performed in an atomic beam apparatus. Two Ti:sapphire lasers were frequency-doubled using enhancement cavities in X-type configurations to provide the needed 377- and 352-nm light sources for the optical pumping and cooling transitions, respectively. The absolute frequency of this cooling transition is determined to be 851 634 646(56) MHz.

  14. Weakly ionized cosmic gas: Ionization and characterization

    NASA Technical Reports Server (NTRS)

    Rosenberg, M.; Mendis, D. A.; Chow, V. W.

    1994-01-01

    Since collective plasma behavior may determine important transport processes (e.g., plasma diffusion across a magnetic field) in certain cosmic environments, it is important to delineate the parameter space in which weakly ionized cosmic gases may be characterized as plasmas. In this short note, we do so. First, we use values for the ionization fraction given in the literature, wherein the ionization is generally assumed to be due primarily to ionization by cosmic rays. We also discuss an additional mechanism for ionization in such environments, namely, the photoelectric emission of electrons from cosmic dust grains in an interstellar Far Ultra Violet (FUV) radiation field. Simple estimates suggest that under certain conditions this mechanism may dominate cosmic ray ionization, and possibly also the photoionization of metal atoms by the interstellar FUV field, and thereby lead to an enhanced ionization level.

  15. Stochastic cooling

    SciTech Connect

    Bisognano, J.; Leemann, C.

    1982-03-01

    Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron.

  16. 40 CFR 35.1605-9 - Indian Tribe set forth at 40 CFR 130.6(d).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Publicly Owned Freshwater Lakes § 35.1605-9 Indian Tribe set forth at 40 CFR 130.6(d). A Tribe meeting the requirements set forth at 40 CFR 130.6(d). ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Indian Tribe set forth at 40 CFR...

  17. 40 CFR 35.1605-9 - Indian Tribe set forth at 40 CFR 130.6(d).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Publicly Owned Freshwater Lakes § 35.1605-9 Indian Tribe set forth at 40 CFR 130.6(d). A Tribe meeting the requirements set forth at 40 CFR 130.6(d). ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Indian Tribe set forth at 40 CFR...

  18. 40 CFR 35.1605-9 - Indian Tribe set forth at 40 CFR 130.6(d).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Publicly Owned Freshwater Lakes § 35.1605-9 Indian Tribe set forth at 40 CFR 130.6(d). A Tribe meeting the requirements set forth at 40 CFR 130.6(d). ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Indian Tribe set forth at 40 CFR...

  19. 40 CFR 35.1605-9 - Indian Tribe set forth at 40 CFR 130.6(d).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Publicly Owned Freshwater Lakes § 35.1605-9 Indian Tribe set forth at 40 CFR 130.6(d). A Tribe meeting the requirements set forth at 40 CFR 130.6(d). ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Indian Tribe set forth at 40 CFR...

  20. 40 CFR 35.1605-9 - Indian Tribe set forth at 40 CFR 130.6(d).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Publicly Owned Freshwater Lakes § 35.1605-9 Indian Tribe set forth at 40 CFR 130.6(d). A Tribe meeting the requirements set forth at 40 CFR 130.6(d). ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Indian Tribe set forth at 40 CFR...

  1. Dynamics of reactions O((1)D)+C(6)H(6) and C(6)D(6).

    PubMed

    Chen, Hui-Fen; Liang, Chi-Wei; Lin, Jim J; Lee, Yuan-Pern; Ogilvie, J F; Xu, Z F; Lin, M C

    2008-11-01

    The reaction between O((1)D) and C(6)H(6) (or C(6)D(6)) was investigated with crossed-molecular-beam reactive scattering and time-resolved Fourier-transform infrared spectroscopy. From the crossed-molecular-beam experiments, four product channels were identified. The major channel is the formation of three fragments CO+C(5)H(5)+H; the channels for formation of C(5)H(6)+CO and C(6)H(5)O+H from O((1)D)+C(6)H(6) and OD+C(6)D(5) from O((1)D)+C(6)D(6) are minor. The angular distributions for the formation of CO and H indicate a mechanism involving a long-lived collision complex. Rotationally resolved infrared emission spectra of CO (12.9 for O((1)D)+C(6)D(6) is consistent with the expectation for an abstraction reaction. The mechanism of the reaction may be understood from considering the energetics of the intermediate species and transition states calculated at the G2M(CC5) level of theory for the O((1)D)+C(6)H(6) reaction. The experimentally observed branching ratios and deuterium isotope effect are consistent with those predicted from calculations. PMID:19045343

  2. Two-photon ionization thresholds of matrix-assisted laser desorption/ionization matrix clusters.

    PubMed

    Lin, Q; Knochenmuss, R

    2001-01-01

    Direct two-photon ionization of the matrix has been considered a likely primary ionization mechanism in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. This mechanism requires that the vertical ionization threshold of matrix materials be below twice the laser photon energy. Because dimers and larger aggregates may be numerous in the early stages of the MALDI plume expansion, their ionization thresholds are important as well. We have used two-color two-photon ionization to determine the ionization thresholds of jet cooled clusters of an important matrix, 2,5-dihydroxy benzoic acid (DHB), and mixed clusters with the thermal decomposition product of DHB, hydroquinone. The thresholds of the clusters were reduced by only a few tenths of an eV compared to the monomers, to an apparent limit of 7.82 eV for pure DHB clusters. None of the investigated clusters can be directly ionized by two nitrogen laser photons (7.36 eV), and the ionization efficiency at the thresholds is low. PMID:11507754

  3. Theoretical studies of the long lifetimes of the 6 d D 3 /2 ,5 /2 2 states in Fr: Implications for parity-nonconservation measurements

    NASA Astrophysics Data System (ADS)

    Sahoo, B. K.; Das, B. P.

    2015-11-01

    Lifetimes of the 6 d D 3 /2 2 and 6 d D 5 /2 2 states in Fr are determined from calculations of the radiative transition amplitudes of the allowed electric dipole (E 1 ) and the forbidden electric quadrupole (E 2 ) and magnetic dipole (M 1 ) channels which were performed using the second-order many-body perturbation theory and the coupled-cluster method at different levels of approximations in the relativistic framework. The values obtained for these two quantities are 540(10) and 1704(32) ns, respectively. These relatively long lifetimes and the large electric dipole parity-non-conserving amplitudes of 7 s S 1 /2 2 6 d D 3 /2 ,5 /2 2 transitions strongly favor Fr as a leading candidate for the measurement of parity nonconservation arising from the neutral-current weak interaction and the nuclear anapole moment. In another important application, these 6 D states in Fr can be used efficiently for resonance ionization spectroscopic techniques to carry out precise measurements of the properties of the higher excited states due to the long lifetimes of these states.

  4. Cool Sportswear

    NASA Technical Reports Server (NTRS)

    1982-01-01

    New athletic wear design based on the circulating liquid cooling system used in the astronaut's space suits, allows athletes to perform more strenuous activity without becoming overheated. Techni-Clothes gear incorporates packets containing a heat-absorbing gel that slips into an insulated pocket of the athletic garment and is positioned near parts of the body where heat transfer is most efficient. A gel packet is good for about one hour. Easily replaced from a supply of spares in an insulated container worn on the belt. The products, targeted primarily for runners and joggers and any other athlete whose performance may be affected by hot weather, include cooling headbands, wrist bands and running shorts with gel-pack pockets.

  5. (16)Oxygen irradiation enhances cued fear memory in B6D2F1 mice.

    PubMed

    Raber, Jacob; Marzulla, Tessa; Kronenberg, Amy; Turker, Mitchell S

    2015-11-01

    The space radiation environment includes energetic charged particles that may impact cognitive performance. We assessed the effects of (16)O ion irradiation on cognitive performance of C57BL/6J × DBA/2J F1 (B6D2F1) mice at OHSU (Portland, OR) one month following irradiation at Brookhaven National Laboratory (BNL, Upton, NY). Hippocampus-dependent contextual fear memory and hippocampus-independent cued fear memory of B6D2F1 mice were tested. (16)O ion exposure enhanced cued fear memory. This effect showed a bell-shaped dose response curve. Cued fear memory was significantly stronger in mice irradiated with (16)O ions at a dose of 0.4 or 0.8 Gy than in sham-irradiated mice or following irradiation at 1.6 Gy. In contrast to cued fear memory, contextual fear memory was not affected following (16)O ion irradiation at the doses used in this study. These data indicate that the amygdala might be particularly susceptible to effects of (16)O ion exposure. PMID:26553639

  6. 16Oxygen irradiation enhances cued fear memory in B6D2F1 mice

    NASA Astrophysics Data System (ADS)

    Raber, Jacob; Marzulla, Tessa; Kronenberg, Amy; Turker, Mitchell S.

    2015-11-01

    The space radiation environment includes energetic charged particles that may impact cognitive performance. We assessed the effects of 16O ion irradiation on cognitive performance of C57BL/6J × DBA/2J F1 (B6D2F1) mice at OHSU (Portland, OR) one month following irradiation at Brookhaven National Laboratory (BNL, Upton, NY). Hippocampus-dependent contextual fear memory and hippocampus-independent cued fear memory of B6D2F1 mice were tested. 16O ion exposure enhanced cued fear memory. This effect showed a bell-shaped dose response curve. Cued fear memory was significantly stronger in mice irradiated with 16O ions at a dose of 0.4 or 0.8 Gy than in sham-irradiated mice or following irradiation at 1.6 Gy. In contrast to cued fear memory, contextual fear memory was not affected following 16O ion irradiation at the doses used in this study. These data indicate that the amygdala might be particularly susceptible to effects of 16O ion exposure.

  7. SUSY breaking and moduli stabilization from fluxes in gauged 6D supergravity

    NASA Astrophysics Data System (ADS)

    Aghababaie, Yashar; Burgess, Clifford P.; Parameswaran, Susha L.; Quevedo, Fernando

    2003-03-01

    We construct the 4D N=1 supergravity which describes the low-energy limit of 6D supergravity compactified on a sphere with a monopole background a la Salam and Sezgin. This provides a simple setting sharing the main properties of realistic string compactifications such as flat 4D spacetime, chiral fermions and N=1 supersymmetry as well as Fayet-Iliopoulos terms induced by the Green-Schwarz mechanism. The matter content of the resulting theory is a supersymmetric SO(3) × U(1) gauge model with two chiral multiplets, S and T. The expectation value of T is fixed by the classical potential, and S describes a flat direction to all orders in perturbation theory. We consider possible perturbative corrections to the Kahler potential in inverse powers of ReS and ReT, and find that under certain circumstances, and when taken together with low-energy gaugino condensation, these can lift the degeneracy of the flat direction for ReS. The resulting vacuum breaks supersymmetry at moderately low energies in comparison with the compactification scale, with positive cosmological constant. It is argued that the 6D model might itself be obtained from string compactifications, giving rise to realistic string compactifications on non Ricci flat manifolds. Possible phenomenological and cosmological applications are briefly discussed.

  8. Helical channel design and technology for cooling of muon beams

    SciTech Connect

    Yonehara, K; Derbenev, Y.S.; Johnson, R.P.; /MUONS Inc., Batavia

    2010-08-01

    Novel magnetic helical channel designs for capture and cooling of bright muon beams are being developed using numerical simulations based on new inventions such as helical solenoid (HS) magnets and hydrogen-pressurized RF (HPRF) cavities. We are close to the factor of a million six-dimensional phase space (6D) reduction needed for muon colliders. Recent experimental and simulation results are presented.

  9. Helical Channel Design and Technology for Cooling of Muon Beams

    NASA Astrophysics Data System (ADS)

    Yonehara, K.; Derbenev, Y. S.; Johnson, R. P.

    2010-11-01

    Novel magnetic helical channel designs for capture and cooling of bright muon beams are being developed using numerical simulations based on new inventions such as helical solenoid (HS) magnets and hydrogen-pressurized RF (HPRF) cavities. We are close to the factor of a million six-dimensional phase space (6D) reduction needed for muon colliders. Recent experimental and simulation results are presented.

  10. Helical Channel Design and Technology for Cooling of Muon Beams

    SciTech Connect

    Yonehara, K.; Derbenev, Y. S.; Johnson, R. P.

    2010-11-04

    Novel magnetic helical channel designs for capture and cooling of bright muon beams are being developed using numerical simulations based on new inventions such as helical solenoid (HS) magnets and hydrogen-pressurized RF (HPRF) cavities. We are close to the factor of a million six-dimensional phase space (6D) reduction needed for muon colliders. Recent experimental and simulation results are presented.

  11. Predicting SF-6D utility scores from the Neck Disability Index and Numeric Rating Scales for Neck and Arm Pain

    PubMed Central

    Carreon, Leah Y.; Anderson, Paul A.; McDonough, Christine M.; Djurasovic, Mladen; Glassman, Steven D.

    2010-01-01

    Study Design Cross-sectional cohort Objective This study aims to provide an algorithm estimate SF-6D utilities using data from the NDI, neck pain and arm pain scores. Summary of Background Data Although cost-utility analysis is increasingly used to provide information about the relative value of alternative interventions, health state values or utilities are rarely available from clinical trial data. The Neck Disability Index (NDI) and numeric rating scales for neck and arm pain, are widely used disease-specific measures of symptoms, function and disability in patients with cervical degenerative disorders. The purpose of this study is to provide an algorithm to allow estimation of SF-6D utilities using data from the NDI, and numeric rating scales for neck and arm pain. Methods SF-36, NDI, neck and arm pain rating scale scores were prospectively collected pre-operatively, at 12 and 24 months post-operatively in 2080 patients undergoing cervical fusion for degenerative disorders. SF-6D utilities were computed and Spearman correlation coefficients were calculated for paired observations from multiple time points between NDI, neck and arm pain scores and SF-6D utility scores. SF-6D scores were estimated from the NDI, neck and arm pain scores using a linear regression model. Using a separate, independent dataset of 396 patients in which and NDI scores were available SF-6D was estimated for each subject and compared to their actual SF-6D. Results The mean age for those in the development sample, was 50.4 ± 11.0 years and 33% were male. In the validation sample the mean age was 53.1 ± 9.9 years and 35% were male. Correlations between the SF-6D and the NDI, neck and arm pain scores were statistically significant (p<0.0001) with correlation coefficients of 0.82, 0.62, and 0.50 respectively. The regression equation using NDI alone to predict SF-6D had an R2 of 0.66 and a root mean square error (RMSE) of 0.056. In the validation analysis, there was no statistically

  12. REACTOR COOLING

    DOEpatents

    Quackenbush, C.F.

    1959-09-29

    A nuclear reactor with provisions for selectively cooling the fuel elements is described. The reactor has a plurality of tubes extending throughout. Cylindrical fuel elements are disposed within the tubes and the coolant flows through the tubes and around the fuel elements. The fuel elements within the central portion of the reactor are provided with roughened surfaces of material. The fuel elements in the end portions of the tubes within the reactor are provlded with low conduction jackets and the fuel elements in the region between the central portion and the end portions are provided with smooth surfaces of high heat conduction material.

  13. Comparison of Temperature Programmable Split/Splitless and Cool On-Column Inlets for the Determination of Glycerol and Glycerides in Biodiesel by Gas Chromatography with Flame Ionization Detection.

    PubMed

    Giardina, Matthew; McCurry, James D

    2016-01-01

    The European Standard EN 14105:2011-07 is an analysis method for quantifying free glycerol and residual mono-, di- and triacylglycerides impurities in biodiesel by gas chromatography. The method specifies an "on-column injector or equivalent device" as the means of sample introduction. Cool on-column (COC) would appear to be an ideal choice, particularly for quantifying triacylglycerides, as it provides high quantitative accuracy and precision with minimal mass discrimination. However, there are a few drawbacks in using COC for this application. The relatively high concentration of the biodiesel in the prepared samples impedes solvent focusing of early eluting compounds such as glycerol, causing band broadening and shifts in retention time compared with the external calibration standards. More problematic is method robustness when using a metal retention gap. Repeated injections onto the retention gap cause the method control specification to fail within relatively few injections. As an alternative, a temperature programmable split/splitless (TPSS) inlet was investigated for performance equivalency. The results demonstrate that the TPSS yields concentration measurements indistinguishable from the COC inlet at the 95% confidence level. In addition, the robustness of the TPSS far exceeds that of the COC inlet by eliminating the performance control failure and providing solvent focusing for the early eluting peaks. PMID:26921893

  14. Ion energies in high power impulse magnetron sputtering with and without localized ionization zones

    SciTech Connect

    Yang, Yuchen; Tanaka, Koichi; Liu, Jason; Anders, André

    2015-03-23

    High speed imaging of high power impulse magnetron sputtering discharges has revealed that ionization is localized in moving ionization zones but localization disappears at high currents for high yield targets. This offers an opportunity to study the effect ionization zones have on ion energies. We measure that ions have generally higher energies when ionization zones are present, supporting the concept that these zones are associated with moving potential humps. We propose that the disappearance of ionization zones is caused by an increased supply of atoms from the target which cools electrons and reduces depletion of atoms to be ionized.

  15. Laser Cooled Strontium Source for an Ion Interferometer

    NASA Astrophysics Data System (ADS)

    Lyon, Mary; Archibald, James; Erickson, Christopher; Durfee, Dallin

    2010-10-01

    We present a Strontium-87 magneto-optical trap (MOT) in a Low-Velocity-Intense-Source (LVIS) as the source of cooled, collimated atoms for an ion interferometer. Laser cooling and trapping is accomplished with a 461 nm frequency doubled laser and a pair of permanent magnets. A beam of cooled atoms is produced by passing the atoms through a hole drilled in one of the retroreflecting optics. The atoms are then photo-ionized in a two photon process.

  16. Ionization potentials of seaborgium

    SciTech Connect

    Johnson, E.; Pershina, V.; Fricke, B.

    1999-10-21

    Multiconfiguration relativistic Dirac-Fock values were calculated for the first six ionization potentials of seaborgium and of the other group 6 elements. No experimental ionization potentials are available for seaborgium. Accurate experimental values are not available for all of the other ionization potentials. Ionic radii for the 4+ through 6+ ions of seaborgium are also presented. The ionization potentials and ionic radii obtained will be used to predict some physiochemical properties of seaborgium and its compounds.

  17. Ionization Energies of Lanthanides

    ERIC Educational Resources Information Center

    Lang, Peter F.; Smith, Barry C.

    2010-01-01

    This article describes how data are used to analyze the pattern of ionization energies of the lanthanide elements. Different observed pathways of ionization between different ground states are discussed, and the effects of pairing, exchange, and orbital interactions on ionization energies of the lanthanides are evaluated. When all the above…

  18. Radiative cooling II: effects of density and metallicity

    NASA Astrophysics Data System (ADS)

    Wang, Ye; Ferland, G. J.; Lykins, M. L.; Porter, R. L.; van Hoof, P. A. M.; Williams, R. J. R.

    2014-06-01

    This work follows Lykins et al. discussion of classic plasma cooling function at low density and solar metallicity. Here, we focus on how the cooling function changes over a wide range of density (nH <1012 cm-3) and metallicity (Z < 30 Z⊙). We find that high densities enhance the ionization of elements such as hydrogen and helium until they reach local thermodynamic equilibrium. By charge transfer, the metallicity changes the ionization of hydrogen when it is partially ionized. We describe the total cooling function as a sum of four parts: those due to H&He, the heavy elements, electron-electron bremsstrahlung and grains. For the first three parts, we provide a low-density limit cooling function, a density dependence function, and a metallicity-dependent function. These functions are given with numerical tables and analytical fit functions. We discuss grain cooling only in the interstellar medium case. We then obtain a total cooling function that depends on density, metallicity and temperature. As expected, collisional de-excitation suppresses the heavy elements cooling. Finally, we provide a function giving the electron fraction, which can be used to convert the cooling function into a cooling rate.

  19. SU-F-BRE-05: Development and Evaluation of a Real-Time Robotic 6D Quality Assurance Phantom

    SciTech Connect

    Belcher, AH; Liu, X; Grelewicz, Z; Wiersma, RD

    2014-06-15

    Purpose: A 6 degree-of-freedom robotic phantom capable of reproducing dynamic tumor motion in 6D was designed to more effectively match solid tumor movements throughout pre-treatment scanning and radiation therapy. With the abundance of optical and x-ray 6D real-time tumor tracking methodologies clinically available, and the substantial dosimetric consequences of failing to consider tumor rotation as well as translation, this work presents the development and evaluation of a 6D instrument with the facility to improve quality assurance. Methods: An in-house designed and built 6D robotic motion phantom was constructed following the so-called Stewart-Gough parallel kinematics platform archetype. The device was then controlled using an inverse kinematics formulation, and precise movements in all six degrees of freedom (X, Y, Z, pitch, roll, and yaw) as well as previously obtained cranial motion, were effectively executed. The robotic phantom movements were verified using a 15 fps 6D infrared marker tracking system (Polaris, NDI), and quantitatively compared to the input trajectory. Thus, the accuracy and repeatability of 6D motion was investigated and the phantom performance was characterized. Results: Evaluation of the 6D platform demonstrated translational RMSE values of 0.196 mm, 0.260 mm, and 0.101 mm over 20 mm in X and Y and 10 mm in Z, respectively, and rotational RMSE values of 0.068 degrees, 0.0611 degrees, and 0.095 degrees over 10 degrees of pitch, roll, and yaw, respectively. The robotic stage also effectively performed controlled 6D motions, as well as reproduced cranial trajectories over 15 minutes, with a maximal RMSE of 0.044 mm translationally and 0.036 degrees rotationally. Conclusion: This 6D robotic phantom has proven to be accurate under clinical standards and capable of reproducing tumor motion in 6D. Consequently, such a robotics device has the potential to serve as a more effective system for IGRT QA that involves both translational and

  20. IONIZATION IN ATMOSPHERES OF BROWN DWARFS AND EXTRASOLAR PLANETS. II. DUST-INDUCED COLLISIONAL IONIZATION

    SciTech Connect

    Helling, Ch.; Jardine, M.; Mokler, F.

    2011-08-10

    Observations have shown that continuous radio emission and also sporadic H{alpha} and X-ray emission are prominent in singular, low-mass objects later than spectral class M. These activity signatures are interpreted as being caused by coupling of an ionized atmosphere to the stellar magnetic field. What remains a puzzle, however, is the mechanism by which such a cool atmosphere can produce the necessary level of ionization. At these low temperatures, thermal gas processes are insufficient, but the formation of clouds sets in. Cloud particles can act as seeds for electron avalanches in streamers that ionize the ambient gas, and can lead to lightning and indirectly to magnetic field coupling, a combination of processes also expected for protoplanetary disks. However, the precondition is that the cloud particles are charged. We use results from DRIFT-PHOENIX model atmospheres to investigate collisional processes that can lead to the ionization of dust grains inside clouds. We show that ionization by turbulence-induced dust-dust collisions is the most efficient kinetic process. The efficiency is highest in the inner cloud where particles grow quickly and, hence, the dust-to-gas ratio is high. Dust-dust collisions alone are not sufficient to improve the magnetic coupling of the atmosphere inside the cloud layers, but the charges supplied either on grains or within the gas phase as separated electrons can trigger secondary nonlinear processes. Cosmic rays are likely to increase the global level of ionization, but their influence decreases if a strong, large-scale magnetic field is present as on brown dwarfs. We suggest that although thermal gas ionization declines in objects across the fully convective boundary, dust charging by collisional processes can play an important role in the lowest mass objects. The onset of atmospheric dust may therefore correlate with the anomalous X-ray and radio emission in atmospheres that are cool, but charged more than expected by pure

  1. Ambient Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Huang, Min-Zong; Yuan, Cheng-Hui; Cheng, Sy-Chyi; Cho, Yi-Tzu; Shiea, Jentaie

    2010-07-01

    Mass spectrometric ionization methods that operate under ambient conditions and require minimal or no sample pretreatment have attracted much attention in such fields as biomedicine, food safety, antiterrorism, pharmaceuticals, and environmental pollution. These technologies usually involve separate ionization and sample-introduction events, allowing independent control over each set of conditions. Ionization is typically performed under ambient conditions through use of existing electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) techniques. Rapid analyses of gas, liquid, and solid samples are possible with the adoption of various sample-introduction methods. This review sorts different ambient ionization techniques into two main subcategories, primarily on the basis of the ionization processes, that are further differentiated in terms of the approach used for sampling.

  2. Physics of Partially Ionized Plasmas

    NASA Astrophysics Data System (ADS)

    Krishan, Vinod

    2016-05-01

    Figures; Preface; 1. Partially ionized plasmas here and everywhere; 2. Multifluid description of partially ionized plasmas; 3. Equilibrium of partially ionized plasmas; 4. Waves in partially ionized plasmas; 5. Advanced topics in partially ionized plasmas; 6. Research problems in partially ionized plasmas; Supplementary matter; Index.

  3. The Milky Way's halo in 6D: Gaia's Radial Velocity Spectrometer performance

    NASA Astrophysics Data System (ADS)

    Seabroke, George; Cropper, Mark; Katz, David; Sartoretti, Paola; Panuzzo, Pasquale; Marchal, Olivier; Gueguen, Alain; Benson, Kevin; Dolding, Chris; Huckle, Howard; Smith, Mike; Baker, Steve

    2016-08-01

    Gaia's Radial Velocity Spectrometer (RVS) has been operating in routine phase for over one year since initial commissioning. RVS continues to work well but the higher than expected levels of straylight reduce the limiting magnitude. The end-of-mission radial-velocity (RV) performance requirement for G2V stars was 15 km s-1 at V = 16.5 mag. Instead, 15 km s-1 precision is achieved at 15 < V < 16 mag, consistent with simulations that predict a loss of 1.4 mag. Simulations also suggest that changes to Gaia's onboard software could recover ~0.14 mag of this loss. Consequently Gaia's onboard software was upgraded in April 2015. The status of this new commissioning period is presented, as well as the latest scientific performance of the on-ground processing of RVS spectra. We illustrate the implications of the RVS limiting magnitude on Gaia's view of the Milky Way's halo in 6D using the Gaia Universe Model Snapshot (GUMS).

  4. Degradation of Extracellular β-(1,3)(1,6)-d-Glucan by Botrytis cinerea

    PubMed Central

    Stahmann, K.-Peter; Pielken, Petra; Schimz, Karl-Ludwig; Sahm, Hermann

    1992-01-01

    During growth on glucose, Botrytis cinerea produced extracellular β-(1,3)(1,6)-d-glucan (cinerean), which formed an adhering capsule and slime. After glucose was exhausted from the medium, cinereanase activity increased from <0.4 to 30 U/liter, effecting a striking loss in the viscosity of the culture. Cinerean was cleaved into glucose and gentiobiose. Gentiobiose was then hydrolyzed to glucose. While cinereanase activity was strongest in the culture supernatant, gentiobiase activity was located mainly in the cell wall fraction. The addition of extra glucose or cycloheximide prevented the cinerean degradation caused by an effect on cinereanase formation. Cinerean degradation was accompanied by microconidiation and sclerotium formation. B. cinerea was found to grow on cinerean with the latter as its single carbon and energy source. In this case, cinerean degradation occurred during hyphal growth, and no microconidiation or sclerotium formation was observed. Growth experiments with various carbon sources indicated that cinerean had a positive effect on the formation of cinerean-degrading enzymes. Images PMID:16348789

  5. Determination of 6D workspaces of Gough-type parallel manipulator and comparison between different geometries

    SciTech Connect

    Merlet, J.P.

    1999-09-01

    The author considers in this paper a Gough-type parallel robot whose leg length values are constrained to lie within some fixed ranges and for which there may be mechanical limits for the motion of the passive joints. The purpose of this paper is to present algorithms to determine: the constant orientation workspace; all the possible locations of the center of the platform that can be reached with a fixed orientation; the total orientation workspace: all the possible locations of the center of the platform that can be reached with any orientation in a set defined by three ranges for the orientation angles; the inclusive orientation workspace: all the possible locations of the center of the platform that can be reached with at least one orientation among a set defined by three ranges for the orientation angles. Most of these algorithms are based on a basic methods: approximation of the results by a set of 3D or 6D boxes obtained from an initial estimation through a bisection process. The boxes in the result will either fully or partially lie inside the workspace: the bisection stops as soon as all the boxes that do not lie fully inside the workspace have a size that is lower than a fixed threshold. The paper includes a comparison between the workspace volumes of four different robot geometries, which shows that for robots of similar dimensions the joints layout has a large influence on the workspace volume.

  6. Inheritance of steroid-independent male sexual behavior in male offspring of B6D2F1 mice.

    PubMed

    McInnis, Christine M; Bonthuis, Paul J; Rissman, Emilie F; Park, Jin Ho

    2016-04-01

    The importance of gonadal steroids in modulating male sexual behavior is well established. Individual differences in male sexual behavior, independent of gonadal steroids, are prevalent across a wide range of species, including man. However, the genetic mechanisms underlying steroid-independent male sexual behavior are poorly understood. A high proportion of B6D2F1 hybrid male mice demonstrates steroid-independent male sexual behavior (identified as "maters"), providing a mouse model that opens up avenues of investigation into the mechanisms regulating male sexual behavior in the absence of gonadal hormones. Recent studies have revealed several proteins that play a significant factor in regulating steroid-independent male sexual behavior in B6D2F1 male mice, including amyloid precursor protein (APP), tau, and synaptophysin. The specific goals of our study were to determine whether steroid-independent male sexual behavior was a heritable trait by determining if it was dependent upon the behavioral phenotype of the B6D2F1 sire, and whether the differential expression of APP, tau, and synaptophysin in the medial preoptic area found in the B6D2F1 sires that did and did not mate after gonadectomy was similar to those found in their male offspring. After adult B6D2F1 male mice were bred with C57BL/6J female mice, they and their male offspring (BXB1) were orchidectomized and identified as either maters or "non-maters". A significant proportion of the BXB1 maters was sired only from B6D2F1 maters, indicating that the steroid-independent male sexual behavior behavioral phenotype of the B6D2F1 hybrid males, when crossed with C57BL/6J female mice, is inherited by their male offspring. Additionally, APP, tau, and synaptophysin were elevated in in the medial preoptic area in both the B6D2F1 and BXB1 maters relative to the B6D2F1 and BXB1 non-maters, respectively, suggesting a potential genetic mechanism for the inheritance of steroid-independent male sexual behavior. PMID

  7. Identification of Rab41/6d Effectors Provides an Explanation for the Differential Effects of Rab41/6d and Rab6a/a' on Golgi Organization.

    PubMed

    Liu, Shijie; Majeed, Waqar; Kudlyk, Tetyana; Lupashin, Vladimir; Storrie, Brian

    2016-01-01

    Unexpectedly, members of the Rab VI subfamily exhibit considerable variation in their effects on Golgi organization and trafficking. By fluorescence microscopy, neither depletion nor overexpression of the GDP-locked form of Rab6a/a', the first trans Golgi-associated Rab protein discovered, affects Golgi ribbon organization while, on the other hand, both Rab41/6d depletion and overexpression of GDP-locked form cause Golgi fragmentation into a cluster of punctate elements, suggesting that Rab41/6d has an active role in maintenance of Golgi ribbon organization. To establish a molecular basis for these differences, we screened for Rab41/6d interacting proteins by yeast two-hybrid assay. 155 non-repetitive hits were isolated and sequenced, and after searching in NCBI database, 102 different proteins and protein fragments were identified. None of these hits overlapped with any published Rab6a/a' effector. Eight putative Rab41 interactors involved in membrane trafficking were found. Significantly, these exhibited a preferential interaction with GTP- vs. GDP-locked Rab41/6d. Of the 8 hits, the dynactin 6, syntaxin 8, and Kif18A plasmids were the only ones expressing the full-length protein. Hence, these 3 proteins were selected for further study. We found that depletion of dynactin 6 or syntaxin 8, but not Kif18A, resulted in a fragmented Golgi apparatus that displayed a Rab41/6d knockdown phenotype, i.e., the Golgi apparatus was disrupted into a cluster of punctate Golgi elements. Co-immunoprecipation experiments verified that the interaction of dynactin 6 and syntaxin 8 with GTP-locked Rab41/6d was stronger than that with wild type Rab41/6d and least with the GDP-locked form. In contrast, co-immunoprecipitation interaction with Rab6a was greatest with the GDP-locked Rab6a, suggestive of a non-physiological interaction. In conclusion, we suggest that dynactin 6, a subunit of dynactin complex, the minus-end-directed, dynein motor, provides a sufficient molecular basis to

  8. Identification of Rab41/6d Effectors Provides an Explanation for the Differential Effects of Rab41/6d and Rab6a/a' on Golgi Organization

    PubMed Central

    Liu, Shijie; Majeed, Waqar; Kudlyk, Tetyana; Lupashin, Vladimir; Storrie, Brian

    2016-01-01

    Unexpectedly, members of the Rab VI subfamily exhibit considerable variation in their effects on Golgi organization and trafficking. By fluorescence microscopy, neither depletion nor overexpression of the GDP-locked form of Rab6a/a', the first trans Golgi-associated Rab protein discovered, affects Golgi ribbon organization while, on the other hand, both Rab41/6d depletion and overexpression of GDP-locked form cause Golgi fragmentation into a cluster of punctate elements, suggesting that Rab41/6d has an active role in maintenance of Golgi ribbon organization. To establish a molecular basis for these differences, we screened for Rab41/6d interacting proteins by yeast two-hybrid assay. 155 non-repetitive hits were isolated and sequenced, and after searching in NCBI database, 102 different proteins and protein fragments were identified. None of these hits overlapped with any published Rab6a/a' effector. Eight putative Rab41 interactors involved in membrane trafficking were found. Significantly, these exhibited a preferential interaction with GTP- vs. GDP-locked Rab41/6d. Of the 8 hits, the dynactin 6, syntaxin 8, and Kif18A plasmids were the only ones expressing the full-length protein. Hence, these 3 proteins were selected for further study. We found that depletion of dynactin 6 or syntaxin 8, but not Kif18A, resulted in a fragmented Golgi apparatus that displayed a Rab41/6d knockdown phenotype, i.e., the Golgi apparatus was disrupted into a cluster of punctate Golgi elements. Co-immunoprecipation experiments verified that the interaction of dynactin 6 and syntaxin 8 with GTP-locked Rab41/6d was stronger than that with wild type Rab41/6d and least with the GDP-locked form. In contrast, co-immunoprecipitation interaction with Rab6a was greatest with the GDP-locked Rab6a, suggestive of a non-physiological interaction. In conclusion, we suggest that dynactin 6, a subunit of dynactin complex, the minus-end-directed, dynein motor, provides a sufficient molecular basis to

  9. Semantic data association for planar features in outdoor 6D-SLAM using lidar

    NASA Astrophysics Data System (ADS)

    Ulas, C.; Temeltas, H.

    2013-05-01

    Simultaneous Localization and Mapping (SLAM) is a fundamental problem of the autonomous systems in GPS (Global Navigation System) denied environments. The traditional probabilistic SLAM methods uses point features as landmarks and hold all the feature positions in their state vector in addition to the robot pose. The bottleneck of the point-feature based SLAM methods is the data association problem, which are mostly based on a statistical measure. The data association performance is very critical for a robust SLAM method since all the filtering strategies are applied after a known correspondence. For point-features, two different but very close landmarks in the same scene might be confused while giving the correspondence decision when their positions and error covariance matrix are solely taking into account. Instead of using the point features, planar features can be considered as an alternative landmark model in the SLAM problem to be able to provide a more consistent data association. Planes contain rich information for the solution of the data association problem and can be distinguished easily with respect to point features. In addition, planar maps are very compact since an environment has only very limited number of planar structures. The planar features does not have to be large structures like building wall or roofs; the small plane segments can also be used as landmarks like billboards, traffic posts and some part of the bridges in urban areas. In this paper, a probabilistic plane-feature extraction method from 3DLiDAR data and the data association based on the extracted semantic information of the planar features is introduced. The experimental results show that the semantic data association provides very satisfactory result in outdoor 6D-SLAM.

  10. Device for detecting ionizing radiation

    SciTech Connect

    Anatychuk, L.I.; Kharitonov, J.P.; Kusniruk, V.F.; Meir, V.A.; Melnik, A.P.; Ponomarev, V.S.; Skakodub, V.A.; Sokolov, A.D.; Subbotin, V.G.; Zhukovsky, A.N.

    1980-10-28

    The present invention relates to ionizing radiation sensors, and , more particularly, to semiconductor spectrometers with thermoelectric cooling, and can most advantageously be used in mineral raw material exploration and evaluation under field conditions. The spectrometer comprises a vacuum chamber with an entrance window for passing the radiation therethrough. The vacuum chamber accommodates a thermoelectric cooler formed by a set of peltier elements. A heat conducting plate is mounted on the cold side of the thermoelectric cooler, and its hot side is provided with a radiator. Mounted on the heat conducting plate are sets of peltier elements, integral with the thermoelectric cooler and independent of one another. The peltier elements of these sets are stacked so as to develop the minimum temperature conditions on one set carrying a semiconductor detector and to provide the maximum refrigeration capacity conditions on the other set provided with the field-effect transistor mounted thereon.

  11. Analytical instruments, ionization sources, and ionization methods

    DOEpatents

    Atkinson, David A.; Mottishaw, Paul

    2006-04-11

    Methods and apparatus for simultaneous vaporization and ionization of a sample in a spectrometer prior to introducing the sample into the drift tube of the analyzer are disclosed. The apparatus includes a vaporization/ionization source having an electrically conductive conduit configured to receive sample particulate which is conveyed to a discharge end of the conduit. Positioned proximate to the discharge end of the conduit is an electrically conductive reference device. The conduit and the reference device act as electrodes and have an electrical potential maintained between them sufficient to cause a corona effect, which will cause at least partial simultaneous ionization and vaporization of the sample particulate. The electrical potential can be maintained to establish a continuous corona, or can be held slightly below the breakdown potential such that arrival of particulate at the point of proximity of the electrodes disrupts the potential, causing arcing and the corona effect. The electrical potential can also be varied to cause periodic arcing between the electrodes such that particulate passing through the arc is simultaneously vaporized and ionized. The invention further includes a spectrometer containing the source. The invention is particularly useful for ion mobility spectrometers and atmospheric pressure ionization mass spectrometers.

  12. Electron-Impact Total Ionization Cross Sections of Hydrocarbon Ions

    PubMed Central

    Irikura, Karl K.; Kim, Yong-Ki; Ali, M. A.

