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1

On the method of positron lifetime measurement  

NASA Technical Reports Server (NTRS)

A fast-slow coincidence system was constructed for the measurement of positron lifetimes in material. The time resolution of this system was 270 ps for the (60)Co gamma rays. Positron lifetime spectra for 14 kinds of alkali halides were measured with this system. Two lifetime components and their intensities were derived from analyses of the lifetime spectra.

Nishiyama, F.; Shizuma, K.; Nasai, H.; Nishi, M.

1983-01-01

2

Positron lifetime measurements in chiral nematic liquid crystals  

NASA Technical Reports Server (NTRS)

Positron lifetimes in the isotropic phases of chiral nematic liquid crystal formulations and their mixtures up to the racemic level were measured. The lifetime spectra for all liquid crystal systems were analyzed into three components. Although the individual spectra in the left- and right-handed components are identical, their racemic mixtures exhibit much larger orthopositronium lifetimes; these larger lifetimes indicate the presence of larger microvoids. This result is consistent with the reportedly higher thermodynamic stability and color play range in the racemic mixtures of chiral nematic liquid crystals.

Singh, Jag J.; Eftekhari, Abe; Parmar, Devendra S.

1991-01-01

3

Positron lifetime measurements by proton capture F. A. Selim,a  

E-print Network

Positron lifetime measurements by proton capture F. A. Selim,a D. P. Wells, and J. F. Harmon December 2004; published online 22 February 2005 A positron lifetime spectroscopy PLS technique coincident MeV rays, allowing positron lifetime to be measured. One quantum provides a start signal

Collins, Gary S.

4

Positron Lifetime Measurements in Semi-Interpenetrating Polymer Networks  

NASA Astrophysics Data System (ADS)

Physical interlocking is generally believed to be the dominant force that controls the morphology of a Semi-Interpenetrating Polymer Network (S-IPN). However, in our recent study (J. J. Singh, R. H. Pater, and A. Eftekhari: Nuclear Instruments and Methods - NIMB (To be published)) of S-IPN's prepared from thermosetting LaRC-RP46 and thermoplastic LaRC-IA polyimides, it was discovered that a strong electrostatic interaction between the constituent molecules enhances phase mixing. In order to further test this hypothesis, we replaced thermoplastic LaRC-IA by LaRC-SI. LaRC-SI has a rigid backbone which should prevent it from coming close to LaRCT-RP46 molecular chain, thereby minimizing electrostatic influences. Positron lifetime measurements were made in the new class of S-IPN samples. Experimental values of the free volume and the dielectric constant indicate that they are merely solid solutions of their constituents, without any measurable electrostatic effects. However, the density values of these materials suggest a slight repulsion (or enhanced separation) between the constituent chains.

Singh, Jag J.; Pater, Ruth H.; Sprinkle, Danny R.

1998-03-01

5

Positron lifetime measurements of hydrogen passivation of cation vacancies in yttrium aluminum oxide garnets  

NASA Astrophysics Data System (ADS)

A charge compensation mechanism is proposed for cation vacancy defects in complex oxides based on positron lifetime measurements, infrared spectroscopy, and composition analysis. Defects were characterized in samples of yttrium aluminum garnet grown in O2 or Ar. However, no positron trapping was detected in samples grown in H2. This is attributed to decoration of cation vacancies with hydrogen, thereby passivating charges of vacancies that otherwise function as positron traps. Infrared spectroscopy gave direct evidence of the presence of hydrogen. Passivation of cation vacancies with hydrogen is proposed as an important mechanism for charge compensation in the defect physics of oxides.

Selim, F. A.; Varney, C. R.; Tarun, M. C.; Rowe, M. C.; Collins, G. S.; McCluskey, M. D.

2013-11-01

6

Tomographic Positron Annihilation Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy serves as a perfect tool for studies of open-volume defects in solid materials such as vacancies, vacancy agglomerates, and dislocations. Moreover, structures in porous media can be investigated ranging from 0.3 nm to 30 nm employing the variation of the Positronium lifetime with the pore size. While lifetime measurements close to the material's surface can be performed at positron-beam installations bulk materials, fluids, bio-materials or composite structures cannot or only destructively accessed by positron beams. Targeting those problems, a new method of non-destructive positron annihilation lifetime spectroscopy has been developed which features even a 3-dimensional tomographic reconstruction of the spatial lifetime distribution. A beam of intense bremsstrahlung is provided by the superconducting electron linear accelerator ELBE (Electron Linear Accelerator with high Brilliance and low Emittance) at Helmholtz-Zentrum Dresden-Rossendorf. Since the generation of bremsstrahlung and the transport to the sample preserves the sharp timing of the electron beam, positrons generated inside the entire sample volume by pair production feature a sharp start time stamp for lifetime studies. In addition to the existing technique of in-situ production of positrons inside large (cm3) bulk samples using high-energy photons up to 16 MeV from bremsstrahlung production, granular position-sensitive photon detectors have been employed. The detector system will be described and results for experiments using samples with increasing complexity will be presented. The Lu2SiO5:Ce scintillation crystals allow resolving the total energy to 5.1 % (root-mean-square, RMS) and the annihilation lifetime to 225 ps (RMS). 3-dimensional annihilation lifetime maps have been created in an offline-analysis employing well-known techniques from PET.

Wagner, A.; Anwand, W.; Butterling, M.; Fiedler, F.; Fritz, F.; Kempe, M.; Cowan, T. E.

2014-04-01

7

Study of PRIMAVERA steel samples by positron annihilation spectroscopy technique II - Lifetime measurements  

NASA Astrophysics Data System (ADS)

In the present article, a positron annihilation lifetime technique was used for the study of VVER-440/230 weld materials, manufactured in the frame of the international PRIMAVERA project on microstructural investigation of the irradiated WWER-440 reactor pressure vessel steel. The present results complement our previous report of positron angular correlation experiments and provide in-depth characterization of vacancy type defects behavior under irradiation and thermal treatment. The results give new insight into the previously published atom probe tomography and angular correlation of annihilation radiation studies. The measurements do not show any association of phosphorus or its segregation to the open volume defects investigated by positron annihilation spectroscopy. The embrittlement effects related to the phosphorus seem to be effectively annealed-out during 475 °C thermal treatment and the post annealing microstructure and mechanical properties of the material are consequently affected mostly by agglomerations of vacancy clusters coarsened during thermal treatment.

Krsjak, V.; Grafutin, V.; Ilyukhina, O.; Burcl, R.; Ballesteros, A.; Hähner, P.

2012-02-01

8

Vacancy profile in reverse osmosis membranes studied by positron annihilation lifetime measurements and molecular dynamics simulations  

NASA Astrophysics Data System (ADS)

The positron annihilation technique using a slow positron beam can be used for the study of the vacancy profiles in typical reverse osmosis (RO) membranes. In this study, the vacancy profile in the polyamide membrane that exhibits a high permselectivity between ions and water was studied using the positron annihilation technique and molecular dynamics simulations. Ortho-positronium (o-Ps) lifetimes in the surface region of the membranes were evaluated by using a slow positron beam. The diffusion behavior of Na+ and water in the polyamides was simulated by molecular dynamics (MD) methods using the TSUBAME2 supercomputer at the Tokyo Institute of Technology and discussed with the vacancy profile probed by the o-Ps. The results suggested that the large hydration size of Na+ compared to the vacancy size in the polyamides contributes to the increased diffusivity selectivity of water/Na+ that is related to the NaCl desalination performance of the membrane. Both the hydration size of the ions and the vacancy size appeared to be significant parameters to discuss the diffusivity selectivity of water/ions in typical polyamide membranes.

Shimazu, A.; Goto, H.; Shintani, T.; Hirose, M.; Suzuki, R.; Kobayashi, Y.

2013-06-01

9

Prediction of free-volume-type correlations in glassy chalcogenides from positron annihilation lifetime measurements  

NASA Astrophysics Data System (ADS)

A newly modified correlation equation between defect-related positron lifetime determined within two-state trapping model and radius of corresponding free-volume-type defects was proposed to describe compositional variations in atomic-deficient structure of covalent-bonded chalcogenides like binary As-S/Se glasses. Specific chemical environment of free-volume voids around neighboring network-forming polyhedrons was shown to play a decisive role in this correlation, leading to systematically enhanced volumes in comparison with typical molecular substrates, such as polymers.

Shpotyuk, O.; Ingram, A.; Shpotyuk, M.; Filipecki, J.

2014-11-01

10

Positron lifetime spectroscopy in thin polymer coatings  

NASA Technical Reports Server (NTRS)

Polymer coatings are finding increasing applications in aerospace industry. The effectiveness of coatings depends strongly on their microstructure and adhesion to the substrates. Currently, there is no technique for adequately monitoring the quality of the coatings. We adapted positron lifetime spectroscopy for the investigation of thin coatings. Results of measurements on 0.001-in-thick polyurethane coatings on aluminum and steel substrates and thicker (0.080-in.) self-standing polyurethane discs were compared. In all cases, we find positron lifetime groups centered around 560 ps, corresponding to the presence of 0.9 A exp 3 free volume cells. However, the number of free volume cells in thin coatings is larger, suggesting that the morphology of thin coatings is different from that of bulk polyurethane. These results and their structural implications are discussed.

Singh, Jag J.; Eftekhari, Abe; Sprinkle, Danny R.

1990-01-01

11

Analysis of positron lifetime spectra in polymers  

NASA Technical Reports Server (NTRS)

A new procedure for analyzing multicomponent positron lifetime spectra in polymers was developed. It requires initial estimates of the lifetimes and the intensities of various components, which are readily obtainable by a standard spectrum stripping process. These initial estimates, after convolution with the timing system resolution function, are then used as the inputs for a nonlinear least squares analysis to compute the estimates that conform to a global error minimization criterion. The convolution integral uses the full experimental resolution function, in contrast to the previous studies where analytical approximations of it were utilized. These concepts were incorporated into a generalized Computer Program for Analyzing Positron Lifetime Spectra (PAPLS) in polymers. Its validity was tested using several artificially generated data sets. These data sets were also analyzed using the widely used POSITRONFIT program. In almost all cases, the PAPLS program gives closer fit to the input values. The new procedure was applied to the analysis of several lifetime spectra measured in metal ion containing Epon-828 samples. The results are described.

Singh, Jag J.; Mall, Gerald H.; Sprinkle, Danny R.

1988-01-01

12

Measurement of the Neutral D Meson Lifetime (charm, Tasso, Electron-Positron  

NASA Astrophysics Data System (ADS)

The lifetime of the D('0) meson was determined from reconstructed vertices of D('0) mesons produced in e('+)e('-) annihilation. The experiment was performed at the e('+)e('-) storage ring PETRA using the TASSO detector, which included a high resoltuion vertex detector designed for the study of short lived particles. The D('0) mesons were selected from a data sample based on an integrated luminosity of 49 pb('-1) containing 8620 hadronic events whose mean center of mass energy of is 42.2 GeV. The D('0) mesons were identified in the reaction D*('+) (--->) D('0) (pi)('+) with the D('0) decaying into K('-)(pi)('+), K(' -)(pi)('+)(pi)('0), and K('-)(pi)('+)(pi)('-)(pi)('+). From fifteen events, the D('0) lifetime was determined by the method of maximum likelihood to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). in good agreement with the existing measurements.

Strom, David Mattill

13

Vacancy migration process in F82H and Fe-Cr binary alloy using positron annihilation lifetime measurement  

NASA Astrophysics Data System (ADS)

Microstructral evolution of electron-irradiated F82H and Fe-8%Cr at 77 K was studied using positron annihilation lifetime measurements. Irradiation-induced vacancies started to migrate at 300 K and 180 K in F82H and Fe-8%Cr, respectively. Solute Cr atoms did not suppress vacancy migration, but they made di-vacancies more stable. Microvoids were not formed by annealing. In F82H, solute atoms acted as trapping site of irradiation-induced defects and annihilation of vacancies and interstitials was facilitated. Pre-existing dislocations and precipitates were also their sinks. These lead to the suppression of microvoids formation. In Fe-8%Cr, small vacancy-type dislocation loops were formed by isochronal annealing test.

Sato, K.; Xu, Q.; Hamaguchi, D.; Huang, S. S.; Yoshiie, T.

2013-06-01

14

Positron lifetime spectrometer using a DC positron beam  

DOEpatents

An entrance grid is positioned in the incident beam path of a DC beam positron lifetime spectrometer. The electrical potential difference between the sample and the entrance grid provides simultaneous acceleration of both the primary positrons and the secondary electrons. The result is a reduction in the time spread induced by the energy distribution of the secondary electrons. In addition, the sample, sample holder, entrance grid, and entrance face of the multichannel plate electron detector assembly are made parallel to each other, and are arranged at a tilt angle to the axis of the positron beam to effectively separate the path of the secondary electrons from the path of the incident positrons.

Xu, Jun; Moxom, Jeremy

2003-10-21

15

Positron lifetime studies in thermoplastic polyimide test specimens  

NASA Technical Reports Server (NTRS)

Positron lifetime measurements were made in two thermoplastic polyimide materials recently developed at Langley. The long component lifetime values in polyimidesulfone samples are 847 + or - 81 Ps (dry) and 764 + or - 91 Ps (saturated). The corresponding values in LARC thermoplastic imides are 1080 + or - 139 Ps (dry) and 711 + or - 96 Ps (saturated). Clearly, the presence of moisture has greater effect on positron lifetime in LARC thermoplastic imides than in the case of polyimidesulfones. This result is consistent with the photomicrographic observations made on frozen water saturated specimens of these materials.

Singh, J. J.; Stclair, T. L.; Holt, W. H.; Mock, W., Jr.

1982-01-01

16

Microstructural Characterization of Thin Polyimide Films by Positron Lifetime Spectroscopy  

NASA Technical Reports Server (NTRS)

Positron lifetimes have been measured in a series of thin aromatic polyimide films. No evidence of positronium formation was observed in any of the films investigated. All test films exhibited only two positron lifetime components, the longer component corresponding to the positrons annihilating at shallow traps. Based on these trapped positron lifetimes, free volume fractions have been calculated for all the films tested. A free volume model has been developed to calculate the dielectric constants of thin polyimide films. The experimental and the calculated values for the dielectric constants of the films tested are in reasonably good agreement. It has been further noted that the presence of bulky CF(sub 3) groups and meta linkages in the polyimide structure results in higher free volume fraction and, consequently, lower dielectric constant values for the films studied.

Eftekhari, A.; St.Clair, A. K.; Stoakley, D. M.; Sprinkle, Danny R.; Singh, J. J.

1996-01-01

17

Moisture dependence of positron lifetime in Kevlar-49  

NASA Technical Reports Server (NTRS)

Because of filamentary character of Kevlar-49 aramid fibers, there is some concern about the moisture uptake and its effect on plastic composites reinforced with Kevlar-49 fibers. As part of continuing studies of positron lifetime in polymers, we have measured positron lifetime spectra in Kevlar-49 fibers as a function of their moisture content. The long lifetime component intensities are rather low, being only of the order of 2-3 percent. The measured values of long component lifetimes at various moisture levels in the specimens are as follows: 2072 +/- 173 ps (dry); 2013 +/- 193 ps (20.7 percent saturation); 1665 +/- 85 ps (25.7 percent saturation); 1745 +/- 257 ps (32.1 percent saturation); and 1772 +/- 217 ps (100 percent saturation). It is apparent that the long component lifetime at first decreases and then increases as the specimen moisture content increases. These results have been compared with those inferred from Epon-815 and Epon-815/K-49 composite data.

Singh, Jag J.; Holt, William H.; Mock, Willis, Jr.

1984-01-01

18

Single shot positron annihilation lifetime spectroscopy D. B. Cassidy,a  

E-print Network

Single shot positron annihilation lifetime spectroscopy D. B. Cassidy,a S. H. M. Deng, H. K. M in positron trapping technology have made possible experimentation with dense interacting positronium gases developed a method to measure positronium lifetimes from a single intense burst of positrons. Our method

Mills, Allen P.

19

Microstructural Characterization of Polymers by Positron Lifetime Spectroscopy  

NASA Technical Reports Server (NTRS)

Positrons provide a versatile probe for monitoring microstructural features of molecular solids. In this paper, we report on positron lifetime measurements in two different types of polymers. The first group comprises polyacrylates processed on earth and in space. The second group includes fully-compatible and totally-incompatible Semi-Interpenetrating polymer networks of thermosetting and thermoplastic polyimides. On the basis of lifetime measurements, it is concluded that free volumes are a direct reflection of physical/electromagnetic properties of the host polymers.

Singh, Jag J.

1996-01-01

20

Slow positron beam generator for lifetime studies  

NASA Technical Reports Server (NTRS)

A slow positron beam generator uses a conductive source residing between two test films. Moderator pieces are placed next to the test film on the opposite side of the conductive source. A voltage potential is applied between the moderator pieces and the conductive source. Incident energetic positrons: (1) are emitted from the conductive source; (2) are passed through test film; and (3) isotropically strike moderator pieces before diffusing out of the moderator pieces as slow positrons, respectively. The slow positrons diffusing out of moderator pieces are attracted to the conductive source which is held at an appropriate potential below the moderator pieces. The slow positrons have to pass through the test films before reaching the conductive source. A voltage is adjusted so that the potential difference between the moderator pieces and the conductive source forces the positrons to stop in the test films. Measurable annihilation radiation is emitted from the test film when positrons annihilate (combine) with electrons in the test film.

Singh, Jag J. (inventor); Eftekhari, Abe (inventor); St.clair, Terry L. (inventor)

1991-01-01

21

Position-resolved Positron Annihilation Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

A new method which allows for position-resolved positron lifetime spectroscopy studies in extended volume samples is presented. In addition to the existing technique of in-situ production of positrons inside large (cm3) bulk samples using high-energy photons up to 16 MeV from bremsstrahlung production, granular position-sensitive photon detectors have been employed. A beam of intense bremsstrahlung is provided by the superconducting electron linear accelerator ELBE (Electron Linear Accelerator with high Brilliance and low Emittance) which delivers electron bunches of less than 10 ps temporal width and an adjustable bunch separation of multiples of 38 ns, average beam currents of 1 mA, and energies up to 40 MeV. Since the generation of bremsstrahlung and the transport to the sample preserves the sharp timing of the electron beam, positrons generated inside the entire sample volume by pair production feature a sharp start time stamp for positron annihilation lifetime studies with high timing resolutions and high signal to background ratios due to the coincident detection of two annihilation photons. Two commercially available detectors from a high-resolution medial positron-emission tomography system are being employed with 169 individual Lu2SiO5:Ce scintillation crystals, each. In first experiments, a positron-lifetime gated image of a planar Si/SiO2 (pieces of 12.5 mm × 25 mm size) sample and a 3-D structured metal in Teflon target could be obtained proving the feasibility of a three dimensional lifetime-gated tomographic system.

Wagner, A.; Butterling, M.; Fiedler, F.; Fritz, F.; Kempe, M.; Cowan, T. E.

2013-06-01

22

M Ris-R-433 A Positron Lifetime Study of  

E-print Network

M Risø-R-433 S A Positron Lifetime Study of Properties of Light Particles in Liquids Finn M. Jacobsen Risø National Laboratory, DK-4000 Roskilde, Denmark April 1981 #12;RIS�-R-433 A POSITRON LIFETIME. The positron lifetime technique has been used for study- ing the behaviour of the three light particles

23

Novel System for Potential Nondestructive Material Inspection Using Positron Annihilation Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

A new positron annihilation lifetime spectrometer consisting of a start ?-ray detector, a stop ?-ray detector, a digital oscilloscope, and a positron detector, which is a plastic scintillator coupled to a photomultiplier tube, is described. A 22Na source is placed between the positron detector and a sample to be studied. ?-ray signals related to positrons annihilating in the positron detector are rejected by anti-coincidence processing. Comparison of the positron lifetime spectrum of a steel strip collected with the new system with that collected with a conventional system using two specimens sandwiching the 22Na source shows that accurate positron lifetime measurements are possible with the new system. The new system does not require cutting of the samples and is potentially applicable to truly nondestructive onsite inspection of various materials such as those used in nuclear power plants, aircraft and cars, etc., by positron annihilation lifetime spectroscopy (PALS).

Yamawaki, Masato; Kobayashi, Yoshinori; Hattori, Kanehisa; Watanabe, Yoshihiro

2011-08-01

24

Positron lifetime setup based on DRS4 evaluation board  

NASA Astrophysics Data System (ADS)

A digital positron lifetime setup based on DRS4 evaluation board designed at the Paul Scherrer Institute has been constructed and tested in the Positron annihilation laboratory Slovak University of Technology Bratislava. The high bandwidth, low power consumption and short readout time make DRS4 chip attractive for positron annihilation lifetime (PALS) setup, replacing traditional ADCs and TDCs. A software for PALS setup online and offline pulse analysis was developed with Qt,Qwt and ALGLIB libraries.

Petriska, M.; Sojak, S.; Sluge?, V.

2014-04-01

25

Digitized detection of gamma-ray signals concentrated in narrow time windows for transient positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

A pulsed slow-positron beam generated by an electron linear accelerator was directly used for positron annihilation lifetime spectroscopy without any positron storage devices. A waveform digitizer was introduced to simultaneously capture multiple gamma-ray signals originating from positron annihilation events during a single accelerator pulse. The positron pulse was chopped and bunched with the chopper signals also sent to the waveform digitizer. Time differences between the annihilation gamma-ray and chopper peaks were calculated and accumulated as lifetime spectra in a computer. The developed technique indicated that positron annihilation lifetime spectroscopy can be performed in a 20 ?s time window at a pulse repetition rate synchronous with the linear accelerator. Lifetime spectra of a Kapton sheet and a thermally grown SiO2 layer on Si were successfully measured. Synchronization of positron lifetime measurements with pulsed ion irradiation was demonstrated by this technique.

Kinomura, A.; Suzuki, R.; Oshima, N.; O'Rourke, B. E.; Nishijima, T.; Ogawa, H.

2014-12-01

26

Digitized detection of gamma-ray signals concentrated in narrow time windows for transient positron annihilation lifetime spectroscopy.  

PubMed

A pulsed slow-positron beam generated by an electron linear accelerator was directly used for positron annihilation lifetime spectroscopy without any positron storage devices. A waveform digitizer was introduced to simultaneously capture multiple gamma-ray signals originating from positron annihilation events during a single accelerator pulse. The positron pulse was chopped and bunched with the chopper signals also sent to the waveform digitizer. Time differences between the annihilation gamma-ray and chopper peaks were calculated and accumulated as lifetime spectra in a computer. The developed technique indicated that positron annihilation lifetime spectroscopy can be performed in a 20 ?s time window at a pulse repetition rate synchronous with the linear accelerator. Lifetime spectra of a Kapton sheet and a thermally grown SiO2 layer on Si were successfully measured. Synchronization of positron lifetime measurements with pulsed ion irradiation was demonstrated by this technique. PMID:25554275

Kinomura, A; Suzuki, R; Oshima, N; O'Rourke, B E; Nishijima, T; Ogawa, H

2014-12-01

27

Measurement of the tau lepton lifetime  

Microsoft Academic Search

We measure the ? lepton lifetime with ?+?? pairs in which one or both of the ?'s decays to three charged particles. The data were collected with the CLEO II detector operating at the electron-positron collider CESR at energies on and near the Y(4S). We use displacements of the three-track vertices to determine the ? lifetime. The results is ??