    2002-01-01

    The Binary-Encounter-Bethe (BEB) model for electron-impact total ionization cross sections has been applied to CH2+, CH3+, CH4+, C2H2+, C2H4+, C2H6+ and H3O+. The cross sections for the hydrocarbon ions are needed for modeling cool plasmas in fusion devices. No experimental data are available for direct comparison. Molecular constants to generate total ionization cross sections at arbitrary incident electron energies using the BEB formula are presented. A recent experimental result on the ionization of H3O+ is found to be almost 1/20 of the present theory at the cross section peak.

  13. The 6dF Galaxy Survey: bulk flows on 50-70 h-1 Mpc scales

    NASA Astrophysics Data System (ADS)

    Scrimgeour, Morag I.; Davis, Tamara M.; Blake, Chris; Staveley-Smith, Lister; Magoulas, Christina; Springob, Christopher M.; Beutler, Florian; Colless, Matthew; Johnson, Andrew; Jones, D. Heath; Koda, Jun; Lucey, John R.; Ma, Yin-Zhe; Mould, Jeremy; Poole, Gregory B.

    2016-01-01

    We measure the bulk flow of the local Universe using the 6dF Galaxy Survey peculiar velocity sample (6dFGSv), the largest and most homogeneous peculiar velocity sample to date. 6dFGSv is a Fundamental Plane sample of ˜104 peculiar velocities covering the whole Southern hemisphere for galactic latitude |b| > 10°, out to redshift z = 0.0537. We apply the `minimum variance' bulk flow weighting method, which allows us to make a robust measurement of the bulk flow on scales of 50 and 70 h-1 Mpc. We investigate and correct for potential bias due to the lognormal velocity uncertainties, and verify our method by constructing Λ cold dark matter (ΛCDM) 6dFGSv mock catalogues incorporating the survey selection function. For a hemisphere of radius 50 h-1 Mpc we find a bulk flow amplitude of U = 248 ± 58 km s-1 in the direction (l, b) = (318° ± 20°, 40° ± 13°), and for 70 h-1 Mpc we find U = 243 ± 58 km s-1, in the same direction. Our measurement gives us a constraint on σ8 of 1.01^{+1.07}_{-0.58}. Our results are in agreement with other recent measurements of the direction of the bulk flow, and our measured amplitude is consistent with a ΛCDM prediction.

  14. A Moment Equation Approach to a Muon Collider Cooling Lattice

    SciTech Connect

    Celata, C.M.; Sessler, A.M.; Lee, P.B.; Shadwick, B.A.; Wurtele, J.S.

    1998-06-01

    Equations are derived which describe the evolution of the second order moments of the beam distribution function in the ionization cooling section of a muon collider. Ionization energy loss, multiple scattering, and magnetic fields have been included, but forces are linearized. A computer code using the equations agrees well with tracking calculations. The code is extremely fast, and can be used for preliminary design, where such issues as beam halo, which must be explored using a tracking code, are not the focus.

  15. "Anomalous" excitation in hydrogen-bonded molecular crystals - a Raman scattering study of specifically deuterated acetanilide (C 6D 5-CONH-CD 3)

    NASA Astrophysics Data System (ADS)

    Sauvajol, J. L.; De Nunzio, G.; Almairac, R.; Moret, J.; Barthés, M.; Bataillon, Place E.

    1991-01-01

    The focus of experimental and theoretical works about crystalline Acetanilide has been the "anomalous" temperature-dependent ir absorption and Raman peaks at about 1650 cm -1 and the multiband structure in the N-H stretch region. A lively discussion about the assignment of these "anomalous" bands has arisen and is still in progress. The present Raman experiments should be placed in this context as an attempt to identify the molecular degrees of freedom which originate the "anomalous" bands. In this aim Raman experiments have been performed on specifically deuterated Acetanilide [C 6D 5-CONH-CD 3] single crystal in the low-frequency (phonon) and C=O stretching regions. On cooling a distinct band at about 1495 cm -1 increases in intensity. We assign this peak to the equivalent of the 1650 cm -1 band in Acetanilide. The temperature dependence of this Raman line was studied. The results are discussed in the light of the models proposed to explain the anomalous behaviour of the 1650 cm -1 Raman line in Acetanilide.

  16. Hybrid radiator cooling system

    DOEpatents

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  17. Biological Effects of Ionizing Radiation

    DOE R&D Accomplishments Database

    Ingram, M.; Mason, W. B.; Whipple, G. H.; Howland, J. W.

    1952-04-07

    This report presents a review of present knowledge and concepts of the biological effects of ionizing radiations. Among the topics discussed are the physical and chemical effects of ionizing radiation on biological systems, morphological and physiological changes observed in biological systems subjected to ionizing radiations, physiological changes in the intact animal, latent changes following exposure of biological systems to ionizing radiations, factors influencing the biological response to ionizing radiation, relative effects of various ionizing radiations, and biological dosimetry.

  18. Hydrogen-filled RF Cavities for Muon Beam Cooling

    SciTech Connect

    CHARLES, Ankenbrandt

    2009-04-17

    Ionization cooling requires low-Z energy absorbers immersed in a strong magnetic field and high-gradient, large-aperture RF cavities to be able to cool a muon beam as quickly as the short muon lifetime requires. RF cavities that operate in vacuum are vulnerable to dark-current- generated breakdown, which is exacerbated by strong magnetic fields, and they require extra safety windows that degrade cooling, to separate RF regions from hydrogen energy absorbers. RF cavities pressurized with dense hydrogen gas will be developed that use the same gas volume to provide the energy absorber and the RF acceleration needed for ionization cooling. The breakdown suppression by the dense gas will allow the cavities to operate in strong magnetic fields. Measurements of the operation of such a cavity will be made as functions of external magnetic field and charged particle beam intensity and compared with models to understand the characteristics of this technology and to develop mitigating strategies if necessary.

  19. Distinct subcellular localization of alternative splicing variants of EFA6D, a guanine nucleotide exchange factor for Arf6, in the mouse brain.

    PubMed

    Fukaya, Masahiro; Ohta, Shingo; Hara, Yoshinobu; Tamaki, Hideaki; Sakagami, Hiroyuki

    2016-09-01

    EFA6D (guanine nucleotide exchange factor for ADP-ribosylation factor 6 [Arf6]D) is also known as EFA6R, Psd3, and HCA67. It is the fourth member of the EFA6 family with guanine nucleotide exchange activity for Arf6, a small guanosine triphosphatase (GTPase) that regulates endosomal trafficking and actin cytoskeleton remodeling. We propose a classification and nomenclature of 10 EFA6D variants deposited in the GenBank database as EFA6D1a, 1b, 1c, 1d, 1s, 2a, 2b, 2c, 2d, and 2s based on the combination of N-terminal and C-terminal insertions. Polymerase chain reaction analysis showed the expression of all EFA6D variants except for variants a and d in the adult mouse brain. Immunoblotting analysis with novel variant-specific antibodies showed the endogenous expression of EFA6D1b, EFA6D1c, and EFA6D1s at the protein level, with the highest expression being EFA6D1s, in the brain. Immunoblotting analysis of forebrain subcellular fractions showed the distinct subcellular distribution of EFA6D1b/c and EFA6D1s. The immunohistochemical analysis revealed distinct but overlapping immunoreactive patterns between EFA6D1b/c and EFA6D1s in the mouse brain. In immunoelectron microscopic analyses of the hippocampal CA3 region, EFA6D1b/c was present predominantly in the mossy fiber axons of dentate granule cells, whereas EFA6D1s was present abundantly in the cell bodies, dendritic shafts, and spines of hippocampal pyramidal cells. These results provide the first anatomical evidence suggesting the functional diversity of EFA6D variants, particularly EFA6D1b/c and EFA6D1s, in neurons. J. Comp. Neurol. 524:2531-2552, 2016. © 2016 Wiley Periodicals, Inc. PMID:27241101

  20. Wedge Absorber Design for the Muon Ionisation Cooling Experiment

    SciTech Connect

    Rogers, C.; Snopok, P.; Coney, L.; Jansson, A.; /Fermilab

    2010-05-01

    In the Muon Ionisation Cooling Experiment (MICE), muons are cooled by ionisation cooling. Muons are passed through material, reducing the total momentum of the beam. This results in a decrease in transverse emittance and a slight increase in longitudinal emittance, but overall reduction of 6d beam emittance. In emittance exchange, a dispersive beam is passed through wedge-shaped absorbers. Muons with higher energy pass through more material, resulting in a reduction in longitudinal emittance as well as transverse emittance. We consider the cooling performance of different wedge materials and geometries and propose a set of measurements that would be made in MICE.We outline the resources these measurements would require and detail some constraints that guide the choice of wedge parameters.

  1. Muon Cooling R&D Progress in the US

    NASA Astrophysics Data System (ADS)

    Li, Derun

    2008-02-01

    Muon ionization cooling R&D is important for a neutrino factory and future muon collider. In addition to theoretical studies, much progress has been made in muon cooling channel hardware R&D since NuFact-2006. This paper reports the progress on hardware R&D that includes experimental RF test programs using 805-MHz RF cavity, superconducting (SC) solenoids (coupling coils), 201-MHz RF cavity, liquid hydrogen absorber and MUCOOL Test Area (MTA) experiment preparation for beam tests.

  2. Six-degree-of-freedom program to optimize simulated trajectories (6D POST). Volume 1: Formulation manual

    NASA Technical Reports Server (NTRS)

    Brauer, G. L.; Habeger, A. R.; Stevenson, R.

    1974-01-01

    The basic equations and models used in a computer program (6D POST) to optimize simulated trajectories with six degrees of freedom were documented. The 6D POST program was conceived as a direct extension of the program POST, which dealt with point masses, and considers the general motion of a rigid body with six degrees of freedom. It may be used to solve a wide variety of atmospheric flight mechanics and orbital transfer problems for powered or unpowered vehicles operating near a rotating oblate planet. Its principal features are: an easy to use NAMELIST type input procedure, an integrated set of Flight Control System (FCS) modules, and a general-purpose discrete parameter targeting and optimization capability. It was written in FORTRAN 4 for the CDC 6000 series computers.

  3. 6D F-theory models and elliptically fibered Calabi-Yau threefolds over semi-toric base surfaces

    NASA Astrophysics Data System (ADS)

    Martini, Gabriella; Taylor, Washington

    2015-06-01

    We carry out a systematic study of a class of 6D F-theory models and associated Calabi-Yau threefolds that are constructed using base surfaces with a generalization of toric structure. In particular, we determine all smooth surfaces with a structure invariant under a single C∗ action (sometimes called "T-varieties" in the mathematical literature) that can act as bases for an elliptic fibration with section of a Calabi-Yau threefold. We identify 162,404 distinct bases, which include as a subset the previously studied set of strictly toric bases. Calabi-Yau threefolds constructed in this fashion include examples with previously unknown Hodge numbers. There are also bases over which the generic elliptic fibration has a Mordell-Weil group of sections with nonzero rank, corresponding to non-Higgsable U(1) factors in the 6D supergravity model; this type of structure does not arise for generic elliptic fibrations in the purely toric context.

  4. Comparing the 2MTF and 6dFGS Peculiar Velocity Surveys to models from redshift surveys

    NASA Astrophysics Data System (ADS)

    Springob, Christopher M.; Hong, Tao; Magoulas, Christina; Colless, Matthew; Staveley-Smith, Lister; Erdogdu, Pirin; Jones, D. Heath; Lucey, John R.; Masters, Karen; Mould, Jeremy R.; Jarrett, Tom; Koribalski, Baerbel; Macri, Lucas M.; Scrimgeour, Morag

    2015-01-01

    The 6dF Galaxy Survey (6dFGS) and 2MASS Tully-Fisher Survey (2MTF) are large galaxy peculiar velocity surveys of the local universe, providing distances and peculiar velocities for thousands of galaxies, derived via the Fundamental Plane and Tully-Fisher relations respectively. We compare these observed velocity fields to reconstructed peculiar velocity field models derived from redshift surveys such as the 2MASS Redshift Survey (2MRS) and the IRAS Point Source Redshift Survey (PSCz), addressing the question of whether the galaxy distribution traces the matter distribution, and whether the observed velocity fields include a "residual bulk flow" not predicted by the models. This research was conducted by the Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO), through project number CE110001020.

  5. The characteristic of evaporative cooling magnet for ECRIS.

    PubMed

    Xiong, B; Ruan, L; Gu, G B; Lu, W; Zhang, X Z; Zhan, W L

    2016-02-01

    Compared with traditional de-ionized pressurized-water cooled magnet of ECRIS, evaporative cooling magnet has some special characteristics, such as high cooling efficiency, simple maintenance, and operation. The analysis is carried out according to the design and operation of LECR4 (Lanzhou Electron Cyclotron Resonance ion source No. 4, since July 2013), whose magnet is cooled by evaporative cooling technology. The insulation coolant replaces the de-ionized pressurized-water to absorb the heat of coils, and the physical and chemical properties of coolant remain stable for a long time with no need for purification or filtration. The coils of magnet are immersed in the liquid coolant. For the higher cooling efficiency of coolant, the current density of coils can be greatly improved. The heat transfer process executes under atmospheric pressure, and the temperature of coils is lower than 70 °C when the current density of coils is 12 A/mm(2). On the other hand, the heat transfer temperature of coolant is about 50 °C, and the heat can be transferred to fresh air which can save cost of water cooling system. Two years of LECR4 stable operation show that evaporative cooling technology can be used on magnet of ECRIS, and the application advantages are very obvious. PMID:26931937

  6. The characteristic of evaporative cooling magnet for ECRIS

    NASA Astrophysics Data System (ADS)

    Xiong, B.; Ruan, L.; Gu, G. B.; Lu, W.; Zhang, X. Z.; Zhan, W. L.

    2016-02-01

    Compared with traditional de-ionized pressurized-water cooled magnet of ECRIS, evaporative cooling magnet has some special characteristics, such as high cooling efficiency, simple maintenance, and operation. The analysis is carried out according to the design and operation of LECR4 (Lanzhou Electron Cyclotron Resonance ion source No. 4, since July 2013), whose magnet is cooled by evaporative cooling technology. The insulation coolant replaces the de-ionized pressurized-water to absorb the heat of coils, and the physical and chemical properties of coolant remain stable for a long time with no need for purification or filtration. The coils of magnet are immersed in the liquid coolant. For the higher cooling efficiency of coolant, the current density of coils can be greatly improved. The heat transfer process executes under atmospheric pressure, and the temperature of coils is lower than 70 °C when the current density of coils is 12 A/mm2. On the other hand, the heat transfer temperature of coolant is about 50 °C, and the heat can be transferred to fresh air which can save cost of water cooling system. Two years of LECR4 stable operation show that evaporative cooling technology can be used on magnet of ECRIS, and the application advantages are very obvious.

  7. Progress on Superconducting Magnets for the MICE Cooling Channel

    SciTech Connect

    Green, Michael A; Virostek, Steve P.; Li, Derun; Zisman, Michael S.; Wang, Li; Pan, Heng; Wu, Hong; Guo, XingLong; Xu, FengYu; Liu, X. K.; Zheng, S. X.; Bradshaw, Thomas; Baynham, Elwyn; Cobb, John; Lau, Wing; Lau, Peter; Yang, Stephanie Q.

    2009-09-09

    The muon ionization cooling experiment (MICE) consists of a target, a beam line, a pion decay channel, the MICE cooling channel. Superconducting magnets are used in the pion decay channel and the MICE cooling channel. This report describes the MICE cooling channel magnets and the progress in the design and fabrication of these magnets. The MICE cooling channel consists of three types of superconducting solenoids; the spectrometer solenoids, the coupling solenoids and the focusing solenoids. The three types of magnets are being fabricated in he United States, China, and the United Kingdom respectively. The spectrometer magnets are used to analyze the muon beam before and after muon cooling. The coupling magnets couple the focusing sections and keep the muon beam contained within the iris of the RF cavities that re used to recover the muon momentum lost during ionization cooling. The focusing magnets focus the muon beam in the center of a liquid hydrogen absorber. The first of the cooling channel magnets will be operational in MICE in the spring of 2010.

  8. Adiabatic cooling of antiprotons.

    PubMed

    Gabrielse, G; Kolthammer, W S; McConnell, R; Richerme, P; Kalra, R; Novitski, E; Grzonka, D; Oelert, W; Sefzick, T; Zielinski, M; Fitzakerley, D; George, M C; Hessels, E A; Storry, C H; Weel, M; Müllers, A; Walz, J

    2011-02-18

    Adiabatic cooling is shown to be a simple and effective method to cool many charged particles in a trap to very low temperatures. Up to 3×10(6) p are cooled to 3.5 K-10(3) times more cold p and a 3 times lower p temperature than previously reported. A second cooling method cools p plasmas via the synchrotron radiation of embedded e(-) (with many fewer e(-) than p in preparation for adiabatic cooling. No p are lost during either process-a significant advantage for rare particles. PMID:21405511

  9. Adiabatic Cooling of Antiprotons

    SciTech Connect

    Gabrielse, G.; Kolthammer, W. S.; McConnell, R.; Richerme, P.; Kalra, R.; Novitski, E.; Oelert, W.; Grzonka, D.; Sefzick, T.; Zielinski, M.; Fitzakerley, D.; George, M. C.; Hessels, E. A.; Storry, C. H.; Weel, M.; Muellers, A.; Walz, J.

    2011-02-18

    Adiabatic cooling is shown to be a simple and effective method to cool many charged particles in a trap to very low temperatures. Up to 3x10{sup 6} p are cooled to 3.5 K--10{sup 3} times more cold p and a 3 times lower p temperature than previously reported. A second cooling method cools p plasmas via the synchrotron radiation of embedded e{sup -} (with many fewer e{sup -} than p) in preparation for adiabatic cooling. No p are lost during either process--a significant advantage for rare particles.

  10. A Charge Separation Study to Enable the Design of a Complete Muon Cooling Channel

    SciTech Connect

    Yoshikawa, C.; Ankenbrandt, Charles M.; Johnson, Rolland P.; Derbenev, Yaroslav; Morozov, Vasiliy; Neuffer, David; Yonehara, K.

    2013-12-01

    The most promising designs for 6D muon cooling channels operate on a specific sign of electric charge. In particular, the Helical Cooling Channel (HCC) and Rectilinear RFOFO designs are the leading candidates to become the baseline 6D cooling channel in the Muon Accelerator Program (MAP). Time constraints prevented the design of a realistic charge separator, so a simplified study was performed to emulate the effects of charge separation on muons exiting the front end of a muon collider. The output of the study provides particle distributions that the competing designs will use as input into their cooling channels. We report here on the study of the charge separator that created the simulated particles.

  11. Use of the BrainLAB ExacTrac X-Ray 6D system in image-guided radiotherapy.

    PubMed

    Jin, Jian-Yue; Yin, Fang-Fang; Tenn, Stephen E; Medin, Paul M; Solberg, Timothy D

    2008-01-01

    The ExacTrac X-Ray 6D image-guided radiotherapy (IGRT) system will be described and its performance evaluated. The system is mainly an integration of 2 subsystems: (1) an infrared (IR)-based optical positioning system (ExacTrac) and (2) a radiographic kV x-ray imaging system (X-Ray 6D). The infrared system consists of 2 IR cameras, which are used to monitor reflective body markers placed on the patient's skin to assist in patient initial setup, and an IR reflective reference star, which is attached to the treatment couch and can assist in couch movement with spatial resolution to better than 0.3 mm. The radiographic kV devices consist of 2 oblique x-ray imagers to obtain high-quality radiographs for patient position verification and adjustment. The position verification is made by fusing the radiographs with the simulation CT images using either 3 degree-of-freedom (3D) or 6 degree-of-freedom (6D) fusion algorithms. The position adjustment is performed using the infrared system according to the verification results. The reliability of the fusion algorithm will be described based on phantom and patient studies. The results indicated that the 6D fusion method is better compared to the 3D method if there are rotational deviations between the simulation and setup positions. Recently, the system has been augmented with the capabilities for image-guided positioning of targets in motion due to respiration and for gated treatment of those targets. The infrared markers provide a respiratory signal for tracking and gating of the treatment beam, with the x-ray system providing periodic confirmation of patient position relative to the gating window throughout the duration of the gated delivery. PMID:18456164

  12. Use of the BrainLAB ExacTrac X-Ray 6D System in Image-Guided Radiotherapy

    SciTech Connect

    Jin, J.-Y. Yin Fangfang; Tenn, Stephen E.; Medin, Paul M.; Solberg, Timothy D.

    2008-07-01

    The ExacTrac X-Ray 6D image-guided radiotherapy (IGRT) system will be described and its performance evaluated. The system is mainly an integration of 2 subsystems: (1) an infrared (IR)-based optical positioning system (ExacTrac) and (2) a radiographic kV x-ray imaging system (X-Ray 6D). The infrared system consists of 2 IR cameras, which are used to monitor reflective body markers placed on the patient's skin to assist in patient initial setup, and an IR reflective reference star, which is attached to the treatment couch and can assist in couch movement with spatial resolution to better than 0.3 mm. The radiographic kV devices consist of 2 oblique x-ray imagers to obtain high-quality radiographs for patient position verification and adjustment. The position verification is made by fusing the radiographs with the simulation CT images using either 3 degree-of-freedom (3D) or 6 degree-of-freedom (6D) fusion algorithms. The position adjustment is performed using the infrared system according to the verification results. The reliability of the fusion algorithm will be described based on phantom and patient studies. The results indicated that the 6D fusion method is better compared to the 3D method if there are rotational deviations between the simulation and setup positions. Recently, the system has been augmented with the capabilities for image-guided positioning of targets in motion due to respiration and for gated treatment of those targets. The infrared markers provide a respiratory signal for tracking and gating of the treatment beam, with the x-ray system providing periodic confirmation of patient position relative to the gating window throughout the duration of the gated delivery.

  13. Film cooling enhancement with surface restructure

    NASA Astrophysics Data System (ADS)

    Chen, Shuping

    Discrete-hole film cooling is used extensively in turbine components. In past decades, many research works concerning this technique have been published. Recently, efforts have been directed at seeking technologies that would increase film cooling effectiveness. Particularly, surface reshaping through protective coatings, such as a thermal barrier coating (TBC), is very attractive to turbine designers because extra machining work is not needed for its application. In the present work, film cooling enhancement with surface restructure is experimentally studied using an infrared (IR) imaging technique. The first surface structure studied is the surface with flow-aligned blockers. The studied configurations include single-hole and three-hole-row structures. The single-hole case is used for studying the effects of blocker design parameters, which include blocker height (0.2D, 0.4D, and 0.6D), distance between two neighboring blockers (0.8D, D, and 1.2D), blocker length (2", 4", and 6"), and blowing ratio M (0.43 and 0.93). The design with the best performance is chosen for the three-hole-row cases. The second surface shape studied, is the so-called upstream ramp, which is placed in front of a row of film cooling holes. Investigated geometrical parameters include upstream ramp angles (8.5°, 15°, and 24°) and blowing ratio M (0.29, 0.43, 0.57, 0.93, and 1.36). Detailed local film cooling effectiveness and heat transfer coefficient are measured using an IR imaging technique. The third film cooling concept is the so-called trenched film cooling holes, i.e., film cooling holes sitting in a transverse groove. The film cooling structure for this experimental test consists of a three-hole row embedded in a trench 0.5D in depth and 2D in width, where D is the diameter of the holes. Five blowing ratios (0.29, 0.43, 0.57, 0.93, and 1.36) are tested. Based on the tested results, the three film cooling schemes are also compared. To implement the experimental work, a test system

  14. Unusual magnetic and transport properties of oxygen deficient Sr2Fe1-xCoxMoO6-d

    NASA Astrophysics Data System (ADS)

    Chang, Hong; García-Hernández, Mar; Alonso, Jose Antonio

    2006-10-01

    In the title compounds the oxygen voids have a significant influence over the transport properties, compared with the parent stoichiometric compounds (Sr2FeMoO6 and Sr2CoMoO6) where the oxygen defects have little impact on the crystallographic and magnetic properties. For Sr2FeMoO6-d and Sr2Fe0.95Co0.05MoO6-d, the oxygen voids simply decrease the magnetoresistance (MR) without altering the contours, and for x ⩾0.1 at the expense of the decreased low field MR, the oxygen voids enhance MR at high applied field, which is 6%-8% larger than the parent compounds for 0.2⩽x⩽0.7. Remarkably enough, the antiferromagnetic Sr2Fe0.1Co0.9MoO6-d exhibits record negative magnetoresistance ratio MR =((R(H,T)-R(0,T))/R(0,T))×100% as high as 99%.

  15. "Magic" Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Trimpin, Sarah

    2016-01-01

    The systematic study of the temperature and pressure dependence of matrix-assisted ionization (MAI) led us to the discovery of the seemingly impossible, initially explained by some reviewers as either sleight of hand or the misinterpretation by an overzealous young scientist of results reported many years before and having little utility. The "magic" that we were attempting to report was that with matrix assistance, molecules, at least as large as bovine serum albumin (66 kDa), are lifted into the gas phase as multiply charged ions simply by exposure of the matrix:analyte sample to the vacuum of a mass spectrometer. Applied heat, a laser, or voltages are not necessary to achieve charge states and ion abundances only previously observed with electrospray ionization (ESI). The fundamentals of how solid phase volatile or nonvolatile compounds are converted to gas-phase ions without added energy currently involves speculation providing a great opportunity to rethink mechanistic understanding of ionization processes used in mass spectrometry. Improved understanding of the mechanism(s) of these processes and their connection to ESI and matrix-assisted laser desorption/ionization may provide opportunities to further develop new ionization strategies for traditional and yet unforeseen applications of mass spectrometry. This Critical Insights article covers developments leading to the discovery of a seemingly magic ionization process that is simple to use, fast, sensitive, robust, and can be directly applied to surface characterization using portable or high performance mass spectrometers.

  16. "Magic" Ionization Mass Spectrometry.

    PubMed

    Trimpin, Sarah

    2016-01-01

    The systematic study of the temperature and pressure dependence of matrix-assisted ionization (MAI) led us to the discovery of the seemingly impossible, initially explained by some reviewers as either sleight of hand or the misinterpretation by an overzealous young scientist of results reported many years before and having little utility. The “magic” that we were attempting to report was that with matrix assistance, molecules, at least as large as bovine serum albumin (66 kDa), are lifted into the gas phase as multiply charged ions simply by exposure of the matrix:analyte sample to the vacuum of a mass spectrometer. Applied heat, a laser, or voltages are not necessary to achieve charge states and ion abundances only previously observed with electrospray ionization (ESI). The fundamentals of how solid phase volatile or nonvolatile compounds are converted to gas-phase ions without added energy currently involves speculation providing a great opportunity to rethink mechanistic understanding of ionization processes used in mass spectrometry. Improved understanding of the mechanism(s) of these processes and their connection to ESI and matrix-assisted laser desorption/ionization may provide opportunities to further develop new ionization strategies for traditional and yet unforeseen applications of mass spectrometry. This Critical Insights article covers developments leading to the discovery of a seemingly magic ionization process that is simple to use, fast, sensitive, robust, and can be directly applied to surface characterization using portable or high performance mass spectrometers. PMID:26486514

  17. Alkali metal ionization detector

    DOEpatents

    Bauerle, James E.; Reed, William H.; Berkey, Edgar

    1978-01-01

    Variations in the conventional filament and collector electrodes of an alkali metal ionization detector, including the substitution of helical electrode configurations for either the conventional wire filament or flat plate collector; or, the substitution of a plurality of discrete filament electrodes providing an in situ capability for transferring from an operationally defective filament electrode to a previously unused filament electrode without removing the alkali metal ionization detector from the monitored environment. In particular, the helical collector arrangement which is coaxially disposed about the filament electrode, i.e. the thermal ionizer, provides an improved collection of positive ions developed by the filament electrode. The helical filament design, on the other hand, provides the advantage of an increased surface area for ionization of alkali metal-bearing species in a monitored gas environment as well as providing a relatively strong electric field for collecting the ions at the collector electrode about which the helical filament electrode is coaxially positioned. Alternatively, both the filament and collector electrodes can be helical. Furthermore, the operation of the conventional alkali metal ionization detector as a leak detector can be simplified as to cost and complexity, by operating the detector at a reduced collector potential while maintaining the sensitivity of the alkali metal ionization detector adequate for the relatively low concentration of alkali vapor and aerosol typically encountered in leak detection applications.

  18. Sex- and dose-dependent effects of calcium ion irradiation on behavioral performance of B6D2F1 mice during contextual fear conditioning training

    NASA Astrophysics Data System (ADS)

    Raber, Jacob; Weber, Sydney J.; Kronenberg, Amy; Turker, Mitchell S.

    2016-06-01

    The space radiation environment includes energetic charged particles that may impact behavioral and cognitive performance. The relationship between the dose and the ionization density of the various types of charged particles (expressed as linear energy transfer or LET), and cognitive performance is complex. In our earlier work, whole body exposure to 28Si ions (263 MeV/n, LET = 78keV / μ m ; 1.6 Gy) affected contextual fear memory in C57BL/6J × DBA2/J F1 (B6D2F1) mice three months following irradiation but this was not the case following exposure to 48Ti ions (1 GeV/n, LET = 107keV / μ m ; 0.2 or 0.4 Gy). As an increased understanding of the impact of charged particle exposures is critical for assessment of risk to the CNS of astronauts during and following missions, in this study we used 40Ca ion beams (942 MeV/n, LET = 90keV / μm) to determine the behavioral and cognitive effects for the LET region between that of Si ions and Ti ions. 40Ca ion exposure reduced baseline activity in a novel environment in a dose-dependent manner, which suggests reduced motivation to explore and/or a diminished level of curiosity in a novel environment. In addition, exposure to 40Ca ions had sex-dependent effects on response to shock. 40Ca ion irradiation reduced the response to shock in female, but not male, mice. In contrast, 40Ca ion irradiation did not affect fear learning, memory, or extinction of fear memory for either gender at the doses employed in this study. Thus 40Ca ion irradiation affected behavioral, but not cognitive, performance. The effects of 40Ca ion irradiation on behavioral performance are relevant, as a combination of novelty and aversive environmental stimuli is pertinent to conditions experienced by astronauts during and following space missions.

  19. Sex- and dose-dependent effects of calcium ion irradiation on behavioral performance of B6D2F1 mice during contextual fear conditioning training.

    PubMed

    Raber, Jacob; Weber, Sydney J; Kronenberg, Amy; Turker, Mitchell S

    2016-06-01

    The space radiation environment includes energetic charged particles that may impact behavioral and cognitive performance. The relationship between the dose and the ionization density of the various types of charged particles (expressed as linear energy transfer or LET), and cognitive performance is complex. In our earlier work, whole body exposure to (28)Si ions (263 MeV/n, LET=78keV/μm; 1.6 Gy) affected contextual fear memory in C57BL/6J × DBA2/J F1 (B6D2F1) mice three months following irradiation but this was not the case following exposure to (48)Ti ions (1 GeV/n, LET=107keV/μm; 0.2 or 0.4 Gy). As an increased understanding of the impact of charged particle exposures is critical for assessment of risk to the CNS of astronauts during and following missions, in this study we used (40)Ca ion beams (942 MeV/n, LET=90keV/μm) to determine the behavioral and cognitive effects for the LET region between that of Si ions and Ti ions. (40)Ca ion exposure reduced baseline activity in a novel environment in a dose-dependent manner, which suggests reduced motivation to explore and/or a diminished level of curiosity in a novel environment. In addition, exposure to (40)Ca ions had sex-dependent effects on response to shock. (40)Ca ion irradiation reduced the response to shock in female, but not male, mice. In contrast, (40)Ca ion irradiation did not affect fear learning, memory, or extinction of fear memory for either gender at the doses employed in this study. Thus (40)Ca ion irradiation affected behavioral, but not cognitive, performance. The effects of (40)Ca ion irradiation on behavioral performance are relevant, as a combination of novelty and aversive environmental stimuli is pertinent to conditions experienced by astronauts during and following space missions. PMID:27345201

  20. Liquid cooled garments

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Liquid cooled garments employed in several applications in which severe heat is encountered are discussed. In particular, the use of the garments to replace air line cooling units in a variety of industrial processing situations is discussed.

  1. Debuncher cooling performance

    SciTech Connect

    Derwent, P.F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven; /Fermilab

    2005-11-01

    We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz.

  2. Debuncher Cooling Performance

    SciTech Connect

    Derwent, P. F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven

    2006-03-20

    We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz.

  3. Liquid-Cooled Garment

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.

  4. Radial turbine cooling

    NASA Astrophysics Data System (ADS)

    Roelke, Richard J.

    The technology of high temperature cooled radial turbines is reviewed. Aerodynamic performance considerations are described. Heat transfer and structural analysis are addressed, and in doing so the following topics are covered: cooling considerations, hot side convection, coolant side convection, and rotor mechanical analysis. Cooled rotor concepts and fabrication are described, and the following are covered in this context: internally cooled rotor, hot isostatic pressure bonded rotor, laminated rotor, split blade rotor, and the NASA radial turbine program.

  5. Radial turbine cooling

    NASA Technical Reports Server (NTRS)

    Roelke, Richard J.

    1992-01-01

    The technology of high temperature cooled radial turbines is reviewed. Aerodynamic performance considerations are described. Heat transfer and structural analysis are addressed, and in doing so the following topics are covered: cooling considerations, hot side convection, coolant side convection, and rotor mechanical analysis. Cooled rotor concepts and fabrication are described, and the following are covered in this context: internally cooled rotor, hot isostatic pressure bonded rotor, laminated rotor, split blade rotor, and the NASA radial turbine program.

  6. Data center cooling system

    DOEpatents

    Chainer, Timothy J; Dang, Hien P; Parida, Pritish R; Schultz, Mark D; Sharma, Arun

    2015-03-17

    A data center cooling system may include heat transfer equipment to cool a liquid coolant without vapor compression refrigeration, and the liquid coolant is used on a liquid cooled information technology equipment rack housed in the data center. The system may also include a controller-apparatus to regulate the liquid coolant flow to the liquid cooled information technology equipment rack through a range of liquid coolant flow values based upon information technology equipment temperature thresholds.

  7. Controlled Rate Cooling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Controlled-rate cooling is one of several techniques available for the long-term storage of plants in liquid nitrogen. In this technique samples are slowly cooled to an intermediate temperature and then plunged in liquid nitrogen. Controlled rate cooling is based on osmotic regulation of cell conte...

  8. Stochastic cooling in RHIC

    SciTech Connect

    Brennan,J.M.; Blaskiewicz, M. M.; Severino, F.

    2009-05-04

    After the success of longitudinal stochastic cooling of bunched heavy ion beam in RHIC, transverse stochastic cooling in the vertical plane of Yellow ring was installed and is being commissioned with proton beam. This report presents the status of the effort and gives an estimate, based on simulation, of the RHIC luminosity with stochastic cooling in all planes.

  9. Fuel cell with ionization membrane

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T. (Inventor)

    2007-01-01

    A fuel cell is disclosed comprising an ionization membrane having at least one area through which gas is passed, and which ionizes the gas passing therethrough, and a cathode for receiving the ions generated by the ionization membrane. The ionization membrane may include one or more openings in the membrane with electrodes that are located closer than a mean free path of molecules within the gas to be ionized. Methods of manufacture are also provided.

  10. Cooling apparatus for water-cooled engines

    SciTech Connect

    Fujikawa, T.; Tamba, S.

    1986-05-20

    A cooling apparatus is described for a water-cooled internal combustion engine including a shaft that rotates when the engine is running, the apparatus comprising a centrifugal fan adapted to be connected to and rotated by the shaft, the fan having an intake air port and a discharge air opening, a rotary screen adapted to be operatively connected to and rotated by the shaft, the screen being disposed in the intake air port, a cooling radiator, a spiral-shaped duct connecting the radiator with the discharge air opening, and separating means on the duct, the separating means comprising an opening formed in the outer wall of the duct.

  11. The Cooling of a Liquid Absorber using a Small Cooler

    SciTech Connect

    Baynham, D.E.; Bradshaw, T.W.; Green, M.A.; Ishimoto, S.; Liggins, N.

    2005-08-24

    This report discusses the use of small cryogenic coolers for cooling the Muon Ionization Cooling Experiment (MICE) liquid cryogen absorbers. Since the absorber must be able contain liquid helium as well liquid hydrogen, the characteristics of the available 4.2 K coolers are used here. The issues associated with connecting two-stage coolers to liquid absorbers are discussed. The projected heat flows into an absorber and the cool-down of the absorbers using the cooler are presented. The warm-up of the absorber is discussed. Special hydrogen safety issues that may result from the use of a cooler on the absorbers are also discussed.

  12. Surface ionization of terpene hydrocarbons

    SciTech Connect

    Zandberg, E.Y.; Nezdyurov, A.L.; Paleev, V.I.; Ponomarev, D.A.

    1986-09-01

    By means of a surface ionization indicator for traces of materials in the atmosphere it has been established that many natural materials containing terpenes and their derivatives are ionized on the surface of heated molybdenum oxide at atmospheric air pressure. A mass-spectrometer method has been used to explain the mechanism of ionization of individual terpene hydrocarbons and to establish its principles. The ionization of ..cap alpha..-pinene, alloocimene, camphene, and also adamantane on oxidized tungsten under vacuum conditions has been investigated. The ..cap alpha..-pinene and alloocimene are ionized by surface ionization but camphene and adamantane are not ionized under vacuum conditions. The surface ionization mass spectra of ..cap alpha..-pinene and alloocimene are of low line brightness in comparison with electron ionization mass spectra and differ between themselves. The temperature relations for currents of the same compositions of ions during ionization of ..cap alpha..-pinene and alloocimene are also different, which leads to the possibility of surface ionization analysis of mixtures of terpenes being ionized. The ionization coefficients of alloocimene and ..cap alpha..-pinene on oxidized tungsten under temperatures optimum for ionization and the ionization potentials of alloocimene molecules and of radicals (M-H) of both compounds have been evaluated.

  13. Atmospheric Ionization Measurements

    NASA Astrophysics Data System (ADS)

    Slack, Thomas; Mayes, Riley

    2015-04-01

    The measurement of atmospheric ionization is a largely unexplored science that potentially holds the key to better understanding many different geophysical phenomena through this new and valuable source of data. Through the LaACES program, which is funded by NASA through the Louisiana Space Consortium, students at Loyola University New Orleans have pursued the goal of measuring high altitude ionization for nearly three years, and were the first to successfully collect ionization data at altitudes over 30,000 feet using a scientific weather balloon flown from the NASA Columbia Scientific Ballooning Facility in Palestine, TX. In order to measure atmospheric ionization, the science team uses a lightweight and highly customized sensor known as a Gerdien condenser. Among other branches of science the data is already being used for, such as the study of aerosol pollution levels in the atmosphere, the data may also be useful in meteorology and seismology. Ionization data might provide another variable with which to predict weather or seismic activity more accurately and further in advance. Thomas Slack and Riley Mayes have served as project managers for the experiment, and have extensive knowledge of the experiment from the ground up. LaSPACE Louisiana Space Consortium.