R. Balest; B. H Behrens; K. Cho; M. Daoudi; W. T Ford; M. Lohner; P. Rankin; J. Roy; J. G Smith; J. P Alexander; C. Bebek; B. E Berger; K. Berkelman; K. Bloom; David G Cassel; H. A Cho; D. M Coffman; D. S Crowcroft; M. Dickson; P. S Drell; D. J Dumas; R. Ehrlich; R. Elia; P. Gaidarev; R. S Galik; B. Gittelman; S. W Gray; D. L Hartill; B. K Heltsley; C. D Jones; S. L Jones; J. Kandaswamy; N. Katayama; P. C Kim; D. L Kreinick; Lee T; Liu Y; G. S Ludwig; J. Masui; J. Mevissen; N. B Mistry; C. R Ng; E. Nordberg; J. R Patterson; D. Peterson; D. Riley; A. Soffer; C. Ward; P. Avery; C. Prescott; Yang S; J. Yelton; G. Brandenburg; R. A Briere; Liu T; M. Saulnier; R. Wilson; H. Yamamoto; T. E Browder; Li F; J. L Rodriguez; T. Bergfeld; B. I. Eisenstein; J. Ernst; G. E Gladding; G. D Gollin; I. Karliner; M. Palmer; M. Selen; J. J. Thaler; K. W Edwards; K. W McLean; M. Ogg; A. Bellerive; D. I. Britton; R. Janicek; B. D. Macfarlane; P. M Patel; B. Spaan; A. J Sadoff; R. Ammar; P. Baringer; A. Bean; D. Besson; D. Coppage; N. Copty; R. Davis; N. Hancock; S. Kotov; I V Kravchenko; N. Kwak; S. Anderson; Y. Kubota; M. Lattery; J. J O'Neill; S. Patton; R. Poling; T. Riehle; A. Smith; V. Savinov; M. S Alam; S. B Athar; I. J Kim; Z. Ling; A. H Mahmood; H. Severini; C. R Sun; S. Timm; F. Wappler; J. E Duboscq; R. Fulton; D. Fujino; K. K. Gan; K. Honscheid; H. Kagan; R. Kass; J. Lee; M. Sung; A. Undrus; C. White; R. Wanke; A. Wolf; M. M. Zoeller; B. Nemati; S. J Richichi; W. R Ross; P. Skubic; M. Wood; M. Bishai; J. Fast; E. Gerndt; J. W Hinson; D. H Miller; E. I. Shibata; I. P. J Shipsey; M. Yurko; L. Gibbons; S. D Johnson; Y. Kwon; S. Roberts; E. H Thorndike; C. P Jessop; K. Lingel; H. Marsiske; M. L Perl; S. F Schaffner; R. Wang; T. E Coan; V. Fadeyev; I. Korolkov; Y. Maravin; I. Narsky; V. Shelkov; R. Stroynowski; J. Staeck; I. Volobouev; J. Ye; M. Artuso; A. Efimov; M. Gao; M. Goldberg; R. Greene; D. He; S. Kopp; G. C Moneti; Y. Mukhin; T. Skwarnicki; S. Stone; Xing X; J. Bartelt; S. E Csorna; V. Jain; S. Marka; A. Freyberger; D. Gibaut; K. Kinoshita; I. C Lai; P. Pomianowski; S. Schrenk; G. Bonvicini; D. Cinabro; B. Barish; M. Chadha; Chan S; G. Eigen; J. S Miller; C O'Grady; M. Schmidtler; J. Urheim; A. J Weinstein; F. Würthwein; D. M Asner; M. Athanas; D. W Bliss; W. S Brower; G San Martin; H. P Paar; J. Gronberg; C. M Korte; D. J Lange; R. Kutschke; S. Menary; R. J Morrison; S. Nakanishi; H. N Nelson; T. K Nelson; C. Qiao; J. D Richman; D. Roberts; A. Ryd; H. Tajima; M. S Witherell; K Kleinknecht; G Quast; J Raab; B Renk; H G Sander; P Van Gemmeren; C Zeitnitz; Jean-Jacques Aubert; A M Bencheikh; C Benchouk; A Bonissent; G Bujosa; D Calvet; J Carr; C A Diaconu; F Etienne; M Thulasidas; D Nicod; P Payre; D Rousseau; M Talby; I Abt; R W Assmann; C Bauer; Walter Blum; D Brown; H Dietl; Friedrich Dydak; G Ganis; C Gotzhein; K Jakobs; H Kroha; G Lütjens; Gerhard Lutz; W Männer; H G Moser; R H Richter; A Rosado-Schlosser; S Schael; Ronald Settles; H C J Seywerd; R Saint-Denis; G Wolf; R Alemany; J Boucrot; O Callot; A Cordier; F Courault; M Davier; L Duflot; J F Grivaz; P Heusse; M Jacquet; D W Kim; F R Le Diberder; J Lefrançois; A M Lutz; G Musolino; I A Nikolic; H J Park; I C Park; M H Schune; S Simion; J J Veillet; I Videau; D Abbaneo; P Azzurri; G Bagliesi; G Batignani; S Bettarini; C Bozzi; G Calderini; M Carpinelli; M A Ciocci; V Ciulli; R Dell'Orso; R Fantechi; I Ferrante; F Fidecaro; L Foà; F Forti; A Giassi; M A Giorgi; A Gregorio; F Ligabue; A Lusiani; P S Marrocchesi; A Messineo; G Rizzo; G Sanguinetti; A Sciabà; P Spagnolo; Jack Steinberger; Roberto Tenchini; G Tonelli; G Triggiani; C Vannini; P G Verdini; J Walsh; A P Betteridge; G A Blair; L M Bryant; F Cerutti; Y Gao; M G Green; D L Johnson; T Medcalf; L M Mir; P Perrodo; J A Strong; V Bertin; David R Botterill; R W Clifft; T R Edgecock; S Haywood; M Edwards; P Maley; P R Norton; J C Thompson; B Bloch-Devaux; P Colas; S Emery; Witold Kozanecki; E Lançon; M C Lemaire; E Locci; B Marx; P Pérez; J Rander; J F Renardy; A Roussarie; J P Schuller; J Schwindling; A Trabelsi; B Vallage; R P Johnson; H Y Kim; A M Litke; M A McNeil; G Taylor; A Beddall; C N Booth; R Boswell; S L Cartwright; F Combley; I Dawson; A Köksal; M Letho; W M Newton; C Rankin; L F Thompson; A Böhrer; S Brandt; G D Cowan; E Feigl; Claus Grupen; G Lutters; J A Minguet-Rodríguez; F Rivera; P Saraiva; L Smolik; F Stephan; M Apollonio; L Bosisio; R Della Marina; G Giannini; B Gobbo; F Ragusa; J E Rothberg; S R Wasserbaech; S R Armstrong; L Bellantoni; P Elmer; Z Feng; D P S Ferguson; S González; J Grahl; J L Harton; O J Hayes; H Hu; P A McNamara; J M Nachtman; W Orejudos; Y B Pan; Y Saadi; M Schmitt; I J Scott; V Sharma; J Turk; A M Walsh; Wu Sau Lan; X Wu; J M Yamartino; M Zheng; G Zobernig

1996-01-01

28

Positron lifetime calculation for the elements of the periodic table.  

PubMed

Theoretical positron lifetime values have been calculated systematically for most of the elements of the periodic table. Self-consistent and non-self-consistent schemes have been used for the calculation of the electronic structure in the solid, as well as different parametrizations for the positron enhancement factor and correlation energy. The results obtained have been studied and compared with experimental data, confirming the theoretical trends. As is known, positron lifetimes in bulk show a periodic behaviour with atomic number. These calculations also confirm that monovacancy lifetimes follow the same behaviour. The effects of enhancement factors used in calculations have been commented upon. Finally, we have analysed the effects that f and d electrons have on positron lifetimes. PMID:21690967

Campillo Robles, J M; Ogando, E; Plazaola, F

2007-04-30

29

PALSfit: A computer program for analysing positron lifetime spectra  

E-print Network

PALSfit: A computer program for analysing positron lifetime spectra Peter Kirkegaard, Jens V. Olsen. Olsen1) , Morten Eldrup2) , and Niels Jørgen Pedersen2) Title: PALSfit: A computer program for analysing) February 2009 Abstract: A Windows based computer program PALSfit has been developed for analysing positron

30

Positron lifetime spectroscopy for investigation of thin polymer coatings  

NASA Technical Reports Server (NTRS)

In the aerospace industry, applications for polymer coatings are increasing. They are now used for thermal control on aerospace structures and for protective insulating layers on optical and microelectronic components. However, the effectiveness of polymer coatings depends strongly on their microstructure and adhesion to the substrates. Currently, no technique exists to adequately monitor the quality of these coatings. We have adapted positron lifetime spectroscopy to investigate the quality of thin coatings. Results of measurements on thin (25-micron) polyurethane coatings on aluminum and steel substrates have been compared with measurements on thicker (0.2-cm) self-standing polyurethane discs. In all cases, we find positron lifetime groups centered around 560 psec, which corresponds to the presence of 0.9-A(exp 3) free-volume cells. However, the number of these free-volume cells in thin coatings is larger than in thick discs. This suggests that some of these cells may be located in the interfacial regions between the coatings and the substrates. These results and their structural implications are discussed in this report.

Singh, Jag J.; Sprinkle, Danny R.; Eftekhari, Abe

1993-01-01

31

Neutron Lifetime Measurements  

SciTech Connect

Precision measurements of neutron beta decay address basic questions in nuclear and particle physics, astrophysics, and cosmology. As the simplest semileptonic decay system, the free neutron plays an important role in understanding the physics of the weak interaction, and improving the precision of the neutron lifetime is fundamental to testing the validity of the theory. The neutron lifetime also directly affects the relative abundance of primordial helium in big bang nucleosynthesis. There are two distinct strategies for measuring the lifetime. Experiments using cold neutrons measure the absolute specific activity of a beam of neutrons by counting decay protons; experiments using confined, ultracold neutrons determine the lifetime by counting neutrons that remain after some elapsed time. The status of the recent lifetime measurements using both of these techniques is discussed.

Nico, J. S. [National Institute of Standards and Technology, Physics Laboratory, Gaithersburg, MD 20899 (United States)

2006-11-17

32

Positron lifetime calculation for the elements of the periodic table  

Microsoft Academic Search

Theoretical positron lifetime values have been calculated systematically for most of the elements of the periodic table. Self-consistent and non-self-consistent schemes have been used for the calculation of the electronic structure in the solid, as well as different parametrizations for the positron enhancement factor and correlation energy. The results obtained have been studied and compared with experimental data, confirming the

J. M. Campillo Robles; E. Ogando; F. Plazaola

2007-01-01

33

The influence of several parameters on the lifetimes and intensities of positron lifetime spectra of metals  

Microsoft Academic Search

The influence of the instrumental time-resolution function and the source-surface spectrum on the lifetimes and intensities\\u000a of positron lifetime spectra is studied by a computer simulation of such spectra. The prompt curve is described not by a sum\\u000a of Gaussian curves but by the convolution of a Gaussian curve with a double-sided exponential. It is shown that the fitted\\u000a lifetimes

W. Puff

1979-01-01

34

Coupled experimental and DFT +U investigation of positron lifetimes in UO2  

NASA Astrophysics Data System (ADS)

We performed positron annihilation spectroscopy measurements on uranium dioxide irradiated with 45 MeV ? particles. The positron lifetime was measured as a function of the temperature in the 15-300 K range. The experimental results were combined with electronic structure calculations of positron lifetimes of vacancies and vacancy clusters in UO2. Neutral and charged defects consisting of from one to six vacancies were studied computationally using the DFT +U method to take into account strong correlations between the 5 f electrons of uranium. The two-component density functional theory with two different fully self-consistent schemes was used to calculate the positron lifetimes. All defects were relaxed taking into account the forces due to the creation of defects and the positron localized in the vacancy. The interpretation of the experimental observations in the light of the DFT + U results and the positron trapping model indicates that neutral VU+2 VO trivacancies (bound Schottky defects) are the predominant defects detected in the 45 MeV ? irradiated UO2 samples. Our results show that the coupling of a precise experimental work and calculations using carefully chosen assumptions is an effective method to bring further insight into the subject of irradiation induced defects in UO2.

Wiktor, Julia; Barthe, Marie-France; Jomard, Gérald; Torrent, Marc; Freyss, Michel; Bertolus, Marjorie

2014-11-01

35

Portable Positron Measurement System (PPMS)  

ScienceCinema

Portable Positron Measurement System (PPMS) is an automated, non-destructive inspection system based on positron annihilation, which characterizes a material's in situatomic-level properties during the manufacturing processes of formation, solidification, and heat treatment. Simultaneous manufacturing and quality monitoring now are possible. Learn more about the lab's project on our facebook site http://www.facebook.com/idahonationallaboratory.

None

2013-05-28

36

Positron annihilation lifetime changes across the structural phase transition in nanocrystalline Fe{sub 2}O{sub 3}  

SciTech Connect

Nanocrystalline samples of {gamma}-Fe{sub 2}O{sub 3} were prepared through chemical routes and the particles were allowed to grow by thermal treatment at different temperatures. {gamma}-Fe{sub 2}O{sub 3} transformed to the {alpha} phase at a temperature relatively lower than that reported for coarse-grained samples. Positron lifetimes were measured in both the phases of the samples and a significant reduction was observed across the transformation. This is attributed to the expected reduction in the unit cell volume and the nature of orientation of the nearest-neighboring atoms around the positron trapping sites. Positrons are basically annihilating from the octahedral vacancy sites in {gamma}-Fe{sub 2}O{sub 3} and the lifetime decreases as the nearest-neighboring atoms increasingly influence the annihilation probability of the positrons when the sample changes to the {alpha} phase. The reduction in the positron lifetime has helped to envisage the onset of the transformation earlier than that indicated by x-ray diffraction. The positron lifetimes in the intergranular region increased due to the increase in free volume associated with the atoms on the grain surfaces when the grain size reduced. Doppler broadening measurements of the annihilation {gamma}-ray spectral line shapes were also carried out and the results supported these findings.

Chakrabarti, S.; Chaudhuri, S.; Nambissan, P.M.G. [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India); Nuclear and Atomic Physics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)

2005-02-01

37

NEUTRON DAMAGE IN REACTOR PRESSURE-VESSEL STEEL EXAMINED WITH POSITRON ANNIHILATION LIFETIME SPECTROSCOPY  

E-print Network

NEUTRON DAMAGE IN REACTOR PRESSURE-VESSEL STEEL EXAMINED WITH POSITRON ANNIHILATION LIFETIME-vessel steels. We irradiated samples ofASTM A508 nuclear reactor pressure-vessel steel to fast neutron 17 2 (PALS) to study the effects of neutron damage in the steels on positron lifetimes. Non

Motta, Arthur T.

38

Positron annihilation lifetime study of interfaces in ternary polymer blends  

NASA Astrophysics Data System (ADS)

A new method based on positron lifetime spectroscopy is developed to characterize individual interfaces in ternary polymer blends and hence determine the composition dependent miscibility level. The method owes its origin to the Kirkwood-Risemann-Zimm (KRZ) model for the evaluation of the hydrodynamic interaction parameters (?ij) which was used successfully for a binary blend with a single interface. The model was revised for the present work for ternary polymer blends to account for three interfaces. The efficacy of this method is shown for two ternary blends namely poly(styrene-co-acrylonitrile)/poly (ethylene-co-vinylacetate)/poly(vinyl chloride) (SAN/EVA/PVC) and polycaprolactone /poly(styrene-co-acrylonitrile)/poly(vinyl chloride) (PCL/SAN/PVC) at different compositions. An effective hydrodynamic interaction parameter, ?eff, was introduced to predict the overall miscibility of ternary blends.

Meghala, D.; Ramya, P.; Pasang, T.; Raj, J. M.; Ranganathaiah, C.; Williams, J. F.

2013-06-01

39

Positron Annihilation Measurements of High Temperature Superconductors  

NASA Astrophysics Data System (ADS)

The temperature dependence of positron annihilation parameters has been measured for basic YBCO, Dy-doped, and Pr-doped superconducting compounds. The physical properties, such as crystal structure, electrical resistance, and critical temperature, have been studied for all samples. In the basic YBCO and Dy-doped samples, the defect -related lifetime component tau_{2 } was approximately constant from room temperature to above the critical temperature and then showed a step -like decrease in the temperature range 90K { ~} 40K. No significant temperature dependence was found in the short- and long-lifetime components, tau_{1} and tau_{3}. The x-ray diffraction data showed that the crystal structure of these two samples was almost the same. These results indicated that the electronic structure changed below the critical temperature. No transition was observed in the Pr-doped YBCO sample. The advanced computer program "PFPOSFIT" for positron lifetime analysis was modified to run on the UNIX system of the University of Utah. The destruction of superconductivity with Pr doping may be due to mechanisms such as hole filling or hole localization of the charge carriers and may be related to the valence state of the Pr ion. One-parameter analyses like the positron mean lifetime parameter and the Doppler line shape parameter S also have been studied. It was found that a transition in Doppler line shape parameter S was associated with the superconducting transition temperature in basic YBCO, Dy -doped, and 0.5 Pr-doped samples, whereas no transition was observed in the nonsuperconducting Pr-doped sample. The Doppler results indicate that the average electron momentum at the annihilation sites increases as temperature is lowered across the superconducting transition range and that electronic structure change plays an important role in high temperature superconductivity.

Jung, Kang

1995-01-01

40

Measurement of the pionium lifetime  

E-print Network

We report the progress in the measurement of the pionium lifetime by the DIRAC Collaboration at CERN (PS212). Based on data collected in 2001-2003 on Ni targets we have achieved the precision of 11% in the measurement of the pionium lifetime, which corresponds to the measurement of S-wave pion-pion scattering lengths difference |a0-a2| with the accuracy of 6%.

M. Zhabitsky; for the DIRAC Collaboration

2008-10-17

41

Measurement of the tau lifetime  

SciTech Connect

If the tau lepton couples to the charged weak current with universal strength, its lifetime can be expressed in terms of the muon's lifetime, the ratio of the masses of the muon and the tau, and the tau's branching ratio into e anti nu/sub e/ nu/sub tau/ as tau/sub tau/ = tau/sub ..mu../ (m/sub ..mu..//m/sub tau/)/sup 5/ B(tau ..-->.. e anti nu/sub e/nu/sub tau/) = 2.8 +- 0.2 x 10/sup -13/ s. This paper describes the measurement of the tau lifetime made by the Mark II collaboration, using a new high precision drift chamber in contunction with the Mark II detector at PEP. The results of other tau lifetime measurements are summarized.

Jaros, J.A.

1982-10-01

42

Z .Applied Surface Science 149 1999 97102 Unfolding positron lifetime spectra with neural networks  

E-print Network

Z .Applied Surface Science 149 1999 97­102 Unfolding positron lifetime spectra with neural networks is based on the use of artificial neural networks ANNs . By using data from simulated positron spectra: Artificial neural networks ANNs ; Amplitudes; Simulation model 1. Introduction Determination of mean

Pázsit, Imre

43

Muon lifetime measurements at PSI  

NASA Astrophysics Data System (ADS)

The Fermi constant, GF, is most precisely determined by the muon lifetime, ??. Calculations of the two-loop terms in the extraction of GF from ?? in the late 1990's and early 2000's reduced the theoretical uncertainty on the extraction by two orders of magnitude and motivated a new generation of muon lifetime experiments. The FAST and MuLan experiments have the most ambitious precision goals, and take place at Paul Scherrer Institute (PSI). Both have released intermediate results, and have compatible final precision goals of 2 ppm and 1 ppm respectively. Their intermediate measurements have improved the world average muon lifetime to ?? = 2.197035 ?s is (8 ppm), and new results at the precision goals are expected in 2010. Although the goals are similar, the experiments have different systematic uncertainties and provide an excellent cross-check on each other.

Webber, David M.

2009-12-01

44

Analytical evidence for quantum states in aqueous vanadium pentoxide with positron lifetime spectroscopy  

E-print Network

The possibility of registration of quantum states, such as the coalescence of droplets in the sol phase of aqueous vanadium pentoxide V$_2$O$_5$, with positron annihilation lifetime spectroscopy is discussed. The decrease of positronium lifetime in the result of the coalescence is explaned.

Elnikova, L V

2009-01-01

45

Analytical evidence for quantum states in aqueous vanadium pentoxide with positron lifetime spectroscopy  

E-print Network

The possibility of registration of quantum states, such as the coalescence of droplets (tactoids) in the sol phase of aqueous vanadium pentoxide V$_2$O$_5$, with positron annihilation lifetime spectroscopy is discussed. The decrease of the long-living positronium (Ps) lifetime term in the result of the coalescence of V$_2$O$_5$ tactoids is predicted.

L. V. Elnikova

2010-04-26

46

Microstructural Characterization of Semi-Interpenetrating Polymer Networks by Positron Lifetime Spectroscopy  

NASA Technical Reports Server (NTRS)

Thermoset and thermoplastic polyimides have complementary physical and mechanical properties. Whereas thermoset polyimides are brittle and generally easier to process, thermoplastic polyimides are tough but harder to process. A combination of these two types of polyimides may help produce polymers more suitable for aerospace applications. Semi-Interpenetrating Polymer Networks (S-IPN) of thermoset LaRC(TM)-RP46 and thermoplastic LaRC(TM)-IA polyimides were prepared in weight percent ratios ranging from 100:0 to 0:100. Positron lifetime measurements were made in these samples to correlate their free volume features with physical and mechanical properties. As expected, positronium atoms are not formed in these samples. The second lifetime component has been used to infer the positron trap dimensions. The 'free volume' goes through a minimum at a ratio of about 50:50, and this suggests that S-IPN samples are not merely solid solutions of the two polymers. These data and related structural properties of the S-IPN samples are discussed.

Singh, Jag J.; Pater, Ruth H.; Eftekhari, Abe

1996-01-01

47

Photon-induced positron annihilation lifetime spectroscopy using ultrashort laser-Compton-scattered gamma-ray pulses  

SciTech Connect

High-energy ultrashort gamma-ray pulses can be generated via laser Compton scattering with 90 Degree-Sign collisions at the UVSOR-II electron storage ring. As an applied study of ultrashort gamma-ray pulses, a new photon-induced positron annihilation lifetime spectroscopy approach has been developed. Ultrashort gamma-ray pulses with a maximum energy of 6.6 MeV and pulse width of 2.2 ps created positrons throughout bulk lead via pair production. Annihilation gamma rays were detected by a BaF{sub 2} scintillator mounted on a photomultiplier tube. A positron lifetime spectrum was obtained by measuring the time difference between the RF frequency of the electron storage ring and the detection time of the annihilation gamma rays. We calculated the response of the BaF{sub 2} scintillator and the time jitter caused by the variation in the total path length of the ultrashort gamma-ray pulses, annihilation gamma rays, and scintillation light using a Monte Carlo simulation code. The positron lifetime for bulk lead was successfully measured.

Taira, Y.; Toyokawa, H.; Kuroda, R. [Research Institute of Instrumentation Frontier, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Yamamoto, N. [Nagoya University Synchrotron Radiation Research Center, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Adachi, M.; Tanaka, S.; Katoh, M. [UVSOR, Institute for Molecular Science, National Institutes of Natural Sciences, Myodaiji-cho, Okazaki, Aichi 444-8585 (Japan)

2013-05-15

48

Photon-induced positron annihilation lifetime spectroscopy using ultrashort laser-Compton-scattered gamma-ray pulses  

NASA Astrophysics Data System (ADS)

High-energy ultrashort gamma-ray pulses can be generated via laser Compton scattering with 90° collisions at the UVSOR-II electron storage ring. As an applied study of ultrashort gamma-ray pulses, a new photon-induced positron annihilation lifetime spectroscopy approach has been developed. Ultrashort gamma-ray pulses with a maximum energy of 6.6 MeV and pulse width of 2.2 ps created positrons throughout bulk lead via pair production. Annihilation gamma rays were detected by a BaF2 scintillator mounted on a photomultiplier tube. A positron lifetime spectrum was obtained by measuring the time difference between the RF frequency of the electron storage ring and the detection time of the annihilation gamma rays. We calculated the response of the BaF2 scintillator and the time jitter caused by the variation in the total path length of the ultrashort gamma-ray pulses, annihilation gamma rays, and scintillation light using a Monte Carlo simulation code. The positron lifetime for bulk lead was successfully measured.

Taira, Y.; Toyokawa, H.; Kuroda, R.; Yamamoto, N.; Adachi, M.; Tanaka, S.; Katoh, M.

2013-05-01

49

Low energy positron flux generator for lifetime studies in thin films  

Microsoft Academic Search

A slow positron flux generator for positron annihilation spectroscopic measurements in thin polymer films is described. The advantages of this generator include operability at room temperature and atmospheric pressure without special test film preparaton requirements.

Jag J. Singh; Terry L. St. Clair; Abe Eftekhari

1991-01-01

50

A slow positron beam generator for lifetime studies  

NASA Technical Reports Server (NTRS)

A slow positron beam generator using well-annealed polycrystalline tungsten moderators and a Na-22 positron source was developed. A 250 micro c source, deposited on a 2.54 micron thick aluminized mylar, is sandwiched between two (2.54 cm x 2.54 cm x 0.0127 cm) tungsten pieces. Two (2.54 cm x 2.54 cm x t cm) test polymer films insulate the two tungsten moderator pieces from the aluminized mylar source holder (t=0.00127 to 0.0127). A potential difference of 10 to 100 volts--depending on the test polymer film thickness (t)--is applied between the tungsten pieces and the source foil. Thermalized positrons diffusing out of the moderator pieces are attracted to the source foil held at an appropriate potential below the moderator pieces. These positrons have to pass through the test polymer films before they can reach the source foil. The potential difference between the moderator pieces and the aluminized mylar is so adjusted as to force the positrons to stop in the test polymer films. Thus the new generator becomes an effective source of positrons for assaying thin polymer films for their molecular morphology.

Singh, Jag J.; Eftekhari, Abe; St.clair, Terry L.

1989-01-01

51

Muon lifetime measurements at PSI  

SciTech Connect

The Fermi constant, G{sub F}, is most precisely determined by the muon lifetime, {tau}{sub {mu}}. Calculations of the two-loop terms in the extraction of G{sub F} from {tau}{sub {mu}} in the late 1990's and early 2000's reduced the theoretical uncertainty on the extraction by two orders of magnitude and motivated a new generation of muon lifetime experiments. The FAST and MuLan experiments have the most ambitious precision goals, and take place at Paul Scherrer Institute (PSI). Both have released intermediate results, and have compatible final precision goals of 2 ppm and 1 ppm respectively. Their intermediate measurements have improved the world average muon lifetime to {tau}{sub {mu}} = 2.197035 {mu}s is (8 ppm), and new results at the precision goals are expected in 2010. Although the goals are similar, the experiments have different systematic uncertainties and provide an excellent cross-check on each other.