  14. Cooling water distribution system

    DOEpatents

    Orr, Richard

    1994-01-01

    A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

  15. Heating and cooling system

    SciTech Connect

    Imig, L.A.; Gardner, M.R.

    1982-08-01

    A heating and cooling apparatus capable of cyclic heating and cooling of a test specimen undergoing fatigue testing is discussed. Cryogenic fluid is passed through a block clamped to the speciment to cool the block and the specimen. Heating cartridges penetrate the block to heat the block and the specimen to very hot temperaures. Control apparatus is provided to alternatively activate the cooling and heating modes to effect cyclic heating and cooling between very hot and very cold temperatures. The block is constructed of minimal mass to facilitate the rapid temperature changes. Official Gazette of the U.S. Patent and Trademark Office.

  16. Construction of the descriptive system for the assessment of quality of life AQoL-6D utility instrument

    PubMed Central

    2012-01-01

    Background Multi attribute utility (MAU) instruments are used to include the health related quality of life (HRQoL) in economic evaluations of health programs. Comparative studies suggest different MAU instruments measure related but different constructs. The objective of this paper is to describe the methods employed to achieve content validity in the descriptive system of the Assessment of Quality of Life (AQoL)-6D, MAU instrument. Methods The AQoL program introduced the use of psychometric methods in the construction of health related MAU instruments. To develop the AQoL-6D we selected 112 items from previous research, focus groups and expert judgment and administered them to 316 members of the public and 302 hospital patients. The search for content validity across a broad spectrum of health states required both formative and reflective modelling. We employed Exploratory Factor Analysis and Structural Equation Modelling (SEM) to meet these dual requirements. Results and Discussion The resulting instrument employs 20 items in a multi-tier descriptive system. Latent dimension variables achieve sensitive descriptions of 6 dimensions which, in turn, combine to form a single latent QoL variable. Diagnostic statistics from the SEM analysis are exceptionally good and confirm the hypothesised structure of the model. Conclusions The AQoL-6D descriptive system has good psychometric properties. They imply that the instrument has achieved construct validity and provides a sensitive description of HRQoL. This means that it may be used with confidence for measuring health related quality of life and that it is a suitable basis for modelling utilities for inclusion in the economic evaluation of health programs. PMID:22507254

  17. The 6dF Galaxy Survey: z≈ 0 measurements of the growth rate and σ8

    NASA Astrophysics Data System (ADS)

    Beutler, Florian; Blake, Chris; Colless, Matthew; Jones, D. Heath; Staveley-Smith, Lister; Poole, Gregory B.; Campbell, Lachlan; Parker, Quentin; Saunders, Will; Watson, Fred

    2012-07-01

    We present a detailed analysis of redshift-space distortions in the two-point correlation function of the 6dF Galaxy Survey (6dFGS). The K-band selected subsample which we employ in this study contains 81 971 galaxies distributed over 17 000 degree2 with an effective redshift zeff= 0.067. By modelling the 2D galaxy correlation function, ?, we measure the parameter combination f(zeff)σ8(zeff) = 0.423 ± 0.055, where ? is the growth rate of cosmic structure and σ8 is the rms of matter fluctuations in 8 h-1 Mpc spheres. Alternatively, by assuming standard gravity we can break the degeneracy between σ8 and the galaxy bias parameter b. Combining our data with the Hubble constant prior from Riess et al., we measure σ8= 0.76 ± 0.11 and Ωm= 0.250 ± 0.022, consistent with constraints from other galaxy surveys and the cosmic microwave background data from Wilkinson Microwave Anisotropy Probe 7 (WMAP7). Combining our measurement of fσ8 with WMAP7 allows us to test the cosmic growth history and the relationship between matter and gravity on cosmic scales by constraining the growth index of density fluctuations, γ. Using only 6dFGS and WMAP7 data we find γ= 0.547 ± 0.088, consistent with the prediction of General Relativity. We note that because of the low effective redshift of the 6dFGS our measurement of the growth rate is independent of the fiducial cosmological model (Alcock-Paczynski effect). We also show that our conclusions are not sensitive to the model adopted for non-linear redshift-space distortions. Using a Fisher matrix analysis we report predictions for constraints on fσ8 for the Wide-field Australian SKA Pathfinder telescope L-band Legacy All-sky Blind surveY (WALLABY) and the proposed Transforming Astronomical Imaging surveys through Polychromatic Analysis of Nebulae (TAIPAN) survey. The WALLABY survey will be able to measure fσ8 with a precision of 4-10 per cent, depending on the modelling of non-linear structure formation. This is comparable to

  18. Induced low-energy effective action in the 6D, N = (1 , 0) hypermultiplet theory on the vector multiplet background

    NASA Astrophysics Data System (ADS)

    Buchbinder, I. L.; Merzlikin, B. S.; Pletnev, N. G.

    2016-08-01

    We consider the six dimensional N = (1 , 0) hypermultiplet model coupled to an external field of the Abelian vector multiplet in harmonic superspace approach. Using the superfield proper-time technique we find the divergent part of the effective action and derive the complete finite induced low-energy superfield effective action. This effective action depends on external field and contains in bosonic sector all the powers of the constant Maxwell field strength. The obtained result can be treated as the 6D, N = (1 , 0) supersymmetric Heisenberg-Euler type effective action.

  19. Metal—Insulator Transition in Bi2Sr2Cu1O6+d (Bi-2201) Thin Films

    NASA Astrophysics Data System (ADS)

    Pop, Aurel V.

    2009-05-01

    We have studied the influence of disorder induced by oxygen on the normal state resistivity of under doped Bi2Sr2Cu1O6+d (Bi-2201) thin films, deposited in situ onto heated SrTiO3 (100) substrates by using DC magnetron sputtering for an off-stoichiometric target. The compositions and structural characterization for the deposited films were carried by (EDX), (XPS) and X-ray diffraction measurements. The effect of partial oxygen pressure in the sputtering gas on the metal-insulator transition are presented.

  20. NASA CF6 jet engine diagnostics program: Long-term CF6-6D low-pressure turbine deterioration

    NASA Technical Reports Server (NTRS)

    Smith, J. J.

    1979-01-01

    Back-to-back performance tests were run on seven airline low pressure turbine (LPT) modules and four new CF6-6D modules. Back-to-back test cell runs, in which an airline LPT module was directly compared to a new production module, were included. The resulting change, measured in fuel burn, equaled the level of LPT module deterioration. Three of the LPT modules were analytically inspected followed by a back-to-back test cell run to evaluate current refurbishment techniques.

  1. Proposal for laser cooling of rare-earth ions

    NASA Astrophysics Data System (ADS)

    Lepers, Maxence; Hong, Ye; Wyart, Jean-François; Dulieu, Olivier

    2016-01-01

    The efficiency of laser cooling relies on the existence of an almost closed optical-transition cycle in the energy spectrum of the considered species. In this respect, rare-earth elements exhibit many transitions which are likely to induce noticeable leaks from the cooling cycle. In this work, to determine whether laser cooling of singly ionized erbium Er+ is feasible, we have performed accurate electronic-structure calculations of energies and spontaneous-emission Einstein coefficients of Er+, using a combination of ab initio and least-squares-fitting techniques. We identify five weak closed transitions suitable for laser cooling, the broadest of which is in the kilohertz range. For the strongest transitions, by simulating the cascade dynamics of spontaneous emission, we show that repumping is necessary, and we discuss possible repumping schemes. We expect our detailed study on Er+ to give good insight into the laser cooling of neighboring ions such as Dy+.

  2. Ambient ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Lebedev, A. T.

    2015-07-01

    Ambient ionization mass spectrometry emerged as a new scientific discipline only about ten years ago. A considerable body of information has been reported since that time. Keeping the sensitivity, performance and informativity of classical mass spectrometry methods, the new approach made it possible to eliminate laborious sample preparation procedures and triggered the development of miniaturized instruments to work directly in the field. The review concerns the theoretical foundations and design of ambient ionization methods. Their advantages and drawbacks, as well as prospects for application in chemistry, biology, medicine, environmetal analysis, etc., are discussed. The bibliography includes 194 references.

  3. Theoretical studies of chromospheres and winds in cool stars

    NASA Technical Reports Server (NTRS)

    Dupree, A. K.

    1981-01-01

    Calculated radiative losses from H, H-, Ca II, and Mg II show that cooling for the chromosphere of the supergiant epsilon Gem do not differ greatly from the solar law, although there are differences at approximately 6000K due to ionization effects. With a rough standard law for computation of stellar winds using the Hartmann-MacGregor theory and standard stellar evolutionary calculations, the wind velocities and temperatures in the HR diagram were systematically explored. Results show that cool winds with tempratures 1,000,00K are not possible for log g or = 2. Predicted wind velocities are approximately 1.5 to 2 x larger than observed, particularly for the most luminous cool stars. The ionization balance for the wind of alpha ORI and the hydrogen profile lines for T Tauri stars were computed using the PANDORA computer program.

  4. Stochastic cooling in RHIC

    SciTech Connect

    Brennan J. M.; Blaskiewicz, M.; Mernick, K.

    2012-05-20

    The full 6-dimensional [x,x'; y,y'; z,z'] stochastic cooling system for RHIC was completed and operational for the FY12 Uranium-Uranium collider run. Cooling enhances the integrated luminosity of the Uranium collisions by a factor of 5, primarily by reducing the transverse emittances but also by cooling in the longitudinal plane to preserve the bunch length. The components have been deployed incrementally over the past several runs, beginning with longitudinal cooling, then cooling in the vertical planes but multiplexed between the Yellow and Blue rings, next cooling both rings simultaneously in vertical (the horizontal plane was cooled by betatron coupling), and now simultaneous horizontal cooling has been commissioned. The system operated between 5 and 9 GHz and with 3 x 10{sup 8} Uranium ions per bunch and produces a cooling half-time of approximately 20 minutes. The ultimate emittance is determined by the balance between cooling and emittance growth from Intra-Beam Scattering. Specific details of the apparatus and mathematical techniques for calculating its performance have been published elsewhere. Here we report on: the method of operation, results with beam, and comparison of results to simulations.

  5. Synthesis of the C-glycoside of α-D-mannose-(1 → 6)-d-myo-inositol†

    PubMed Central

    Hans, Sunej; Altiti, Ahmad; Mootoo, David R.

    2015-01-01

    The dimannosylatedinositol pseudotrisaccharide phospholipid of the lipoarabinomannan (LAM) component of the mycobacterial cell wall has attracted interest as a therapeutic target because of its uniqueness to mycobacteria, its assembly at an early stage in LAM biosynthesis and the immunological activity of oligosaccharides containing this subunit. Accordingly, analogues of this pseudotrisaccharide, α-d-mannose-(1 → 2)-α-d-mannose-(1 → 6)-d-myo-inositol are of interest as mechanistic probes and drug leads. C-glycosides are of special interest because of their hydrolytic stability and conformational differences compared to O-glycosides. Herein, as a prelude to C-glycoside analogues of this pseudotrisaccharide, we describe the synthesis of the C-glycoside of α-D-mannose-(1 → 6)-d-myo-inositol. The synthetic strategy centers on the elaboration of a C1-linked glycal-inositol, the glycone segment of which is assembled via an oxocarbenium ion cyclization on a thioacetal-enol ether precursor that originates from “glycone” and “aglycone” components. PMID:24057020

  6. Alkali ionization detector

    DOEpatents

    Hrizo, John; Bauerle, James E.; Witkowski, Robert E.

    1982-01-01

    A calibration filament containing a sodium-bearing compound is included in combination with the sensing filament and ion collector plate of a sodium ionization detector to permit periodic generation of sodium atoms for the in-situ calibration of the detector.

  7. NASA Microclimate Cooling Challenges

    NASA Technical Reports Server (NTRS)

    Trevino, Luis A.

    2004-01-01

    The purpose of this outline form presentation is to present NASA's challenges in microclimate cooling as related to the spacesuit. An overview of spacesuit flight-rated personal cooling systems is presented, which includes a brief history of cooling systems from Gemini through Space Station missions. The roles of the liquid cooling garment, thermal environment extremes, the sublimator, multi-layer insulation, and helmet visor UV and solar coatings are reviewed. A second section is presented on advanced personal cooling systems studies, which include heat acquisition studies on cooling garments, heat rejection studies on water boiler & radiators, thermal storage studies, and insulation studies. Past and present research and development and challenges are summarized for the advanced studies.

  8. Solar heating and cooling

    NASA Technical Reports Server (NTRS)

    Bartera, R. E.

    1978-01-01

    To emphasize energy conservation and low cost energy, the systems of solar heating and cooling are analyzed and compared with fossil fuel systems. The application of solar heating and cooling systems for industrial and domestic use are discussed. Topics of discussion include: solar collectors; space heating; pools and spas; domestic hot water; industrial heat less than 200 F; space cooling; industrial steam; and initial systems cost. A question and answer period is generated which closes out the discussion.

  9. Ion microscopy based on laser-cooled cesium atoms.

    PubMed

    Viteau, M; Reveillard, M; Kime, L; Rasser, B; Sudraud, P; Bruneau, Y; Khalili, G; Pillet, P; Comparat, D; Guerri, I; Fioretti, A; Ciampini, D; Allegrini, M; Fuso, F

    2016-05-01

    We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam and adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited Rydberg state, then field-ionizing them in an electric field gradient. The method allows obtaining ion currents up to 130pA. Comparison with the standard direct photo-ionization of the atomic beam shows, in our conditions, a 40-times larger ion yield. Preliminary imaging results at ion energies in the 1-5keV range are obtained with a resolution around 40nm, in the present version of the prototype. Our ion beam is expected to be extremely monochromatic, with an energy spread of the order of the eV, offering great prospects for lithography, imaging and surface analysis. PMID:26876642

  10. Modulated voltage metastable ionization detector

    NASA Technical Reports Server (NTRS)

    Carle, G. C.; Kojiro, D. R.; Humphrey, D. E. (Inventor)

    1985-01-01

    The output current from a metastable ionization detector (MID) is applied to a modulation voltage circuit. An adjustment is made to balance out the background current, and an output current, above background, is applied to an input of a strip chart recorder. For low level concentrations, i.e., low detected output current, the ionization potential will be at a maximum and the metastable ionization detector will operate at its most sensitive level. When the detected current from the metastable ionization detector increases above a predetermined threshold level, a voltage control circuit is activated which turns on a high voltage transistor which acts to reduce the ionization potential. The ionization potential applied to the metastable ionization detector is then varied so as to maintain the detected signal level constant. The variation in ionization potential is now related to the concentration of the constituent and a representative amplitude is applied to another input of said strip chart recorder.

  11. Semioptimal practicable algorithmic cooling

    SciTech Connect

    Elias, Yuval; Mor, Tal; Weinstein, Yossi

    2011-04-15

    Algorithmic cooling (AC) of spins applies entropy manipulation algorithms in open spin systems in order to cool spins far beyond Shannon's entropy bound. Algorithmic cooling of nuclear spins was demonstrated experimentally and may contribute to nuclear magnetic resonance spectroscopy. Several cooling algorithms were suggested in recent years, including practicable algorithmic cooling (PAC) and exhaustive AC. Practicable algorithms have simple implementations, yet their level of cooling is far from optimal; exhaustive algorithms, on the other hand, cool much better, and some even reach (asymptotically) an optimal level of cooling, but they are not practicable. We introduce here semioptimal practicable AC (SOPAC), wherein a few cycles (typically two to six) are performed at each recursive level. Two classes of SOPAC algorithms are proposed and analyzed. Both attain cooling levels significantly better than PAC and are much more efficient than the exhaustive algorithms. These algorithms are shown to bridge the gap between PAC and exhaustive AC. In addition, we calculated the number of spins required by SOPAC in order to purify qubits for quantum computation. As few as 12 and 7 spins are required (in an ideal scenario) to yield a mildly pure spin (60% polarized) from initial polarizations of 1% and 10%, respectively. In the latter case, about five more spins are sufficient to produce a highly pure spin (99.99% polarized), which could be relevant for fault-tolerant quantum computing.

  12. High energy electron cooling

    SciTech Connect

    Parkhomchuk, V.

    1997-09-01

    High energy electron cooling requires a very cold electron beam. The questions of using electron cooling with and without a magnetic field are presented for discussion at this workshop. The electron cooling method was suggested by G. Budker in the middle sixties. The original idea of the electron cooling was published in 1966. The design activities for the NAP-M project was started in November 1971 and the first run using a proton beam occurred in September 1973. The first experiment with both electron and proton beams was started in May 1974. In this experiment good result was achieved very close to theoretical prediction for a usual two component plasma heat exchange.

  13. Hydrogen film cooling investigation

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.; Ewen, R. L.

    1973-01-01

    Effects of flow turning, flow acceleration, and supersonic flow on film cooling were determined experimentally and correlated in terms of an entrainment film cooling model. Experiments were conducted using thin walled metal test sections, hot nitrogen mainstream gas, and ambient hydrogen or nitrogen as film coolants. The entrainment film cooling model relates film cooling effectiveness to the amount of mainstream gases entrained with the film coolant in a mixing layer. The experimental apparatus and the analytical model used are described in detail and correlations for the entrainment fraction and film coolant-to-wall heat transfer coefficient are presented.

  14. Power electronics cooling apparatus

    DOEpatents

    Sanger, Philip Albert; Lindberg, Frank A.; Garcen, Walter

    2000-01-01

    A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.

  15. Passive containment cooling system

    DOEpatents

    Conway, Lawrence E.; Stewart, William A.

    1991-01-01

    A containment cooling system utilizes a naturally induced air flow and a gravity flow of water over the containment shell which encloses a reactor core to cool reactor core decay heat in two stages. When core decay heat is greatest, the water and air flow combine to provide adequate evaporative cooling as heat from within the containment is transferred to the water flowing over the same. The water is heated by heat transfer and then evaporated and removed by the air flow. After an initial period of about three to four days when core decay heat is greatest, air flow alone is sufficient to cool the containment.

  16. IONIZATION-DRIVEN FRAGMENTATION OF GAS OUTFLOWS RESPONSIBLE FOR FeLoBALs IN QUASARS

    SciTech Connect

    Bautista, Manuel A.; Dunn, Jay P.

    2010-07-10

    We show that time variations in the UV ionizing continuum of quasars, on scales of {approx}1 yr, affect the dynamic structure of the plasmas responsible for low-ionization broad absorption lines. Variations of the ionizing continuum produce non-equilibrium photoionization conditions over a significant fraction of the absorbing clouds and supersonically moving ionization fronts. When the flux drops, the contraction of the ionized region drives a supersonic cooling front toward the radiation source and a rarefaction wave in the opposite direction. The pressure imbalance is compensated by an increased speed of the cool gas relative to the front. When the flux recovers, the cool gas is re-ionized and re-heated by a supersonic ionization front traveling away from the radiation source and a forward shock is created. The re-heated clouds equilibrate to a temperature of {approx}10{sup 4} K and are observed to have different radial velocities than the main cloud. Such fragmentation seems consistent with the multicomponent structure of troughs seen in some objects. The velocity differences measured among various components in the quasars QSO 2359-1241 and SDSS J0318-0600 can be reproduced by our model if strong magnetic fields ({approx}10 mG) are present within the clouds.

  17. Ionization-driven Fragmentation of Gas Outflows Responsible for FeLoBALs in Quasars

    NASA Astrophysics Data System (ADS)

    Bautista, Manuel A.; Dunn, Jay P.

    2010-07-01

    We show that time variations in the UV ionizing continuum of quasars, on scales of ~1 yr, affect the dynamic structure of the plasmas responsible for low-ionization broad absorption lines. Variations of the ionizing continuum produce non-equilibrium photoionization conditions over a significant fraction of the absorbing clouds and supersonically moving ionization fronts. When the flux drops, the contraction of the ionized region drives a supersonic cooling front toward the radiation source and a rarefaction wave in the opposite direction. The pressure imbalance is compensated by an increased speed of the cool gas relative to the front. When the flux recovers, the cool gas is re-ionized and re-heated by a supersonic ionization front traveling away from the radiation source and a forward shock is created. The re-heated clouds equilibrate to a temperature of ~104 K and are observed to have different radial velocities than the main cloud. Such fragmentation seems consistent with the multicomponent structure of troughs seen in some objects. The velocity differences measured among various components in the quasars QSO 2359-1241 and SDSS J0318-0600 can be reproduced by our model if strong magnetic fields (~10 mG) are present within the clouds.

  18. Electron ionization dynamics of N2 and O2 molecules: Velocity-map imaging

    NASA Astrophysics Data System (ADS)

    Bull, James N.; Lee, Jason W. L.; Vallance, Claire

    2015-02-01

    This paper reports a crossed-beam velocity-map imaging study into the electron ionization dynamics of jet-cooled N2 and O2 molecules at electron collision energies from 35 to 100 eV. The use of velocity-map imaging detection provides insight into the detailed ionization dynamics through the dimension of the product ion kinetic energy associated with impulsive dissociation. In particular, "mesoscopic" cross sections corresponding to ionization from manifolds of energetically close states converging to the same dissociation asymptote are reported for a number of single-ionization channels. In addition, a range of double-ionization cross sections have been characterized, including those yielding X2 2 + dications. These are found to be in excellent agreement with other cross sections determined in coincidence measurements. This agreement supports a meaningful and accurate determination of the single-ionization channels.

  19. E6D25E, HPV16 Asian variant shows specific proteomic pattern correlating in cells transformation and suppressive innate immune response.

    PubMed

    Chopjitt, Peechanika; Pientong, Chamsai; Sunthamala, Nuchsupha; Kongyingyoes, Bunkerd; Haonon, Ornuma; Boonmars, Thidarut; Kikawa, Satomi; Nakahara, Tomomi; Kiyono, Tohru; Ekalaksananan, Tipaya

    2016-09-01

    HPV16 Asian variant (HPV16As) containing E6D25E oncogene, is commonly associated with cervical cancers of Asian populations. To explore a mechanism of E6D25E oncoprotein in carcinogenesis, we compared protein profiles in human keratinocytes expressing E6D25E with E6 of HPV16 prototype (E6Pro). A human cervical keratinocyte cell line, HCK1T, was transduced with retroviruses containing E6D25E or E6Pro genes. Biological properties of E6D25E or E6Pro transduced HCK1T cells were characterized. Protein profiles of the transduced HCK1T cells were analyzed using 2D-PAGE and characterized by mass spectrometry and western blotting. Reactomes of modulated proteins were analyzed by using the Reactome Knowledgebase. The E6D25E and E6Pro oncoproteins were comparable for their abilities to degrade p53 and suppress the induction of p21, and induce cell proliferation. Interestingly, the protein profiles of the HCK1T cells transduced with E6D25E showed specific proteomic patterns different from those with E6Pro. Among altered proteins, more than 1.5-fold up- or down- regulation was observed in E6D25E-expressing cells for gp96 and keratin7 which involved in activation of TLR signaling and transformation of squamocolumnar junction cells, respectively. This report describes new cellular proteins specifically targeted by E6D25E oncoprotein that may contribute to impair immune response against viral infection and cell transformation associated with oncogenic property of HPV16As variant. PMID:27392712

  20. Ultrahigh vacuum measuring ionization gauge

    NASA Technical Reports Server (NTRS)

    Brock, F. J. (Inventor)

    1968-01-01

    The ionization gage described consists of separate ionization and collector regions connected at an exit area with a modulator electrode. In addition to the standard modulation function, the modulator in this location yields a suprising increase in collector current, apparently due to improved focussing and extraction of ions from the ionization region.

  1. Lithium lenses based muon cooling channel

    SciTech Connect

    Valeri I. Balbekov

    2003-05-28

    A linear ionization cooling channel for neutrino factory or muon collider is considered. It includes short Li lenses, matching solenoids, and 201 MHz RF cavities. The basic challenge is a suppression of chromatic effects in a wide energy range typical for muon beams. A special lattice is proposed to reach this, and methodic of an optimization is developed to minimize the chromatic aberrations by suppression of several betatron resonances. The most engineering constraint is a high field of matching solenoids. A channel with less of 10 T field is considered in detail. It is capable to cool transverse emittance of a beam from 2-3 mm to 0.5 mm at the channel length of about 130 m. Because there is no emittance exchange, longitudinal emittance increases in the process from 10 to 20 mm at transmission of about 90%.

  2. Stacking with stochastic cooling

    NASA Astrophysics Data System (ADS)

    Caspers, Fritz; Möhl, Dieter

    2004-10-01

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105 the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some considerations to the 'azimuthal' schemes.

  3. Liquid metal cooled nuclear reactors with passive cooling system

    DOEpatents

    Hunsbedt, Anstein; Fanning, Alan W.

    1991-01-01

    A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of cooling medium flow circuits which cooperate to remove and carry heat away from the fuel core upon loss of the normal cooling flow circuit to areas external thereto.

  4. DOAS, Radiant Cooling Revisited

    SciTech Connect

    Hastbacka, Mildred; Dieckmann, John; Bouza, Antonio

    2012-12-01

    The article discusses dedicated outdoor air systems (DOAS) and radiant cooling technologies. Both of these topics were covered in previous ASHRAE Journal columns. This article reviews the technologies and their increasing acceptance. The two steps that ASHRAE is taking to disseminate DOAS information to the design community, available energy savings and the market potential of radiant cooling systems are addressed as well.

  5. Measure Guideline: Ventilation Cooling

    SciTech Connect

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline on ventilation cooling is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  6. Why Cool Roofs?

    ScienceCinema

    Chu, Steven

    2013-05-29

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  7. Cool Earth Solar

    ScienceCinema

    Lamkin, Rob; McIlroy, Andy; Swalwell, Eric; Rajan, Kish

    2014-02-26

    In a public-private partnership that takes full advantage of the Livermore Valley Open Campus (LVOC) for the first time, Sandia National Laboratories and Cool Earth Solar have signed an agreement that could make solar energy more affordable and accessible. In this piece, representatives from Sandia, Cool Earth Solar, and leaders in California government all discuss the unique partnership and its expected impact.

  8. Data center cooling method

    DOEpatents

    Chainer, Timothy J.; Dang, Hien P.; Parida, Pritish R.; Schultz, Mark D.; Sharma, Arun

    2015-08-11

    A method aspect for removing heat from a data center may use liquid coolant cooled without vapor compression refrigeration on a liquid cooled information technology equipment rack. The method may also include regulating liquid coolant flow to the data center through a range of liquid coolant flow values with a controller-apparatus based upon information technology equipment temperature threshold of the data center.

  9. Coherent electron cooling

    SciTech Connect

    Litvinenko,V.

    2009-05-04

    Cooling intense high-energy hadron beams remains a major challenge in modern accelerator physics. Synchrotron radiation is still too feeble, while the efficiency of two other cooling methods, stochastic and electron, falls rapidly either at high bunch intensities (i.e. stochastic of protons) or at high energies (e-cooling). In this talk a specific scheme of a unique cooling technique, Coherent Electron Cooling, will be discussed. The idea of coherent electron cooling using electron beam instabilities was suggested by Derbenev in the early 1980s, but the scheme presented in this talk, with cooling times under an hour for 7 TeV protons in the LHC, would be possible only with present-day accelerator technology. This talk will discuss the principles and the main limitations of the Coherent Electron Cooling process. The talk will describe the main system components, based on a high-gain free electron laser driven by an energy recovery linac, and will present some numerical examples for ions and protons in RHIC and the LHC and for electron-hadron options for these colliders. BNL plans a demonstration of the idea in the near future.

  10. District cooling in Scandinavia

    SciTech Connect

    Andersson, B.

    1996-11-01

    This paper will present the status of the development of district cooling systems in Scandinavia over the last 5 years. It will describe the technologies used in the systems that have been constructed as well as the options considered in different locations. It will identify the drivers for the development of the cooling business to-date, and what future drivers for a continuing development of district cooling in Sweden. To-date, approximately 25 different cities of varying sizes have completed feasibility studies to determine if district cooling is an attractive option. In a survey, that was conducted by the Swedish District Heating Association, some 25 cities expected to have district cooling systems in place by the year 2000. In Sweden, district heating systems with hot water is very common. In many cases, it is simply an addition to the current service for the district heating company to also supply district cooling to the building owners. A parallel from this can be drawn to North America where district cooling systems now are developing rapidly. I am convinced that in these cities a district heating service will be added as a natural expansion of the district cooling company`s service.

  11. Liquid Cooled Garments

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Astronauts working on the surface of the moon had to wear liquid-cooled garments under their space suits as protection from lunar temperatures which sometimes reach 250 degrees Fahrenheit. In community service projects conducted by NASA's Ames Research Center, the technology developed for astronaut needs has been adapted to portable cooling systems which will permit two youngsters to lead more normal lives.

  12. Why Cool Roofs?

    SciTech Connect

    Chu, Steven

    2010-01-01

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  13. S'COOL Science

    ERIC Educational Resources Information Center

    Bryson, Linda

    2004-01-01

    This article describes one fifth grade's participation in in NASA's S'COOL (Students' Cloud Observations On-Line) Project, making cloud observations, reporting them online, exploring weather concepts, and gleaning some of the things involved in authentic scientific research. S?COOL is part of a real scientific study of the effect of clouds on…

  14. Gridded electron reversal ionizer

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor)

    1993-01-01

    A gridded electron reversal ionizer forms a three dimensional cloud of zero or near-zero energy electrons in a cavity within a filament structure surrounding a central electrode having holes through which the sample gas, at reduced pressure, enters an elongated reversal volume. The resultant negative ion stream is applied to a mass analyzer. The reduced electron and ion space-charge limitations of this configuration enhances detection sensitivity for material to be detected by electron attachment, such as narcotic and explosive vapors. Positive ions may be generated by generating electrons having a higher energy, sufficient to ionize the target gas and pulsing the grid negative to stop the electron flow and pulsing the extraction aperture positive to draw out the positive ions.

  15. Turbine blade cooling using Coulomb repulsion

    NASA Astrophysics Data System (ADS)

    Breidenthal, Robert; Colannino, Joseph; Dees, John; Goodson, David; Krichtafovitch, Igor; Prevo, Tracy

    2012-11-01

    Video photography and thermocouples reveal the effect of an electric field on the flow around a stationary, idealized turbine blade downstream of a combustor. The hot products of combustion naturally include positive ions. When the blade is an electrode and elevated to a positive potential, it tends to attract the free electrons and repel the positive ions. Due to their lower mass, the light electrons are rapidly swept toward the blade, while the positive ions are repelled. As they collide with the neutrals in the hot gas, the positive ions transfer their momentum so that a Coulomb body force is exerted on the hot gas. Cool, compressed air is injected out of the stationary blade near its leading edge to form a layer of film cooling. In contrast to the hot combustion products, the cool air is not ionized. At the interface between the hot gas and the cool air, the Coulomb repulsion force acts on the former but not the latter, analogous to gravity at a stratified interface. An effective Richardson number representing the ratio of potential to kinetic energy characterizes the topography of the interface. When the electric field is turned on, the repulsion of the hot gas from the idealized blade is evident in video recordings and thermocouple measurements.

  16. Electrospray Ionization Mass Spectrometry

    SciTech Connect

    Kelly, Ryan T.; Marginean, Ioan; Tang, Keqi

    2014-06-13

    Electrospray Ionization (ESI) is a process whereby gas phase ions are created from molecules in solution. As a solution exits a narrow tube in the presence of a strong electric field, an aerosol of charged droplets are is formed that produces gas phase ions as they it desolvates. ESI-MS comprises the creation of ions by ESI and the determination of their mass to charge ratio (m/z) by MS.

  17. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf; Willett, Fred Thomas

    1999-07-20

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

  18. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf; Willett, Fred Thomas

    2000-01-01

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

  19. Hydronic rooftop cooling systems

    DOEpatents

    Bourne, Richard C.; Lee, Brian Eric; Berman, Mark J.

    2008-01-29

    A roof top cooling unit has an evaporative cooling section that includes at least one evaporative module that pre-cools ventilation air and water; a condenser; a water reservoir and pump that captures and re-circulates water within the evaporative modules; a fan that exhausts air from the building and the evaporative modules and systems that refill and drain the water reservoir. The cooling unit also has a refrigerant section that includes a compressor, an expansion device, evaporator and condenser heat exchangers, and connecting refrigerant piping. Supply air components include a blower, an air filter, a cooling and/or heating coil to condition air for supply to the building, and optional dampers that, in designs that supply less than 100% outdoor air to the building, control the mixture of return and ventilation air.

  20. Water cooled steam jet

    DOEpatents

    Wagner, Jr., Edward P.

    1999-01-01

    A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed therebetween. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock.

  1. Turbine blade cooling

    SciTech Connect

    Staub, F.W.; Willett, F.T.

    1999-07-20

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number. 13 figs.

  2. Water cooled steam jet

    DOEpatents

    Wagner, E.P. Jr.

    1999-01-12

    A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed there between. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock. 2 figs.

  3. HEATING AND COOLING PROTOSTELLAR DISKS

    SciTech Connect

    Hirose, S.; Turner, N. J. E-mail: neal.turner@jpl.nasa.gov

    2011-05-10

    We examine heating and cooling in protostellar disks using three-dimensional radiation-MHD calculations of a patch of the Solar nebula at 1 AU, employing the shearing-box and flux-limited radiation diffusion approximations. The disk atmosphere is ionized by stellar X-rays, well coupled to magnetic fields, and sustains a turbulent accretion flow driven by magnetorotational instability, while the interior is resistive and magnetically dead. The turbulent layers are heated by absorbing the light from the central star and by dissipating the magnetic fields. They are optically thin to their own radiation and cool inefficiently. The optically thick interior in contrast is heated only weakly, by re-emission from the atmosphere. The interior is colder than a classical viscous model and isothermal. The magnetic fields support an extended atmosphere that absorbs the starlight 1.5 times higher than the hydrostatic viscous model. The disk thickness thus measures not the internal temperature, but the magnetic field strength. Fluctuations in the fields move the starlight-absorbing surface up and down. The height ranges between 13% and 24% of the radius over timescales of several orbits, with implications for infrared variability. The fields are buoyant, so the accretion heating occurs higher in the atmosphere than the stresses. The heating is localized around current sheets, caused by magnetorotational instability at lower elevations and by Parker instability at higher elevations. Gas in the sheets is heated above the stellar irradiation temperature, even though accretion is much less than irradiation power when volume averaged. The hot optically thin current sheets might be detectable through their line emission.

  4. The impact of pneumococcal conjugate vaccines on carriage of and disease caused by Streptococcus pneumoniae serotypes 6C and 6D in southern Israel.

    PubMed

    Porat, Nurith; Benisty, Rachel; Givon-Lavi, Noga; Trefler, Ronit; Dagan, Ron

    2016-05-27

    The introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) followed by PCV13 resulted in a dramatic reduction in carriage and disease rates of Streptococcus pneumoniae (Sp) serotype 6B (Sp6B) and Sp6A. The structural modifications of the capsule of Sp6A and Sp6B to become Sp6C and Sp6D, respectively, raised a concern that eradication of Sp6A/Sp6B by PCV could be accompanied by an increase in Sp6C/Sp6D. This study examines the dynamics and clonal distribution of Sp6C/Sp6D relative to Sp6A/Sp6B during 1999-2014, pre- and post-PCV implementation. Sp were cultured from Blood/CSF and MEF of children <2 years, and from conjunctiva and nasopharynx of children <5 years. PCR was applied for Sp6C and Sp6D identification. Clonality was determined by PFGE and MLST. PCV introduction resulted in decreased carriage rates and conjunctivitis caused by serogroup 6 serotypes. Incidence of Sp6A, Sp6B and Sp6D in otitis media dropped gradually along with PCV7/13 introduction, whereas Sp6C rates increased in the PCV7 period and then decreased following PCV13 implementation. In invasive pneumococcal disease, complete elimination of serogroup 6 was found in the PCV era. Similar clonal composition was found for Sp6C and Sp6D pre- and post-PCV. We conclude that Sp6C and Sp6D do not act as replacement serotypes for Sp6A and Sp6B following vaccination with PCV13. The major Sp6C and Sp6D clones present pre-PCV persisted also post-PCV implementation, suggesting that these clones possess an advantage retained post-vaccination. PMID:27113163

  5. MEIC electron cooling program

    SciTech Connect

    Derbenev, Yaroslav S.; Zhang, Yuhong

    2014-12-01

    Cooling of proton and ion beams is essential for achieving high luminosities (up to above 1034 cm-2s-1) for MEIC, a Medium energy Electron-Ion Collider envisioned at JLab [1] for advanced nuclear science research. In the present conceptual design, we utilize the conventional election cooling method and adopted a multi-staged cooling scheme for reduction of and maintaining low beam emittances [2,3,4]. Two electron cooling facilities are required to support the scheme: one is a low energy (up to 2 MeV) DC cooler installed in the MEIC ion pre-booster (with the proton kinetic energy up to 3 GeV); the other is a high electron energy (up to 55 MeV) cooler in the collider ring (with the proton kinetic energy from 25 to 100 GeV). The high energy cooler, which is based on the ERL technology and a circulator ring, utilizes a bunched electron beam to cool bunched proton or ion beams. To complete the MEIC cooling concept and a technical design of the ERL cooler as well as to develop supporting technologies, an R&D program has been initiated at Jefferson Lab and significant progresses have been made since then. In this study, we present a brief description of the cooler design and a summary of the progress in this cooling R&D.