Webber, David M. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

2009-12-17

52

Study of bicontinuous phase in (TTAB+pentanol)/water/n-octane reverse micellar system using positron lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

A phase diagram of (TTAB+pentanol)/water/n-octane has been mapped by using optical method. It exhibits a reverse micellar (L2) phase extending over a wide range of concentrations of the constituents. To investigate the fine structure of the L2 phase, a series of (TTAB+pentanol)/n-octane ternary mixtures having initial concentrations of (TTAB+pentanol) (1:1) in n-octane as 35%, 50% and 65% by weight were prepared. In each of these mixtures, positron lifetime measurements were performed as a function of the concentration of water, using a standard lifetime spectrometer. At water concentrations of 11.8%, 8.5% and 8.4% by weight respectively for the above systems, the o-Ps pick-off lifetime ?3 shows an oscillatory behaviour while I3 representing the Ps formation exhibits an abrupt change. These changes in the positron annihilation parameters have been explained on the basis of onset of bicontinuity in the microemulsion phase. The positron annihilation technique thus suggests the existence of droplet-like and bicontinuous structures in the L2 phase which is otherwise considered optically to be a single phase as the system remains clear and isotropic throughout this phase. Supporting evidence has been provided by the electrical conductivity measurements performed in these systems. These results are presented in this paper.

Chandramani Singh, K.; Yadav, R.; Khani, P. H.

2013-06-01

53

Measurement of the ?-lepton lifetime at Belle  

SciTech Connect

The lifetime of the Tau-lepton is measured using the process , where both leptons decay to . The result for the mean lifetime, based on of data collected with the Belle detector at the resonance and below, is . The first measurement of the lifetime difference between and is performed. The upper limit on the relative lifetime difference between positive and negative leptons is at 90% C.L. (That would make sense if ERICA could take RTF....)

Belous, K.; Shapkin, M.; Sokolov, A.; Adachi, I.; Aihara, H.; Asner, David M.; Aulchenko, V.; Bakich, A. M.; Bala, Anu; Bhuyan, Bipul; Bobrov, A.; Bondar, A.; Bonvicini, Giovanni; Bozek, A.; Bracko, Marko; Browder, Thomas E.; Cervenkov, D.; Chekelian, V.; Chen, A.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Cho, K.; Chobanova, V.; Choi, Y.; Cinabro, David A.; Dalseno, J.; Dolezal, Z.; Dutta, Deepanwita; Eidelman, S.; Epifanov, D.; Farhat, H.; Fast, James E.; Ferber, T.; Gaur, Vipin; Ganguly, Sudeshna; Garmash, A.; Gillard, R.; Goh, Y. M.; Golob, B.; Haba, J.; Hara, Takanori; Hayasaka, K.; Hayashii, H.; Hoshi, Y.; Hou, W. S.; Iijima, T.; Inami, K.; Ishikawa, A.; Itoh, R.; Iwashita, T.; Jaegle, Igal; Julius, T.; Kato, E.; Kichimi, H.; Kiesling, C.; Kim, D. Y.; Kim, H. J.; Kim, J. B.; Kim, M. J.; Kim, Y. J.; Kinoshita, Kay; Ko, Byeong Rok; Kodys, P.; Korpar, S.; Krizan, Jean; Krokovny, Pavel; Kuhr, T.; Kuzmin, A.; Kwon, Y. J.; Lange, J. S.; Lee, S. H.; Libby, J.; Liventsev, Dmitri; Lukin, P.; Matvienko, D.; Miyata, H.; Mizuk, R.; Mohanty, G. B.; Mori, T.; Mussa, R.; Nagasaka, Y.; Nakano, E.; Nakao, M.; Nayak, Minakshi; Nedelkovska, E.; Ng, C.; Nisar, N. K.; Nishida, S.; Nitoh, O.; Ogawa, S.; Okuno, S.; Olsen, Stephen L.; Ostrowicz, W.; Pakhlova, Galina; Park, C. W.; Park, H.; Park, H. K.; Pedlar, Todd; Pestotnik, Rok; Petric, Marko; Piilonen, Leo E.; Ritter, M.; Rohrken, M.; Rostomyan, A.; Ryu, S.; Sahoo, Himansu B.; Saito, Tomoyuki; Sakai, Yoshihide; Sandilya, Saurabh; Santel, Daniel; Santelj, Luka; Sanuki, T.; Savinov, Vladimir; Schneider, O.; Schnell, G.; Schwanda, C.; Semmler, D.; Senyo, K.; Seon, O.; Shebalin, V.; Shen, C. P.; Shibata, T. A.; Shiu, Jing-Ge; Shwartz, B.; Sibidanov, A.; Simon, F.; Sohn, Young-Soo; Stanic, S.; Stanic, M.; Steder, M.; Sumiyoshi, T.; Tamponi, Umberto; Tatishvili, Gocha; Teramoto, Y.; Trabelsi, K.; Tsuboyama, T.; Uchida, M.; Uehara, S.; Uglov, T.; Unno, Yuji; Uno, S.; Usov, Y.; Vahsen, Sven E.; Van Hulse, C.; Vanhoefer, P.; Varner, Gary; Varvell, K. E.; Vinokurova, A.; Vorobyev, V.; Wagner, M. N.; Wang, C. H.; Wang, P.; Watanabe, M.; Watanabe, Y.; Williams, K. M.; Won, E.; Yamaoka, J.; Yamashita, Y.; Yashchenko, S.; Yook, Youngmin; Yuan, C. Z.; Zhang, Z. P.; Zhilich, V.; Zupanc, A.

2014-01-23

54

Microstructural characterization of semi-interpenetrating polymer networks by positron lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Thermoset and thermoplastic polyimides have complementary physical/mechanical properties. Whereas thermoset polyimides are brittle and generally easier to process, thermoplastic polyimides are tough but harder to process. It is expected that a combination of these two types of polyimides may help produce polymers more suitable for aerospace applications. Semi-Interpenetrating Polymer Networks (S-IPNs) of thermoset LaRC™-RP46 and thermoplastic LaRC™-IA polyimides were prepared in weight percent ratios ranging from 100:0 to 0:100. Positron lifetime measurements were made in these samples to correlate their free volume features with physical/mechanical properties. As expected, positronium atoms are not formed in these samples. The second life time component has been used to infer the positron trap dimensions. The "free volume" goes through a minimum at about 50:50 ratio, suggesting that S-IPN samples are not merely solid solutions of the two polymers. These data and related structural properties of the S-IPN samples have been discussed in this paper.

Singh, Jag J.; Pater, Ruth H.; Eftekhari, Abe

1998-01-01

55

Positron annihilation spectroscopy with magnetically analyzed beams  

NASA Technical Reports Server (NTRS)

Lifetime measurements with magnetically analyzed positron beams were made in condensed media with uniform and non-uniform properties. As expected, the lifetime values with magnetically analyzed positron beams in uniform targets are similar to those obtained with conventional positron sources. The lifetime values with magnetically analyzed beams in targets which have non-uniform properties vary with positron energy and are different from the conventional positron source derived lifetime values in these targets.

Singh, J. J.; Holt, W. H.; Mock, W., Jr.

1982-01-01

56

Correlation of Gas Permeability in a Metal-Organic Framework MIL-101(Cr)–Polysulfone Mixed-Matrix Membrane with Free Volume Measurements by Positron Annihilation Lifetime Spectroscopy (PALS)  

PubMed Central

Hydrothermally stable particles of the metal-organic framework MIL-101(Cr) were incorporated into a polysulfone (PSF) matrix to produce mixed-matrix or composite membranes with excellent dispersion of MIL-101 particles and good adhesion within the polymer matrix. Pure gas (O2, N2, CO2 and CH4) permeation tests showed a significant increase of gas permeabilities of the mixed-matrix membranes without any loss in selectivity. Positron annihilation lifetime spectroscopy (PALS) indicated that the increased gas permeability is due to the free volume in the PSF polymer and the added large free volume inside the MIL-101 particles. The trend of the gas transport properties of the composite membranes could be reproduced by a Maxwell model. PMID:24957061

Jeazet, Harold B. Tanh; Koschine, Tönjes; Staudt, Claudia; Raetzke, Klaus; Janiak, Christoph

2013-01-01

57

Measurement of the tau lepton lifetime  

Microsoft Academic Search

The mean lifetime of the tau lepton is measured from a sample of Z-->tau+tau- decays observed with the ALEPH detector at LEP in 1989 and 1990. A new technique is applied to the events containing two one-prong decays: the lifetime is measured from the observed correlation between the impact parameters and azimuthal angles of the two charged tracks. The lifetime

D. Decamp; B. Deschizeaux; C. Goy; J.-P. Lees; M.-N. Minard; R. Alemany; F. Ariztizabal; J. M. Crespo; M. Delfino; E. Fernandez; V. Gaitan; Ll. Garrido; Ll. M. Mir; A. Pacheco; A. Pascual; D. Creanza; M. de Palma; A. Farilla; G. Iaselli; G. Maggi; M. Maggi; S. Natali; M. Quattromini; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; Y. Gao; H. Hu; D. Huang; X. Huang; J. Lin; J. Lou; C. Qiao; T. Wang; Y. Xie; D. Xu; R. Xu; J. Zhang; W. Zhao; W. B. Atwood; L. A. T. Bauerdick; E. Blucher; G. Bonvicini; F. Bossi; J. Boudreau; T. H. Burnett; H. Drevermann; R. W. Forty; R. Hagelberg; S. Haywood; J. Hilgart; R. Jacobsen; B. Jost; M. Kasemann; J. Knobloch; E. Lançon; I. Lehraus; T. Lohse; A. Lusiani; M. Martinez; P. Mato; T. Mattison; H. Meinhard; S R Menary; T. Meyer; Adolf G Minten; A. Miotto; R. Miquel; H.-G. Moser; J. Nash; P. Palazzi; J. A. Perlas; F. Ranjard; G. Redlinger; Luigi Rolandi; A E Roth; J E Rothberg; T. Ruan; M. Saich; D. Schlatter; M. Schmelling; W. Tejessy; H. Wachsmuth; W. Wiedenmann; J. Wotschack; Z. Ajaltouni; F. Badaud; M. Bardadin-Otwinowska; A. M. Bencheikh; R. El Fellous; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; J.-C. Montret; D. Pallin; P. Perret; B. Pietrzyk; J. Proriol; F. Prulhière; G. Stimpfl; J. D. Hansen; J. R. Hansen; P. H. Hansen; R. Møllerud; B. S. Nilsson; I. Efthymiopoulos; E. Simopoulou; A. Vayaki; J. Badier; A. Blondel; G. Bonneaud; J. C. Brient; G. Fouque; A. Gamess; J. Harvey; S. Orteu; A. Rosowsky; M. Rumpf; R. Tanaka; H. Videau; D. J. Candlin; M. I. Parsons; E. Veitch; L. Moneta; G. Parrini; M. Corden; C. Georgiopoulos; M. Ikeda; J. Lannutti; D. Levinthal; M. Mermikides; L. Sawyer; S. Wasserbaech; A. Antonelli; R. Baldini; G. Bencivenni; P. Campana; G. Capon; F. Cerutti; V. Chiarella; B. D'Ettorre-Piazzoli; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; L. Passalacqua; M. Pepe-Altarelli; P. Picchi; B. Altoon; O. Boyle; P. Colrain; A. W. Halley; I. Ten Have; J. G. Lynch; W. Maitland; C. Raine; J. M. Scarr; K. Smith; A. S. Thompson; R. M. Turnbull; B. Brandl; O. Braun; R. Geiges; C. Geweniger; P. Hanke; V. Hepp; E. E. Kluge; Y. Maumary; A. Putzer; B. Rensch; A. Stahl; K. Tittel; M. Wunsch; A. T. Belk; R. Beuselinck; D. M. Binnie; W. Cameron; M. Cattaneo; D. J. Colling; P. J. Dornan; S. Dugeay; A. M. Greene; J. F. Hassard; N. M. Lieske; S. J. Patton; D. G. Payne; M. J. Phillips; J. K. Sedgbeer; G. Taylor; I. R. Tomalin; A. G. Wright; P. Girtler; D. Kuhn; G. Rudolph; C. K. Bowdery; T. J. Brodbeck; A. J. Finch; F. Foster; G. Hughes; D. Jackson; N. R. Keemer; M. Nuttall; A. Patel; T. Sloan; S. W. Snow; E. P. Whelan; T. Barczewski; K. Kleinknecht; J. Raab; B. Renk; S. Roehn; H.-G. Sander; H. Schmidt; F. Steeg; S. M. Walther; B. Wolf; J.-J. Aubert; C. Benchouk; V. Bernard; A. Bonissent; J. Carr; P. Coyle; J. Drinkard; F. Etienne; S. Papalexiou; P. Payre; Z. Qian; D. Rousseau; P. Schwemling; M. Talby; S. Adlung; H. Becker; W. Blum; D. Brown; P. Cattaneo; G. Cowan; B. Dehning; H. Dietl; F. Dydak; M. Fernandez-Bosman; T. Hansl-Kozanecka; J. Lauber; G. Lütjens; W. Männer; Y. Pan; R H Richter; Herbert Rotscheidt; J. Schröder; A. S. Schwarz; Ronald Settles; U. Stierlin; U. Stiegler; R. St. Denis; M. Takashima; J. Thomas; G. Wolf; V. Bertin; J. Boucrot; O. Callot; X. Chen; A. Cordier; M. Davier; J.-F. Grivaz; Ph. Heusse; P. Janot; D. W. Kim; F R Le Diberder; J. Lefrançois; A.-M. Lutz; M.-H. Schune; J.-J. Veillet; I. Videau; Z. Zhang; F. Zomer; D. Abbaneo; S. R. Amendolia; G. Bagliesi; G. Batignani; L. Bosisio; U. Bottigli; C. Bradaschia; M. Carpinelli; M. A. Ciocci; R. dell'Orso; I. Ferrante; F. Fidecaro; L. Foà; E. Focardi; F. Forti; C. Gatto; A. Giassi; M. A. Giorgi; F. Ligabue; E. B. Mannelli; P. S. Marrocchesi; A. Messineo; Fabrizio Palla; G. Sanguinetti; Jack Steinberger; Roberto Tenchini; G. Tonelli; G. Triggiani; C. Vannini; A. Venturi; P. G. Verdini; J. Walsh; J. M. Carter; M. G. Green; P. V. March; T. Medacalf; I. S. Quazi; J. A. Strong; L. R. West; T. Wildish; David R Botterill; R. W. Clifft; T. R. Edgecock; M. Edwards; S. M. Fisher; T. J. Jones; P. R. Norton; D. P. Salmon; J. C. Thompson; B. Bloch-Devaux; P. Colas; Witold Kozanecki; M. C. Lemaire; E. Locci; Sotirios S Loucatos; E. Monnier; P. Perez; F. Perrier; J. Rander; J.-F. Renardy; A. Roussarie; J.-P. Schuller; J. Schwindling; D. Si Mohand; B. Vallage; R. P. Johnson; A. M. Litke; J. Wear; John Gavin Ashman; W. Babbage; C. N. Booth; C M Buttar; R. E. Carney; S L Cartwright; F. Combley; F. Hatfield; J. Martin; D. Parker; P. Reeves; L. F. Thompson; E. Barberio; S. Brandt; Claus Grupen; L. Mirabito; U. Schäfer; H. Seywerd; G. Ganis; G. Giannini; B. Gobbo; F. Ragusa; L. Bellantoni; D. Cinabro; J. S. Conway; D. F. Cowen; Z. Feng; D. P. S. Ferguson; J. Grahl; J. L. Harton; R. C. Jared