  6. MEIC electron cooling program

    DOE PAGESBeta

    Derbenev, Yaroslav S.; Zhang, Yuhong

    2014-12-01

    Cooling of proton and ion beams is essential for achieving high luminosities (up to above 1034 cm-2s-1) for MEIC, a Medium energy Electron-Ion Collider envisioned at JLab [1] for advanced nuclear science research. In the present conceptual design, we utilize the conventional election cooling method and adopted a multi-staged cooling scheme for reduction of and maintaining low beam emittances [2,3,4]. Two electron cooling facilities are required to support the scheme: one is a low energy (up to 2 MeV) DC cooler installed in the MEIC ion pre-booster (with the proton kinetic energy up to 3 GeV); the other is amore » high electron energy (up to 55 MeV) cooler in the collider ring (with the proton kinetic energy from 25 to 100 GeV). The high energy cooler, which is based on the ERL technology and a circulator ring, utilizes a bunched electron beam to cool bunched proton or ion beams. To complete the MEIC cooling concept and a technical design of the ERL cooler as well as to develop supporting technologies, an R&D program has been initiated at Jefferson Lab and significant progresses have been made since then. In this study, we present a brief description of the cooler design and a summary of the progress in this cooling R&D.« less

  7. Towards Laser Cooling Trapped Ions with Telecom Light

    NASA Astrophysics Data System (ADS)

    Dungan, Kristina; Becker, Patrick; Donoghue, Liz; Liu, Jackie; Olmschenk, Steven

    2015-05-01

    Quantum information has many potential applications in communication, atomic clocks, and the precision measurement of fundamental constants. Trapped ions are excellent candidates for applications in quantum information because of their isolation from external perturbations, and the precise control afforded by laser cooling and manipulation of the quantum state. For many applications in quantum communication, it would be advantageous to interface ions with telecom light. We present progress towards laser cooling and trapping of doubly-ionized lanthanum, which should require only infrared, telecom-compatible light. Additionally, we present progress on optimization of a second-harmonic generation cavity for laser cooling and trapping barium ions, for future sympathetic cooling experiments. This research is supported by the Army Research Office, Research Corporation for Science Advancement, and Denison University.

  8. Optimization of evaporative cooling

    NASA Astrophysics Data System (ADS)

    Sackett, C. A.; Bradley, C. C.; Hulet, R. G.

    1997-05-01

    Recent experiments have used forced evaporative cooling to produce Bose-Einstein condensation in dilute gases. The evaporative cooling process can be optimized to provide the maximum phase-space density with a specified number of atoms remaining. We show that this global optimization is approximately achieved by locally optimizing the cooling efficiency at each instant. We discuss how this method can be implemented, and present the results for our 7Li trap. The predicted behavior of the gas is found to agree well with experiment.

  9. Personal Cooling System

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Cool Head, a personal cooling system for use in heat stress occupations, is a spinoff of a channeled cooling garment for space wear. It is portable and includes a heat exchanger, control display unit, liquid reservoir and temperature control unit. The user can eliminate 40 to 60 percent of his body's heat storage and lower heart rate by 50 to 80 beats a minute. The system is used by the Army, Navy, crop dusting pilots, heavy equipment operators and auto racing drivers and is marketed by Life Enhancement Technologies, LLC. Further applications are under consideration.

  10. Feedback cooling of currents

    NASA Astrophysics Data System (ADS)

    Washburn, Sean

    1989-02-01

    Just as feedback can be used to correct errors in the output voltages of amplifiers, it can also be used to remove noise from the current through a resistor. Such a feedback amplifier behaves as a refrigerator cooling the electrons in a resistor connnected to it. This principle has been recognized since the 1940s but has been largely ignored because the cooling power available from such refrigerators is miniscule. It is pointed out here that the method might be practical for cooling the currents in the microscopic circuits that are typical of modern electrical engineering and recent studies in transport physics.

  11. Dosimetric effects of positioning shifts using 6D-frameless stereotactic Brainlab system in hypofractionated intracranial radiotherapy.

    PubMed

    Jin, Hosang; Keeling, Vance P; Ali, Imad; Ahmad, Salahuddin

    2016-01-01

    Dosimetric consequences of positional shifts were studied using frameless Brainlab ExacTrac X-ray system for hypofractionated (3 or 5 fractions) intracranial stereo-tactic radiotherapy (SRT). SRT treatments of 17 patients with metastatic intracranial tumors using the stereotactic system were retrospectively investigated. The treatments were simulated in a treatment planning system by modifying planning parameters with a matrix conversion technique based on positional shifts for initial infrared (IR)-based setup (XC: X-ray correction) and post-correction (XV: X-ray verification). The simulation was implemented with (a) 3D translational shifts only and (b) 6D translational and rotational shifts for dosimetric effects of angular correction. Mean translations and rotations (± 1 SD) of 77 fractions based on the initial IR setup (XC) were 0.51 ± 0.86 mm (lateral), 0.30 ± 1.55 mm (longitudinal), and -1.63 ± 1.00 mm (vertical); -0.53° ± 0.56° (pitch), 0.42° ± 0.60° (roll), and 0.44°± 0.90° (yaw), respectively. These were -0.07 ± 0.24 mm, -0.07 ± 0.25 mm, 0.06± 0.21 mm, 0.04° ± 0.23°, 0.00° ± 0.30°, and -0.02° ± 0.22°, respectively, for the postcorrection (XV). Substantial degradation of the treatment plans was observed in D95 of PTV (2.6% ± 3.3%; simulated treatment versus treatment planning), Dmin of PTV (13.4% ± 11.6%), and Dmin of CTV (2.8% ± 3.8%, with the maximum error of 10.0%) from XC, while dosimetrically negligible changes (< 0.1%) were detected for both CTV and PTV from XV simulation. 3D angular correction significantly improved CTV dose coverage when the total angular shifts (|pitch| + |roll| + |yaw|) were greater than 2°. With the 6D stereoscopic X-ray verification imaging and frameless immobilization, submillimeter and subdegree accuracy is achieved with negligible dosimetric deviations. 3D angular correction is required when the angular deviation is substantial. A CTV-to-PTV safety margin of 2 mm is large enough to prevent

  12. Stimulated radiative laser cooling

    NASA Astrophysics Data System (ADS)

    Muys, P.

    2008-04-01

    Building a refrigerator based on the conversion of heat into optical energy is an ongoing engineering challenge. Under well-defined conditions, spontaneous anti-Stokes fluorescence of a dopant material in a host matrix is capable of lowering the host temperature. The fluorescence is conveying away a part of the thermal energy stored in the vibrational oscillations of the host lattice. In particular, applying this principle to the cooling of (solid-state) lasers opens up many potential device applications, especially in the domain of high-power lasers. In this paper, an alternative optical cooling scheme is outlined, leading to the radiative cooling of solid-state lasers. It is based on converting the thermal energy stored in the host into optical energy by means of a stimulated nonlinear process, rather than a spontaneous process. This should lead to better cooling efficiencies and a higher potential of applying the principle for device applications.

  13. Sisyphus cooling of lithium

    NASA Astrophysics Data System (ADS)

    Hamilton, Paul; Kim, Geena; Joshi, Trinity; Mukherjee, Biswaroop; Tiarks, Daniel; Müller, Holger

    2014-02-01

    Laser cooling to sub-Doppler temperatures by optical molasses is thought to be inhibited in atoms with unresolved, near-degenerate hyperfine structure in the excited state. We demonstrate that such cooling is possible in one to three dimensions, not only near the standard D2 line for laser cooling, but over a wide range extending to the D1 line. Via a combination of Sisyphus cooling followed by adiabatic expansion, we reach temperatures as low as 40 μK, which corresponds to atomic velocities a factor of 2.6 above the limit imposed by a single-photon recoil. Our method requires modest laser power at a frequency within reach of standard frequency-locking methods. It is largely insensitive to laser power, polarization and detuning, magnetic fields, and initial hyperfine populations. Our results suggest that optical molasses should be possible with all alkali-metal species.

  14. Why Exercise Is Cool

    MedlinePlus

    ... Homework? Here's Help White House Lunch Recipes Why Exercise Is Cool KidsHealth > For Kids > Why Exercise Is ... day and your body will thank you later! Exercise Makes Your Heart Happy You may know that ...

  15. Too cool to work

    NASA Astrophysics Data System (ADS)

    Moya, Xavier; Defay, Emmanuel; Heine, Volker; Mathur, Neil D.

    2015-03-01

    Magnetocaloric and electrocaloric effects are driven by doing work, but this work has barely been explored, even though these caloric effects are being exploited in a growing number of prototype cooling devices.

  16. Warm and Cool Dinosaurs.

    ERIC Educational Resources Information Center

    Mannlein, Sally

    2001-01-01

    Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of warm and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)

  17. Waveguide cooling system

    NASA Technical Reports Server (NTRS)

    Chen, B. C. J.; Hartop, R. W. (Inventor)

    1981-01-01

    An improved system is described for cooling high power waveguides by the use of cooling ducts extending along the waveguide, which minimizes hot spots at the flanges where waveguide sections are connected together. The cooling duct extends along substantially the full length of the waveguide section, and each flange at the end of the section has a through hole with an inner end connected to the duct and an opposite end that can be aligned with a flange hole in another waveguide section. Earth flange is formed with a drainage groove in its face, between the through hole and the waveguide conduit to prevent leakage of cooling fluid into the waveguide. The ducts have narrowed sections immediately adjacent to the flanges to provide room for the installation of fasteners closely around the waveguide channel.

  18. Evaporative Cooling Membrane Device

    NASA Technical Reports Server (NTRS)

    Lomax, Curtis (Inventor); Moskito, John (Inventor)

    1999-01-01

    An evaporative cooling membrane device is disclosed having a flat or pleated plate housing with an enclosed bottom and an exposed top that is covered with at least one sheet of hydrophobic porous material having a thin thickness so as to serve as a membrane. The hydrophobic porous material has pores with predetermined dimensions so as to resist any fluid in its liquid state from passing therethrough but to allow passage of the fluid in its vapor state, thereby, causing the evaporation of the fluid and the cooling of the remaining fluid. The fluid has a predetermined flow rate. The evaporative cooling membrane device has a channel which is sized in cooperation with the predetermined flow rate of the fluid so as to produce laminar flow therein. The evaporative cooling membrane device provides for the convenient control of the evaporation rates of the circulating fluid by adjusting the flow rates of the laminar flowing fluid.

  19. WATER COOLED RETORT COVER

    DOEpatents

    Ash, W.J.; Pozzi, J.F.

    1962-05-01

    A retort cover is designed for use in the production of magnesium metal by the condensation of vaporized metal on a collecting surface. The cover includes a condensing surface, insulating means adjacent to the condensing surface, ind a water-cooled means for the insulating means. The irrangement of insulation and the cooling means permits the magnesium to be condensed at a high temperature and in massive nonpyrophoric form. (AEC)

  20. Liquid cooled helmet

    NASA Technical Reports Server (NTRS)

    Elkins, William (Inventor); Williams, Bill A. (Inventor)

    1979-01-01

    Liquid cooled helmet comprising a cap of flexible material adapted to fit the head of a person, cooling panels mounted inside the cap forming passageways for carrying a liquid coolant, the panels being positioned to engage the cranium and neck of a person wearing the helmet, inlet and outlet lines communicating with the passageways, and releasable straps for securing the helmet about the neck of the wearer.

  1. Laser cooling of solids

    SciTech Connect

    Epstein, Richard I; Sheik-bahae, Mansoor

    2008-01-01

    We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

  2. Refrigerant directly cooled capacitors

    DOEpatents

    Hsu, John S.; Seiber, Larry E.; Marlino, Laura D.; Ayers, Curtis W.

    2007-09-11

    The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

  3. Ionization of polarized hydrogen atoms

    SciTech Connect

    Alessi, J.G.

    1983-01-01

    Methods are discussed for the production of polarized H/sup -/ ions from polarized atoms produced in ground state atomic beam sources. Present day sources use ionizers of two basic types - electron ionizers for H/sup +/ Vector production followed by double charge exchange in a vapor, or direct H/sup -/ Vector production by charge exchange of H/sup 0/ with Cs/sup 0/. Both methods have ionization efficiencies of less than 0.5%. Ionization efficiencies in excess of 10% may be obtained in the future by the use of a plasma ionizer plus charge exchange in Cs or Sr vapor, or ionization by resonant charge exchange with a self-extracted D/sup -/ beam from a ring magnetron or HCD source. 36 references, 4 figures.

  4. Plasma Production via Field Ionization

    SciTech Connect

    O'Connell, C.L.; Barnes, C.D.; Decker, F.; Hogan, M.J.; Iverson, R.; Krejcik, P.; Siemann, R.; Walz, D.R.; Clayton, C.E.; Huang, C.; Johnson, D.K.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.; Zhou, M.; Deng, S.; Katsouleas, T.; Muggli, P.; Oz, E.; /Southern California U.

    2007-01-02

    Plasma production via field ionization occurs when an incoming particle beam is sufficiently dense that the electric field associated with the beam ionizes a neutral vapor or gas. Experiments conducted at the Stanford Linear Accelerator Center explore the threshold conditions necessary to induce field ionization by an electron beam in a neutral lithium vapor. By independently varying the transverse beam size, number of electrons per bunch or bunch length, the radial component of the electric field is controlled to be above or below the threshold for field ionization. Additional experiments ionized neutral xenon and neutral nitric oxide by varying the incoming beam's bunch length. A self-ionized plasma is an essential step for the viability of plasma-based accelerators for future high-energy experiments.

  5. Using the SF-6D to measure the impact of alcohol dependence on health-related quality of life.

    PubMed

    Nogueira, Jacinto Mosquera; Rodríguez-Míguez, Eva

    2015-05-01

    Alcohol dependence not only reduces life expectancy, but also causes considerable loss of quality of life of the dependents of and persons around those with alcohol dependence. This article presents new evidence on the impact of alcohol dependence on health-related quality of life in Spain. Three samples were recruited: 150 alcoholics and 64 family members of alcoholics, with both samples taken from an alcoholism treatment unit, and 600 persons from the general population. We used the short form 6D, a preference-based generic instrument, applying the utility scores estimated for Spain. It was found that the annual mean loss of quality-adjusted life years associated with alcohol dependence was 0.144 and 0.083 for the alcoholics and their close family members, respectively. This impact becomes more notable after controlling for socio economic variables and was higher than that estimated in similar studies. Possible explanations for these differences are discussed. The results from this work can be applied to economic evaluation studies measuring benefits from policies targeted at reducing the prevalence of alcohol dependence. PMID:25193526

  6. Calculations of the first- and second-correction-to-scaling amplitudes to order 6-d in the percolation problem

    NASA Astrophysics Data System (ADS)

    Chang, Mau-Chung

    1985-07-01

    The correction to scaling in the bond percolation problem near the percolation threshold is studied. One can write & [1+a+/-i||t||ων+b+/-i||t|| 2ων+O(||t||3ων)], where t=(pc-p)/pc, p is the percolation concentration, + (-) stands for ppc), and a+/-i,b+/-i are the first- and second-correction-to-scaling amplitudes, respectively; fi(t) can be the probability of a site being in the infinite cluster, the clusters' mean-square size, the mean number of clusters, or the pair-connected correlation length. It is shown that a+/-i/a+/-j, b+/-i/b+/-j, and b+/-i/a+/-2j are universal quantities. The detailed calculations are carried out to order ɛ (ɛ=6-d) using the two-loop renormalization results by Amit adopting the minimal subtraction procedures. The results for a+/-i/a+/-j to the zeroth order in ɛ are in agreement with those of Aharony using the recursion-relation approach. Some implications due to the second-correction-to-scaling term in the theory of critical phenomena are discussed.

  7. SU(2) deformations of the minimal unitary representation of OSp(8*|2N) as massless 6D conformal supermultiplets

    NASA Astrophysics Data System (ADS)

    Fernando, Sudarshan; Günaydin, Murat

    2011-02-01

    Minimal unitary representation of SO(8)≃SO(6,2) realized over the Hilbert space of functions of five variables and its deformations labeled by the spin t of an SU(2) subgroup correspond to massless conformal fields in six dimensions as was shown in [S. Fernando, M. Gunaydin, arXiv:1005.3580]. In this paper we study the minimal unitary supermultiplet of OSp(8|2N) with the even subgroup SO(8)×USp(2N) and its deformations using quasiconformal methods. We show that the minimal unitary supermultiplet of OSp(8|2N) admits deformations labeled uniquely by the spin t of an SU(2) subgroup of the little group SO(4) of lightlike vectors in six dimensions. We construct the deformed minimal unitary representations and show that they correspond to massless 6 D conformal supermultiplets. The minimal unitary supermultiplet of OSp(8|4) is the massless supermultiplet of (2,0) conformal field theory that is believed to be dual to M-theory on AdS×S. We study its deformations in further detail and show that they are isomorphic to the doubleton supermultiplets constructed by using twistorial oscillators.

  8. Lifetime of the 7s6d {sup 1}D{sub 2} atomic state of radium.

    SciTech Connect

    Trimble, W. L.; Sulai, I. A.; Ahmad, I.; Bailey, K.; Graner, B.; Greene, J. P.; Holt, R. J.; Korsch, W.; Lu, Z.-T.; Mueller, P.; O'Connor, T. P.; Physics; Univ. of Chicago; Univ. of Kentucky

    2009-01-01

    The lifetime of the 7s6d {sup 1}D{sub 2} state of atomic radium is determined to be 385(45) {mu}s using cold {sup 226}Ra atoms prepared in a magneto-optical trap. The {sup 1}D{sub 2} state is populated from the decay of the {sup 1}P{sub 1} state which is excited by a pulse of 483 nm light. The decay of the {sup 1}D{sub 2} state is observed by detecting delayed fluorescence at 714 nm from the last step in the decay sequence {sup 1}P{sub 1}-{sup 1}D{sub 2}-{sup 3}P{sub 1}-{sup 1}S{sub 0}. The measured lifetime is compared to a number of theoretical calculations. An improved value of the 7s7p {sup 1}P{sub 1} level of 20 715.598(6) cm{sup -1} is obtained.

  9. Charge recombination in the muon collider cooling channel

    SciTech Connect

    Fernow, R. C.; Palmer, R. B.

    2012-12-21

    The final stage of the ionization cooling channel for the muon collider must transversely recombine the positively and negatively charged bunches into a single beam before the muons can be accelerated. It is particularly important to minimize any emittance growth in this system since no further cooling takes place before the bunches are collided. We have found that emittance growth could be minimized by using symmetric pairs of bent solenoids and careful matching. We show that a practical design can be found that has transmission {approx}99%, emittance growth less than 0.1%, and minimal dispersion in the recombined bunches.

  10. The MuCool Test Area and RF Program

    SciTech Connect

    Bross, A D; Jansson, A; Moretti, A; Yonehara, K; Huang, D; Torun, Y; Li, D; Norem, J; Palmer, R B; Stratakis, D

    2010-05-01

    The MuCool RF Program focuses on the study of normal conducting RF structures operating in high magnetic field for applications in muon ionization cooling for Neutrino Factories and Muon Colliders. This paper will give an overview of the program, which will include a description of the test facility and its capabilities, the current test program, and the status of a cavity that can be rotated in the magnetic field which allows for a more detailed study of the maximum stable operating gradient vs. magnetic field strength and angle.

  11. Estimating the burden of disease in chronic pain with and without neuropathic characteristics: does the choice between the EQ-5D and SF-6D matter?

    PubMed

    Torrance, Nicola; Lawson, Kenny D; Afolabi, Ebenezer; Bennett, Michael I; Serpell, Michael G; Dunn, Kate M; Smith, Blair H

    2014-10-01

    The EQ-5D and Short Form (SF)12 are widely used generic health-related quality of life (HRQoL) questionnaires. They can be used to derive health utility index scores, on a scale where 0 is equivalent to death and 1 represents full health, with scores less than zero representing states "worse than death." We compared EQ-5D or SF-6D health utility index scores in patients with no chronic pain, and chronic pain with and without neuropathic characteristics (NC), and to explore their discriminant ability for pain severity. Self-reported health and chronic pain status was collected as part of a UK general population survey (n=4451). We found moderate agreement between individual dimensions of EQ-5D and SF-6D, with most highly correlated dimensions found for mental health and anxiety/depression, role limitations and usual activities, and pain and pain/discomfort. Overall 43% reported full health on the EQ-5D, compared with only 4.2% on the SF-6D. There were significant differences in mean utilities for chronic pain with NC (EQ-5D 0.47 vs SF-6D 0.62) and especially for severe pain (EQ-5D 0.33 vs SF-6D 0.58). On the EQ-5D, 17% of those with chronic pain with NC and 3% without NC scored "worse than death," a state which is not possible using the SF-6D. Health utilities derived from EQ-5D and SF-12/36 can discriminate between group differences for chronic pain with and without NC and greater pain severity. However, the instruments generate widely differing HRQoL scores for the same patient groups. The choice between using the EQ-5D or SF-6D matters greatly when estimating the burden of disease. PMID:25020004

  12. Mapping the FACT-G cancer-specific quality of life instrument to the EQ-5D and SF-6D

    PubMed Central

    2013-01-01

    Objective To help facilitate economic evaluations of oncology treatments, we mapped responses on cancer-specific instrument to generic preference-based measures. Methods Cancer patients (n = 367) completed one cancer-specific instrument, the FACT-G, and two preference-based measures, the EQ-5D and SF-6D. Responses were randomly divided to form development (n = 184) and cross-validation (n = 183) samples. Relationships between the instruments were estimated using ordinary least squares (OLS), generalized linear models (GLM), and censored least absolute deviations (CLAD) regression approaches. The performance of each model was assessed in terms of how well the responses to the cancer-specific instrument predicted EQ-5D and SF-6D utilities using mean absolute error (MAE) and root mean squared error (RMSE). Results Physical, functional, and emotional well-being domain scores of the FACT-G best explained the EQ-5D and SF-6D. In terms of accuracy of prediction as measured in RMSE, the CLAD model performed best for the EQ-5D (RMSE = 0.095) whereas the GLM model performed best for the SF-6D (RMSE = 0.061). The GLM predicted SF-6D scores matched the observed values more closely than the CLAD and OLS. Conclusion Our results demonstrate that the estimation of both EQ-5D and SF-6D utility indices using the FACT-G responses can be achieved. The CLAD model for the EQ-5D and the GLM model for the SF-6D are recommended. Thus, it is possible to estimate quality-adjusted life years for economic evaluation from studies where only cancer-specific instrument have been administered. PMID:24289488

  13. Weld electrode cooling study

    NASA Astrophysics Data System (ADS)

    Masters, Robert C.; Simon, Daniel L.

    1999-03-01

    The U.S. auto/truck industry has been mandated by the Federal government to continuously improve their fleet average gas mileage, measured in miles per gallon. Several techniques are typically used to meet these mandates, one of which is to reduce the overall mass of cars and trucks. To help accomplish this goal, lighter weight sheet metal parts, with smaller weld flanges, have been designed and fabricated. This paper will examine the cooling characteristics of various water cooled weld electrodes and shanks used in resistance spot welding applications. The smaller weld flanges utilized in modern vehicle sheet metal fabrications have increased industry's interest in using one size of weld electrode (1/2 inch diameter) for certain spot welding operations. The welding community wants more data about the cooling characteristics of these 1/2 inch weld electrodes. To hep define the cooling characteristics, an infrared radiometer thermal vision system (TVS) was used to capture images (thermograms) of the heating and cooling cycles of several size combinations of weld electrodes under typical production conditions. Tests results will show why the open ended shanks are more suitable for cooling the weld electrode assembly then closed ended shanks.

  14. Discharge processes of UV pre-ionized electric-discharge pulsed DF laser

    NASA Astrophysics Data System (ADS)

    Pan, Qikun; Xie, Jijiang; Shao, Chunlei; Wang, Chunrui; Shao, Mingzhen; Guo, Jin

    2016-03-01

    The discharge processes of ultraviolet (UV) pre-ionized electric-discharge pulsed DF laser operating with a SF6-D2 gas mixture are studied. A mathematical model based on continuity equation of electrons and Kirchhoff equations for discharge circuit is established to describe the discharge processes. Voltage and current waveforms of main discharge and voltage waveforms of pre-ionization are solved numerically utilizing the model. The calculations correctly display some physical processes, such as the delay time between pre-ionization and main discharge, breakdown of the main electrode and self-sustained volume discharge (SSVD). The results of theory are consistent with the experiments, which are performed in our non-chain pulsed DF laser. Then the delay inductance and peak capacitance are researched to analyze their influences on discharge processes, and the circuit parameters of DF laser are given which is useful to improve the discharge stability.

  15. Nonsequential double ionization of molecules

    SciTech Connect

    Prauzner-Bechcicki, Jakub S.; Sacha, Krzysztof; Zakrzewski, Jakub; Eckhardt, Bruno

    2005-03-01

    Double ionization of diatomic molecules by short linearly polarized laser pulses is analyzed. We consider the final stage of the ionization process, that is the decay of a highly excited two electron molecule, which is formed after rescattering. The saddles of the effective adiabatic potential energy close to which simultaneous escape of electrons takes place are identified. Numerical simulations of the ionization of molecules show that the process can be dominated by either sequential or nonsequential events. In order to increase the ratio of nonsequential to sequential ionizations very short laser pulses should be applied.

  16. Comparing Social Stories™ to Cool versus Not Cool

    ERIC Educational Resources Information Center

    Leaf, Justin B.; Mitchell, Erin; Townley-Cochran, Donna; McEachin, John; Taubman, Mitchell; Leaf, Ronald

    2016-01-01

    In this study we compared the cool versus not cool procedure to Social Stories™ for teaching various social behaviors to one individual diagnosed with autism spectrum disorder. The researchers randomly assigned three social skills to the cool versus not cool procedure and three social skills to the Social Stories™ procedure. Naturalistic probes…

  17. Cool Flame Quenching

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Chapek, Richard

    2001-01-01

    Cool flame quenching distances are generally presumed to be larger than those associated with hot flames, because the quenching distance scales with the inverse of the flame propagation speed, and cool flame propagation speeds are often times slower than those associated with hot flames. To date, this presumption has never been put to a rigorous test, because unstirred, non-isothermal cool flame studies on Earth are complicated by natural convection. Moreover, the critical Peclet number (Pe) for quenching of cool flames has never been established and may not be the same as that associated with wall quenching due to conduction heat loss in hot flames, Pe approx. = 40-60. The objectives of this ground-based study are to: (1) better understand the role of conduction heat loss and species diffusion on cool flame quenching (i.e., Lewis number effects), (2) determine cool flame quenching distances (i.e, critical Peclet number, Pe) for different experimental parameters and vessel surface pretreatments, and (3) understand the mechanisms that govern the quenching distances in premixtures that support cool flames as well as hot flames induced by spark-ignition. Objective (3) poses a unique fire safety hazard if conditions exist where cool flame quenching distances are smaller than those associated with hot flames. For example, a significant, yet unexplored risk, can occur if a multi-stage ignition (a cool flame that transitions to a hot flame) occurs in a vessel size that is smaller than that associated with the hot quenching distance. To accomplish the above objectives, a variety of hydrocarbon-air mixtures will be tested in a static reactor at elevated temperature in the laboratory (1g). In addition, reactions with chemical induction times that are sufficiently short will be tested aboard NASA's KC-135 microgravity (mu-g) aircraft. The mu-g results will be compared to a numerical model that includes species diffusion, heat conduction, and a skeletal kinetic mechanism

  18. Investigation and simulation of muon cooling rings with tilted solenoids

    SciTech Connect

    Valeri I. Balbekov

    2003-05-28

    Alternating solenoid focused muon cooling ring without special bending magnets is considered and investigate in detail. Both fringe field between solenoid coils with opposite directed current, and an inclination of the coils in vertical plane are used to provide a bending and closing of the particle trajectories. Realistic (Maxwellian) magnetic field is calculated and used for a simulation. Methodic is developed and applied to find closed orbit at any energy, dispersion, region of stability, and other conventional accelerator characteristics. Earlier proposed RFOFO cooling ring with 200 MHz RF system and liquid hydrogen absorbers is investigated in detail. After an optimization, normalized 6D emittance about 20 mm{sup 3} and transmission 57% are obtained.

  19. Cool WISPs for stellar cooling excesses

    NASA Astrophysics Data System (ADS)

    Giannotti, Maurizio; Irastorza, Igor; Redondo, Javier; Ringwald, Andreas

    2016-05-01

    Several stellar systems (white dwarfs, red giants, horizontal branch stars and possibly the neutron star in the supernova remnant Cassiopeia A) show a mild preference for a non-standard cooling mechanism when compared with theoretical models. This exotic cooling could be provided by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP or a massless HP represent the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO and the massless HP requires a multi TeV energy scale of new physics that might be accessible at the LHC.

  20. The Effects of Partial Ionization on Prominence Mass Formation

    NASA Astrophysics Data System (ADS)

    Karpen, J. T.; Olson, K.; DeVore, C. R.; Martinez Gomez, D.; Sokolov, I.

    2015-12-01

    The origin of the prominence mass has been an open question since this cool plasma suspended in the hot corona was first discovered. We have known for a long time that the mass must come from the chromosphere, but it is unclear whether this mass is lifted bodily through magnetic levitation, injected by reconnection-driven upflows, or driven from the chromosphere by evaporation and then condensed. One evaporation-condensation scenario, the thermal nonequilibrium (TNE) model, is the most fully developed, quantitative model for the prominence plasma to date. In the TNE scenario, localized heating concentrated at the coronal loop footpoints produces chromospheric evaporation, filling the flux tube with hot, dense plasma that subsequently collapses radiatively to form cool condensations. Thus far this model has been successful in explaining the key properties of the long, persistent threads and small, highly dynamic, transient blobs in prominences, the damping of large-amplitude field-aligned prominence oscillations, the appearance of horn-shaped features above the cool prominence in EUV images of coronal cavities, and coronal rain in the ambient corona. To date, all studies of TNE have assumed that the plasma is fully ionized, which is appropriate for the hot coronal gas but unrealistic for the cool plasma below ~30,000 K. The energetics, dynamics, and evolutionary time scales of the TNE process are expected to be altered when the effects of ionization and recombination are considered. We have modified ARGOS, our 1D hydrodynamic code with adaptive mesh refinement, to include an equation of state that accounts for the effects of partial ionization of the plasma over a wide range of temperatures and densities. We will discuss the results of these simulations and their comparison with our previous studies of TNE in typical filament-supporting flux tubes. This work was partially supported by NASA's LWS Strategic Capability program.

  1. Ionizing radiation detector

    DOEpatents

    Thacker, Louis H.

    1990-01-01

    An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

  2. Ionized cluster beam deposition

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.

    1983-01-01

    Ionized Cluster Beam (ICB) deposition, a new technique originated by Takagi of Kyoto University in Japan, offers a number of unique capabilities for thin film metallization as well as for deposition of active semiconductor materials. ICB allows average energy per deposited atom to be controlled and involves impact kinetics which result in high diffusion energies of atoms on the growth surface. To a greater degree than in other techniques, ICB involves quantitative process parameters which can be utilized to strongly control the characteristics of films being deposited. In the ICB deposition process, material to be deposited is vaporized into a vacuum chamber from a confinement crucible at high temperature. Crucible nozzle configuration and operating temperature are such that emerging vapor undergoes supercondensation following adiabatic expansion through the nozzle.

  3. Multiphoton ionization of Uracil

    NASA Astrophysics Data System (ADS)

    Prieto, Eladio; Martinez, Denhi; Guerrero, Alfonso; Alvarez, Ignacio; Cisneros, Carmen

    2016-05-01

    Multiphoton ionization and dissociation of Uracil using a Reflectron time of flight spectrometer was performed along with radiation from the second harmonic of a Nd:YAG laser. Uracil is one of the four nitrogen bases that belong to RNA. The last years special interest has been concentrated on the study of the effects under UV radiation in nucleic acids1 and also in the role that this molecule could have played in the origin and development of life on our planet.2 The MPI mass spectra show that the presence and intensity of the resulting ions strongly depend on the density power. The identification of the ions in the mass spectra is presented. The results are compared with those obtained in other laboratories under different experimental conditions and some of them show partial agreement.3 The present work was supported by CONACYT-Mexico Grant 165410 and DGAPA UNAM Grant IN101215 and IN102613.

  4. Amorphous silicon ionizing particle detectors

    DOEpatents

    Street, R.A.; Mendez, V.P.; Kaplan, S.N.

    1988-11-15

    Amorphous silicon ionizing particle detectors having a hydrogenated amorphous silicon (a--Si:H) thin film deposited via plasma assisted chemical vapor deposition techniques are utilized to detect the presence, position and counting of high energy ionizing particles, such as electrons, x-rays, alpha particles, beta particles and gamma radiation. 15 figs.

  5. Amorphous silicon ionizing particle detectors

    DOEpatents

    Street, Robert A.; Mendez, Victor P.; Kaplan, Selig N.

    1988-01-01

    Amorphous silicon ionizing particle detectors having a hydrogenated amorphous silicon (a--Si:H) thin film deposited via plasma assisted chemical vapor deposition techniques are utilized to detect the presence, position and counting of high energy ionizing particles, such as electrons, x-rays, alpha particles, beta particles and gamma radiation.

  6. Jahn-Teller effect in van der Waals complexes; Ar-C6H6+ and Ar-C6D6+

    NASA Astrophysics Data System (ADS)

    van der Avoird, Ad; Lotrich, Victor F.

    2004-06-01

    The two asymptotically degenerate potential energy surfaces of argon interacting with the X˜ 2E1g ground state benzene+ cation were calculated ab initio from the interaction energy of the neutral Ar-benzene complex given by Koch et al. [J. Chem. Phys. 111, 198 (1999)] and the difference of the geometry-dependent ionization energies of the complex and the benzene monomer computed by the outer valence Green's function method. Coinciding minima in the two potential surfaces of the ionic complex occur for Ar on the C6v symmetry axis of benzene+ (the z axis) at ze=3.506 Å. The binding energy De of 520 cm-1 is only 34% larger than the value for the neutral Ar-benzene complex. The higher one of the two surfaces is similar in shape to the neutral Ar-benzene potential, the lower potential is much flatter in the (x,y) bend direction. Nonadiabatic (Jahn-Teller) coupling was taken into account by transformation of the two adiabatic potentials to a two-by-two matrix of diabatic potentials. This transformation is based on the assumption that the adiabatic states of the Ar-benzene+ complex geometrically follow the Ar atom. Ab initio calculations of the nonadiabatic coupling matrix element between the adiabatic states with the two-state-averaged CAS-SCF(5,6) method confirmed the validity of this assumption. The bound vibronic states of both Ar-C6H6+ and Ar-C6D6+ were computed with this two-state diabatic model in a basis of three-dimensional harmonic oscillator functions for the van der Waals modes. The binding energy D0=480 cm-1 of the perdeuterated complex agrees well with the experimental upper bound of 485 cm-1. The ground and excited vibronic levels and wave functions were used, with a simple model dipole function, to generate a theoretical far-infrared spectrum. Strong absorption lines were found at 10.1 cm-1 (bend) and 47.9 cm-1 (stretch) that agree well with measurements. The unusually low bend frequency is related to the flatness of the lower adiabatic potential in the

  7. A novel compound 6D-offset simulating phantom and quality assurance program for stereotactic image-guided radiation therapy system.

    PubMed

    Yuen Kan Ngar, Dennis; Lok-Man Cheung, Michael; Koon-Ming Kam, Michael; Poon, Wai-Sang; Tak-Cheung Chan, Anthony

    2013-01-01

    A comprehensive quality assurance (QA) device cum program was developed for the commissioning and routine testing of the 6D IGRT systems. In this article, both the new QA system and the BrainLAB IGRT system which was added onto a Varian Clinac were evaluated. A novel compound 6D-offset simulating phantom was designed and fabricated in the Prince of Wales Hospital (PWH), Hong Kong. The QA program generated random compound 6D-offset values. The 6D phantom was simply set up and shifted accordingly. The BrainLAB ExacTrac X-ray IGRT system detected the offsets and then corrected the phantom position automatically through the robotic couch. Routine QA works facilitated data analyses of the detection errors, the correction errors, and the correlations. Fifty sets of data acquired in 2011 in PWH were thoroughly analyzed. The 6D component detection errors and correction errors of the IGRT system were all within ± 1 mm and ± 1° individually. Translational and rotational scalar resultant errors were found to be 0.50 ± 0.27 mm and 0.54 ± 0.23°, respectively. Most individual component errors were shown to be independent of their original offset values. The system characteristics were locally established. The BrainLAB 6D IGRT system added onto a regular linac is sufficiently precise for stereotactic RT. This new QA methodology is competent to assure the IGRT system overall integrity. Annual grand analyses are recommended to check local system consistency and for external cross comparison. The target expansion policy of 1.5 mm 3D margin from CTV to PTV is confirmed for this IGRT system currently in PWH. PMID:24257294

  8. Cooling in a compound bucket

    SciTech Connect

    Shemyakin, A.; Bhat, C.; Broemmelsiek, D.; Burov, A.; Hu, M.; /Fermilab

    2007-09-01

    Electron cooling in the Fermilab Recycler ring is found to create correlation between longitudinal and transverse tails of the antiproton distribution. By separating the core of the beam from the tail and cooling the tail using 'gated' stochastic cooling while applying electron cooling on the entire beam, one may be able to significantly increase the overall cooling rate. In this paper, we describe the procedure and first experimental results.

  9. Passive containment cooling system

    DOEpatents

    Billig, P.F.; Cooke, F.E.; Fitch, J.R.

    1994-01-25

    A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA. 1 figure.

  10. STOCHASTIC COOLING FOR RHIC.

    SciTech Connect

    BLASKIEWICZ,M.BRENNAN,J.M.CAMERON,P.WEI,J.

    2003-05-12

    Emittance growth due to Intra-Beam Scattering significantly reduces the heavy ion luminosity lifetime in RHIC. Stochastic cooling of the stored beam could improve things considerably by counteracting IBS and preventing particles from escaping the rf bucket [1]. High frequency bunched-beam stochastic cooling is especially challenging but observations of Schottky signals in the 4-8 GHz band indicate that conditions are favorable in RHIC [2]. We report here on measurements of the longitudinal beam transfer function carried out with a pickup kicker pair on loan from FNAL TEVATRON. Results imply that for ions a coasting beam description is applicable and we outline some general features of a viable momentum cooling system for RHIC.

  11. Cooling of neutron stars

    NASA Technical Reports Server (NTRS)

    Pethick, C. J.

    1992-01-01

    It is at present impossible to predict the interior constitution of neutron stars based on theory and results from laboratory studies. It has been proposed that it is possible to obtain information on neutron star interiors by studying thermal radiation from their surfaces, because neutrino emission rates, and hence the temperature of the central part of a neutron star, depend on the properties of dense matter. The theory predicts that neutron stars cool relatively slowly if their cores are made up of nucleons, and cool faster if the matter is in an exotic state, such as a pion condensate, a kaon condensate, or quark matter. This view has recently been questioned by the discovery of a number of other processes that could lead to copious neutrino emission and rapid cooling.

  12. Monitoring Cray Cooling Systems

    SciTech Connect

    Maxwell, Don E; Ezell, Matthew A; Becklehimer, Jeff; Donovan, Matthew J; Layton, Christopher C

    2014-01-01

    While sites generally have systems in place to monitor the health of Cray computers themselves, often the cooling systems are ignored until a computer failure requires investigation into the source of the failure. The Liebert XDP units used to cool the Cray XE/XK models as well as the Cray proprietary cooling system used for the Cray XC30 models provide data useful for health monitoring. Unfortunately, this valuable information is often available only to custom solutions not accessible by a center-wide monitoring system or is simply ignored entirely. In this paper, methods and tools used to harvest the monitoring data available are discussed, and the implementation needed to integrate the data into a center-wide monitoring system at the Oak Ridge National Laboratory is provided.