1992-01-01

58

Void structure in silica glass with different fictive temperatures observed with positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

We examine voids in silica glasses with different fictive temperatures using positron annihilation lifetime spectroscopy. The pick-off annihilation lifetime of ortho-positronium increases with the fictive temperature, Tf, indicating that the void size increases. High Tf leads to high density and low degree of network polymerization so that increasing void size means that the density fluctuation of the silica glass increases with high Tf. Assuming that such density fluctuation causes light scattering, the previously reported Tf dependence of the Rayleigh scattering coefficient can be well explained by the change in void size.

Ono, Madoka; Hara, Kenta; Fujinami, Masanori; Ito, Setsuro

2012-10-01

59

Information on individual interfaces in ternary polymer blends from positron annihilation lifetime studies  

NASA Astrophysics Data System (ADS)

Positron Annihilation Lifetime Spectroscopy has been used to determine the free volume content in the ternary blends of SAN/EVA/PVC. The method of deriving hydrodynamic interaction parameter (?) in binary polymer blends was modified for ternary polymer blend system characterized by three distinct interfaces. Each interface characterized, is associated with an ? and its assertion for the ternary blend are compared with available literature data.

Meghala, D.; Ramya, P.; Pasang, T.; Ravikumar, H. B.; Ranganathaiah, C.

2012-06-01

60

Positron scattering measurements from Krypton and Xenon  

NASA Astrophysics Data System (ADS)

As a part of a comprehensive program of low energy positron scattering, measurements have been made for a variety of scattering processes from the heavier rare gases, krypton and xenon. In the case of positron scattering, there have been large disagreements between different experiments, and experimental and theoretical determinations of scattering cross sections for these targets. A wide range of low energy positron scattering measurements is now possible, thanks to the development of the Surko trap and beam system, which provides a high energy resolution source of positrons [1-3]. The resulting positron beam is magnetised, and techniques developed for measuring cross sections in the magnetic fields mean that a wide range of scattering processes are now able to be investigated with high accuracy. This presentation will present measurements of total scattering, positronium formation and elastic differential scattering for both of these targets. The strongly forward peaked nature of the differential cross sections will be highlighted, especially as it relates to previous disagreements between different experimental measurements of the grand total cross section. In the case of positronium formation, the difference between present measurements and previous studies will also be discussed. [1] T. Murphy and C. M. Surko, Phys. Rev. A 46, 5696 (1992) [2] S. J. Gilbert et al., Appl. Phys. Lett. 70, 1944 (1997) [3] J. P. Sullivan et al. Phys. Rev. A 66, 042708 (2002)

Sullivan, James; Machacek, Joshua; Makochekanwa, Casten; Jones, Adric; Caradonna, Peter; Slaughter, Daniel; Buckman, Stephen; Mueller, Dennis

2012-06-01

61

Free volumes studies in Thymoquinone and Carvone ?-cyclodextrin nanoparticles by positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy is used to study free volume in ?-cyclodextrin with the encapsulation of thymoquinone and S-carvone, in samples covering the guest to host fraction range from 1:0.1 to 1:1. The results clearly indicate the presence of long lifetime components related to Ps-formation. Although the behavior of the two guests is different, in both cases the results indicate the formation of 1:1 cyclodextrin inclusion compounds. Data show that the addition of carvone to ?-cyclodextrin results in a decrease of the o-Ps lifetime corresponding to a reduction of the average radius of cavities from 2.41 Å to 2.29 Å, whereas the addition of thymoquine decreases the radius from 2.57 Å to 2.35 Å. In turn, the intensity varied from 20.55 to 19.20% and from 20.83 to 0.41%, respectively.

Ferreira Marques, M. F.; Gordo, P. M.; Moreira da Silva, A.

2013-06-01

62

Positron lifetime in vacancy-impurity complexes (*) Section d'Etudes des Solides Irradis, Centre d'Etudes Nuclaires, Boite Postale n 6, 92260 Fontenay aux Roses, France  

E-print Network

L-547 Positron lifetime in vacancy-impurity complexes (*) C. Corbel Section d'Etudes des Solides positon. Abstract. 2014 We calculate the positron lifetime in vacancy-solute (Na, Mg, Zn) complexes in Al-550 15 DÃ?CEMBRE 1981,1 Classification Physics Abstracts 78.70B 1. Introduction. - The positron

Boyer, Edmond

63

First measurement of the $?^+?^-$ atom lifetime  

E-print Network

The goal of the DIRAC experiment at CERN (PS212) is to measure the $\\pi^+\\pi^-$ atom lifetime with 10% precision. Such a measurement would yield a precision of 5% on the value of the $S$-wave $\\pi\\pi$ scattering lengths combination $|a_0-a_2|$. Based on part of the collected data we present a first result on the lifetime, $\\tau=[2.91 ^{+0.49}_{-0.62}]\\times 10^{-15}$ s, and discuss the major systematic errors. This lifetime corresponds to $|a_0-a_2|=0.264 ^{+0.033}_{-0.020} m_{\\pi}^{-1}$.

The DIRAC collaboration

2005-05-20

64

Measurements of heavy quark and lepton lifetimes  

SciTech Connect

The PEP/PETRA energy range has proved to be well-suited for the study of the lifetimes of hadrons containing the b and c quarks and the tau lepton for several reasons. First, these states comprise a large fraction of the total interaction rate in e/sup +/e/sup -/ annihilation and can be cleanly identified. Second, the storage rings have operated at high luminosity and so produced these exotic states copiously. And finally, thanks to the interplay of the Fermi coupling strength, the quark and lepton masses, and the beam energy, the expected decay lengths are in the 1/2 mm range and so are comparatively easy to measure. This pleasant coincidence of cleanly identified and abundant signal with potentially large effects has made possible the first measurements of two fundamental weak couplings, tau ..-->.. nu/sub tau/W and b ..-->.. cW. These measurements have provided a sharp test of the standard model and allowed, for the first time, the full determination of the magnitudes of the quark mixing matrix. This paper reviews the lifetime studies made at PEP during the past year. It begins with a brief review of the three detectors, DELCO, MAC and MARK II, which have reported lifetime measurements. Next it discusses two new measurements of the tau lifetime, and briefly reviews a measurement of the D/sup 0/ lifetime. Finally, it turns to measurements of the B lifetime, which are discussed in some detail. 18 references, 14 figures, 1 table.

Jaros, J.A.

1985-02-01

65

Measurements of the b baryon lifetime  

Microsoft Academic Search

Using about 1.5 million hadronic Z decays recorded with the aleph detector, the lifetime of the b baryons has been measured using two independent data samples. From a maximum likelihood fit to the impact parameter distribution of leptons in 519 ??? combinations containing a b baryon sample of 290 decays, the measured b baryon lifetime is ?b—baryon = 1.05?0.11+0.12(stat)±0.09(syst) ps.

Damir Buskulic; David William Casper; I. De Bonis; D. Decamp; P. Ghez; C. Goy; J.-P. Lees; M.-N. Minard; P. Odier; B. Pietrzyk; F. Ariztizabal; M. Chmeissani; J. M. Crespo; I. Efthymiopoulos; E. Fernandez; M. Fernandez-Bosman; V. Gaitan; Ll. Garrido; M. Martinez; S. Orteu; A. Pacheco; C. Padilla; Fabrizio Palla; A. Pascual; J. A. Perlas; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; A. Farilla; G. Gelao; M. Girone; Giuseppe Iaselli; G. Maggi; N. Marinelli; S. Natali; S. Nuzzo; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; Huang X; Lin J; Q. Ouyang; Wang T; Xie Y; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; G. Bonvicini; David G Cassel; M. Cattaneo; P. Comas; P. Coyle; H. Drevermann; A. Engelhardt; Roger W Forty; M. Frank; R. Hagelberg; J. Harvey; R. Jacobsen; P. Janot; B. Jost; J. Knobloch; Ivan Lehraus; M. Maggi; C. Markou; E. B. Martin; P. Mato; H. Meinhard; Adolf G Minten; R. Miquel; T. Oest; P. Palazzi; J. R. Pater; J.-F. Pusztaszeri; F. Ranjard; P E Rensing; Luigi Rolandi; D. Schlatter; M. Schmelling; O. Schneider; W. Tejessy; I. R. Tomalin; A. Venturi; H W Wachsmuth; W. Wiedenmann; T. Wildish; W. Witzeling; J. Wotschack; Ziad J Ajaltouni; Maria Bardadin-Otwinowska; A. Barres; C. Boyer; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J. C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; J.-M. Rossignol; F. Saadi; Tom Fearnley; J. B. Hansen; J. D. Hansen; P. H. Hansen; B. S. Nilsson; A. Kyriakis; Errietta Simopoulou; I. Siotis; Anna Vayaki; K. Zachariadou; A. Blondel; G R Bonneaud; J. C. Brient; P. Bourdon; L. Passalacqua; A. Rougé; M. Rumpf; R. Tanaka; Andrea Valassi; M. Verderi; H L Videau; D. J. Candlin; M. I. Parsons; E. Focardi; G. Parrini; M. Corden; M C Delfino; C H Georgiopoulos; D. E. Jaffe; A. Antonelli; G. Bencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; V. Chiarella; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; M. Pepe-Altarelli; S. J. Dorris; A. W. Halley; I. ten Have; I. G. Knowles; J. G. Lynch; W. T. Morton; V. O'Shea; C. Raine; P. Reeves; J. M. Scarr; K. Smith; M. G. Smith; A. S. Thompson; F. Thomson; S. Thorn; R. M. Turnbull; U. Becker; O. Braun; C. Geweniger; G. Graefe; P. Hanke; V. Hepp; E. E. Kluge; A. Putzer; B. Rensch; M. Schmidt; J. Sommer; H. Stenzel; K. Tittel; S. Werner; M. Wunsch; R. Beuselinck; David M Binnie; W. Cameron; D. J. Colling; Peter J Dornan; N P Konstantinidis; L. Moneta; A. Moutoussi; J. Nash; G. San Martin; J. K. Sedgbeer; A. M. Stacey; G. Dissertori; P. Girtler; E. Kneringer; D. Kuhn; G. Rudolph; C. K. Bowdery; T. J. Brodbeck; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; Terence Sloan; E. P. Whelan; M. I. Williams; A. Galla; A. M. Greene; K. Kleinknecht; G. Quast; J. Raab; B. Renk; H.-G. Sander; R. Wanke; C. Zeitnitz; Jean-Jacques Aubert; A. M. Bencheikh; C. Benchouk; A. Bonissent; G. Bujosa; D. Calvet; J. Carr; C A Diaconu; F. Etienne; M. Thulasidas; D. Nicod; P. Payre; D. Rousseau; M. Talby; I. Abt; R W Assmann; C. Bauer; Walter Blum; D. Brown; H. Dietl; Friedrich Dydak; G. Ganis; C. Gotzhein; K. Jakobs; H. Kroha; G. Lütjens; Gerhard Lutz; W. Männer; H.-G. Moser; R H Richter; A. Rosado-Schlosser; Ronald Settles; H C J Seywerd; U. Stierlin; R. St. Denis; G. Wolf; R. Alemany; J. Boucrot; O. Callot; A. Cordier; F. Courault; M. Davier; L. Duflot; J.-F. Grivaz; Ph. Heusse; M. Jacquet; D. W. Kim; F R Le Diberder; J. Lefrançois; A.-M. Lutz; G. Musolino; I A Nikolic; H. J. Park; I. C. Park; M.-H. Schune; S. Simion; J.-J. Veillet; I. Videau; D. Abbaneo; P. Azzurri; G. Bagliesi; G. Batignani; S. Bettarini; C. Bozzi; G. Calderini; M. Carpinelli; M. A. Ciocci; V. Ciulli; R. Dell'Orso; R. Fantechi; I. Ferrante; L. Foà; F. Forti; D. Gambino; A. Giassi; M. A. Giorgi; A. Gregorio; F. Ligabue; A. Lusiani; P. S. Marrocchesi; A. Messineo; G. Rizzo; G. Sanguinetti; A. Sciabà; P. Spagnolo; Jack Steinberger; Roberto Tenchini; G. Tonelli; G. Triggiani; C. Vannini; P. G. Verdini; J. Walsh; A. P. Betteridge; G. A. Blair; L. M. Bryant; F. Cerutti; Y. Gao; M. G. Green; D. L. Johnson; T. Medcalf; L. M. Mir; P. Perrodo; J. A. Strong; V. Bertin; David R Botterill; R. W. Clifft; T. R. Edgecock; S. Haywood; M. Edwards; P. Maley; P. R. Norton; J. C. Thompson; B. Bloch-Devaux; P. Colas; H. Duarte; S. Emery; Witold Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; B. Marx; P. Perez; J. Rander; J.-F. Renardy; A. Rosowsky; A. Roussarie; J.-P. Schuller; J. Schwindling; D. Si Mohand; A. Trabelsi; B. Vallage; R. P. Johnson; H. Y. Kim; A. M. Litke; M. A. McNeil; G. Taylor; A. Beddall; C. N. Booth; R. Boswell; S L Cartwright; F. Combley; I. Dawson; A. Koksal; M. Letho; W. M. Newton; C. Rankin; L. F. Thompson; A. Böhrer; S. Brandt; G D Cowan; E. Feigl; Claus Grupen; G. Lutters; J A Minguet-Rodríguez

1995-01-01

66

Effect of rare earth substitutions on some physical properties of Mn–Zn ferrite studied by positron annihilation lifetime spectroscopy  

Microsoft Academic Search

Mn–Zn ferrite substituted with rare earth ions have been investigated by means of positron annihilation lifetime spectroscopy (PALS). The variations of lifetime parameters ?av, I2, and ? with ionic radius of rare earth ions, grain size and electrical resistivity for all samples have been studied. The intergranular pores increase with increasing the ionic radius of rare earth ions and grain

A. M. Samy; N. Mostafa; E. Gomaa

2006-01-01

67

Dark matter annihilations and decays after the AMS-02 positron measurements  

E-print Network

The AMS-02 collaboration has recently presented measurements of excellent quality of the cosmic electron and positron fluxes as well as the positron fraction. We use the measurements of the positron flux to derive, for the first time, limits on the dark matter annihilation cross section and lifetime for various final states. Working under the well-motivated assumption that a background positron flux exists from spallations of cosmic rays with the interstellar medium and from astrophysical sources, we find strong limits on the dark matter properties which are competitive, although slightly weaker, than those derived from the positron fraction. Specifically, for dark matter particles annihilating only into e+ e- or into mu+ mu-, our limits on the annihilation cross section are stronger than the thermal value when the dark matter mass is smaller than 100 GeV or 60 GeV, respectively.

Alejandro Ibarra; Anna S. Lamperstorfer; Joseph Silk

2014-03-27

68

Photo-degradation of Lexan polycarbonate studied using positron lifetime spectroscopy  

SciTech Connect

The free volume properties of pristine and UV irradiated Lexan polycarbonate have been investigated using Positron Lifetime Spectroscopy (PLS). The decrease in o-Ps life time and free volume size of irradiated sample is attributed to free volume modification and formation of more stable free radicals. These free radicals are formed due to the breakage of C-O bonds in Lexan polycarbonate after irradiation. This is also supported by the decrease in the intensity of C-O bond after exposure to UV-radiation as studied from Fourier Transform Infrared (FTIR) spectroscopy and it also shows that benzene ring does not undergo any changes after irradiation.

Hareesh, K.; Sanjeev, Ganesh [Microtron Centre, Department of Physics, Mangalore University, Mangalagangotri-574199 (India); Pandey, A. K. [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085 (India); Meghala, D.; Ranganathaiah, C. [Department of Studies in Physics, University of Mysore, Manasagangotri-570006 (India)

2013-02-05

69

Photo-degradation of Lexan polycarbonate studied using positron lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

The free volume properties of pristine and UV irradiated Lexan polycarbonate have been investigated using Positron Lifetime Spectroscopy (PLS). The decrease in o-Ps life time and free volume size of irradiated sample is attributed to free volume modification and formation of more stable free radicals. These free radicals are formed due to the breakage of C-O bonds in Lexan polycarbonate after irradiation. This is also supported by the decrease in the intensity of C-O bond after exposure to UV-radiation as studied from Fourier Transform Infrared (FTIR) spectroscopy and it also shows that benzene ring does not undergo any changes after irradiation.

Hareesh, K.; Pandey, A. K.; Meghala, D.; Ranganathaiah, C.; Sanjeev, Ganesh

2013-02-01

70

Native vacancies in semi-insulating GaAs observed by positron lifetime spectroscopy under photoexcitation  

NASA Astrophysics Data System (ADS)

We have performed positron lifetime experiments under monochromatic illumination in undoped semi-insulating GaAs. A negative vacancy, identified as the Ga vacancy, is observed in darkness. Illumination with 1.42 eV photons below 150 K reveals another type of vacancy, identified as the As vacancy. The As vacancy has a negative charge state above the ionization level at 50+/-5 meV below the conduction band. This level offers a microscopic explanation to the optical near-band-edge absorption. The concentrations of both Ga and As vacancies are between 1015 and 1016 cm-3.

Saarinen, K.; Kuisma, S.; Hautojärvi, P.; Corbel, C.; Leberre, C.

1993-05-01

71

Investigation of microstructural changes in polyetherether-ketone films at cryogenic temperatures by positron lifetime spectroscopy  

NASA Technical Reports Server (NTRS)

Microstructural changes in Polyetherether-ketone (PEEK) films were investigated in the temperature ranges of 23 to -196 C, using Positron Lifetime Spectroscopy (PLS) technique. It was determined that the total free volume decreases by about 46 percent in amorphous PEEK samples and about 36 percent in semicrystalline PEEK samples when they are cooled down from room temperature to liquid nitrogen (LN2) temperature. If this trend in reduction in free volume with decreasing temperature continues, as expected, it is surmised that PEEK will be able to withstand cooling down to liquid hydrogen (LH2) temperature without any detrimental effect on its diffusivity for liquid hydrogen.

Singh, Jag J.; Eftekhari, Abe; St.clair, Terry L.; Sprinkle, Danny R.

1991-01-01

72

Measurement of the F Meson Lifetime.  

NASA Astrophysics Data System (ADS)

A result on the first measurement of the lifetime of the F('(+OR-)) mesons produced in e('+)e('-) annihilations at 29 GeV is presented. These measurements have been made by using a high precision straw-type drift chamber along with the HRS detector at PEP. The data which. were analysed for these measurements corresponds to an integrated luminosity of 145 Pb('-1). The lifetime is measured to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). based on 17 F('(+OR-)) Decays.

Jung, Chang Kee

73

A positron annihilation lifetime spectroscopic study of the corrosion protective properties of epoxy coatings  

SciTech Connect

Positron Annihilation Lifetime Spectroscopy (PALS) was used to measure the free volume cavity sizes and free volume fractions of crosslinked epoxy coatings on steel before and after saturation with liquid water at 23[degrees]C. A direct linear relationship between the equilibrium volume fraction of water absorbed and the dry relative free volume fraction of bisphenol A epoxy coatings was found. The free volume cavity sizes and the number of free volume cavities per unit volume of these epoxies were found to decrease after water saturation. These decreases are ascribed to the occupation of 13-17% of the free volume cavities by 2-4 water molecules per cavity. The free volume cavity size of polyglycol diepoxides was found to increase after water saturation. This increase is ascribed to the expansion of the free volume cavities by water, which is substantiated by the macroscopic swelling observed in these coatings. An inverse, linear relationship between the equilibrium water uptake and the relative free volume fraction of these coatings were observed. This result coupled with the fact that less than one molecule of nitrobenzene was determined to fit into an epoxy free volume cavity, and that nitrobenzene is quite soluble in most of the epoxides, indicates that other factors besides the magnitude of the free volume fraction affect the amount of solvent absorbed by epoxy coatings. The small percentage of free volume occupied by water and the small number of water molecules capable of filling each void of the bisphenol A epoxies after water saturation correlate to the high impedance values and the good corrosion protection of these coatings, suggesting that water passes through these coatings by slow diffusion through the connected free volume cavities in the coating. Increases in the free volume cavity sizes of the polyglycol diepoxides after water saturation correlate to the low impedance and the poor corrosion protection of these coatings.

MacQueen, R.C.

1992-01-01

74

Weibull regression for lifetimes measured with error.  

PubMed

Models are considered in which 'true' lifetimes are generated by a Weibull regression model and measured lifetimes are determined from the true times by certain measurement error models. Adjusted estimators are obtained under one parametric specification. The bias properties of these estimators and standard estimators are compared both theoretically, using small measurement error asymptotics, and by simulation. The standard estimators of regression coefficients, other than the intercept, are bias-robust. The adjusted estimator of the shape parameter removes the bias of the standard estimator. PMID:10214000

Skinner, C J; Humphreys, K

1999-01-01

75

Measurement of the Omega0(c) lifetime  

SciTech Connect

The authors report a precise measurement of the {Omega}{sub c}{sup 0} lifetime. The data were taken by the SELEX (E781) experiment using 600 GeV/c {Sigma}{sup -}, {pi}{sup -} and p beams. The measurement has been made using 83 {+-} 19 reconstructed {Omega}{sub c}{sup 0} in the {Omega}{sup -} {pi}{sup -}{pi}{sup +}{pi}{sup +} and {Omega}{sup -} {pi}{sup +} decay modes. The lifetime of the {Omega}{sub c}{sup 0} is measured to be 65 {+-} 13(stat) {+-} 9(sys) fs.

Iori, M.; Ayan, A.S.; Akgun, U.; Alkhazov, G.; Amaro-Reyes, J.; Atamantchouk, A.G.; Balatz, M.Y.; Blanco-Covarrubias, A.; Bondar, N.F.; Cooper, P.S.; Dauwe, L.J.; /Ball State U. /Bogazici U. /Carnegie Mellon U. /Rio de Janeiro, CBPF /Fermilab /Serpukhov, IHEP /Beijing, Inst. High Energy Phys. /Moscow, ITEP /Heidelberg, Max Planck Inst. /Moscow State U. /St. Petersburg, INP

2007-01-01

76

Trapped Positrons for High-Precision Magnetic Moment Measurements  

E-print Network

Trapped Positrons for High-Precision Magnetic Moment Measurements (Article begins on next page Positrons for High-Precision Magnetic Moment Measurements A thesis presented by Shannon Michelle Fogwell Shannon Michelle Fogwell Hoogerheide Trapped Positrons for High-Precision Magnetic Moment Measurements

Gabrielse, Gerald

77

Measurement of the F-meson lifetime  

Microsoft Academic Search

The lifetime of the F+\\/- meson has been measured to be (3.5+2.4-1.8+\\/-0.9)×10 -13 s by means of the F+\\/--->phipi+\\/- decay mode. The measurement was made with the high resolution spectrometer at the SLAC e+e- storage ring PEP at a center-of-mass energy of 29 GeV.