  13. Passive containment cooling system

    DOEpatents

    Billig, Paul F.; Cooke, Franklin E.; Fitch, James R.

    1994-01-01

    A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA.

  14. Ionization detection system for aerosols

    DOEpatents

    Jacobs, Martin E.

    1977-01-01

    This invention relates to an improved smoke-detection system of the ionization-chamber type. In the preferred embodiment, the system utilizes a conventional detector head comprising a measuring ionization chamber, a reference ionization chamber, and a normally non-conductive gas triode for discharging when a threshold concentration of airborne particulates is present in the measuring chamber. The improved system utilizes a measuring ionization chamber which is modified to minimize false alarms and reductions in sensitivity resulting from changes in ambient temperature. In the preferred form of the modification, an annular radiation shield is mounted about the usual radiation source provided to effect ionization in the measuring chamber. The shield is supported by a bimetallic strip which flexes in response to changes in ambient temperature, moving the shield relative to the source so as to vary the radiative area of the source in a manner offsetting temperature-induced variations in the sensitivity of the chamber.

  15. Microwave continuum measurements and estimates of mass loss rates for cool giants and supergiants

    NASA Technical Reports Server (NTRS)

    Drake, S. A.; Linsky, J. L.

    1986-01-01

    Attention is given to the results of a sensitive, 6-cm radio continuum survey conducted with the NRAO VLA of 39 of the nearest single cool giants and supergiants of G0-M5 spectral types; the survey was conducted in order to obtain accurate measurements of the mass loss rates of ionized gas for a representative sample of such stars, in order to furnish constraints for, and a better understanding of, the total mass loss rates. The inferred angular diameters for the cool giant sources are noted to be twice as large as photospheric angular diameters, implying that these stars are surrounded by extended chromospheres containing warm partially ionized gas.

  16. Analysis of tear glucose concentration with electrospray ionization mass spectrometry.

    PubMed

    Taormina, Christopher R; Baca, Justin T; Asher, Sanford A; Grabowski, Joseph J; Finegold, David N

    2007-02-01

    We have developed a mass spectrometry-based method that allows one to accurately determine the glucose concentration of tear fluid. We used a 1 microL micro-capillary to collect tear fluid from the tear meniscus with minimal irritation of the eye. We analyzed the 1 muL volume of collected tear fluid with liquid-chromatography electrospray ionization mass spectrometry with the use of D-glucose-6,6-d2 as an internal standard. Repeated measurements and a recovery experiment on pooled, onion-induced tears showed that the analysis of the glucose in tears was precise (4% relative standard deviation) and provided 100% recovery. We found the tear glucose concentration of one fasting nondiabetic subject to be 13 to 51 microM while the onion-induced tear glucose concentration of a different nondiabetic subject to be 211 to 256 microM. PMID:17084090

  17. Analysis of Tear Glucose Concentration with Electrospray Ionization Mass Spectrometry

    PubMed Central

    Taormina, Christopher R.; Baca, Justin T.; Finegold, David N.; Asher, Sanford A.; Grabowski, Joseph J.

    2007-01-01

    We have developed a mass spectrometry-based method which allows one to accurately determine the glucose concentration of tear fluid. We used a 1 μL micro-capillary to collect tear fluid from the tear meniscus with minimal irritation of the eye. We analyzed the 1 μL volume of collected tear fluid with liquid-chromatography electrospray ionization mass spectrometry with the use of D-glucose-6,6-d2 as an internal standard. Repeated measurements and a recovery experiment on pooled, onion-induced tears showed that the analysis of the glucose in tears was precise (4% relative standard deviation) and provided 100% recovery. We found the tear glucose concentration of one fasting non-diabetic subject to be 13 to 51 μM while the onion-induced tear glucose concentration of a different non-diabetic subject to be 211 to 256 μM. PMID:17084090

  18. Combustor liner cooling system

    DOEpatents

    Lacy, Benjamin Paul; Berkman, Mert Enis

    2013-08-06

    A combustor liner is disclosed. The combustor liner includes an upstream portion, a downstream end portion extending from the upstream portion along a generally longitudinal axis, and a cover layer associated with an inner surface of the downstream end portion. The downstream end portion includes the inner surface and an outer surface, the inner surface defining a plurality of microchannels. The downstream end portion further defines a plurality of passages extending between the inner surface and the outer surface. The plurality of microchannels are fluidly connected to the plurality of passages, and are configured to flow a cooling medium therethrough, cooling the combustor liner.

  19. Cyclic cooling algorithm

    SciTech Connect

    Rempp, Florian; Mahler, Guenter; Michel, Mathias

    2007-09-15

    We introduce a scheme to perform the cooling algorithm, first presented by Boykin et al. in 2002, for an arbitrary number of times on the same set of qbits. We achieve this goal by adding an additional SWAP gate and a bath contact to the algorithm. This way one qbit may repeatedly be cooled without adding additional qbits to the system. By using a product Liouville space to model the bath contact we calculate the density matrix of the system after a given number of applications of the algorithm.

  20. Anomalous law of cooling

    SciTech Connect

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Rubí, J. Miguel; Oliveira, Fernando A.

    2015-03-14

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton’s law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  1. Superconductor rotor cooling system

    DOEpatents

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2002-01-01

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  2. Anomalous law of cooling.

    PubMed

    Lapas, Luciano C; Ferreira, Rogelma M S; Rubí, J Miguel; Oliveira, Fernando A

    2015-03-14

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics. PMID:25770525

  3. Anomalous law of cooling

    NASA Astrophysics Data System (ADS)

    Lapas, Luciano C.; Ferreira, Rogelma M. S.; Rubí, J. Miguel; Oliveira, Fernando A.

    2015-03-01

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics.

  4. Superconductor rotor cooling system

    DOEpatents

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed; Schwall, Robert E.; Driscoll, David I.; Shoykhet, Boris A.

    2004-11-02

    A system for cooling a superconductor device includes a cryocooler located in a stationary reference frame and a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with a rotating reference frame in which the superconductor device is located. A method of cooling a superconductor device includes locating a cryocooler in a stationary reference frame, and transferring heat from a superconductor device located in a rotating reference frame to the cryocooler through a closed circulation system external to the cryocooler. The closed circulation system interfaces the stationary reference frame with the rotating reference frame.

  5. Research on cooling effectiveness in stepped slot film cooling vane

    NASA Astrophysics Data System (ADS)

    Li, Yulong; Wu, Hong; Zhou, Feng; Rong, Chengjun

    2016-06-01

    As one of the most important developments in air cooling technology for hot parts of the aero-engine, film cooling technology has been widely used. Film cooling hole structure exists mainly in areas that have high temperature, uneven cooling effectiveness issues when in actual use. The first stage turbine vanes of the aero-engine consume the largest portion of cooling air, thereby the research on reducing the amount of cooling air has the greatest potential. A new stepped slot film cooling vane with a high cooling effectiveness and a high cooling uniformity was researched initially. Through numerical methods, the affecting factors of the cooling effectiveness of a vane with the stepped slot film cooling structure were researched. This paper focuses on the cooling effectiveness and the pressure loss in different blowing ratio conditions, then the most reasonable and scientific structure parameter can be obtained by analyzing the results. The results show that 1.0 mm is the optimum slot width and 10.0 is the most reasonable blowing ratio. Under this condition, the vane achieved the best cooling result and the highest cooling effectiveness, and also retained a low pressure loss.

  6. IEHI: Ionization Equilibrium for Heavy Ions

    NASA Astrophysics Data System (ADS)

    Cranmer, Steven R.

    2015-07-01

    IEHI, written in Fortran, outputs a simple "coronal" ionization equilibrium (i.e., collisional ionization and auto-ionization balanced by radiative and dielectronic recombination) for a plasma at a given electron temperature.

  7. Candidates for laser cooling of atomic anions: La{sup -} versus Os{sup -}

    SciTech Connect

    Pan, Lin; Beck, Donald R.

    2010-07-15

    This brief report is a follow-up to the recent proposal to use La{sup -} as another candidate, in addition to Os{sup -}, in laser cooling of anions, which can then be used to cool antiprotons sympathetically. Using the relativistic configuration interaction formalism, we calculate the photodetachment cross sections of the upper laser cooling state La{sup -} 5d6s{sup 2}6p {sup 3}D{sub 1} and Os{sup -} 5d{sup 6}6s{sup 2}6p {sup 6}D{sub 9/2}. Our results show that La{sup -} has a very similar two-photon detachment loss as Os{sup -}, retaining it as another promising candidate for cooling antiprotons sympathetically.

  8. Turbomachine rotor with improved cooling

    DOEpatents

    Hultgren, K.G.; McLaurin, L.D.; Bertsch, O.L.; Lowe, P.E.

    1998-05-26

    A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn. 5 figs.

  9. Turbomachine rotor with improved cooling

    DOEpatents

    Hultgren, Kent Goran; McLaurin, Leroy Dixon; Bertsch, Oran Leroy; Lowe, Perry Eugene

    1998-01-01

    A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn.

  10. Measure Guideline: Ventilation Cooling

    SciTech Connect

    Springer, D.; Dakin, B.; German, A.

    2012-04-01

    The purpose of this measure guideline is to provide information on a cost-effective solution for reducing cooling system energy and demand in homes located in hot-dry and cold-dry climates. This guideline provides a prescriptive approach that outlines qualification criteria, selection considerations, and design and installation procedures.

  11. Electron Cooling of RHIC

    SciTech Connect

    I. Ben-Zvi; D.S. Barton; D.B. Beavis; M. Blaskiewicz; J.M. Brennan; A. Burrill; R. Calaga; P. Cameron; X.Y. Chang; R. Connolly; Yu.I. Eidelman; A.V. Fedotov; W. Fischer; D.M. Gassner; H. Hahn; M. Harrison; A. Hershcovitch; H.-C. Hseuh; A.K. Jain; P.D.J. Johnson; D. Kayran; J. Kewisch; R.F. Lambiase; V. Litvinenko; W.W. MacKay; G.J. Mahler; N. Malitsky; G.T. McIntyre; W. Meng; K.A.M. Mirabella; C. Montag; T.C.N. Nehring; T. Nicoletti; B. Oerter; G. Parzen; D. Pate; J. Rank; T. Rao; T. Roser; T. Russo; J. Scaduto; K. Smith; D. Trbojevic; G. Wang; J. Wei; N.W.W. Williams; K.-C. Wu; V. Yakimenko; A. Zaltsman; Y. Zhao; D.T. Abell; D.L. Bruhwiler; H. Bluem; A. Burger; M.D. Cole; A.J. Favale; D. Holmes; J. Rathke; T. Schultheiss; A.M.M. Todd; A.V. Burov; S. Nagaitsev; J.R. Delayen; Y.S. Derbenev; L. W. Funk; P. Kneisel; L. Merminga; H.L. Phillips; J.P. Preble; I. Koop; V.V. Parkhomchuk; Y.M. Shatunov; A.N. Skrinsky; I. Koop; V.V. Parkhomchuk; Y.M. Shatunov; A.N. Skrinsky; J.S. Sekutowicz

    2005-05-16

    We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.agsrhichome.bnl.gov/eCool/.

  12. Guide to Cool Roofs

    SciTech Connect

    2011-02-01

    Traditional dark-colored roofing materials absorb sunlight, making them warm in the sun and increasing the need for air conditioning. White or special "cool color" roofs absorb less sunlight, stay cooler in the sun and transmit less heat into the building.

  13. Deep mine cooling system

    SciTech Connect

    Conan, J.

    1984-11-06

    A deep mine cooling system comprising a compressor supplied with air and rotatively driven by a motor and an expansion turbine supplied with compressed air from said compressor and driving an actuating unit, wherein the compressed air, after leaving the compressor but prior to reaching the expansion turbine, passes through a steam generator whose output provides the energy required to operate an absorption refrigeration machine used to cool utility water for mining, said compressed air on leaving the steam generator going to a first heat exchanger in which it yields calories to a water circuit comprising a second heat exchanger, said second heat exchanger giving off the calories absorbed by the water in the first heat exchanger to the air fed by the second heat exchanger to a drying cell that is regenerated by said air from the second heat exchanger, said drying cell being part of a set of two cells working in alternation, the other cell in the set receiving the compressed air from the first heat exchanger, such that the compressed air is fed to said expansion turbine after leaving said drying unit, and wherein the air exhausted from said expansion turbine is sent to a third heat exchanger after which it is distributed according to the needs of the mine, said third exchanger being traversed by the water collected in the mine, cooled in said exchanger and circulated upon leaving said exchanger to meet the cool water requirements of the mine.

  14. Elementary stochastic cooling

    SciTech Connect

    Tollestrup, A.V.; Dugan, G

    1983-12-01

    Major headings in this review include: proton sources; antiproton production; antiproton sources and Liouville, the role of the Debuncher; transverse stochastic cooling, time domain; the accumulator; frequency domain; pickups and kickers; Fokker-Planck equation; calculation of constants in the Fokker-Planck equation; and beam feedback. (GHT)

  15. Warm and Cool Cityscapes

    ERIC Educational Resources Information Center

    Jubelirer, Shelly

    2012-01-01

    Painting cityscapes is a great way to teach first-grade students about warm and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,…

  16. COOLING TOWER PLUME MODEL

    EPA Science Inventory

    A review of recently reported cooling tower plume models yields none that is universally accepted. The entrainment and drag mechanisms and the effect of moisture on the plume trajectory are phenomena which are treated differently by various investigators. In order to better under...

  17. Transpiration Cooling Experiment

    NASA Technical Reports Server (NTRS)

    Song, Kyo D.; Ries, Heidi R.; Scotti, Stephen J.; Choi, Sang H.

    1997-01-01

    The transpiration cooling method was considered for a scram-jet engine to accommodate thermally the situation where a very high heat flux (200 Btu/sq. ft sec) from hydrogen fuel combustion process is imposed to the engine walls. In a scram-jet engine, a small portion of hydrogen fuel passes through the porous walls of the engine combustor to cool the engine walls and at the same time the rest passes along combustion chamber walls and is preheated. Such a regenerative system promises simultaneously cooling of engine combustor and preheating the cryogenic fuel. In the experiment, an optical heating method was used to provide a heat flux of 200 Btu/sq. ft sec to the cylindrical surface of a porous stainless steel specimen which carried helium gas. The cooling efficiencies by transpiration were studied for specimens with various porosity. The experiments of various test specimens under high heat flux have revealed a phenomenon that chokes the medium flow when passing through a porous structure. This research includes the analysis of the system and a scaling conversion study that interprets the results from helium into the case when hydrogen medium is used.

  18. High pressure xenon ionization detector

    DOEpatents

    Markey, John K.

    1989-01-01

    A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0.degree. to 30.degree. C.

  19. High pressure xenon ionization detector

    DOEpatents

    Markey, J.K.

    1989-11-14

    A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0 to 30 C. 2 figs.

  20. Laser cooling of solids

    NASA Astrophysics Data System (ADS)

    Nemova, Galina; Kashyap, Raman

    2010-08-01

    Laser cooling of solids, sometimes also known as optical refrigeration, is a fast developing area of optical science, investigating the interaction of light with condensed matter. Apart from being of fundamental scientific interest, this topic addresses a very important practical issue: design and construction of laser pumped solid-state cryocoolers, which are compact, free from mechanical vibrations, moving parts, fluids and can cause only low electromagnetic interference in the cooled area. The optical cryocooler has a broad area of applications such as in the development of magnetometers for geophysical sensors, in biomedical sensing and can be beneficial for satellite instrumentations and small sensors, where compactness and the lack of vibrations are very important. Simply, a laser cooler works on the conversion of low energy pump photons into high-energy anti-Stokes fluorescence photons by extracting some of the phonons (heat energy) in a material. That is, the process of laser cooling of solids is based on anti-Stokes fluorescence also known as luminescence upconversion, when light quanta in the red tail of the absorption spectrum are absorbed from a pump laser, and blue-shifted photons are spontaneously emitted. The extra energy extracted from the solid-state lattice in the form of the phonons is the quanta of vibrational energy which generates heat. The idea to cool solids with anti-Stokes fluorescence was proposed in 1929 by Peter Pringsheim and first demonstrated experimentally by Epstein's research team in 1995. In 1999, Steven Bowman proposed to use the optical refrigeration by anti-Stokes fluorescence within the laser medium to balance the heat generated by the Stokes shifted stimulated emission in a high-power solid-state bulk laser. Such a laser without internal heating named radiation-balanced or athermal laser was experimentally demonstrated for the first time in 2002. At the present time laser cooling of solids can be largely divided into three

  1. Traveling Wave RF Systems for Helical Cooling Channels

    SciTech Connect

    Yonehara, K.; Lunin, A.; Moretti, A.; Popovic, M.; Romanov, G.; Neubauer, M.; Johnson, R.P.; Thorndahl, L.; /CERN

    2009-05-01

    The great advantage of the helical ionization cooling channel (HCC) is its compact structure that enables the fast cooling of muon beam 6-dimensional phase space. This compact aspect requires a high average RF gradient, with few places that do not have cavities. Also, the muon beam is diffuse and requires an RF system with large transverse and longitudinal acceptance. A traveling wave system can address these requirements. First, the number of RF power coupling ports can be significantly reduced compared with our previous pillbox concept. Secondly, by adding a nose on the cell iris, the presence of thin metal foils traversed by the muons can possibly be avoided. We show simulations of the cooling performance of a traveling wave RF system in a HCC, including cavity geometries with inter-cell RF power couplers needed for power propagation.

  2. Iron ionization and recombination rates and ionization equilibrium

    NASA Technical Reports Server (NTRS)

    Arnaud, M.; Raymond, J.

    1992-01-01

    In the past few years important progress has been made on the knowledge of ionization and recombination rates of iron, an astrophysically abundant heavy element and a major impurity in laboratory fusion devices. We make a critical review of the existing data on ionization and dielectronic recombination and present new computations of radiative recombination rate coefficients of Fe(+14) through Fe(+25) using the photoionization cross sections of Clark et al. (1986). We provide analytical fits to the recommended data (direct ionization and excitation-autoionization cross sections; radiative and dielectronic recombination rate coefficients). Finally we determine the iron ionic fractions at ionization equilibrium and compare them with previous computations as well as with observational data.

  3. Balance maintenance in high-speed motion of humanoid robot arm-based on the 6D constraints of momentum change rate.

    PubMed

    Zhang, Da-song; Xiong, Rong; Wu, Jun; Chu, Jian

    2014-01-01

    Based on the 6D constraints of momentum change rate (CMCR), this paper puts forward a real-time and full balance maintenance method for the humanoid robot during high-speed movement of its 7-DOF arm. First, the total momentum formula for the robot's two arms is given and the momentum change rate is defined by the time derivative of the total momentum. The author also illustrates the idea of full balance maintenance and analyzes the physical meaning of 6D CMCR and its fundamental relation to full balance maintenance. Moreover, discretization and optimization solution of CMCR has been provided with the motion constraint of the auxiliary arm's joint, and the solving algorithm is optimized. The simulation results have shown the validity and generality of the proposed method on the full balance maintenance in the 6 DOFs of the robot body under 6D CMCR. This method ensures 6D dynamics balance performance and increases abundant ZMP stability margin. The resulting motion of the auxiliary arm has large abundance in joint space, and the angular velocity and the angular acceleration of these joints lie within the predefined limits. The proposed algorithm also has good real-time performance. PMID:24883404

  4. Microwave reflectometer ionization sensor

    NASA Technical Reports Server (NTRS)

    Seals, Joseph; Fordham, Jeffrey A.; Pauley, Robert G.; Simonutti, Mario D.

    1993-01-01

    The development of the Microwave Reflectometer Ionization Sensor (MRIS) Instrument for use on the Aeroassist Flight Experiment (AFE) spacecraft is described. The instrument contract was terminated, due to cancellation of the AFE program, subsequent to testing of an engineering development model. The MRIS, a four-frequency reflectometer, was designed for the detection and location of critical electron density levels in spacecraft reentry plasmas. The instrument would sample the relative magnitude and phase of reflected signals at discrete frequency steps across 4 GHz bandwidths centered at four frequencies: 20, 44, 95, and 140 GHz. The sampled data would be stored for later processing to calculate the distance from the spacecraft surface to the critical electron densities versus time. Four stepped PM CW transmitter receivers were located behind the thermal protection system of the spacecraft with horn antennas radiating and receiving through an insulating tile. Techniques were developed to deal with interference, including multiple reflections and resonance effects, resulting from the antenna configuration and operating environment.

  5. Optical ionization detector

    DOEpatents

    Wuest, Craig R.; Lowry, Mark E.

    1994-01-01

    An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium.

  6. Optical ionization detector

    DOEpatents

    Wuest, C.R.; Lowry, M.E.

    1994-03-29

    An optical ionization detector wherein a beam of light is split so that one arm passes through a fiber optics and the other arm passes through a gas-filled region, and uses interferometry to detect density changes in a gas when charged particles pass through it. The gas-filled region of the detector is subjected to a high electric field and as a charged particle traverses this gas region electrons are freed from the cathode and accelerated so as to generate an electron avalanche which is collected on the anode. The gas density is effected by the electron avalanche formation and if the index or refraction is proportional to the gas density the index will change accordingly. The detector uses this index change by modulating the one arm of the split light beam passing through the gas, with respect to the other arm that is passed through the fiber optic. Upon recombining of the beams, interference fringe changes as a function of the index change indicates the passage of charged particles through the gaseous medium. 3 figures.

  7. Martian Meteor Ionization Layers

    NASA Technical Reports Server (NTRS)

    Grebowsky, J. M.; Pesnell, W. D.

    1999-01-01

    Small interplanetary grains bombard Mars, like all the solar system planets, and, like all the planets with atmospheres, meteoric ion and atom layers form in the upper atmosphere. We have developed a comprehensive one-dimensional model of the Martian meteoric ionization layer including a full chemical scheme. A persistent layer of magnesium ions should exist around an altitude of 70 km. Unlike the terrestrial case, where the metallic ions are formed via charge-exchange with the ambient ions, Mg(+) in the Martian atmosphere is produced by photoionization. Nevertheless, the predicted metal layer peak densities for Earth and Mars are similar. Diffusion solutions, such as those presented here, should be a good approximation of the metallic ions in regions where the magnetic field is negligible and may provide a significant contribution to the nightside ionosphere. The low ultraviolet absorption of the Martian atmosphere may make Mars an excellent laboratory in which to study meteoric ablation. Resonance lines not seen in the spectra of terrestrial meteors may be visible to a surface observatory in the Martian highlands.

  8. Pulsed helium ionization detection system

    DOEpatents

    Ramsey, Roswitha S.; Todd, Richard A.

    1987-01-01

    A helium ionization detection system is provided which produces stable operation of a conventional helium ionization detector while providing improved sensitivity and linearity. Stability is improved by applying pulsed dc supply voltage across the ionization detector, thereby modifying the sampling of the detectors output current. A unique pulse generator is used to supply pulsed dc to the detector which has variable width and interval adjust features that allows up to 500 V to be applied in pulse widths ranging from about 150 nsec to about dc conditions.

  9. Pulsed helium ionization detection system

    DOEpatents

    Ramsey, R.S.; Todd, R.A.

    1985-04-09

    A helium ionization detection system is provided which produces stable operation of a conventional helium ionization detector while providing improved sensitivity and linearity. Stability is improved by applying pulsed dc supply voltage across the ionization detector, thereby modifying the sampling of the detectors output current. A unique pulse generator is used to supply pulsed dc to the detector which has variable width and interval adjust features that allows up to 500 V to be applied in pulse widths ranging from about 150 nsec to about dc conditions.

  10. Ionizing radiation promotes protozoan reproduction

    SciTech Connect

    Luckey, T.D.

    1986-11-01

    This experiment was performed to determine whether ionizing radiation is essential for maximum growth rate in a ciliated protozoan. When extraneous ionizing radiation was reduced to 0.15 mrad/day, the reproduction rate of Tetrahymena pyriformis was significantly less (P less than 0.01) than it was at near ambient levels, 0.5 or 1.8 mrad/day. Significantly higher growth rates (P less than 0.01) were obtained when chronic radiation was increased. The data suggest that ionizing radiation is essential for optimum reproduction rate in this organism.

  11. Electron Cooling Study for MEIC

    SciTech Connect

    He, Zhang; Douglas, David R.; Derbenev, Yaroslav S.; Zhang, Yuhong

    2015-09-01

    Electron cooling of the ion beams is one critical R&D to achieve high luminosities in JLab's MEIC proposal. In the present MEIC design, a multi-staged cooling scheme is adapted, which includes DC electron cooling in the booster ring and bunched beam electron cooling in the collider ring at both the injection energy and the collision energy. We explored the feasibility of using both magnetized and non-magnetized electron beam for cooling, and concluded that a magnetized electron beam is necessary. Electron cooling simulation results for the newly updated MEIC design is also presented.

  12. Departures from LTE in Cool Stars

    NASA Astrophysics Data System (ADS)

    Mashonkina, L.

    2010-11-01

    Departures from LTE may significantly affect determinations of stellar parameters and chemical abundances of cool stars, in particular, metal-poor stars. We review the application of the non-LTE ionization equilibrium between Ca i and Ca ii to constrain the surface gravity of very metal-poor and hyper metal-poor stars spectroscopically. The few examples from Galactic chemical evolution studies show that our understanding of how nucleosynthesis proceeds throughout Galactic history depends on the accuracy of spectral line formation modelling. Problems of non-LTE modelling of Fe i- Fe ii are also discussed. This research was supported by the Deutsche Forschungsgemeinschaft with grant 436 RUS 17/13/07 and by the Russian Foundation for Basic Research with grant 05-02-39005-GFEN-a.

  13. Ionization-based detectors for gas chromatography.

    PubMed

    Poole, Colin F

    2015-11-20

    The gas phase ionization detectors are the most widely used detectors for gas chromatography. The column and makeup gases commonly used in gas chromatography are near perfect insulators. This facilitates the detection of a minute number of charge carriers facilitating the use of ionization mechanisms of low efficiency while providing high sensitivity. The main ionization mechanism discussed in this report are combustion in a hydrogen diffusion flame (flame ionization detector), surface ionization in a plasma (thermionic ionization detector), photon ionization (photoionization detector and pulsed discharge helium ionization detector), attachment of thermal electrons (electron-capture detector), and ionization by collision with metastable helium species (helium ionization detector). The design, response characteristics, response mechanism, and suitability for fast gas chromatography are the main features summarized in this report. Mass spectrometric detection and atomic emission detection, which could be considered as ionization detectors of a more sophisticated and complex design, are not discussed in this report. PMID:25757823

  14. Measuring Ionization at Extreme Densities

    NASA Astrophysics Data System (ADS)

    Kraus, Dominik; Doeppner, Tilo; Kritcher, Andrea; Bachmann, Benjamin; Fletcher, Luke; Falcone, Roger; Gericke, Dirk; Glenzer, Siegfried; Masters, Nathan; Nora, Ryan; Boehm, Kurt; Divol, Laurent; Landen, Otto; Yi, Austin; Kline, John; Redmer, Ronald; Neumayer, Paul

    2015-11-01

    A precise knowledge of ionization at given temperature and density is crucial in order to properly model compressibility and heat capacity of ICF ablator materials for efficient implosions producing energy gain. Here, we present a new experimental platform to perform spectrally resolved x-ray scattering measurements of ionization, density and temperature in imploding CH or beryllium capsules on the National Ignition Facility. Recording scattered x-rays at 9 keV from a zinc He-alpha plasma source at a scattering angle of 120 degrees, first experiments show strong sensitivity to k-shell ionization, while at the same time constraining density and temperature. This platform will allow for x-ray Thomson scattering studies of dense plasmas with free electron densities up to 1025 cm-3, giving the possibility to investigate effects of continuum lowering and Pauli blocking on the ablator ionization state right before stagnation of the implosion.

  15. Double ionization of atomic cadmium

    SciTech Connect

    Linusson, P.; Fritzsche, S.; Eland, J. H. D.; Hedin, L.; Karlsson, L.; Feifel, R.

    2011-02-15

    We have recorded the double photoionization spectrum of atomic Cd at four different photon energies in the range 40-200 eV. The main channel is single ionization and subsequent decay of excited Cd{sup +} states, some involving Coster-Kronig processes, whereas direct double ionization is found to be weak. The decay of the excited Cd{sup +} states shows a strong selectivity, related to the configuration of the final state. Double ionization leading to the Cd{sup 2+} ground state is investigated in some detail and is found to proceed mainly through ionization and decay of 4d correlation satellites. The most prominent autoionization peaks have been identified with the aid of quantum-mechanical calculations.

  16. Salts Are Mostly NOT Ionized.

    ERIC Educational Resources Information Center

    Hawkes, Stephen J.

    1996-01-01

    Discusses the misconception that salts are completely ionizing in solution, the presence of this error in textbooks, probable origins of the error, covalent bonding and ion pairs, and how to tell students the truth. (MKR)

  17. Calculation of multiphoton ionization processes

    NASA Technical Reports Server (NTRS)

    Chang, T. N.; Poe, R. T.

    1976-01-01

    We propose an accurate and efficient procedure in the calculation of multiphoton ionization processes. In addition to the calculational advantage, this procedure also enables us to study the relative contributions of the resonant and nonresonant intermediate states.

  18. Ionization oscillations in Hall accelerators

    NASA Astrophysics Data System (ADS)

    Barral, S.; Peradzyński, Z.

    2010-01-01

    The underlying mechanism of low-frequency oscillations in Hall accelerators is investigated theoretically. It is shown that relaxation oscillations arise from a competition between avalanche ionization and the advective transport of the working gas. The model derived recovers the slow progression and fast recession of the ionization front. Analytical approximations of the shape of current pulses and of the oscillation frequency are provided for the case of large amplitude oscillations.

  19. Resonance ionization for analytical spectroscopy

    DOEpatents

    Hurst, George S.; Payne, Marvin G.; Wagner, Edward B.

    1976-01-01

    This invention relates to a method for the sensitive and selective analysis of an atomic or molecular component of a gas. According to this method, the desired neutral component is ionized by one or more resonance photon absorptions, and the resultant ions are measured in a sensitive counter. Numerous energy pathways are described for accomplishing the ionization including the use of one or two tunable pulsed dye lasers.

  20. Laser ionization mass spectroscopy

    NASA Astrophysics Data System (ADS)

    Bernardez, Luis J., III; Siekhaus, W. J.

    1989-10-01

    Laser Ionization Mass Spectroscopy (LIMS) is a simple technique with several advantages and disadvantages over standard mass spectroscopy techniques. The LIMS technique uses a laser to vaporize a small portion of a sample. The vapor from the sample consists of a mixture of charged and neutral atoms or fragments. Using electrostatic grids, the ions (positive or negative) are given a known amount of kinetic energy and sent down a time-of-flight tube. The time it takes the ions to travel down the flight tube is recorded. Knowing the ions' energy, the length of the flight tube, and the time it takes the ions to travel that distance, the masses of the ions can be calculated. The instrument used is a LIMA 3 made by Cambridge Mass Spectrometry. It has a Quanta Ray DCR-11 Nd:YAG laser, which was frequency-quadrupled to 266 nm. The laser spot size is typically between 2 and 5 microns in diameter and the pulse width is between 5 and 10 nanoseconds. The energy of the laser is continually variable between 0.1 and 3.0 millijoules. The detector is a 17-stage venetian-blind multiplier made by Thorn EMI. The analysis is carried out under vacuum, usually between 10(exp -8) and 10(exp -9) Torr. The LIMA 3 has several useful features such as: a He-Ne pilot laser used to target the Nd:YAG laser; a microscope (which is used to view the sample through the laser optics); and a precision sample stage for accurate sample alignment.

  1. Laser ionization mass spectroscopy

    SciTech Connect

    Bernardez, L.J. III; Siekhaus, W.J. )

    1989-10-01

    Laser Ionization Mass Spectroscopy (LIMS) is a simple technique with several advantages and disadvantages over standard mass spectroscopy techniques. The LIMS technique uses a laser to vaporize a small portion of a sample. The vapor from the sample consists of a mixture of charged and neutral atoms or fragments. Using electrostatic grids, the ions (positive or negative) are given a known amount of kinetic energy and sent down a time-of-flight tube. The time it takes the ions to travel down the flight tube is recorded. Knowing the ions' energy, the length of the flight tube, and the time it takes the ions to travel that distance, the masses of the ions can be calculated. The instrument we use is a LIMA 3 made by Cambridge Mass Spectrometry. It has a Quanta Ray DCR-11 Nd:YAG laser, which we frequency-quadruple to 266 nm. The laser spot size is typically between 2 and 5 microns in diameter and the pulse width is between 5 and 10 nanoseconds. The energy of the laser is continually variable between 0.1 and 3.0 millijoules. The detector is a 17-stage venetian-blind multiplier made by Thorn EMI. The analysis is carried out under vacuum, usually between 10{sup {minus}8} and 10{sup {minus}9} Torr. The LIMA 3 has several useful features such as: a He-Ne pilot laser used to target the Nd:YAG laser; a microscope (which is used to view the sample through the laser optics); and a precision sample stage for accurate sample alignment. 6 figs., 1 tab.

  2. STOCHASTIC COOLING FOR BUNCHED BEAMS.

    SciTech Connect

    BLASKIEWICZ, M.

    2005-05-16

    Problems associated with bunched beam stochastic cooling are reviewed. A longitudinal stochastic cooling system for RHIC is under construction and has been partially commissioned. The state of the system and future plans are discussed.

  3. Electron Cooling of Bunched Beams

    SciTech Connect

    Uesugi, T.; Noda, K.; Syresin, E.; Meshkov, I.; Shibuya, S.

    2006-03-20

    Experiments of electron cooling have been done with the HIMAC synchrotron in NIRS. Limitation on cooled beam-sizes in longitudianl and transverse spaces were measured. The effect of space-charge field and intra-beam scattering are investigated.

  4. Maintaining gas cooling equipment

    SciTech Connect

    Rector, J.D.

    1997-05-01

    An often overlooked key to satisfactory operation and longevity of any mechanical device is proper operation and maintenance in accordance with the manufacturer`s written instructions. Absorption chillers, although they use a different technology than the more familiar vapor compression cycle to produce chilled water, operate successfully in a variety of applications if operated and maintained properly. Maintenance procedures may be more frequent than those required for vapor compression chillers, but they are also typically less complex. The goal of this article is to describe the basic operation of an absorption chiller to provide an understanding of the relatively simple tasks required to keep the machine operating at maximum efficiency for its design life and beyond. A good starting point is definitions. Gas cooling equipment is generally defined as alternative energy, non-electric cooling products. This includes absorption chillers, engine-drive chillers and packaged desiccant units, among others. Natural gas combustion drives the equipment.

  5. Cooling Floor AC Systems

    NASA Astrophysics Data System (ADS)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  6. Water Cooled Mirror Design

    SciTech Connect

    Dale, Gregory E.; Holloway, Michael Andrew; Pulliam, Elias Noel

    2015-03-30

    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  7. AIR COOLED NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Szilard, L.

    1958-05-27

    A nuclear reactor of the air-cooled, graphite moderated type is described. The active core consists of a cubicle mass of graphite, approximately 25 feet in each dimension, having horizontal channels of square cross section extending between two of the opposite faces, a plurality of cylindrical uranium slugs disposed in end to end abutting relationship within said channels providing a space in the channels through which air may be circulated, and a cadmium control rod extending within a channel provided in the moderator. Suitable shielding is provlded around the core, as are also provided a fuel element loading and discharge means, and a means to circulate air through the coolant channels through the fuel charels to cool the reactor.

  8. Radial turbine cooling

    NASA Technical Reports Server (NTRS)

    Roelke, Richard J.

    1992-01-01

    Radial turbines have been used extensively in many applications including small ground based electrical power generators, automotive engine turbochargers and aircraft auxiliary power units. In all of these applications the turbine inlet temperature is limited to a value commensurate with the material strength limitations and life requirements of uncooled metal rotors. To take advantage of all the benefits that higher temperatures offer, such as increased turbine specific power output or higher cycle thermal efficiency, requires improved high temperature materials and/or blade cooling. Extensive research is on-going to advance the material properties of high temperature superalloys as well as composite materials including ceramics. The use of ceramics with their high temperature potential and low cost is particularly appealing for radial turbines. However until these programs reach fruition the only way to make significant step increases beyond the present material temperature barriers is to cool the radial blading.

  9. Cooled particle accelerator target

    DOEpatents

    Degtiarenko, Pavel V.

    2005-06-14

    A novel particle beam target comprising: a rotating target disc mounted on a retainer and thermally coupled to a first array of spaced-apart parallel plate fins that extend radially inwardly from the retainer and mesh without physical contact with a second array of spaced-apart parallel plate fins that extend radially outwardly from and are thermally coupled to a cooling mechanism capable of removing heat from said second array of spaced-apart fins and located within the first array of spaced-apart parallel fins. Radiant thermal exchange between the two arrays of parallel plate fins provides removal of heat from the rotating disc. A method of cooling the rotating target is also described.

  10. COLD MOLECULAR GAS ALONG THE COOLING X-RAY FILAMENT IN A1795

    SciTech Connect

    McDonald, Michael; Wei, Lisa H.; Veilleux, Sylvain E-mail: lisa.wei@cfa.harvard.edu

    2012-08-20

    We present the results of interferometric observations of the cool core of A1795 at CO(1-0) using the Combined Array for Research in Millimeter-wave Astronomy. In agreement with previous work, we detect a significant amount of cold molecular gas (3.9 {+-} 0.4 Multiplication-Sign 10{sup 9} M{sub Sun }) in the central {approx}10 kpc. We report the discovery of a substantial clump of cold molecular gas at clustercentric radius of 30 kpc (2.9 {+-} 0.4 Multiplication-Sign 10{sup 9} M{sub Sun }), coincident in both position and velocity with the warm, ionized filaments. We also place an upper limit on the H{sub 2} mass at the outer edge of the star-forming filament, corresponding to a distance of 60 kpc (<0.9 Multiplication-Sign 10{sup 9} M{sub Sun }). We measure a strong gradient in the H{alpha}/H{sub 2} ratio as a function of radius, suggesting different ionization mechanisms in the nucleus and filaments of A1795. The total mass of cold molecular gas ({approx}7 Multiplication-Sign 10{sup 9} M{sub Sun }) is roughly 30% of the classical cooling estimate at the same position, assuming a cooling time of 10{sup 9} yr. Combining the cold molecular gas mass with the UV-derived star formation rate and the warm, ionized gas mass, the spectroscopically derived X-ray cooling rate is fully accounted for and in good agreement with the cooling byproducts over timescales of {approx}10{sup 9} yr. The overall agreement between the cooling rate of the hot intracluster medium and the mass of the cool gas reservoir suggests that, at least in this system, the cooling flow problem stems from a lack of observable cooling in the more diffuse regions at large radii.

  11. Vaporization Would Cool Primary Battery

    NASA Technical Reports Server (NTRS)

    Bhandari, Pradeep; Miyake, Robert N.

    1991-01-01

    Temperature of discharging high-power-density primary battery maintained below specified level by evaporation of suitable liquid from jacket surrounding battery, according to proposal. Pressure-relief valve regulates pressure and boiling temperature of liquid. Less material needed in cooling by vaporization than in cooling by melting. Technique used to cool batteries in situations in which engineering constraints on volume, mass, and location prevent attachment of cooling fins, heat pipes, or like.

  12. Computing Cooling Flows in Turbines

    NASA Technical Reports Server (NTRS)

    Gauntner, J.

    1986-01-01

    Algorithm developed for calculating both quantity of compressor bleed flow required to cool turbine and resulting decrease in efficiency due to cooling air injected into gas stream. Program intended for use with axial-flow, air-breathing, jet-propulsion engines with variety of airfoil-cooling configurations. Algorithm results compared extremely well with figures given by major engine manufacturers for given bulk-metal temperatures and cooling configurations. Program written in FORTRAN IV for batch execution.

  13. Cooled thin metal liner

    NASA Technical Reports Server (NTRS)

    Liang, George P. (Inventor)

    1995-01-01

    A first metal sheet (34) has openings (46) in registration with depressions (40) in a second contacting metal sheet (36). Each depression has a downstream wall (42) at an angle of 24.degree. from the plane of the sheets. A metering hole (56) in the depression amidst cooling air in a direction to first impinge against an overlaying portion (48) of the first plate, before it diffuses along the downstream wall.

  14. Cooling your home naturally

    SciTech Connect

    1994-10-01

    This fact sheet describes some alternatives to air conditioning which are common sense suggestions and low-cost retrofit options to cool a house. It first describes how to reflect heat away from roofs, walls, and windows. Blocking heat by using insulation or shading are described. The publication then discusses removing built-up heat, reducing heat-generating sources, and saving energy by selecting energy efficient retrofit appliances. A resource list is provided for further information.

  15. Conduction cooled tube supports

    DOEpatents

    Worley, Arthur C.; Becht, IV, Charles

    1984-01-01

    In boilers, process tubes are suspended by means of support studs that are in thermal contact with and attached to the metal roof casing of the boiler and the upper bend portions of the process tubes. The support studs are sufficiently short that when the boiler is in use, the support studs are cooled by conduction of heat to the process tubes and the roof casing thereby maintaining the temperature of the stud so that it does not exceed 1400.degree. F.

  16. Project S'COOL

    NASA Technical Reports Server (NTRS)

    Green, Carolyn J.; Chambers, Lin H.

    1998-01-01

    The Students Clouds Observations On-Line or S'COOL project was piloted in 1997. It was created with the idea of using students to serve as one component of the validation for the Clouds and the Earth's Radiant Energy System (CERES) instrument which was launched with the Tropical Rainfall Measuring Mission (TRMM) in November, 1997. As part of NASA's Earth Science Enterprise CERES is interested in the role clouds play in regulating our climate. Over thirty schools became involved in the initial thrust of the project. The CERES instrument detects the location of clouds and identifies their physical properties. S'COOL students coordinate their ground truth observations with the exact overpass of the satellite at their location. Their findings regarding cloud type, height, fraction and opacity as well as surface conditions are then reported to the NASA Langley Distributed Active Archive Center (DAAC). The data is then accessible to both the CERES team for validation and to schools for educational application via the Internet. By March of 1998 ninety-three schools, in nine countries had enrolled in the S'COOL project. Joining the United States participants were from schools in Australia, Canada, France, Germany, Norway, Spain, Sweden, and Switzerland. The project is gradually becoming the global project envisioned by the project s creators. As students obtain the requested data useful for the scientists, it was hoped that students with guidance from their instructors would have opportunity and motivation to learn more about clouds and atmospheric science as well.

  17. Cab Heating and Cooling

    SciTech Connect

    Damman, Dennis

    2005-10-31

    Schneider National, Inc., SNI, has concluded the Cab Heating and Cooling evaluation of onboard, engine off idling solutions. During the evaluation period three technologies were tested, a Webasto Airtronic diesel fired heater for cold weather operation, and two different approaches to cab cooling in warm weather, a Webasto Parking Cooler, phase change storage system and a Bergstrom Nite System, a 12 volt electrical air conditioning approach to cooling. Diesel fired cab heaters were concluded to provide adequate heat in winter environments down to 10 F. With a targeted idle reduction of 17%, the payback period is under 2 years. The Webasto Parking Cooler demonstrated the viability of this type of technology, but required significant driver involvement to achieve maximum performance. Drivers rated the technology as ''acceptable'', however, in individual discussions it became apparent they were not satisfied with the system limitations in hot weather, (over 85 F). The Bergstrom Nite system was recognized as an improvement by drivers and required less direct driver input to operate. While slightly improved over the Parking Cooler, the hot temperature limitations were only slightly better. Neither the Parking Cooler or the Nite System showed any payback potential at the targeted 17% idle reduction. Fleets who are starting at a higher idle baseline may have a more favorable payback.

  18. Water-Cooled Optical Thermometer

    NASA Technical Reports Server (NTRS)

    Menna, A. A.

    1987-01-01

    Water-cooled optical probe measures temperature of nearby radiating object. Intended primarily for use in silicon-growing furnace for measuring and controlling temperatures of silicon ribbon, meniscus, cartridge surfaces, heaters, or other parts. Cooling water and flushing gas cool fiber-optic probe and keep it clean. Fiber passes thermal radiation from observed surface to measuring instrument.

  19. Electron-impact ionization cross sections out of the ground and excited states of cesium

    SciTech Connect

    Lukomski, M.; Sutton, S.; Kedzierski, W.; Reddish, T. J.; Bartschat, K.; Bartlett, P. L.; Bray, I.; Stelbovics, A. T.; McConkey, J. W.

    2006-09-15

    An atom trapping technique for determining absolute, total ionization cross sections (TICS) out of an excited atom is presented. The unique feature of our method is in utilizing Doppler cooling of neutral atoms to determine ionization cross sections. This fluorescence-monitoring experiment, which is a variant of the 'trap loss' technique, has enabled us to obtain the experimental electron impact ionization cross sections out of the Cs state between 7 eV and 400 eV. CCC, RMPS, and Born theoretical results are also presented for both the ground and excited states of cesium and rubidium. In the low energy region (<11 eV) where best agreement between these excited state measurements and theory might be expected, a discrepancy of approximately a factor of five is observed. Above this energy there are significant contributions to the TICS from both autoionization and multiple ionization.

  20. Heating of the Warm Ionized Medium by Low-energy Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Walker, Mark A.

    2016-02-01

    In light of evidence for a high ionization rate due to low-energy cosmic rays (LECR) in diffuse molecular gas in the solar neighborhood, we evaluate their heat input to the warm ionized medium (WIM). LECR are much more effective at heating plasma than they are at heating neutrals. We show that the upper end of the measured ionization rates corresponds to a local LECR heating rate sufficient to maintain the WIM against radiative cooling, independent of the nature of the ionizing particles or the detailed shape of their spectrum. Elsewhere in the Galaxy the LECR heating rates may be higher than those measured locally. In particular, higher fluxes of LECR have been suggested for the inner Galactic disk, based on the observed hard X-ray emission, with correspondingly larger heating rates implied for the WIM. We conclude that LECR play an important and perhaps dominant role in the thermal balance of the WIM.

  1. Vibrational Cooling of Photoassociated Homonuclear Cold Molecules

    NASA Astrophysics Data System (ADS)

    Passagem, Henry; Ventura, Paulo; Tallant, Jonathan; Marcassa, Luis

    2015-05-01

    In this work, we produce vibrationally cold homonuclear Rb molecules using spontaneous optical pumping. The vibrationally cooled molecules are produced in three steps. In the first step, we use a photoassociation laser to produce molecules in high vibrational levels of the singlet ground state. Then in a second step, a 50 W broadband laser at 1071 nm, which bandwidth is about 2 nm, is used to transfer the molecules to lower vibrational levels via optical pumping through the excited state. This process transfers the molecules from vibrational levels around ν ~= 113 to a distribution of levels below ν = 35 . The molecules can be further cooled using a broadband light source near 685 nm. In order to obtain such broadband source, we have used a 5 mW superluminescent diode, which is amplified in a tapered amplifier using a double pass configuration. After the amplification, the spectrum is properly shaped and we end up with about 90 mW distributed in the 682-689 nm range. The final vibrational distribution is probed using resonance-enhanced multiphoton ionization with a pulsed dye laser near 670 nm operating at 4KHz. The results are presented and compared with theoretical simulations. This work was supported by Fapesp and INCT-IQ.

  2. Relative Raman Intensities in C6H6, C6D6, and C6F6: A Comparison of Different Computational Methods

    SciTech Connect

    Williams, Stephen D.; Johnson, Timothy J.; Gibbons, Thomas; Kitchens, Christopher L.

    2007-02-01

    In order to determine which models can best emulate Raman spectra, the accuracy of various computational methods (Hartee-Fock, MP2, CCSD, CAS-SCF, and several types of DFT) for predicting relative intensities in the Raman spectra of C6H6, C6D6, and C6F6 were compared. In particular, the predicted relative intensities for v1 and v2 were compared with relative intensities measured by an FT-Raman spectrometer. While none of these methods excelled at this prediction, Hartee-Fock with a large basis set was most successful for C6H6, and C6D6, while PW91PW91 with the aug-cc-pVTZ basis set was most successful for C6F6.

  3. Progress on Design and Construction of a MuCool Coupling Solenoid Magnet

    SciTech Connect

    Wang, L.; Liu, Xiao Kun; Xu, FengYu; Li, S.; Pan, Heng; Wu, Hong; Guo, Xinglong; Zheng, ShiXian; Li, Derun; Virostek, Steve; Zisman, Mike; Green, M.A.

    2010-06-28

    The MuCool program undertaken by the US Neutrino Factory and Muon Collider Collaboration is to study the behavior of muon ionization cooling channel components. A single superconducting coupling solenoid magnet is necessary to pursue the research and development work on the performance of high gradient, large size RF cavities immersed in magnetic field, which is one of the main challenges in the practical realization of ionization cooling of muons. The MuCool coupling magnet is to be built using commercial copper based niobium titanium conductors and cooled by two cryo-coolers with each cooling capacity of 1.5 W at 4.2 K. The solenoid magnet will be powered by using a single 300A power supply through a single pair of binary leads that are designed to carry a maximum current of 210A. The magnet is to be passively protected by cold diodes and resistors across sections of the coil and by quench back from the 6061 Al mandrel in order to lower the quench voltage and the hot spot temperature. The magnet is currently under construction. This paper presents the updated design and fabrication progress on the MuCool coupling magnet.

  4. Distinct lymphocyte antigens 6 (Ly6) family members Ly6D, Ly6E, Ly6K and Ly6H drive tumorigenesis and clinical outcome.

    PubMed

    Luo, Linlin; McGarvey, Peter; Madhavan, Subha; Kumar, Rakesh; Gusev, Yuriy; Upadhyay, Geeta

    2016-03-01

    Stem cell antigen-1 (Sca-1) is used to isolate and characterize tumor initiating cell populations from tumors of various murine models [1]. Sca-1 induced disruption of TGF-β signaling is required in vivo tumorigenesis in breast cancer models [2, 3-5]. The role of human Ly6 gene family is only beginning to be appreciated in recent literature [6-9]. To study the significance of Ly6 gene family members, we have visualized one hundred thirty gene expression omnibus (GEO) dataset using Oncomine (Invitrogen) and Georgetown Database of Cancer (G-DOC). This analysis showed that four different members Ly6D, Ly6E, Ly6H or Ly6K have increased gene expressed in bladder, brain and CNS, breast, colorectal, cervical, ovarian, lung, head and neck, pancreatic and prostate cancer than their normal counter part tissues. Increased expression of Ly6D, Ly6E, Ly6H or Ly6K was observed in sub-set of cancer type. The increased expression of Ly6D, Ly6E, Ly6H and Ly6K was found to be associated with poor outcome in ovarian, colorectal, gastric, breast, lung, bladder or brain and CNS as observed by KM plotter and PROGgeneV2 platform. The remarkable findings of increased expression of Ly6 family members and its positive correlation with poor outcome on patient survival in multiple cancer type indicate that Ly6 family members Ly6D, Ly6E, Ly6K and Ly6H will be an important targets in clinical practice as marker of poor prognosis and for developing novel therapeutics in multiple cancer type. PMID:26862846

  5. Distinct lymphocyte antigens 6 (Ly6) family members Ly6D, Ly6E, Ly6K and Ly6H drive tumorigenesis and clinical outcome

    PubMed Central

    Luo, Linlin; McGarvey, Peter; Madhavan, Subha; Kumar, Rakesh; Gusev, Yuriy; Upadhyay, Geeta

    2016-01-01

    Stem cell antigen-1 (Sca-1) is used to isolate and characterize tumor initiating cell populations from tumors of various murine models [1]. Sca-1 induced disruption of TGF-β signaling is required in vivo tumorigenesis in breast cancer models [2, 3-5]. The role of human Ly6 gene family is only beginning to be appreciated in recent literature [6-9]. To study the significance of Ly6 gene family members, we have visualized one hundred thirty gene expression omnibus (GEO) dataset using Oncomine (Invitrogen) and Georgetown Database of Cancer (G-DOC). This analysis showed that four different members Ly6D, Ly6E, Ly6H or Ly6K have increased gene expressed in bladder, brain and CNS, breast, colorectal, cervical, ovarian, lung, head and neck, pancreatic and prostate cancer than their normal counter part tissues. Increased expression of Ly6D, Ly6E, Ly6H or Ly6K was observed in sub-set of cancer type. The increased expression of Ly6D, Ly6E, Ly6H and Ly6K was found to be associated with poor outcome in ovarian, colorectal, gastric, breast, lung, bladder or brain and CNS as observed by KM plotter and PROGgeneV2 platform. The remarkable findings of increased expression of Ly6 family members and its positive correlation with poor outcome on patient survival in multiple cancer type indicate that Ly6 family members Ly6D, Ly6E, Ly6K and Ly6H will be an important targets in clinical practice as marker of poor prognosis and for developing novel therapeutics in multiple cancer type. PMID:26862846

  6. Synergy of the Developed 6D BIM Framework and Conception of the nD BIM Framework and nD BIM Process Ontology

    ERIC Educational Resources Information Center

    O'Keeffe, Shawn Edward

    2013-01-01

    The author developed a unified nD framework and process ontology for Building Information Modeling (BIM). The research includes a framework developed for 6D BIM, nD BIM, and nD ontology that defines the domain and sub-domain constructs for future nD BIM dimensions. The nD ontology defines the relationships of kinds within any new proposed…

  7. Laser cooling, trapping, and Rydberg spectroscopy of neutral holmium atoms

    NASA Astrophysics Data System (ADS)

    Hostetter, James Allen

    This thesis focuses on progress towards using ensembles of neutral holmium for use in quantum computing operations. We are particularly interested in using a switchable interaction between neutral atoms, the Rydberg blockade, to implement a universal set of quantum gates in a collective encoding scheme that presents many benefits over quantum computing schemes which rely on physically distinct qubits. We show that holmium is uniquely suited for operations in a collective encoding basis because it has 128 ground hyperfine states, the largest number of any stable, neutral atom. Holmium is a rare earth atom that is very poorly described for our purposes as it has never been cooled and trapped, its spectrum is largely unknown, and it presents several unique experimental challenges related to its complicated atomic structure and short wavelength transitions. We demonstrate important progress towards overcoming these challenges. We produce the first laser cooling and trapping of holmium into a MOT. Because we use a broad cooling transition, our cooling technique does not require the use of a Zeeman slower. Using MOT depletion spectroscopy, we provide precise measurements of holmium's Rydberg states and its ionization potential. Our work continues towards cooling holmium into a dipole trap by calculating holmium's AC polarizability and demonstrating the results of early attempts at an optical dipole trap. We provide details of future upgrades to the experimental apparatus and discuss interesting potential for using holmium in quantum computing using single atoms in a magnetically trapped lattice. This thesis shows several promising indicators for continued work in this field.

  8. Proposal for laser cooling of rare-earth ions

    NASA Astrophysics Data System (ADS)

    Dulieu, Olivier; Hong, Ye; Wyart, Jean-François; Lepers, Maxence

    2016-05-01

    The efficiency of laser cooling relies on the existence of an almost closed optical-transition cycle in the energy spectrum of the considered species. In this respect, rare-earth elements exhibit many transitions which are likely to induce noticeable leaks from the cooling cycle. In this work, to determine whether laser cooling of singly ionized erbium Er+ is feasible, we have performed accurate electronic-structure calculations of energies and spontaneous-emission Einstein coefficients of Er+, using a combination of ab initio and least-squares-fitting techniques. We identify five weak closed transitions suitable for laser cooling, the broadest of which is in the kilohertz range. For the strongest transitions, by simulating the cascade dynamics of spontaneous emission, we show that repumping is necessary, and we discuss possible repumping schemes.We expect our detailed study on Er+ to give good insight into the laser cooling of neighboring ions such as Dy+. Supported by ``Agence Nationale de la Recherche'' (ANR), under the project COPOMOL (Contract No. ANR-13-IS04-0004-01).

  9. Perinatal modification of a sexually dimorphic motor nucleus in the spinal cord of the B6D2F1 house mouse.

    PubMed

    Wagner, C K; Clemens, L G

    1989-04-01

    The sexually dimorphic dorsomedial nucleus (DM) of the spinal cord of mice is affected by gonadal steroids in adulthood and these effects are dependent upon genotype. Following castration of adult mice there is a decrease in DM cell size in DBA/2J and hybrid B6D2F1 strains and a decrease in the number of cells staining with thionin in C57B1/6J and B6D2F1 strains. The effects of androgens on development of the DM nucleus were examined in B6D2F1 mice, which exhibit both characteristics in adulthood. Testosterone propionate (TP) administered to females pre- or postnatally resulted in a significantly larger number of motoneurons in the region of the DM when compared to administration of the vehicle alone, while soma area remained unchanged. Adult males castrated on the day of birth had significantly fewer cells in the DM than did intact males. Differences in cell size between shams and castrates were dependent upon age. PMID:2780856

  10. Legionella in cooling towers.

    PubMed

    Witherell, L E; Novick, L F; Stone, K M; Duncan, R W; Orciari, L A; Kappel, S J; Jillson, D A

    1986-01-01

    Legionellosis (Legionnaires' disease and Pontiac fever) outbreaks have been associated with aerosols ejected from contaminated cooling towers--wet-type heat rejection units (WTHRUs) used to dissipate unwanted heat into the atmosphere. The Vermont Department of Health undertook a program to inventory, inspect, and sample all WTHRUs in Vermont from April 1981 to April 1982. All WTHRUs were sampled for Legionella pneumophila and data were obtained for location, design, construction, and operating characteristics. Of the 184 WTHRUs operating, statistical analyses were performed on those 130 which were sampled for L. pneumophila only once during the study period. Of these, 11 (8.5%) were positive for L. pneumophila. Sources of makeup water and period of operation had significant association with the recovery of L. pneumophila. Five out of 92 towers (5.4%) utilizing surface water sources for cooling were positive for L. pneumophila, in contrast to 6 positive towers of the 38 units (15.8%) which obtained makeup water from ground water sources (p = .054 by chi-square test). Nearly 15% of the 54 units which operated throughout the year were positive, compared to less than 4% of the 76 towers operating seasonally (p = .03 by chi-square test). The mean pH of the cooling water in units where L. pneumophila was recovered (8.3) was significantly higher than the mean pH of 7.9 in units testing negative (p less than .05 by t-test). In addition, the mean log-transformed turbidity of positive towers, 0.03 nephelometric units (ntu), was significantly lower than the mean of log turbidity of negative towers, 0.69 ntu (p less than .02 by t-test). PMID:10281778

  11. Cooled artery extension

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor)

    1990-01-01

    An artery vapor trap. A heat pipe artery is constructed with an extension protruding from the evaporator end of the heat pipe beyond the active area of the evaporator. The vapor migrates into the artery extension because of gravity or liquid displacement, and cooling the extension condenses the vapor to liquid, thus preventing vapor lock in the working portion of the artery by removing vapor from within the active artery. The condensed liquid is then transported back to the evaporator by the capillary action of the artery extension itself or by wick located within the extension.

  12. Heat pipe cooled probe

    NASA Technical Reports Server (NTRS)

    Camarda, C. J. (Inventor); Couch, L. M.

    1984-01-01

    The basic heat pipe principle is employed to provide a self-contained passively cooled probe that may be placed into a high temperature environment. The probe consists of an evaporator region of a heat pipe and a sensing instrument. Heat is absorbed as the working fluid evaporates in the probe. The vapor is transported to the vapor space of the condenser region. Heat is dissipated from the condenser region and fins causing condensation of the working fluid, which returns to the probe by gravity and the capillary action of the wick. Working fluid, wick and condenser configurations and structure materials can be selected to maintain the probe within an acceptable temperature range.

  13. Superconducting magnet cooling system

    DOEpatents

    Vander Arend, Peter C.; Fowler, William B.

    1977-01-01

    A device is provided for cooling a conductor to the superconducting state. The conductor is positioned within an inner conduit through which is flowing a supercooled liquid coolant in physical contact with the conductor. The inner conduit is positioned within an outer conduit so that an annular open space is formed therebetween. Through the annular space is flowing coolant in the boiling liquid state. Heat generated by the conductor is transferred by convection within the supercooled liquid coolant to the inner wall of the inner conduit and then is removed by the boiling liquid coolant, making the heat removal from the conductor relatively independent of conductor length.

  14. Turbine airfoil film cooling

    NASA Astrophysics Data System (ADS)

    Hylton, Larry D.

    1986-10-01

    Emphasis is placed on developing more accurate analytical models for predicting turbine airfoil external heat transfer rates. Performance goals of new engines require highly refined, accurate design tools to meet durability requirements. In order to obtain improvements in analytical capabilities, programs are required which focus on enhancing analytical techniques through verification of new models by comparison with relevant experimental data. The objectives of the current program are to develop an analytical approach, based on boundary layer theory, for predicting the effects of airfoil film cooling on downstream heat transfer rates and to verify the resulting analytical method by comparison of predictions with hot cascade data obtained under this program.

  15. Cooled, temperature controlled electrometer

    DOEpatents

    Morgan, John P.

    1992-08-04

    A cooled, temperature controlled electrometer for the measurement of small currents. The device employs a thermal transfer system to remove heat from the electrometer circuit and its environment and dissipate it to the external environment by means of a heat sink. The operation of the thermal transfer system is governed by a temperature regulation circuit which activates the thermal transfer system when the temperature of the electrometer circuit and its environment exceeds a level previously inputted to the external variable temperature control circuit. The variable temperature control circuit functions as subpart of the temperature control circuit. To provide temperature stability and uniformity, the electrometer circuit is enclosed by an insulated housing.

  16. Cooled, temperature controlled electrometer

    DOEpatents

    Morgan, John P.

    1992-01-01

    A cooled, temperature controlled electrometer for the measurement of small currents. The device employs a thermal transfer system to remove heat from the electrometer circuit and its environment and dissipate it to the external environment by means of a heat sink. The operation of the thermal transfer system is governed by a temperature regulation circuit which activates the thermal transfer system when the temperature of the electrometer circuit and its environment exceeds a level previously inputted to the external variable temperature control circuit. The variable temperature control circuit functions as subpart of the temperature control circuit. To provide temperature stability and uniformity, the electrometer circuit is enclosed by an insulated housing.

  17. Rotary engine cooling system

    NASA Technical Reports Server (NTRS)

    Jones, Charles (Inventor); Gigon, Richard M. (Inventor); Blum, Edward J. (Inventor)

    1985-01-01

    A rotary engine has a substantially trochoidal-shaped housing cavity in which a rotor planetates. A cooling system for the engine directs coolant along a single series path consisting of series connected groups of passages. Coolant enters near the intake port, passes downwardly and axially through the cooler regions of the engine, then passes upwardly and axially through the hotter regions. By first flowing through the coolest regions, coolant pressure is reduced, thus reducing the saturation temperature of the coolant and thereby enhancing the nucleate boiling heat transfer mechanism which predominates in the high heat flux region of the engine during high power level operation.

  18. Cooling apparatus and method

    DOEpatents

    Mayes, James C.

    2009-05-05

    A device and method provide for cooling of a system having an energy source, one or more devices that actively consume energy, and one or more devices that generate heat. The device may include one or more thermoelectric coolers ("TECs") in conductive engagement with at least one of the heat-generating devices, and an energy diverter for diverting at least a portion of the energy from the energy source that is not consumed by the active energy-consuming devices to the TECs.

  19. Supersonic jet/multiphoton ionization spectrometry of chemical species resulting from thermal decomposition and laser ablation of polymers

    NASA Astrophysics Data System (ADS)

    Hozumi, Masami; Murata, Yoshiaki; Cheng-Huang Lin, Imasaka, Totaro

    1995-04-01

    The chemical species resulting from thermal decomposition and laser ablation of polymers are measured by excitation/fluorescence and multiphoton ionization/mass spectrometries after supersonic jet expansion for rotational cooling to simply the optical spectrum. The signal of minor chemical species occurred is strongly enhanced by resonant excitation and multiphoton ionization, and even the isomer can be clearly differentiated. For example, p-cresol occurred by thermal decomposition of polycarbonate is detected selectively by mass-selected resonant multiphoton ionization spectrometry. Various chemical species occurred by laser ablation of even a polystyrene foam are also measured by this technique.

  20. Emergency core cooling system

    DOEpatents

    Schenewerk, William E.; Glasgow, Lyle E.

    1983-01-01

    A liquid metal cooled fast breeder reactor provided with an emergency core cooling system includes a reactor vessel which contains a reactor core comprising an array of fuel assemblies and a plurality of blanket assemblies. The reactor core is immersed in a pool of liquid metal coolant. The reactor also includes a primary coolant system comprising a pump and conduits for circulating liquid metal coolant to the reactor core and through the fuel and blanket assemblies of the core. A converging-diverging venturi nozzle with an intermediate throat section is provided in between the assemblies and the pump. The intermediate throat section of the nozzle is provided with at least one opening which is in fluid communication with the pool of liquid sodium. In normal operation, coolant flows from the pump through the nozzle to the assemblies with very little fluid flowing through the opening in the throat. However, when the pump is not running, residual heat in the core causes fluid from the pool to flow through the opening in the throat of the nozzle and outwardly through the nozzle to the assemblies, thus providing a means of removing decay heat.

  1. Cooled spool piston compressor

    NASA Technical Reports Server (NTRS)

    Morris, Brian G. (Inventor)

    1993-01-01

    A hydraulically powered gas compressor receives low pressure gas and outputs a high pressure gas. The housing of the compressor defines a cylinder with a center chamber having a cross-sectional area less than the cross-sectional area of a left end chamber and a right end chamber, and a spool-type piston assembly is movable within the cylinder and includes a left end closure, a right end closure, and a center body that are in sealing engagement with the respective cylinder walls as the piston reciprocates. First and second annual compression chambers are provided between the piston enclosures and center housing portion of the compressor, thereby minimizing the spacing between the core gas and a cooled surface of the compressor. Restricted flow passageways are provided in the piston closure members and a path is provided in the central body of the piston assembly, such that hydraulic fluid flows through the piston assembly to cool the piston assembly during its operation. The compressor of the present invention may be easily adapted for a particular application, and is capable of generating high gas pressures while maintaining both the compressed gas and the compressor components within acceptable temperature limits.

  2. Cooling of dried coal

    SciTech Connect

    Siddoway, M.A.

    1988-06-14

    This patent describes a process for noncombustibly drying particulate coal comprising: separating the coal into two wet coal streams; passing one wet coal system into a dryer to form a bed; heating air in a furnace; admitting the heated air to the dryer to fluidize the bed; withdrawing dryer exhaust gas; passing the exhaust gas through a cyclone and withdrawing coal fines from the cyclone; withdrawing a hot, dry coal stream from the dryer; blending the drier hot dry coal stream with the cyclone coal fines; withdrawing cyclone exhaust gas; wet scrubbing the cyclone exhaust gas to form a coal fines slurry and scrubber exhaust gas; passing the coal fines slurry to a sedimentation pool; blending the second wet coal stream with the drier hot dry coal stream and the cyclone coal fines; passing the latter blended stream to a cooler to form a bed; fluidizing the latter bed with ambient air; withdrawing cooler exhaust gas and passing the gas to a cyclone; passing exhaust gas from the latter cyclone to a baghouse and collecting coal fines therein; passing the latter coal fines to the furnace as fuel for heating the air; and withdrawing cooled coal from the cooler and blending the cooled coal with coal fines from the latter cyclone.

  3. ASTROMAG coil cooling study

    NASA Technical Reports Server (NTRS)

    Maytal, Ben-Zion; Vansciver, Steven W.

    1990-01-01

    ASTROMAG is a planned particle astrophysics magnetic facility. Basically it is a large magnetic spectrometer outside the Earth's atmosphere for an extended period of time in orbit on a space station. A definition team summarized its scientific objectives assumably related to fundamental questions of astrophysics, cosmology, and elementary particle physics. Since magnetic induction of about 7 Tesla is desired, it is planned to be a superconducting magnet cooled to liquid helium 2 temperatures. The general structure of ASTROMAG is based on: (1) two superconducting magnetic coils, (2) dewar of liquid helium 2 to provide cooling capability for the magnets; (3) instrumentation, matter-anti matter spectrometer (MAS) and cosmic ray isotope spectrometer (CRIS); and (4) interfaces to the shuttle and space station. Many configurations of the superconducting magnets and the dewar were proposed and evaluated, since those are the heart of the ASTROMAG. Baseline of the magnet configuration and cryostat as presented in the phase A study and the one kept in mind while doing the present study are presented. ASTROMAG's development schedule reflects the plan of launching to the space station in 1995.

  4. The Cool Kids Coalition.

    PubMed

    Corrarino, J E; Walsh, P J; Boyle, M L; Anselmo, D

    2000-01-01

    The Cool Kids Coalition was initiated as a community response to more than 214 hospitalizations of children under the age of five for burns over a 6-year period in one township in Long Island, NY. The coalition was started by public health nurses in partnership with the local chapter of the National Safe Kids Campaign. Goals included: 1. parent education regarding scald burn prevention; 2. development of innovative interventions for those at risk; and 3, development of innovative community approaches to scald prevention. Coalition members had diverse backgrounds and the coalition integrated non-traditional partners in injury control. The coalition doubled in size due to overwhelming community interest, growing within a few months from an initial group of 15 to a well-represented group of 30. Innovative programs were implemented that reached more than 3,000 parents, both in the community and home. Teaching was conducted with parents in the target population in Head Start centers, homeless shelters, the home, libraries, child care centers, a shelter for teen parents, etc. Member agencies incorporated the booklet and materials into their individual programs. The development of the Cool Kids Coalition illustrates the power of nursing in community health. PMID:10676080

  5. State Machine Operation of the MICE Cooling Channel

    NASA Astrophysics Data System (ADS)

    Hanlet, Pierrick; Mice Collaboration

    2014-06-01

    The Muon Ionization Cooling Experiment (MICE) is a demonstration experiment to prove the feasibility of cooling a beam of muons for use in a Neutrino Factory and/or Muon Collider. The MICE cooling channel is a section of a modified Study II cooling channel which will provide a 10% reduction in beam emittance. In order to ensure a reliable measurement, MICE will measure the beam emittance before and after the cooling channel at the level of 1%, a relative measurement of 0.001. This renders MICE a precision experiment which requires strict controls and monitoring of all experimental parameters in order to control systematic errors. The MICE Controls and Monitoring system is based on EPICS and integrates with the DAQ, Data monitoring systems, and a configuration database. The cooling channel for MICE has between 12 and 18 superconductnig solenoid coils in 3 to 7 magnets, depending on the staged development of the experiment. The magnets are coaxial and in close proximity which requires coordinated operation of the magnets when ramping, responding to quench conditions, and quench recovery. To reliably manage the operation of the magnets, MICE is implementing state machines for each magnet and an over-arching state machine for the magnets integrated in the cooling channel. The state machine transitions and operating parameters are stored/restored to/from the configuration database and coupled with MICE Run Control. Proper implementation of the state machines will not only ensure safe operation of the magnets, but will help ensure reliable data quality. A description of MICE, details of the state machines, and lessons learned from use of the state machines in recent magnet training tests will be discussed.

  6. NightCool: A Nocturnal Radiation Cooling Concept

    SciTech Connect

    Parker, Danny S.; Sherwin, John R.; Hermelink, Andreas H.

    2008-08-26

    This report describes an experimental evaluation that was conducted on a night sky cooling system designed to substantially reduce space cooling needs in homes in North American climates. The system uses a sealed attic covered by a highly conductive metal roof (a roof integrated radiator) which is selectively linked by air flow to the main zone with the attic zone to provide cooling - largely during nighttime hours.

  7. The Cool Flames Experiment

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Chapek, Richard; Neville, Donna; Sheredy, William; Wu, Ming-Shin; Tornabene, Robert

    2001-01-01

    A space-based experiment is currently under development to study diffusion-controlled, gas-phase, low temperature oxidation reactions, cool flames and auto-ignition in an unstirred, static reactor. At Earth's gravity (1g), natural convection due to self-heating during the course of slow reaction dominates diffusive transport and produces spatio-temporal variations in the thermal and thus species concentration profiles via the Arrhenius temperature dependence of the reaction rates. Natural convection is important in all terrestrial cool flame and auto-ignition studies, except for select low pressure, highly dilute (small temperature excess) studies in small vessels (i.e., small Rayleigh number). On Earth, natural convection occurs when the Rayleigh number (Ra) exceeds a critical value of approximately 600. Typical values of the Ra, associated with cool flames and auto-ignitions, range from 104-105 (or larger), a regime where both natural convection and conduction heat transport are important. When natural convection occurs, it alters the temperature, hydrodynamic, and species concentration fields, thus generating a multi-dimensional field that is extremely difficult, if not impossible, to be modeled analytically. This point has been emphasized recently by Kagan and co-workers who have shown that explosion limits can shift depending on the characteristic length scale associated with the natural convection. Moreover, natural convection in unstirred reactors is never "sufficiently strong to generate a spatially uniform temperature distribution throughout the reacting gas." Thus, an unstirred, nonisothermal reaction on Earth does not reduce to that generated in a mechanically, well-stirred system. Interestingly, however, thermal ignition theories and thermokinetic models neglect natural convection and assume a heat transfer correlation of the form: q=h(S/V)(T(bar) - Tw) where q is the heat loss per unit volume, h is the heat transfer coefficient, S/V is the surface to

  8. Microwave ionization of Rydberg atoms

    SciTech Connect

    Gallagher, T.F.

    1996-12-31

    An atom can be ionized by a static field if the field depresses the potential below the binding energy W, leading to the requirement E = W{sup 2}/4 in atomic units. The atomic units of field and energy are 5.14 {times} 10{sup 9} V/cm and 27.2 eV. The ionization field is often expressed in terms of the principal quantum number n of the state in question as E = 1/16n{sup 4}. In a microwave field with frequency far less than the separation {Delta}W = 1/n{sup 3} between adjacent n states, atoms other than H ionize at the much lower microwave field amplitude of E = 1/3n{sup 5}. This field corresponds to the Inglis-Teller limit, where it is impossible to resolve spectrally adjacent n states due to Stark broadening in a plasma. In H ionization occurs as it does in a static field. The difference exists because the finite sized ionic core of a non hydrogenic atom breaks one of the symmetries found in H. In non hydrogenic atoms the microwave field drives a series of transitions through successively higher n states culminating in ionization. These transitions can be understood in terms of a Landau-Zener picture based on the variation of the energies of the atoms produced by the time varying field or as the resonant multiphoton absorption of the microwave photons. In either case, the atoms make transitions through real intermediate states en route to ionization. With short, four cycle, microwave pulses complete ionization does not occur with fields of E = 1/3n{sup 5}, and population is left in intermediate states. The transition from ionization at fields near E = 1/3n{sup 5} to fields of E = 1/16n{sup 4} occurs when the frequency becomes low enough that the energies of the states vary adiabatically in the temporally varying field.

  9. Indirect passive cooling system for liquid metal cooled nuclear reactors

    DOEpatents

    Hunsbedt, Anstein; Boardman, Charles E.

    1990-01-01

    A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

  10. THE COOLING OF CORONAL PLASMAS. IV. CATASTROPHIC COOLING OF LOOPS

    SciTech Connect

    Cargill, P. J.; Bradshaw, S. J.

    2013-07-20

    We examine the radiative cooling of coronal loops and demonstrate that the recently identified catastrophic cooling is due to the inability of a loop to sustain radiative/enthalpy cooling below a critical temperature, which can be >1 MK in flares, 0.5-1 MK in active regions, and 0.1 MK in long tenuous loops. Catastrophic cooling is characterized by a rapid fall in coronal temperature, while the coronal density changes by a small amount. Analytic expressions for the critical temperature are derived and show good agreement with numerical results. This effect considerably limits the lifetime of coronal plasmas below the critical temperature.

  11. Passive cooling safety system for liquid metal cooled nuclear reactors

    DOEpatents

    Hunsbedt, Anstein; Boardman, Charles E.; Hui, Marvin M.; Berglund, Robert C.

    1991-01-01

    A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

  12. Characteristics of low-temperature plasma ionization for ambient mass spectrometry compared to electrospray ionization and atmospheric pressure chemical ionization.

    PubMed

    Albert, Anastasia; Engelhard, Carsten

    2012-12-18

    Ambient desorption/ionization mass spectrometry (ADI-MS) is an attractive method for direct analysis with applications in homeland security, forensics, and human health. For example, low-temperature plasma probe (LTP) ionization was successfully used to detect, e.g., explosives, drugs, and pesticides directly on the target. Despite the fact that the field is gaining significant attention, few attempts have been made to classify ambient ionization techniques based on their ionization characteristics and performance compared to conventional ionization sources used in mass spectrometry. In the present study, relative ionization efficiencies (RIEs) for a large group of compound families were determined with LTP-Orbitrap-MS and compared to those obtained with electrospray ionization mass spectrometry (ESI-MS) and atmospheric pressure chemical ionization mass spectrometry (APCI-MS). RIEs were normalized against one reference compound used across all methods to ensure comparability of the results. Typically, LTP analyte ionization through protonation/deprotonation (e.g., 4-acetamidophenol) was observed; in some cases (e.g., acenaphthene) radicals were formed. Amines, amides, and aldehydes were ionized successfully with LTP. A benefit of LTP over conventional methods is the possibility to successfully ionize PAHs and imides. Here, the studied model compounds could be detected by neither APCI nor ESI. LTP is a relatively soft ionization method because little fragmentation of model compounds was observed. It is considered to be an attractive method for the ionization of low molecular weight compounds over a relatively wide polarity range. PMID:23134531

  13. Electronic cooling using thermoelectric devices

    SciTech Connect

    Zebarjadi, M.

    2015-05-18

    Thermoelectric coolers or Peltier coolers are used to pump heat in the opposite direction of the natural heat flux. These coolers have also been proposed for electronic cooling, wherein the aim is to pump heat in the natural heat flux direction and from hot spots to the colder ambient temperature. In this manuscript, we show that for such applications, one needs to use thermoelectric materials with large thermal conductivity and large power factor, instead of the traditionally used high ZT thermoelectric materials. We further show that with the known thermoelectric materials, the active cooling cannot compete with passive cooling, and one needs to explore a new set of materials to provide a cooling solution better than a regular copper heat sink. We propose a set of materials and directions for exploring possible materials candidates suitable for electronic cooling. Finally, to achieve maximum cooling, we propose to use thermoelectric elements as fins attached to copper blocks.

  14. Microscale technology electronics cooling overview

    NASA Astrophysics Data System (ADS)

    Golliher, Eric L.

    2002-01-01

    NASA requirements and subsequent technology solutions for high heat flux electronics are generally different that those for the terrestrial applications. Unlike terrestrial operations. NASA spacecraft have limited opportunities for air cooling, for example, and must rely on less efficient thermal radiation to reject heat to space. The terrestrial commercial electronics industry, as well as other Government agencies, is investing in advanced technologies for electronics cooling at the microscale. This paper gives a brief summary of metrics used in high heat flux electronics cooling, the difference between solutions developed for terrestrial requirements and those for space, and a short description of challenges as well as possible solutions for space-based high heat flux electronics cooling. The argument is made that high heat flux electronics cooling is indeed a core technology required by NASA, since the thermal and other environmental requirements are unique to NASA space missions and are not addressed by current terrestrial electronics cooling technology development projects. .

  15. Electronic cooling using thermoelectric devices

    NASA Astrophysics Data System (ADS)

    Zebarjadi, M.

    2015-05-01

    Thermoelectric coolers or Peltier coolers are used to pump heat in the opposite direction of the natural heat flux. These coolers have also been proposed for electronic cooling, wherein the aim is to pump heat in the natural heat flux direction and from hot spots to the colder ambient temperature. In this manuscript, we show that for such applications, one needs to use thermoelectric materials with large thermal conductivity and large power factor, instead of the traditionally used high ZT thermoelectric materials. We further show that with the known thermoelectric materials, the active cooling cannot compete with passive cooling, and one needs to explore a new set of materials to provide a cooling solution better than a regular copper heat sink. We propose a set of materials and directions for exploring possible materials candidates suitable for electronic cooling. Finally, to achieve maximum cooling, we propose to use thermoelectric elements as fins attached to copper blocks.

  16. Ionization of Water Clusters is Mediated by Exciton Energy Transfer from Argon Clusters

    SciTech Connect

    Golan, Amir; Ahmed, Musahid

    2012-01-25

    The exciton energy deposited in an argon cluster, (Arn ,< n=20>) using VUV radiation is transferred to softly ionize doped water clusters, ((H2O)n, n=1-9) leading to the formation of non-fragmented clusters. Following the initial excitation, electronic energy is channeled to ionize the doped water cluster while evaporating the Ar shell, allowing identification of fragmented and complete water cluster ions. Examination of the photoionization efficiency curve shows that cluster evaporation from excitons located above 12.6 eV are not enough to cool the energized water cluster ion, and leads to their dissociation to (H2O)n-2H+ (protonated) clusters.

  17. Multiphoton ionization/dissociation of cyclopentanone at the lower Rydberg states

    NASA Astrophysics Data System (ADS)

    Philis, John G.; Kosmidis, Constantine; Tzallas, Paraskevas

    1998-12-01

    The 2-photon excitation of the 3p and 3d Rydberg states in jet-cooled cyclopentanone has been investigated by resonance enhanced multiphoton ionization (REMPI) in a time of flight mass spectrometer. The three 3px,y,z components are clearly resolved while the case for the 3di excitations is obscure due to the S1 one-photon resonance. The ns laser induced mass spectra are characteristic of hard ionization while the fs laser induced mass spectrum is very similar to the Electron Impact one.

  18. Liquid cooling of aircraft engines

    NASA Technical Reports Server (NTRS)

    Weidinger, Hanns

    1931-01-01

    This report presents a method for solving the problem of liquid cooling at high temperatures, which is an intermediate method between water and air cooling, by experiments on a test-stand and on an airplane. A utilizable cooling medium was found in ethylene glycol, which has only one disadvantage, namely, that of combustibility. The danger, however is very slight. It has one decided advantage, that it simultaneously serves as protection against freezing.

  19. Stochastic cooling technology at Fermilab

    NASA Astrophysics Data System (ADS)

    Pasquinelli, Ralph J.

    2004-10-01

    The first antiproton cooling systems were installed and commissioned at Fermilab in 1984-1985. In the interim period, there have been several major upgrades, system improvements, and complete reincarnation of cooling systems. This paper will present some of the technology that was pioneered at Fermilab to implement stochastic cooling systems in both the Antiproton Source and Recycler accelerators. Current performance data will also be presented.

  20. Regeneratively Cooled Porous Media Jacket

    NASA Technical Reports Server (NTRS)

    Mungas, Greg (Inventor); Fisher, David J. (Inventor); London, Adam Pollok (Inventor); Fryer, Jack Merrill (Inventor)

    2013-01-01

    The fluid and heat transfer theory for regenerative cooling of a rocket combustion chamber with a porous media coolant jacket is presented. This model is used to design a regeneratively cooled rocket or other high temperature engine cooling jacket. Cooling jackets comprising impermeable inner and outer walls, and porous media channels are disclosed. Also disclosed are porous media coolant jackets with additional structures designed to transfer heat directly from the inner wall to the outer wall, and structures designed to direct movement of the coolant fluid from the inner wall to the outer wall. Methods of making such jackets are also disclosed.

  1. Three-dimensional laser cooling

    SciTech Connect

    Okamoto, Hiromi; Sessler, A.M.; Moehl, D.

    1994-06-01

    To realize effective transverse laser cooling simultaneously with longitudinal laser cooling, two possibilities are theoretically studied. The schemes are both based on forced synchro-betatron coupling, which transfer the extremely effective longitudinal laser cooling action to transverse directions. The coupling is provided by an rf-cavity with a transverse variation of the longitudinal electric field (e.g. TM{sub 210} mode) or by a normal rf-cavity located at a position of finite dispersion. It is shown that, when a working point is close to the difference resonance, cooling in all three degrees of freedom is simultaneously obtained.

  2. Stochastic Cooling Developments at GSI

    SciTech Connect

    Nolden, F.; Beckert, K.; Beller, P.; Dolinskii, A.; Franzke, B.; Jandewerth, U.; Nesmiyan, I.; Peschke, C.; Petri, P.; Steck, M.; Caspers, F.; Moehl, D.; Thorndahl, L.

    2006-03-20

    Stochastic Cooling is presently used at the existing storage ring ESR as a first stage of cooling for secondary heavy ion beams. In the frame of the FAIR project at GSI, stochastic cooling is planned to play a major role for the preparation of high quality antiproton and rare isotope beams. The paper describes the existing ESR system, the first stage cooling system at the planned Collector Ring, and will also cover first steps toward the design of an antiproton collection system at the planned RESR ring.

  3. Direct cooled power electronics substrate

    DOEpatents

    Wiles, Randy H [Powell, TN; Wereszczak, Andrew A [Oak Ridge, TN; Ayers, Curtis W [Kingston, TN; Lowe, Kirk T [Knoxville, TN

    2010-09-14

    The disclosure describes directly cooling a three-dimensional, direct metallization (DM) layer in a power electronics device. To enable sufficient cooling, coolant flow channels are formed within the ceramic substrate. The direct metallization layer (typically copper) may be bonded to the ceramic substrate, and semiconductor chips (such as IGBT and diodes) may be soldered or sintered onto the direct metallization layer to form a power electronics module. Multiple modules may be attached to cooling headers that provide in-flow and out-flow of coolant through the channels in the ceramic substrate. The modules and cooling header assembly are preferably sized to fit inside the core of a toroidal shaped capacitor.

  4. Thermoelectrically cooled water trap

    DOEpatents

    Micheels, Ronald H.

    2006-02-21

    A water trap system based on a thermoelectric cooling device is employed to remove a major fraction of the water from air samples, prior to analysis of these samples for chemical composition, by a variety of analytical techniques where water vapor interferes with the measurement process. These analytical techniques include infrared spectroscopy, mass spectrometry, ion mobility spectrometry and gas chromatography. The thermoelectric system for trapping water present in air samples can substantially improve detection sensitivity in these analytical techniques when it is necessary to measure trace analytes with concentrations in the ppm (parts per million) or ppb (parts per billion) partial pressure range. The thermoelectric trap design is compact and amenable to use in a portable gas monitoring instrumentation.

  5. Naturally cooled Florida house

    SciTech Connect

    Not Available

    1981-07-01

    A 1750 ft/sup 2/ home in northern Florida is described, constructed at a cost of $35/ft/sup 2/ (comparable to conventional homes), yet incorporating a number of passive solar and active systems. The well-planned design (emphasizing cooling rather than heating) is explained and illustrated in some detail. Notable features described include: (1) earth burning; (2) south facing greenhouse-solarium; (3) hatch-equipped attic wells which admit light and let the heat out; (4) roof overhangs above skylights; (5) solar screening over the greenhouse windows; (6) insulated drapes; (7) thermal insulation at R-28; (8) use of post-tensioned concrete (floor slab and walls); and (9) 2'' styrofoam skirting extending eight feet into the bermed earth. Use of engineering known-how to cut costs is discussed. (MJJ)

  6. Fluid cooled electrical assembly

    SciTech Connect

    Rinehart, Lawrence E.; Romero, Guillermo L.

    2007-02-06

    A heat producing, fluid cooled assembly that includes a housing made of liquid-impermeable material, which defines a fluid inlet and a fluid outlet and an opening. Also included is an electrical package having a set of semiconductor electrical devices supported on a substrate and the second major surface is a heat sink adapted to express heat generated from the electrical apparatus and wherein the second major surface defines a rim that is fit to the opening. Further, the housing is constructed so that as fluid travels from the fluid inlet to the fluid outlet it is constrained to flow past the opening thereby placing the fluid in contact with the heat sink.

  7. GAS COOLED NUCLEAR REACTORS

    DOEpatents

    Long, E.; Rodwell, W.

    1958-06-10

    A gas-cooled nuclear reactor consisting of a graphite reacting core and reflector structure supported in a containing vessel is described. A gas sealing means is included for sealing between the walls of the graphite structure and containing vessel to prevent the gas coolant by-passing the reacting core. The reacting core is a multi-sided right prismatic structure having a pair of parallel slots around its periphery. The containing vessel is cylindrical and has a rib on its internal surface which supports two continuous ring shaped flexible web members with their radially innermost ends in sealing engagement within the radially outermost portion of the slots. The core structure is supported on ball bearings. This design permits thermal expansion of the core stracture and vessel while maintainirg a peripheral seal between the tvo elements.

  8. High-resolution ionization detector and array of such detectors

    DOEpatents

    McGregor, Douglas S.; Rojeski, Ronald A.

    2001-01-16

    A high-resolution ionization detector and an array of such detectors are described which utilize a reference pattern of conductive or semiconductive material to form interaction, pervious and measurement regions in an ionization substrate of, for example, CdZnTe material. The ionization detector is a room temperature semiconductor radiation detector. Various geometries of such a detector and an array of such detectors produce room temperature operated gamma ray spectrometers with relatively high resolution. For example, a 1 cm.sup.3 detector is capable of measuring .sup.137 Cs 662 keV gamma rays with room temperature energy resolution approaching 2% at FWHM. Two major types of such detectors include a parallel strip semiconductor Frisch grid detector and the geometrically weighted trapezoid prism semiconductor Frisch grid detector. The geometrically weighted detector records room temperature (24.degree. C.) energy resolutions of 2.68% FWHM for .sup.137 Cs 662 keV gamma rays and 2.45% FWHM for .sup.60 Co 1.332 MeV gamma rays. The detectors perform well without any electronic pulse rejection, correction or compensation techniques. The devices operate at room temperature with simple commercially available NIM bin electronics and do not require special preamplifiers or cooling stages for good spectroscopic results.

  9. Fast ionized X-ray absorbers in AGNs

    NASA Astrophysics Data System (ADS)

    Fukumura, K.; Tombesi, F.; Kazanas, D.; Shrader, C.; Behar, E.; Contopoulos, I.

    2016-05-01

    We investigate the physics of the X-ray ionized absorbers often identified as warm absorbers (WAs) and ultra-fast outflows (UFOs) in Seyfert AGNs from spectroscopic studies in the context of magnetically-driven accretion-disk wind scenario. Launched and accelerated by the action of a global magnetic field anchored to an underlying accretion disk around a black hole, outflowing plasma is irradiated and ionized by an AGN radiation field characterized by its spectral energy density (SED). By numerically solving the Grad-Shafranov equation in the magnetohydrodynamic (MHD) framework, the physical property of the magnetized disk-wind is determined by a wind parameter set, which is then incorporated into radiative transfer calculations with xstar photoionization code under heating-cooling equilibrium state to compute the absorber's properties such as column density N_H, line-of-sight (LoS) velocity v, ionization parameter ξ, among others. Assuming that the wind density scales as n ∝ r-1, we calculate theoretical absorption measure distribution (AMD) for various ions seen in AGNs as well as line spectra especially for the Fe Kα absorption feature by focusing on a bright quasar PG 1211+143 as a case study and show the model's plausibility. In this note we demonstrate that the proposed MHD-driven disk-wind scenario is not only consistent with the observed X-ray data, but also help better constrain the underlying nature of the AGN environment in a close proximity to a central engine.

  10. Chemical protection against ionizing radiation

    NASA Astrophysics Data System (ADS)

    Maisin, J. R.

    Some of the problems related to chemical protection against ionizing radiation are discussed with emphasis on : definition, classification, degree of protection, mechanisms of action and toxicity. Results on the biological response modifyers (BRMs) and on the combination of nontoxic (i.e. low) doses of sulphydryl radioprotectors and BRMs are presented.

  11. Ionization Potentials for Isoelectronic Series.

    ERIC Educational Resources Information Center

    Agmon, Noam

    1988-01-01

    Presents a quantitative treatment of ionization potentials of isoelectronic atoms. By looking at the single-electron view of calculating the total energy of an atom, trends in the screening and effective quantum number parameters are examined. Approaches the question of determining electron affinities. (CW)

  12. Air cooled absorption chillers for solar cooling applications

    NASA Astrophysics Data System (ADS)

    Biermann, W. J.; Reimann, R. C.

    1982-03-01

    The chemical composition of a 'best' absorption refrigerant system is identified, and those properties of the system necessary to design hot water operated, air cooled chilling equipment are determined. Air cooled chillers from single family residential sizes into the commercial rooftop size range are designed and operated.

  13. FIELD INVESTIGATION OF COOLING TOWER AND COOLING POND PLUMES

    EPA Science Inventory

    Measurements were made relating to the behavior of water-vapor plumes from forced-draft cooling towers and from cooling ponds. There were three categories of measurements. (1) Ambient weather data including temperature, humidity, wind speed and wind direction. These measurements ...

  14. Film cooling for a closed loop cooled airfoil

    DOEpatents

    Burdgick, Steven Sebastian; Yu, Yufeng Phillip; Itzel, Gary Michael

    2003-01-01

    Turbine stator vane segments have radially inner and outer walls with vanes extending therebetween. The inner and outer walls are compartmentalized and have impingement plates. Steam flowing into the outer wall plenum passes through the impingement plate for impingement cooling of the outer wall upper surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. At least one film cooling hole is defined through a wall of at least one of the cavities for flow communication between an interior of the cavity and an exterior of the vane. The film cooling hole(s) are defined adjacent a potential low LCF life region, so that cooling medium that bleeds out through the film cooling hole(s) reduces a thermal gradient in a vicinity thereof, thereby the increase the LCF life of that region.

  15. Double field flip cooling channel for the neutrino factory

    SciTech Connect

    Valeri Balbekov et al.

    2001-07-03

    A 220 m long ionization cooling system consisting of three solenoids with two field-flip sections, is proposed as a cooling channel for the neutrino factory. The reduction of transverse emittance is achieved using 87 liquid hydrogen absorbers (30-40 cm long), and 87 (2 m long) 200 MHz linacs. The first flip is performed at relatively small magnetic field, B = 3 T, to keep the longitudinal motion under control. The field is then increased adiabatically up to 7 T and a second field flip performed. The cooler was studied and simulated in detail. Preceded by a 16 GeV proton driver, a carbon target, a mini-cooler and a buncher, the system provides about 0.082 muons per incident proton.

  16. Quench Protection for the MICE Cooling Channel Coupling Magnet

    SciTech Connect

    Guo, Xing Long; Xu, Feng Yu; Wang, Li; Green, Michael A.; Pan, Heng; Wu, Hong; Liu, X.K.; Jia, Lin Xiang; Amm, Kathleen

    2008-08-02

    This paper describes the passive quench protection system selected for the muon ionization cooling experiment (MICE) cooling channel coupling magnet. The MICE coupling magnet will employ two methods of quench protection simultaneously. The most important method of quench protection in the coupling magnet is the subdivision of the coil. Cold diodes and resistors are put across the subdivisions to reduce both the voltage to ground and the hot-spot temperature. The second method of quench protection is quench-back from the mandrel, which speeds up the spread of the normal region within the coils. Combining quench back with coil subdivision will reduce the hot spot temperature further. This paper explores the effect on the quench process of the number of coil sub-divisions, the quench propagation velocity within the magnet, and the shunt resistance.

  17. Theoretical studies of chromospheres and winds in cool stars

    NASA Technical Reports Server (NTRS)

    Dupree, A.

    1983-01-01

    The formation of spectral lines in expanding spherical atmospheres was determined in a physically realistic way, taking into account multilevel atomic processes, partial frequency redistribution, and other non-LTE transfer effects that affect the formation of optically thick lines. The formation of MgII and Ca II circumstellar absorption lines in late type giants and supergiants is investigated. The radiative cooling rate as a function of density and temperature was calculated from the results of plane parallel chromospheric models and these results were used to approximate the radiative cooling in an extended wind. The run of temperature was calculated along with the density and velocity profiles. The most important prediction of these models is that a warm zone in the wind must exist as a result of the wave heating. Within this zone, the Ca II and Mg II atoms can be ionized to Ca III and Mg III, so that the gas is transparent in the resonance transitions.

  18. Estimation of patient setup uncertainty using BrainLAB Exatrac X-Ray 6D system in image-guided radiotherapy.

    PubMed

    Infusino, Erminia; Trodella, Lucio; Ramella, Sara; D'Angelillo, Rolando M; Greco, Carlo; Iurato, Aurelia; Trodella, Luca E; Nacca, Alessandro; Cornacchione, Patrizia; Mameli, Alessandra

    2015-01-01

    The purpose of this study was to evaluate setup uncertainties for brain sites with ExacTrac X-Ray 6D system and to provide optimal margin guidelines. Fifteen patients with brain tumor were included in this study. Two X-ray images with ExacTrac X-Ray 6D system were used to verify patient position and tumor target localization before each treatment. The 6D fusion software first generates various sets of DRRs with position variations in both three translational and three rotational directions (six degrees of freedom) for the CT images. Setup variations (translation and rotation) after correction were recorded and corrected before treatment. The 3D deviations are expressed as mean ± standard deviation. The random error (Σ(σi)), systematic error (μi), and group systematic error (M(μi)) for the different X-ray were calculated using the definitions of van Herk.(1) Mean setup errors were calculated from X-ray images acquired after all fractions. There is moderate patient-to-patient variation in the vertical direction and small variations in systematic errors and magnitudes of random errors are smaller. The global systematic errors were measured to be less than 2.0 mm in each direction. Random component of all patients are smaller ranging from 0.1-0.3 mm small. The safety margin (SM) to the lateral, is 0.5 mm and 2.6 mm for van Herk(1) and Stroom et al.,(2) respectively, craniocaudal axis is 1.5 mm and 3.4 mm, respectively, and with respect to the antero-posterior axis, 2.3 mm and 3.9 mm. Daily X-ray imaging is essential to compare and assess the accuracy of treatment delivery to different anatomical locations. PMID:26103179

  19. Reference range for uterine artery Doppler pulsatility index using transvaginal ultrasound at 20–24w6d of gestation in a low-risk Brazilian population

    PubMed Central

    Peixoto, Alberto Borges; Da Cunha Caldas, Taciana Mara Rodrigues; Tonni, Gabriele; De Almeida Morelli, Priscilla; Santos, Larissa D’amico; Martins, Wellington P.; Júnior, Edward Araujo

    2016-01-01

    Objective To establish reference range for uterine artery (UtA) Doppler pulsatility index (PI) using transvaginal ultrasound at 20–24w6d of gestation in a Brazilian population. Material and Methods A retrospective cross-sectional study in 847 low-risk pregnant women undergoing routine second trimester ultrasound examination was conducted from February 2012 through March 2015. The mean UtA PI was calculated using color Doppler ultrasound with UtA gated at the level of the internal os. Mean±standard deviation and ranges for UtA Doppler PI in relation to gestational age (GA) are reported. Polynomial regression was used to obtain the best fit using mean UtA Doppler PI and GA (weeks) with adjustments performed using determination coefficient (R2). The 5th, 50th, and 95th percentiles for the mean UtA Doppler PI in relation to GA were determined. Results The mean UtA Doppler PI ranged from 1.14 at 20 weeks to 0.95 at 24 weeks of gestation. The best-fit curve of mean UtA Doppler PI as a function of GA was a first-degree polynomial regression: mean UtA Doppler PI=1.900−0.038×GA (R2=0.01). Conclusion In summary, when the mean UtA PI Doppler values were measured by transvaginal ultrasound at 20–24w6d of gestation, decrease in UtA Doppler PI values with advancing GA was observed. Reference range for the mean UtA Doppler PI at 20–24w6d of gestation using the transvaginal ultrasound in a low-risk Brazilian population was established. We believe that this reference range may be of clinical value in daily obstetric practice. PMID:27026774

  20. Metal--Insulator Transition in Bi{sub 2}Sr{sub 2}Cu{sub 1}O{sub 6+d}(Bi-2201) Thin Films

    SciTech Connect

    Pop, Aurel V.

    2009-05-22

    We have studied the influence of disorder induced by oxygen on the normal state resistivity of under doped Bi{sub 2}Sr{sub 2}Cu{sub 1}O{sub 6+d}(Bi-2201) thin films, deposited in situ onto heated SrTiO{sub 3}(100) substrates by using DC magnetron sputtering for an off-stoichiometric target. The compositions and structural characterization for the deposited films were carried by (EDX), (XPS) and X-ray diffraction measurements. The effect of partial oxygen pressure in the sputtering gas on the metal-insulator transition are presented.

  1. Intense laser ionization of transiently aligned CO

    SciTech Connect

    Pinkham, D.; Jones, R.R.

    2005-08-15

    We have measured the ionization rate for CO molecules exposed to intense 30 fsec 780 nm laser pulses as a function of the angle between the molecular and laser polarization axes. Nonionizing, 70 fsec laser pulses are used to coherently prepare the molecules, preferentially aligning them for the strong-field ionization experiments. We find a 2:1 ionization-rate ratio for molecules aligned parallel or perpendicular to the ionizing field.

  2. Five-photon double ionization of helium

    NASA Astrophysics Data System (ADS)

    Li, Y.; Pindzola, M. S.; Colgan, J.

    2016-03-01

    A time-dependent close-coupling method is used to calculate the five-photon double ionization of He. It is found that the generalized cross section used in the past for two-photon double ionization of He cannot be extended to five-photon double ionization of He. Therefore only five-photon double ionization probabilities that depend on specific radiation field pulses can be calculated.

  3. Newton's Law of Cooling Revisited

    ERIC Educational Resources Information Center

    Vollmer, M.

    2009-01-01

    The cooling of objects is often described by a law, attributed to Newton, which states that the temperature difference of a cooling body with respect to the surroundings decreases exponentially with time. Such behaviour has been observed for many laboratory experiments, which led to a wide acceptance of this approach. However, the heat transfer…

  4. Temperature initiated passive cooling system

    DOEpatents

    Forsberg, C.W.

    1994-11-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature. 1 fig.

  5. Temperature initiated passive cooling system

    DOEpatents

    Forsberg, Charles W.

    1994-01-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature.

  6. Automotive Cooling and Lubricating Systems.

    ERIC Educational Resources Information Center

    Marine Corps Inst., Washington, DC.

    This correspondence course, originally developed for the Marine Corps, is designed to provide new mechanics with a source of study materials to assist them in becoming more proficient in their jobs. The course contains four study units covering automotive cooling system maintenance, cooling system repair, lubricating systems, and lubrication…

  7. Stochastic cooling: recent theoretical directions

    SciTech Connect

    Bisognano, J.

    1983-03-01

    A kinetic-equation derivation of the stochastic-cooling Fokker-Planck equation of correlation is introduced to describe both the Schottky spectrum and signal suppression. Generalizations to nonlinear gain and coupling between degrees of freedom are presented. Analysis of bunch beam cooling is included.

  8. Electron-Impact Ionization and Dissociative Ionization of Biomolecules

    NASA Technical Reports Server (NTRS)

    Huo, Winifred M.; Chaban, Galina M.; Dateo, Christopher E.

    2006-01-01

    It is well recognized that secondary electrons play an important role in radiation damage to humans. Particularly important is the damage of DNA by electrons, potentially leading to mutagenesis. Molecular-level study of electron interaction with DNA provides information on the damage pathways and dominant mechanisms. Our study of electron-impact ionization of DNA fragments uses the improved binary-encounter dipole model and covers DNA bases, sugar phosphate backbone, and nucleotides. An additivity principle is observed. For example, the sum of the ionization cross sections of the separate deoxyribose and phosphate fragments is in close agreement with the C3(sup prime)- and C5 (sup prime)-deoxyribose-phospate cross sections, differing by less than 5%. Investigation of tandem double lesion initiated by electron-impact dissociative ionization of guanine, followed by proton reaction with the cytosine in the Watson-Crick pair, is currently being studied to see if tandem double lesion can be initiated by electron impact. Up to now only OH-induced tandem double lesion has been studied.

  9. Closed loop steam cooled airfoil

    SciTech Connect

    Widrig, Scott M.; Rudolph, Ronald J.; Wagner, Gregg P.

    2006-04-18

    An airfoil, a method of manufacturing an airfoil, and a system for cooling an airfoil is provided. The cooling system can be used with an airfoil located in the first stages of a combustion turbine within a combined cycle power generation plant and involves flowing closed loop steam through a pin array set within an airfoil. The airfoil can comprise a cavity having a cooling chamber bounded by an interior wall and an exterior wall so that steam can enter the cavity, pass through the pin array, and then return to the cavity to thereby cool the airfoil. The method of manufacturing an airfoil can include a type of lost wax investment casting process in which a pin array is cast into an airfoil to form a cooling chamber.

  10. Experiences in solar cooling systems

    NASA Astrophysics Data System (ADS)

    Ward, D. S.

    The results of performance evaluations for nine solar cooling systems are presented, and reasons fow low or high net energy balances are discussed. Six of the nine systems are noted to have performed unfavorably compared to standard cooling systems due to thermal storage losses, excessive system electrical demands, inappropriate control strategies, poor system-to-load matching, and poor chiller performance. A reduction in heat losses in one residential unit increased the total system efficiency by 2.5%, while eliminating heat losses to the building interior increased the efficiency by 3.3%. The best system incorporated a lithium bromide absorption chiller and a Rankine cycle compression unit for a commercial application. Improvements in the cooling tower and fan configurations to increase the solar cooling system efficiency are indicated. Best performances are expected to occur in climates inducing high annual cooling loads.

  11. Evaporative cooling in microfluidic channels

    NASA Astrophysics Data System (ADS)

    Maltezos, George; Rajagopal, Aditya; Scherer, Axel

    2006-08-01

    Evaporative cooling is an effective and energy efficient way to rapidly remove heat from a system. Specifically, evaporative cooling in microfluidic channels can provide a cost-effective solution for the cooling of electronic devices and chemical reactors. Here we present microfluidic devices fabricated by using soft-lithography techniques to form simple fluidic junctions between channels carrying refrigerant and channels carrying N2 gas. The effects of channel geometry and delivery pressure on the performance of refrigeration through vaporization of acetone, isopropyl alcohol, and ethyl ether were characterized. By varying gas inlet pressures, refrigerants, and angles of the microfluidic junctions, optimal cooling conditions were found. Refrigeration rates in excess of 40°C/s were measured, and long lasting subzero cooling in the junction could be observed.

  12. New fine structure cooling rate

    NASA Technical Reports Server (NTRS)

    Hoegy, W. R.

    1976-01-01

    One of the dominant electron cooling processes in the ionosphere is caused by electron impact induced fine structure transitions among the ground state levels of atomic oxygen. This fine structure cooling rate is based on theoretical cross sections. Recent advances in the numerical cross section determinations to include polarization effects and more accurate representations of the atomic target result in new lower values. These cross sections are employed in this paper to derive a new fine structure cooling rate which is between 40% and 60% of the currently used rate. A new generalized formula is presented for the cooling rate (from which the fine structure cooling rate is derived), valid for arbitrary mass and temperature difference of the colliding particles and arbitrary inelastic energy difference.

  13. Film cooling air pocket in a closed loop cooled airfoil

    DOEpatents

    Yu, Yufeng Phillip; Itzel, Gary Michael; Osgood, Sarah Jane; Bagepalli, Radhakrishna; Webbon, Waylon Willard; Burdgick, Steven Sebastian

    2002-01-01

    Turbine stator vane segments have radially inner and outer walls with vanes extending between them. The inner and outer walls are compartmentalized and have impingement plates. Steam flowing into the outer wall plenum passes through the impingement plate for impingement cooling of the outer wall upper surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. To provide for air film cooing of select portions of the airfoil outer surface, at least one air pocket is defined on a wall of at least one of the cavities. Each air pocket is substantially closed with respect to the cooling medium in the cavity and cooling air pumped to the air pocket flows through outlet apertures in the wall of the airfoil to cool the same.

  14. GENETIC MAPPING OF VOCALIZATION TO A SERIES OF INCREASING ACUTE FOOTSHOCKS USING B6.A CONSOMIC AND B6.D2 CONGENIC MOUSE STRAINS

    SciTech Connect

    Matthews, Douglas B; Chesler, Elissa J; Cook, Melloni N.; Cockroft, Judy; Philip, Vivek M; Goldowitz, Daniel

    2008-01-01

    Footshock response is used to study biological functions in mammals. However, the genetics underlying variability in footshock sensitivity are not well understood. In the current studies, a panel of B6.A consomic mouse strains, two B6.D2 congenic mouse strains and the progenitor strains were screened for footshock sensitivity as measured by audible vocalization. It was found that A/J (A) mice and C57BL/6J (B6) mice with an A Chromosome 1 (Chr 1) were less sensitive to footshock compared to B6 animals. Furthermore, the offspring of Chr 1 consomic mice crossed with B6 mice had vocalization levels that were intermediate to A/J and B6 animals. A F2 mapping panel revealed two significant QTLs for footshock vocalization centered around D1Mit490 and D1Mit206 on Chr 1. The role of these Chr 1 loci in footshock sensitivity was confirmed in B6.D2 congenic mice. These data identify genetic regions involved in footshock sensitivity and establish additional mouse resources for use in investigating complex behaviors.

  15. HR96 and BR-C modulate phenobarbital induced transcription of cytochrome P450 CYP6D1 in Drosophila S2 cells

    PubMed Central

    Lin, G. G.-H.; Kozaki, T.; Scott, J. G.

    2010-01-01

    Phenobarbital (PB) is a prototypical inducer for studies of xenobiotic responses in animals. In mammals, nuclear receptors CAR and PXR have been identified as key transcription factors regulating PB induced transcription of xenobiotic responsive genes. In insects, much less is known about transcription factors involved in regulating PB induced transcription, although CAR and PXR have a single ortholog, HR96 (hormone receptor-like in 96), in Drosophila melanogaster. Using dual luciferase reporter assays in Drosophila S2 cells, constructs containing variable lengths of the promoter of the PB inducible cytochrome P450 CYP6D1 were evaluated in the presence and absence of PB. The promoter region between −330 and −280 (relative to the position of transcription start site, +1) was found to be critical for PB induction. Putative binding sites for Drosophila BR-C (broad-complex) and DFD (deformed) were identified within this promoter region using TFsearch. RNAi treatment of S2 cells in conjunction with CYP6D1 promoter assays showed that suppression of Drosophila HR96 and BR-C transcription in S2 cells resulted in a significant decrease and increase, respectively, of PB induction. Effects of HR96 and BR-C in mediating PB induction were PB specific and dependent. This represents new functional evidence that Drosophila HR96 and BR-C can act as an activator and repressor, respectively, regulating PB induced transcription in insects. PMID:21029232

  16. Importance of combining convection with film cooling.

    NASA Technical Reports Server (NTRS)

    Colladay, R. S.

    1972-01-01

    The interaction of film and convection cooling and its effect on wall cooling efficiency is investigated analytically for two cooling schemes for advanced gas turbine applications. The two schemes are full coverage- and counterflow-film cooling. In full coverage film cooling, the cooling air issues from a large number of small discrete holes in the surface. Counterflow film cooling is a film-convection scheme with film injection from a slot geometry. The results indicate that it is beneficial to utilize as much of the cooling air heat sink as possible for convection cooling prior to ejecting it as a film.

  17. Importance of combining convection with film cooling

    NASA Technical Reports Server (NTRS)

    Colladay, R. S.

    1971-01-01

    The interaction of film and convection cooling and its effect on wall cooling efficiency is investigated analytically for two cooling schemes for advanced gas turbine applications. The two schemes are full coverage- and counterflow-film cooling. In full coverage film cooling, the cooling air issues from a large number of small discrete holes in the surface. Counterflow film cooling is a film-convection scheme with film injection from a slot geometry. The results indicate that it is beneficial to utilize as much of the cooling air heat sink as possible for convection cooling prior to ejecting it as a film.

  18. Metallic Glass Cooling

    NASA Technical Reports Server (NTRS)

    2003-01-01

    A sample of advanced metallic glass alloy cools down during an experiment with the TEMPUS furnace on STS-94, July 7, 1997, MET:5/23:35 (approximate). The sequence shows the sample glowing, then fading to black as scientists began the process of preserving the liquid state, but lowering the temperature below the normal solidification temperature of the alloy. This process is known as undercooling. (10 second clip covering approximately 50 seconds.) TEMPUS (stands for Tiegelfreies Elektromagnetisches Prozessiere unter Schwerelosigkeit (containerless electromagnetic processing under weightlessness). It was developed by the German Space Agency (DARA) for flight aboard Spacelab. The DARA project scientist was Igon Egry. The experiment was part of the space research investigations conducted during the Microgravity Science Laboratory-1R mission (STS-94, July 1-17 1997). DARA and NASA are exploring the possibility of flying an advanced version of TEMPUS on the International Space Station. (354KB JPEG, 2700 x 2038 pixels; downlinked video, higher quality not available) The MPG from which this composite was made is available at http://mix.msfc.nasa.gov/ABSTRACTS/MSFC-0300189.html.

  19. Acoustic cooling engine

    DOEpatents

    Hofler, Thomas J.; Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1988-01-01

    An acoustic cooling engine with improved thermal performance and reduced internal losses comprises a compressible fluid contained in a resonant pressure vessel. The fluid has a substantial thermal expansion coefficient and is capable of supporting an acoustic standing wave. A thermodynamic element has first and second ends and is located in the resonant pressure vessel in thermal communication with the fluid. The thermal response of the thermodynamic element to the acoustic standing wave pumps heat from the second end to the first end. The thermodynamic element permits substantial flow of the fluid through the thermodynamic element. An acoustic driver cyclically drives the fluid with an acoustic standing wave. The driver is at a location of maximum acoustic impedance in the resonant pressure vessel and proximate the first end of the thermodynamic element. A hot heat exchanger is adjacent to and in thermal communication with the first end of the thermodynamic element. The hot heat exchanger conducts heat from the first end to portions of the resonant pressure vessel proximate the hot heat exchanger. The hot heat exchanger permits substantial flow of the fluid through the hot heat exchanger. The resonant pressure vessel can include a housing less than one quarter wavelength in length coupled to a reservoir. The housing can include a reduced diameter portion communicating with the reservoir. The frequency of the acoustic driver can be continuously controlled so as to maintain resonance.

  20. Offset cooling coil fin

    SciTech Connect

    Griffin, C.K.; McCabe, M.P.

    1993-06-29

    An improved plate fin heat exchanger of the type having a plurality of longitudinally stacked plate fin members with each having a plurality of transversely spaced rows of openings formed therein, and tubes being disposed through successive aligned holes for conducting the flow of coolant therethrough for cooling air as it passes transversely between the plate fin members from a leading edge to a trailing edge thereof, wherein the improvement is described comprises: the plate fin leading edges being spaced from the nearest row of openings by one distance; the plate fin trailing edges being spaced from the nearest row of openings by another distance substantially greater than the one distance, such that when the trailing edges are oriented in a vertical disposition there is sufficient plate fin surface area near the trailing edge such that condensate residing thereon will tend to run vertically down the plate fin trailing edges rather than being blown off by the flow of air; and condensate collection means disposed below the plate fin trailing edges for receiving condensate flow from the lower ends thereof.

  1. 46 CFR 153.432 - Cooling systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a...

  2. 46 CFR 153.432 - Cooling systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cooling systems. 153.432 Section 153.432 Shipping COAST... Control Systems § 153.432 Cooling systems. (a) Each cargo cooling system must have an equivalent standby... cooling system. (b) Each tankship that has a cargo tank with a required cooling system must have a...

  3. Performance of Air-cooled Engine Cylinders Using Blower Cooling

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W; Ellerbrock, Herman H , Jr

    1936-01-01

    An investigation was made to obtain information on the minimum quantity of air and power required to cool conventional air cooled cylinders at various operating conditions when using a blower. The results of these tests show that the minimum power required for satisfactory cooling with an overall blower efficiency of 100 percent varied from 2 to 6 percent of the engine power depending on the operating conditions. The shape of the jacket had a large effect on the cylinder temperatures. Increasing the air speed over the front of the cylinder by keeping the greater part of the circumference of the cylinder covered by the jacket reduced the temperatures over the entire cylinder.

  4. Microwave remote sensing of ionized air.

    SciTech Connect

    Liao, S.; Gopalsami, N.; Heifetz, A.; Elmer, T.; Fiflis, P.; Koehl, E. R.; Chien, H. T.; Raptis, A. C.

    2011-07-01

    We present observations of microwave scattering from ambient room air ionized with a negative ion generator. The frequency dependence of the radar cross section of ionized air was measured from 26.5 to 40 GHz (Ka-band) in a bistatic mode with an Agilent PNA-X series (model N5245A) vector network analyzer. A detailed calibration scheme is provided to minimize the effect of the stray background field and system frequency response on the target reflection. The feasibility of detecting the microwave reflection from ionized air portends many potential applications such as remote sensing of atmospheric ionization and remote detection of radioactive ionization of air.

  5. Ultraviolet femtosecond laser ionization mass spectrometry.

    PubMed

    Imasaka, Totaro

    2008-01-01

    For this study, multiphoton ionization/mass spectrometry using an ultraviolet (UV) femtosecond laser was employed for the trace analysis of organic compounds. Some of the molecules, such as dioxins, contain several chlorine atoms and have short excited-state lifetimes due to a "heavy atom" effect. A UV femtosecond laser is, then, useful for efficient resonance excitation and subsequent ionization. A technique of multiphoton ionization using an extremely short laser pulse (e.g., <10 fs), referred to as "impulsive ionization," may have a potential for use in fragmentation-free ionization, thus providing information on molecular weight in mass spectrometry. PMID:18302290

  6. Low-density ionization behavior

    SciTech Connect

    Baker, G.A. Jr.

    1995-04-01

    As part of a continuing study of the physics of matter under extreme conditions, I give some results on matter at extremely low density. In particular I compare a quantum mechanical calculation of the pressure for atomic hydrogen with the corresponding pressure given by Thomas-Fermi theory. (This calculation differs from the ``confined atom`` approximation in a physically significant way.) Since Thomas-Fermi theory in some sense, represents the case of infinite nuclear charge, these cases should represent extremes. Comparison is also made with Saha theory, which considers ionization from a chemical point of view, but is weak on excited-state effects. In this theory, the pressure undergoes rapid variation as electron ionization levels are passed. This effect is in contrast to the smooth behavior of the Thomas-Fermi fixed temperature, complete ionization occurs in the low density limit, I study the case where the temperature goes appropriately to zero with the density. Although considerable modification is required, Saha theory is closer to the actual results for this case than is Thomas-Fermi theory.

  7. Theory of dissociative tunneling ionization

    NASA Astrophysics Data System (ADS)

    Svensmark, Jens; Tolstikhin, Oleg I.; Madsen, Lars Bojer

    2016-05-01

    We present a theoretical study of the dissociative tunneling ionization process. Analytic expressions for the nuclear kinetic energy distribution of the ionization rates are derived. A particularly simple expression for the spectrum is found by using the Born-Oppenheimer (BO) approximation in conjunction with the reflection principle. These spectra are compared to exact non-BO ab initio spectra obtained through model calculations with a quantum mechanical treatment of both the electronic and nuclear degrees of freedom. In the regime where the BO approximation is applicable, imaging of the BO nuclear wave function is demonstrated to be possible through reverse use of the reflection principle, when accounting appropriately for the electronic ionization rate. A qualitative difference between the exact and BO wave functions in the asymptotic region of large electronic distances is shown. Additionally, the behavior of the wave function across the turning line is seen to be reminiscent of light refraction. For weak fields, where the BO approximation does not apply, the weak-field asymptotic theory describes the spectrum accurately.

  8. Ionization coefficients in gas mixtures

    NASA Astrophysics Data System (ADS)

    Marić, D.; Šašić, O.; Jovanović, J.; Radmilović-Rađenović, M.; Petrović, Z. Lj.

    2007-03-01

    We have tested the application of the common E/N ( E—electric field, N—gas number density) or Wieland approximation [Van Brunt, R.J., 1987. Common parametrizations of electron transport, collision cross section, and dielectric strength data for binary gas mixtures. J. Appl. Phys. 61 (5), 1773-1787.] and the common mean energy (CME) combination of the data for pure gases to obtain ionization coefficients for mixtures. Test calculations were made for Ar-CH4, Ar-N2, He-Xe and CH4-N2 mixtures. Standard combination procedure gives poor results in general, due to the fact that the electron energy distribution is considerably different in mixtures and in individual gases at the same values of E/N. The CME method may be used for mixtures of gases with ionization coefficients that do not differ by more than two orders of magnitude which is better than any other technique that was proposed [Marić, D., Radmilović-Rađenović, M., Petrović, Z.Lj., 2005. On parametrization and mixture laws for electron ionization coefficients. Eur. Phys. J. D 35, 313-321.].

  9. Nanotip Ambient Ionization Mass Spectrometry.

    PubMed

    Zhou, Zhenpeng; Lee, Jae Kyoo; Kim, Samuel C; Zare, Richard N

    2016-05-17

    A method called nanotip ambient ionization mass spectrometry (NAIMS) is described, which applies high voltage between a tungsten nanotip and a metal plate to generate a plasma in which ionized analytes on the surface of the metal plate are directed to the inlet and analyzed by a mass spectrometer. The dependence of signal intensity is investigated as a function of the tip-to-plate distance, the tip size, the voltage applied at the tip, and the current. These parameters are separately optimized to achieve sensitivity or high spatial resolution. A partially observable Markov decision process is used to achieve a stabilized plasma as well as high ionization efficiency. As a proof of concept, the NAIMS technique has been applied to phenanthrene and caffeine samples for which the limits of detection were determined to be 0.14 fmol for phenanthrene and 4 amol for caffeine and to a printed caffeine pattern for which a spatial resolution of 8 ± 2 μm, and the best resolution of 5 μm, was demonstrated. The limitations of NAIMS are also discussed. PMID:27087600

  10. Polarization phenomena in multiphoton ionization of atoms

    NASA Technical Reports Server (NTRS)

    Jacobs, V. L.

    1973-01-01

    The theory of multiphoton ionization for an atomic system of arbitrary complexity is developed using a density matrix formalism. An expression is obtained which determines the differential N-photon ionization cross section as a function of the polarization states of the target atom and the incident radiation. The parameters which characterize the photoelectron angular distribution are related to the general reduced matrix elements for the N-photon transition. Two-photon ionization of unpolarized atoms is treated as an illustration of the use of the theory. The dependence of the multiphoton ionization cross section on the polarization state of the incident radiation, which has been observed in two- and three-photon ionization of Cs, is accounted for by the theory. Finally, the photoelectron spin polarization produced by the multiphoton ionization of unpolarized atoms, like the analogous polarization resulting from single-photon ionization, is found to depend on the circular polarization of the incident radiation.

  11. Relativistic ionization fronts in gas jets

    NASA Astrophysics Data System (ADS)

    Lemos, Nuno; Dias, J. M.; Gallacher, J. G.; Issac, R. C.; Fonseca, R. A.; Lopes, N. C.; Silva, L. O.; Mendonça, J. T.; Jaroszynski, D. A.

    2006-10-01

    A high-power ultra-short laser pulse propagating through a gas jet, ionizes the gas by tunnelling ionization, creating a relativistic plasma-gas interface. The relativistic ionization front that is created can be used to frequency up-shift electromagnetic radiation either in co-propagation or in counter-propagation configurations. In the counter-propagation configuration, ionization fronts can act as relativistic mirrors for terahertz radiation, leading to relativistic double Doppler frequency up-shift to the visible range. In this work, we identified and explored, the parameters that optimize the key features of relativistic ionization fronts for terahertz radiation reflection. The relativistic ionization front generated by a high power laser (TOPS) propagating in a supersonic gas jet generated by a Laval nozzle has been fully characterized. We have also performed detailed two-dimensional relativistic particle-in-cell simulations with Osiris 2.0 to analyze the generation and propagation of the ionization fronts.

  12. Non-intrusive cooling system

    DOEpatents

    Morrison, Edward F.; Bergman, John W.

    2001-05-22

    A readily replaceable heat exchange cooling jacket for applying fluid to a system conduit pipe. The cooling jacket comprises at least two members, separable into upper and lower portions. A chamber is formed between the conduit pipe and cooling jacket once the members are positioned about the pipe. The upper portion includes a fluid spray means positioned above the pipe and the bottom portion includes a fluid removal means. The heat exchange cooling jacket is adaptable with a drain tank, a heat exchanger, a pump and other standard equipment to provide a system for removing heat from a pipe. A method to remove heat from a pipe, includes the steps of enclosing a portion of the pipe with a jacket to form a chamber between an outside surface of the pipe and the cooling jacket; spraying cooling fluid at low pressure from an upper portion of the cooling jacket, allowing the fluid to flow downwardly by gravity along the surface of the pipe toward a bottom portion of the chamber; and removing the fluid at the bottom portion of the chamber.

  13. An Alternative to Laser Cooling

    NASA Astrophysics Data System (ADS)

    Raizen, Mark

    2015-03-01

    Laser cooling has been the standard approach for over thirty years for cooling the translational motion of atoms. While laser cooling is an extremely successful method, it has been limited to a small set of elements in the periodic table. The performance of laser cooling for those elements has saturated in terms of flux of ultra-cold atoms, density, and phase-space density. I report our progress towards the development of an alternative to laser cooling. Our approach relies on magnetic stopping of supersonic beams, an atomic coilgun. A recent advance is the experimental realization of an adiabatic coilgun which preserves phase-space density. Further cooling was demonstrated with a one-way wall, realizing the historic thought experiment of Maxwell's Demon. More recently, we showed how to apply this method to compress atomic phase space with almost no loss of atom number. Our approach is fundamentally different than laser cooling as it does not rely on the momentum of the photon, but rather the photon entropy. I will report on our experimental progress towards this goal, and describe future experiments that will be enabled by this work.

  14. Ionizing Radiation: how fungi cope, adapt, and exploit with the help of melanin

    PubMed Central

    Dadachova, Ekaterina; Casadevall, Arturo

    2008-01-01

    SUMMARY OF RECENT ADVANCES Life on Earth has always existed in the flux of ionizing radiation. However, fungi seem to interact with the ionizing radiation differently from other Earth’s inhabitants. Recent data show that melanized fungal species like those from Chernobyl’s reactor respond to ionizing radiation with enhanced growth. Fungi colonize space stations and adapt morphologically to extreme conditions. Radiation exposure causes upregulation of many key genes, and an inducible microhomology-mediated recombination pathway could be a potential mechanism of adaptive evolution in eukaryotes. The discovery of melanized organisms in high radiation environments, the space stations, Antarctic mountains, and in the reactor cooling water combined with phenomenon of ‘radiotropism’ raises the tantalizing possibility that melanins have functions analogous to other energy harvesting pigments such as chlorophylls. PMID:18848901

  15. Fragmentation of HCN in optically selected mass spectrometry: Nonthermal ion cooling in helium nanodroplets

    SciTech Connect

    Lewis, William K.; Bemish, Raymond J.; Miller, Roger E.

    2005-10-08

    A technique that combines infrared laser spectroscopy and helium nanodroplet mass spectrometry, which we refer to as optically selected mass spectrometry, is used to study the efficiency of ion cooling in helium. Electron-impact ionization is used to form He{sup +} ions within the droplets, which go on to transfer their charge to the HCN dopant molecules. Depending upon the droplet size, the newly formed ion either fragments or is cooled by the helium before fragmentation can occur. Comparisons with gas-phase fragmentation data suggest that the cooling provided by the helium is highly nonthermal. An 'explosive' model is proposed for the cooling process, given that the initially hot ion is embedded in such a cold solvent.

  16. Liquid Cooling in Data Centers

    SciTech Connect

    Cader, Tahir; Sorell,, Vali; Westra, Levi; Marquez, Andres

    2009-05-01

    Semiconductor manufacturers have aggressively attacked the problem of escalating microprocessor power consumption levels. Today, server manufacturers can purchase microprocessors that currently have power consumption levels capped at 100W maximum. However, total server power levels continue to increase, with the increase in power consumption coming from the supportin chipsets, memory, and other components. In turn, full rack heat loads are very aggressivley climbing as well, and this is making it increasingly difficult and cost-prohibitive for facility owners to cool these high power racks. As a result, facilities owners are turning to alternative, and more energy efficient, cooling solutions that deploy liquids in one form or another. The paper discusses the advent of the adoption of liquid-cooling in high performance computing centers. An overview of the following competing rack-based, liquid-cooling, technologies is provided: in-row, above rack, refrigerated/enclosed rack, rear door heat exchanger, and device-level (i.e., chip-level). Preparation for a liquid-cooled data center, retroft and greenfield (new), is discussed, with a focus on the key issues that are common to all liquid-cooling technologies that depend upon the delivery of water to the rack (or in some deployments, a Coolant Distribution Unit). The paper then discusses, in some detail, the actual implementation and deployment of a liquid device-level cooled (spray cooled) supercomputer at the Pacific Northwest National Laboratory. Initial results from a successful 30 day compliance test show excellent hardware stability, operating system (OS) and software stack stability, application stability and performance, and an availability level that exceeded expectations at 99.94%. The liquid-cooled supercomputer achieved a peak performance of 9.287 TeraFlops, which placed it at number 101 in the June 2007 Top500 fastest supercomputers worldwide. Long-term performance and energy efficiency testing is

  17. Cool Cities, Cool Planet (LBNL Science at the Theater)

    ScienceCinema

    Rosenfeld, Arthur; Pomerantz, Melvin; Levinson, Ronnen

    2011-04-28

    Science at the Theater: Berkeley Lab scientists discuss how cool roofs can cool your building, your city ... and our planet. Arthur Rosenfeld, Professor of Physics Emeritus at UC Berkeley, founded the Berkeley Lab Center for Building Science in 1974. He served on the California Energy Commission from 2000 to 2010 and is commonly referred to as California's godfather of energy efficiency. Melvin Pomerantz is a member of the Heat Island Group at Berkeley Lab. Trained as a physicist at UC Berkeley, he specializes in research on making cooler pavements and evaluating their effects. Ronnen Levinson is a staff scientist at Berkeley Lab and the acting leader of its Heat Island Group. He has developed cool roofing and paving materials and helped bring cool roof requirements into building energy efficiency standards.

  18. Cool Cities, Cool Planet (LBNL Science at the Theater)

    SciTech Connect

    Rosenfeld, Arthur; Pomerantz, Melvin; Levinson, Ronnen

    2010-10-11

    Science at the Theater: Berkeley Lab scientists discuss how cool roofs can cool your building, your city ... and our planet. Arthur Rosenfeld, Professor of Physics Emeritus at UC Berkeley, founded the Berkeley Lab Center for Building Science in 1974. He served on the California Energy Commission from 2000 to 2010 and is commonly referred to as California's godfather of energy efficiency. Melvin Pomerantz is a member of the Heat Island Group at Berkeley Lab. Trained as a physicist at UC Berkeley, he specializes in research on making cooler pavements and evaluating their effects. Ronnen Levinson is a staff scientist at Berkeley Lab and the acting leader of its Heat Island Group. He has developed cool roofing and paving materials and helped bring cool roof requirements into building energy efficiency standards.

  19. Neutral cloud theory of the Jovian nebula: Anomalous ionization effect of superthermal electrons

    NASA Technical Reports Server (NTRS)

    Barbosa, D. D.

    1994-01-01

    The standard model of the Jovian nebula postulates that its particle source is the extended cloud of neutral sulfur and oxygen atoms that escape from the satellite Io and become ionized through electron impact from the corotating plasma. Its energy source is the gyroenergy acquired by newly formed pickup ions as they are swept up to corotation velocity by the planetary magnetic field. Elastic collisions between plasma ions and electrons cool the ions and heat the electrons, while inelastic collisions cool the electrons and excite the ions to radiate intense line emission, which is the primary energy-loss mechanism for the plasma. This neutral cloud theory of the Io plasma torus, as it has come to be known, has been the subject of recent critcism which asserts that the theory cannot account for the observed charge state of the plasma which features O(+) and S(2+) as the dominant ions. It is shown in this work that the inclusion of a small population of super-thermal electrons is required to achieve the correct ion partitioning among various charge states. It is also argued that the anomalous ionization effect of the superthermal electrons is responsible for the overall spatial bifurcation of the nebula into a hot multiply charged plasma region outside of 5.7 Jovian radii and a cool singly ionized plasma inside this distance.

  20. PBF Cooling Tower. Hot deck of Cooling Tower with fan ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PBF Cooling Tower. Hot deck of Cooling Tower with fan motors in place. Fan's propeller blades (not in view) rotate within lower portion of vents. Inlet pipe is a left of view. Contractor's construction buildings in view to right. Photographer: Larry Page. Date: June 30, 1969. INEEL negative no. 69-3781 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

  1. Cooling by H3+ Emission

    NASA Astrophysics Data System (ADS)

    Miller, Steve; Stallard, Tom; Tennyson, Jonathan; Melin, Henrik

    2013-10-01

    Emission by the H3+ molecular ion may be important in determining the energy balance in astrophysical situations, such as in (exo)planetary atmospheres. Here we report the calculation of a new cooling function, based on refitted partition functions and a recalculation of the total energy emitted by the molecule. This new function gives significantly increased cooling at higher temperatures, typical of those found in the atmospheres of gas giants. It is shown that nonthermal effects also need to be considered. A link to a web-based code to calculate radiative cooling in H2/H3+ gas mixtures, including the effects of departures from equilibrium, is provided.

  2. Brightest Cluster Galaxies & Cooling Flows

    NASA Astrophysics Data System (ADS)

    Salomé, Philippe

    2013-03-01

    In the absence of any form of feedback heating, the gas in the central regions of massive relaxed cluster should cool and initiate a cooling flow. The presence/efficiency of an additional heating and the ultimate fate of the cooling gas is the subject of an extensive debate. In the last decade, molecular and atomic gas have been found in many Brightest Cluster Galaxies. I will review these observational results and discuss their implication for galaxy formation/evolution, in the perspective of ALMA.

  3. Hydrodynamic Models of Line-Driven Accretion Disk Winds III: Local Ionization Equilibrium

    NASA Technical Reports Server (NTRS)

    Pereyra, Nicolas Antonio; Kallman, Timothy R.; White, Nicholas E. (Technical Monitor)

    2002-01-01

    We present time-dependent numerical hydrodynamic models of line-driven accretion disk winds in cataclysmic variable systems and calculate wind mass-loss rates and terminal velocities. The models are 2.5-dimensional, include an energy balance condition with radiative heating and cooling processes, and includes local ionization equilibrium introducing time dependence and spatial dependence on the line radiation force parameters. The radiation field is assumed to originate in an optically thick accretion disk. Wind ion populations are calculated under the assumption that local ionization equilibrium is determined by photoionization and radiative recombination, similar to a photoionized nebula. We find a steady wind flowing from the accretion disk. Radiative heating tends to maintain the temperature in the higher density wind regions near the disk surface, rather than cooling adiabatically. For a disk luminosity L (sub disk) = solar luminosity, white dwarf mass M(sub wd) = 0.6 solar mass, and white dwarf radii R(sub wd) = 0.01 solar radius, we obtain a wind mass-loss rate of M(sub wind) = 4 x 10(exp -12) solar mass yr(exp -1) and a terminal velocity of approximately 3000 km per second. These results confirm the general velocity and density structures found in our earlier constant ionization equilibrium adiabatic CV wind models. Further we establish here 2.5D numerical models that can be extended to QSO/AGN winds where the local ionization equilibrium will play a crucial role in the overall dynamics.

  4. Multifluid magnetohydrodynamics of weakly ionized plasmas

    NASA Astrophysics Data System (ADS)

    Menzel, Raymond

    show that the total electric field in the asteroid may either be of comparable strength to the electric field predicted by Sonett et al. or vanish depending on the magnetic field geometry. We include the effects of dust grains in the gas and calculate the heating rates in the plasma flow due to ion-neutral scattering and viscous dissipation. We term this newly discovered heating mechanism "electrodynamic heating", use measurements of asteroid electrical conductivities to estimate the upper limits of the possible heating rates and amount of thermal energy that can be deposited in the solid body, and compare these to the heating produced by the decay of radioactive nuclei like Al26. For the second problem we modeled molecular line emission from time-dependent multifluid MHD shock waves in star-forming regions. By incorporating realistic radiative cooling by CO and H2 into the numerical method developed by Ciolek & Roberge (2013), we present the only current models of truly time-dependent multifluid MHD shock waves in weakly-ionized plasmas. Using the physical conditions determined by our models, we present predictions of molecular emission in the form of excitation diagrams, which can be compared to observations of protostellar outflows in order to trace the physical conditions of these environments. Current work focuses on creating models for varying initial conditions and shock ages, which are and will be the subject of several in progress studies of observed molecular outflows and will provide further insight into the physics and chemistry of these flows.

  5. Cooling arrangement for a tapered turbine blade

    SciTech Connect

    Liang, George

    2010-07-27

    A cooling arrangement (11) for a highly tapered gas turbine blade (10). The cooling arrangement (11) includes a pair of parallel triple-pass serpentine cooling circuits (80,82) formed in an inner radial portion (50) of the blade, and a respective pair of single radial channel cooling circuits (84,86) formed in an outer radial portion (52) of the blade (10), with each single radial channel receiving the cooling fluid discharged from a respective one of the triple-pass serpentine cooling circuit. The cooling arrangement advantageously provides a higher degree of cooling to the most highly stressed radially inner portion of the blade, while providing a lower degree of cooling to the less highly stressed radially outer portion of the blade. The cooling arrangement can be implemented with known casting techniques, thereby facilitating its use on highly tapered, highly twisted Row 4 industrial gas turbine blades that could not be cooled with prior art cooling arrangements.

  6. Analysis of the Setup Uncertainty and Margin of the Daily ExacTrac 6D Image Guide System for Patients with Brain Tumors

    PubMed Central

    Oh, Se An; Yea, Ji Woon; Kang, Min Kyu; Park, Jae Won; Kim, Sung Kyu

    2016-01-01

    This study evaluated the setup uncertainties for brain sites when using BrainLAB’s ExacTrac X-ray 6D system for daily pretreatment to determine the optimal planning target volume (PTV) margin. Between August 2012 and April 2015, 28 patients with brain tumors were treated by daily image-guided radiotherapy using the BrainLAB ExacTrac 6D image guidance system of the Novalis-Tx linear accelerator. DUONTM (Orfit Industries, Wijnegem, Belgium) masks were used to fix the head. The radiotherapy was fractionated into 27–33 treatments. In total, 844 image verifications were performed for 28 patients and used for the analysis. The setup corrections along with the systematic and random errors were analyzed for six degrees of freedom in the translational (lateral, longitudinal, and vertical) and rotational (pitch, roll, and yaw) dimensions. Optimal PTV margins were calculated based on van Herk et al.’s [margin recipe = 2.5∑ + 0.7σ - 3 mm] and Stroom et al.’s [margin recipe = 2∑ + 0.7σ] formulas. The systematic errors (∑) were 0.72, 1.57, and 0.97 mm in the lateral, longitudinal, and vertical translational dimensions, respectively, and 0.72°, 0.87°, and 0.83° in the pitch, roll, and yaw rotational dimensions, respectively. The random errors (σ) were 0.31, 0.46, and 0.54 mm in the lateral, longitudinal, and vertical rotational dimensions, respectively, and 0.28°, 0.24°, and 0.31° in the pitch, roll, and yaw rotational dimensions, respectively. According to van Herk et al.’s and Stroom et al.’s recipes, the recommended lateral PTV margins were 0.97 and 1.66 mm, respectively; the longitudinal margins were 1.26 and 3.47 mm, respectively; and the vertical margins were 0.21 and 2.31 mm, respectively. Therefore, daily setup verifications using the BrainLAB ExacTrac 6D image guide system are very useful for evaluating the setup uncertainties and determining the setup margin. PMID:27019082

  7. Analysis of the Setup Uncertainty and Margin of the Daily ExacTrac 6D Image Guide System for Patients with Brain Tumors.

    PubMed

    Oh, Se An; Yea, Ji Woon; Kang, Min Kyu; Park, Jae Won; Kim, Sung Kyu

    2016-01-01

    This study evaluated the setup uncertainties for brain sites when using BrainLAB's ExacTrac X-ray 6D system for daily pretreatment to determine the optimal planning target volume (PTV) margin. Between August 2012 and April 2015, 28 patients with brain tumors were treated by daily image-guided radiotherapy using the BrainLAB ExacTrac 6D image guidance system of the Novalis-Tx linear accelerator. DUONTM (Orfit Industries, Wijnegem, Belgium) masks were used to fix the head. The radiotherapy was fractionated into 27-33 treatments. In total, 844 image verifications were performed for 28 patients and used for the analysis. The setup corrections along with the systematic and random errors were analyzed for six degrees of freedom in the translational (lateral, longitudinal, and vertical) and rotational (pitch, roll, and yaw) dimensions. Optimal PTV margins were calculated based on van Herk et al.'s [margin recipe = 2.5∑ + 0.7σ - 3 mm] and Stroom et al.'s [margin recipe = 2∑ + 0.7σ] formulas. The systematic errors (∑) were 0.72, 1.57, and 0.97 mm in the lateral, longitudinal, and vertical translational dimensions, respectively, and 0.72°, 0.87°, and 0.83° in the pitch, roll, and yaw rotational dimensions, respectively. The random errors (σ) were 0.31, 0.46, and 0.54 mm in the lateral, longitudinal, and vertical rotational dimensions, respectively, and 0.28°, 0.24°, and 0.31° in the pitch, roll, and yaw rotational dimensions, respectively. According to van Herk et al.'s and Stroom et al.'s recipes, the recommended lateral PTV margins were 0.97 and 1.66 mm, respectively; the longitudinal margins were 1.26 and 3.47 mm, respectively; and the vertical margins were 0.21 and 2.31 mm, respectively. Therefore, daily setup verifications using the BrainLAB ExacTrac 6D image guide system are very useful for evaluating the setup uncertainties and determining the setup margin. PMID:27019082

  8. ON THE ORIGIN OF THE EXTENDED H{alpha} FILAMENTS IN COOLING FLOW CLUSTERS

    SciTech Connect

    McDonald, Michael; Veilleux, Sylvain; Mushotzky, Richard; Rupke, David S. N. E-mail: mcdonald@astro.umd.ed

    2010-10-01

    We present a high spatial resolution H{alpha} survey of 23 cooling flow clusters using the Maryland Magellan Tunable Filter, covering 1-2 orders of magnitude in cooling rate, dM/dt, temperature, and entropy. We find that 8/23 (35%) of our clusters have complex, filamentary morphologies at H{alpha}, while an additional 7/23 (30%) have marginally extended or nuclear H{alpha} emission, in general agreement with previous studies of line emission in cooling flow cluster brightest cluster galaxies. A weak correlation between the integrated near-UV luminosity and the H{alpha} luminosity is also found for our complete sample with a large amount of scatter about the expected relation for photoionization by young stars. We detect H{alpha} emission out to the X-ray cooling radius, but no further, in several clusters and find a strong correlation between the H{alpha} luminosity contained in filaments and the X-ray cooling flow rate of the cluster, suggesting that the warm ionized gas is linked to the cooling flow. Furthermore, we detect a strong enhancement in the cooling properties of the intracluster medium (ICM) coincident with the H{alpha} emission, compared to the surrounding ICM at the same radius. While the filaments in a few clusters may be entrained by buoyant radio bubbles, in general, the radially infalling cooling flow model provides a better explanation for the observed trends. The correlation of the H{alpha} and X-ray properties suggests that conduction may be important in keeping the filaments ionized. The thinness of the filaments suggests that magnetic fields are an important part of channeling the gas and shielding it from the surrounding hot ICM.

  9. Observational and Modeling Study of Pickup Ion Cooling Behavior in Solar Wind Compression and Rarefaction Regions

    NASA Astrophysics Data System (ADS)

    Chen, J.; Moebius, E.; Schwadron, N.; Klecker, B.; Bzowski, M.; Galvin, A. B.; Isenberg, P. A.; Sokol, J. M.; Gorby, M.; Bochsler, P. A.

    2013-12-01

    In many previous studies, the velocity distribution function of interstellar pickup ions (PUIs), which are produced by ionization of interstellar neutral atoms in the solar wind, were described as evolving through fast pitch angle scattering followed by adiabatic cooling during radial transport with in the reference frame of the solar wind [e.g., Vasyliunas & Siscoe, 1976 VS76 hereafter]. In the VS76 model, the slope of the velocity distributions is controlled by the combination of the ionization rate and the cooling process. Recently, Chen et al. [2013] have shown that the related adiabatic cooling index varies with solar activity between ~1 and 2, compared with 1.5 predicted by the VS76 model. Contributors to the observed variations include solar wind compression and rarefaction regions. Here, we performed a statistical study of the PUI cooling behavior in solar wind compression and rarefaction regions based on STEREO-A PLASTIC data sets using a set of events from the co-rotating interaction region (CIR) list (http://www-scc.igpp.ucla.edu/forms/stereo/stereo_level_3.html). We found that PUIs undergo stronger cooling in rarefaction regions and weaker cooling in compression regions. In order to analyze the PUI cooling behavior under these conditions, we modeled the PUI velocity distributions in CIRs using the Energetic Particle Radiation Environment Module (EPREM) [Schwadron et al., 2010]. For this analysis, we adopted a magneto-hydrodynamic CIR model proposed by [Giacalone et al., 2002]. The resulting PUI distributions exhibit a flatter slope in the compression region and are steeper in the rarefaction region compared with those in the undisturbed solar wind, in accordance with STEREO observations. These results indicate that gradients in the solar wind speed, as observed in CIRs, have substantial effects on the PUI cooling process.

  10. Muon cooling in a quadrupole magnet channel

    SciTech Connect

    Neuffer, David; Poklonskiy, A.; /Michigan State U.

    2007-10-01

    As discussed before,[1] a cooling channel using quadrupole magnets in a FODO transport channel can be used for initial cooling of muons. In the present note we discuss this possibility of a FODO focusing channel for cooling, and we present ICOOL simulations of muon cooling within a FODO channel. We explore a 1.5m cell-length cooling channel that could be used for the initial transverse cooling stage of a muon collider or neutrino factory.

  11. Femtosecond Laser Ionization of Organic Amines with Very Low Ionization Potential.

    NASA Astrophysics Data System (ADS)

    Yatsuhashi, Tomoyuki; Obayashi, Takashi; Tanaka, Michinori; Murakami, Masanao; Nakashima, Nobuaki

    2006-03-01

    The interaction between high intensity femtosecond laser and molecules is one of the most attractive areas in laser chemistry and ionization is the most fundamental subject. Theoretical consideration successfully reproduced the ionization behavior of rare gases. However, the understanding of ionization mechanisms of large molecules is difficult more than those of rare gases due to their complexity. Generally speaking, molecules are harder to ionize than rare gases even if they have the same ionization potential. The suppressed ionization phenomena are one of the important features of molecular ionization. Hankin et al. examined 23 organic molecules with ionization potentials between 8.25 and 11.52 eV. We have examined ionization and/ or fragmentation of many organic molecules, including aromatic compounds, halogenated compounds, methane derivatives etc. at various wavelengths below 10^16 Wcm-2. In order to investigate the nature of molecular ionization, it is interesting to examine a variety of molecule in a wide range of ionization potential. In this study, we examined several organic amines because we can explore the uninvestigated ionization potential range down to 5.95 eV. In addition to the significant suppression of the ionization rates, stepwise ionization behavior, which was not observed in rare gases, was observed.

  12. Sub-Cooled Pool Boiling Enhancement with Nanofluids

    NASA Astrophysics Data System (ADS)

    Rice, Elliott Charles

    Phase-change heat transfer is an important process used in many engineering thermal designs. Boiling is an important phase change phenomena as it is a common heat transfer process in many thermal systems. Phase change processes are critical to thermodynamic cycles as most closed loop systems have an evaporator, in which the phase change process occurs. There are many applications/processes in which engineers employ the advantages of boiling heat transfer, as they seek to improve heat transfer performance. Recent research efforts have experimentally shown that nanofluids can have significantly better heat transfer properties than those of the pure base fluids, such as water. The objective of this study is to improve the boiling curve of de-ionized water by adding aluminum oxide nanoparticles in 0.1%, 0.2%, 0.3% and 0.4% wt concentrations in a sub-cooled pool boiling apparatus. Enhancement to the boiling curve can be quantified in two ways: (i) the similar heat fluxes of de-ionized water at smaller excess temperature, indicating similar quantity of heat removal at lower temperatures and (ii) greater heat fluxes than de-ionized water at similar excess temperatures indicating better heat transfer at similar excess temperatures. In the same fashion, the secondary objective is to increase the convective heat transfer coefficient due to boiling by adding different concentrations of aluminum oxide nanoparticles.

  13. Electronic structure of neutral and singly ionized curium

    SciTech Connect

    Worden, E.F.; Conway, J.G.; Blaise, J.

    1985-02-01

    Extensive observations and analyses of the emission spectra of neutral and singly ionized curium, Cm I and Cm II, have resulted in the determination of 785 Cm I and 598 Cm II energy levels. These levels then combine to classify 9145 of the more than 14,250 lines of /sup 244/Cm observed between 240 and 2650 nm. Most of the levels have Lande g-values from Zeeman effect data and isotope shifts trom measurements of spectra from sources with various enrichments of /sup 244/Cm, /sup 245/Cm, /sup 246/Cm, and /sup 248/Cm. These data allowed many levels to be assigned to specific electronic configurations. The ground configurations of Cm I and Cm II are (Rn) 5f/sup 7/6d7s/sup 2/ and (Rn) 5f/sup 7/7s/sup 2/, respectively. The realtive energies of other electronic configurations of Cm are given and compared with analogous configurations in other actinides and in Gd its lanthanide analogue. 2 refs., 5 figs., 7 tabs.

  14. Hydrogen film/conductive cooling

    NASA Technical Reports Server (NTRS)

    Ewen, R. L.

    1972-01-01

    Small scale nozzle tests using heated nitrogen were run to obtain effectiveness and wall heat transfer data with hydrogen film cooling. Effectiveness data are compared with an entrainment model developed from planar, unaccelerated flow data. Results indicate significant effects due to flow turning and acceleration. With injection velocity effects accounted for explicitly, heat transfer correlation coefficients were found to be the same with and without film cooling when properties are evaluated at an appropriate reference temperature for the local gas composition defined by the coolant effectiveness. A design study for an O2/H2 application with 300 psia (207 N/sq cm) chamber pressure and 1500 lbs (6670 N) thrust indicates an adiabatic wall design requires 4 to 5 percent of the total flow as hydrogen film cooling. Internal regenerative cooling designs were found to offer no reduction in coolant requirements.

  15. Debuncher Cooling Limitations to Stacking

    SciTech Connect

    Halling, Mike

    1991-08-13

    During the January studies period we performed studies to determine the effect that debuncher cooling has on the stacking rate. Two different sets of measurements were made separated by about a week. Most measurements reported here are in PBAR log 16, page 243-247. These measurements were made by changing the accelerator timeline to give about 6 seconds between 29's, and then gating the cooling systems to simulate reduced cycle times. For the measurement of the momentum cooling effectiveness the gating switches could not be made to work, so the timeline was changed for each measurement. The cooling power of all three systems was about 800 watts for the tests reported here. We now regularly run at 1200 watts per system.

  16. Acoustical Convective Cooling Or Heating

    NASA Technical Reports Server (NTRS)

    Trinh, Eugene H.; Robey, Judith L.

    1988-01-01

    Small, efficient ultrasonic device circulates fluid. Vibrating at ultrasonic frequency, piezoelectric driver sets up vortexes transfering heat to or from object in space. Used on Earth to apply localized or concentrated cooling to individual electronic components or other small parts.

  17. Ozonation of cooling tower waters

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; French, K. R.; Howe, R. D. (Inventor)

    1979-01-01

    Continuous ozone injection into water circulating between a cooling tower and heat exchanger with heavy scale deposits inhibits formation of further deposits, promotes flaking of existing deposits, inhibits chemical corrosion and controls algae and bacteria.

  18. Sun Heats, Cools Columbus Tech.

    ERIC Educational Resources Information Center

    American School and University, 1980

    1980-01-01

    Solar energy heats and cools the newest building on the campus of Columbus Technical Institute in Ohio. A solar demonstration project grant from the Department of Energy covered about 77 percent of the solar cost. (Author/MLF)

  19. Combustion effects on film cooling

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.; Ewen, R. L.

    1977-01-01

    The effects of: (1) a reactive environment on film cooling effectiveness, and (2) film cooling on rocket engine performance were determined experimentally in a rocket thrust chamber assembly operating with hydrogen and oxygen propellants at 300 psi chamber pressure. Tests were conducted using hydrogen, helium, and nitrogen film coolants in an instrumented, thin walled, steel thrust chamber. The film cooling, performance loss, and heat transfer coefficient data were correlated with the ALRC entrainment film cooling model which relates film coolant effectiveness and mixture ratio at the wall to the amount of mainstream gases entrained with the film coolant in a mixing layer. In addition, a comprehensive thermal analysis computer program, HOCOOL, was prepared from previously existing ALRC computer programs and analytical techniques.

  20. Full-coverage film cooling

    NASA Technical Reports Server (NTRS)

    Meitner, P. L.

    1980-01-01

    Program calculates coolant flow and wall temperatures of full-coverage film-cooled vanes or blades. Thermal barrier coatings may be specified on outer surfaces of blade. Program is written in FORTRAN IV for batch execution on UNIVAC 1100.