K. C. Jung; S. Abachi; C. Akerlof; P. Baringer; I. Beltrami; D. Blockus; G. Bonvicini; B. Brabson; J. M. Brom; B. G. Bylsma; J. Chapman; B. Cork; R. Debonte; M. Derrick; D. Errede; K. K. Gan; S. W. Gray; J.-P. Guillaud; N. Harnew; P. Kesten; D. Koltick; P. Kooijman; F. J. Loeffler; J. S. Loos; E. H. Low; R. L. McIlwain; D. I. Meyer; D. H. Miller; B. Musgrave; H. Neal; C. R. Ng; D. Nitz; H. Ogren; L. E. Price; L. K. Rangan; J. Repond; D. R. Rust; J. Schlereth; E. I. Shibata; K. Sugano; R. Thun; T. Trinko; M. Valdata-Nappi; J. M. Weiss; M. Willutzky; D. E. Wood

1986-01-01

78

DLR PSP system intensity and lifetime measurements  

Microsoft Academic Search

DLR started at 1995 with there own PSP activities. A phase of extensive exploration of hard- and software components followed and internal measurements using the intensity and lifetime method which includes spectra, calibration curves, etc. were performed. A repeatability study was made on the DASA HYTEX model, comparing the Inteco OPMS measurements from 1992\\/94 with the now existing DLR PSP

R. H. Engler; C. Klein

1997-01-01

79

Electronic structure calculations of positron lifetimes in SiC: Self-consistent schemes and relaxation effect  

NASA Astrophysics Data System (ADS)

We present electronic structure calculations of positron lifetimes in various neutral and negative monovacancies in 3C and 6H silicon carbide. Self-consistent positron lifetime calculation schemes were used and full defect relaxation due to the creation of the vacancy and the presence of the positron was considered. Formation energies of the various possible charges of the defects were also calculated to predict their detectability in PAS. Lifetimes between 170 ps and 195 ps for VC and between 222 ps and 227 ps for VSi were obtained. Based on these results we propose new interpretations of the experimental PAS signals observed in n-type 3C and 6H-SiC samples.

Wiktor, J.; Jomard, G.; Bertolus, M.

2014-05-01

80

Lifetime Measurements in $^{182,186}$Pt}  

E-print Network

Lifetimes in the yrast bands of the nuclei $^{182,186}$Pt have been measured using the Doppler-shift Recoil Distance technique. The results in both cases {\\em viz.} a sharp increase in B(E2) values at very low spins, may be interpreted as resulting from a mixing between two bands of different quadrupole deformations.

J. C. Walpe; U. Garg; S. Naguleswaran; J. Wei; W. Reviol; I. Ahmad; M. P. Carpenter; T. L. Khoo

2012-04-20

81

A measurement of the tau lepton lifetime  

Microsoft Academic Search

Using tau+tau- pairs in which one tau decays to leptons and the other decays to 3 charged particles we present a high statistics measurement of the tau lepton lifetime. The data used in this analysis were collected with the CLEO detector at CESR and consist of an integrated luminosity of 429 pb-1 taken at, above, and below the Upsilon (4S).

M. Battle; J. Ernst; H. Kroha; S. Roberts; K. Sparks; E. H. Thorndike; C.-H. Wang; R. Stroynowski; M. Artuso; M. Goldberg; N. Horwitz; R. Kennett; G. C. Moneti; F. Muheim; S. Playfer; Y. Rozen; P. Rubin; T. Skwarnicki; S. Stone; M. Thulasidas; W.-M. Yao; G. Zhu; A. V. Bernes; J. Bartelt; S. E. Csorna; Z. Egyed; V. Jain; T. Letson; M. D. Mestayer; P. Sheldon; D. S. Akerib; B. Barish; M. Chadha; D. F. Cowen; G. Eigen; J. S. Miller; J. Urheim; A. J. Weinstein; D. Acosta; G. Masek; B. Ong; H. Paar; M. Sivertz; A. Bean; J. Gronberg; R. Kutschke; S. Menary; R. J. Morrison; H. Nelson; J. Richman; H. Tajima; D. Schmidt; D. Sperka; M. Witherell; M. Procario; M. Daoudi; W. T. Ford; D. R. Johnson; K. Lingel; M. Lohner; P. Rankin; J. G. Smith; J. P. Alexander; C. Bebek; K. Berkelman; D. Besson; T. E. Browder; D. G. Cassel; E. Cheu; D. M. Coffman; P. S. Drell; R. Ehrlich; R. S. Galik; M. Garcia-Sciveres; B. Geiser; B. Gittelman; S. W. Gray; A. M. Halling; D. L. Hartill; B. K. Heltsley; K. Honscheid; C. Jones; J. Kandaswamy; N. Katayama; P. C. Kim; D. L. Kreinick; J. D. Lewis; G. S. Ludwig; J. Masui; J. Mevissen; N. B. Mistry; S. Nandi; C. R. Ng; E. Nordberg; C. O'Grady; J. R. Patterson; D. Peterson; M. Pisharody; D. Riley; M. Sapper; M. Selen; A. Silverman; H. Worden; M. Worris; F. Würthwein; P. Avery; A. Freyberger; J. Rodriguez; R. Stephens; J. Yelton; D. Cinabro; S. Henderson; K. Kinoshita; T. Liu; F. M. Pipkin; M. Saulnier; R. Wilson; J. Wolinski; D. Xiao; H. Yamamoto; A. J. Sadoff; R. Ammar; S. Ball; P. Baringer; D. Coppage; N. Copty; R. Davis; P. Haas; N. Hancock; M. Kelly; N. Kwak; H. Lam; S. Ro; Y. Kubota; M. Lattery; J. K. Nelson; D. Perticone; R. Poling; S. Schrenk; R. Wang; M. S. Alam; I. J. Kim; W. C. Li; B. Nemati; J. J. O'Neill; V. Romero; H. Severini; C. R. Sun; P.-N. Wang; M. M. Zoeller; G. Crawford; R. Fulton; K. K. Gan; T. Jensen; H. Kagan; R. Kass; J. Lee; R. Malchow; F. Morrow; M. Sung; C. White; J. Whitmore; P. Wilson; F. Butler; X. Fu; G. Kalbfleisch; M. Lambrecht; P. Skubic; J. Snow; P.-L. Wang; D. Bortoletto; D. N. Brown; J. Dominick; R. L. McIlwain; T. Miao; D. H. Miller; M. Modesitt; S. F. Schaffner; E. I. Shibata; I. P. J. Shipsey

1992-01-01

82

Measurement of the Bs Meson Lifetime  

Microsoft Academic Search

The lifetime of the Bs meson is measured using the semileptonic decay Bs-->D-sl+nuX. The data sample consists of 19.3 pb-1 of pp¯ collisions at s = 1.8 TeV collected by the Collider Detector at Fermilab during 1992-1993. There are 76+\\/-8 l+D-s signal events where the Ds is identified via the decay D-s-->phipi-, phi-->K+K-. Using these events, the Bs meson lifetime

F. Abe; M. G. Albrow; S. R. Amendolia; D. Amidei; J. Antos; C. Anway-Wiese; G. Apollinari; H. Areti; M. Atac; P. Auchincloss; F. Azfar; P. Azzi; N. Bacchetta; W. Badgett; M. W. Bailey; J. Bao; P. de Barbaro; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Bartalini; G. Bauer; T. Baumann; F. Bedeschi; S. Behrends; S. Belforte; G. Bellettini; J. Bellinger; D. Benjamin; J. Benlloch; J. Bensinger; D. Benton; A. Beretvas; J. P. Berge; S. Bertolucci; A. Bhatti; K. Biery; M. Binkley; F. Bird; D. Bisello; R. E. Blair; C. Blocker; A. Bodek; W. Bokhari; V. Bolognesi; D. Bortoletto; C. Boswell; T. Boulos; G. Brandenburg; C. Bromberg; E. Buckley-Geer; H. S. Budd; K. Burkett; G. Busetto; A. Byon-Wagner; K. L. Byrum; J. Cammerata; C. Campagnari; M. Campbell; A. Caner; W. Carithers; D. Carlsmith; A. Castro; Y. Cen; F. Cervelli; H. Y. Chao; J. Chapman; M.-T. Cheng; G. Chiarelli; T. Chikamatsu; C. N. Chiou; S. Cihangir; A. G. Clark; M. Cobal; M. Contreras; J. Conway; J. Cooper; M. Cordelli; C. Couyoumtzelis; D. Crane; J. D. Cunningham; T. Daniels; F. Dejongh; S. Delchamps; S. dell'Agnello; M. dell'Orso; L. Demortier; B. Denby; M. Deninno; P. F. Derwent; T. Devlin; M. Dickson; J. R. Dittmann; S. Donati; R. B. Drucker; A. Dunn; K. Einsweiler; J. E. Elias; R. Ely; E. Engels Jr.; S. Eno; D. Errede; S. Errede; Q. Fan; B. Farhat; I. Fiori; B. Flaugher; G. W. Foster; M. Franklin; M. Frautschi; J. Freeman; J. Friedman; A. Fry; T. A. Fuess; Y. Fukui; S. Funaki; G. Gagliardi; S. Galeotti; M. Gallinaro; A. F. Garfinkel; S. Geer; D. W. Gerdes; P. Giannetti; N. Giokaris; P. Giromini; L. Gladney; D. Glenzinski; M. Gold; J. Gonzalez; A. Gordon; A. T. Goshaw; K. Goulianos; H. Grassmann; A. Grewal; G. Grieco; L. Groer; C. Grosso-Pilcher; C. Haber; S. R. Hahn; R. Handler; R. M. Hans; K. Hara; B. Harral; R. M. Harris; S. A. Hauger; J. Hauser; C. Hawk; J. Heinrich; D. Cronin-Hennessy; R. Hollebeek; L. Holloway; A. Hölscher; S. Hong; G. Houk; P. Hu; B. T. Huffman; R. Hughes; P. Hurst; J. Huston; J. Huth; J. Hylen; M. Incagli; J. Incandela; H. Iso; H. Jensen; C. P. Jessop; U. Joshi; R. W. Kadel; E. Kajfasz; T. Kamon; T. Kaneko; D. A. Kardelis; H. Kasha; Y. Kato; L. Keeble; R. D. Kennedy; R. Kephart; P. Kesten; D. Kestenbaum; R. M. Keup; H. Keutelian; F. Keyvan; D. H. Kim; H. S. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; L. Kirsch; P. Koehn; K. Kondo; J. Konigsberg; S. Kopp; K. Kordas; W. Koska; E. Kovacs; W. Kowald; M. Krasberg; J. Kroll; M. Kruse; S. E. Kuhlmann; E. Kuns; A. T. Laasanen; N. Labanca; S. Lammel; J. I. Lamoureux; T. Lecompte; S. Leone; J. D. Lewis; P. Limon; M. Lindgren; T. M. Liss; N. Lockyer; C. Loomis; O. Long; M. Loreti; E. H. Low; J. Lu; D. Lucchesi; C. B. Luchini; P. Lukens; P. Maas; K. Maeshima; A. Maghakian; P. Maksimovic; M. Mangano; J. Mansour; M. Mariotti; J. P. Marriner; A. Martin; J. A. Matthews; R. Mattingly; P. McIntyre; P. Melese; A. Menzione; E. Meschi; G. Michail; S. Mikamo; M. Miller; R. Miller; T. Mimashi; S. Miscetti; M. Mishina; H. Mitsushio; S. Miyashita; Y. Morita; S. Moulding; J. Mueller; A. Mukherjee; T. Muller; P. Musgrave; L. F. Nakae; I. Nakano; C. Nelson; D. Neuberger; C. Newman-Holmes; L. Nodulman; S. Ogawa; S. H. Oh; K. E. Ohl; R. Oishi; T. Okusawa; C. Pagliarone; R. Paoletti; V. Papadimitriou; J. Patrick; G. Pauletta; M. Paulini; L. Pescara; M. D. Peters; T. J. Phillips; G. Piacentino; M. Pillai; R. Plunkett; L. Pondrom; N. Produit; J. Proudfoot; F. Ptohos; G. Punzi; K. Ragan; F. Rimondi; L. Ristori; M. Roach-Bellino; W. J. Robertson; T. Rodrigo; J. Romano; L. Rosenson; W. K. Sakumoto; D. Saltzberg; A. Sansoni; V. Scarpine; A. Schindler; P. Schlabach; E. E. Schmidt; M. P. Schmidt; O. Schneider; G. F. Sciacca; A. Scribano; S. Segler; S. Seidel; Y. Seiya; G. Sganos; A. Sgolacchia; M. Shapiro; N. M. Shaw; Q. Shen; P. F. Shepard; M. Shimojima; M. Shochet; J. Siegrist; A. Sill; P. Sinervo; P. Singh; J. Skarha; K. Sliwa; D. A. Smith; F. D. Snider; L. Song; T. Song; J. Spalding; L. Spiegel; P. Sphicas; A. Spies; L. Stanco; J. Steele; A. Stefanini; K. Strahl; J. Strait; D. Stuart; G. Sullivan; K. Sumorok; R. L. Swartz Jr.; T. Takahashi; K. Takikawa; F. Tartarelli; W. Taylor; P. K. Teng; Y. Teramoto; S. Tether; D. Theriot; J. Thomas; T. L. Thomas; R. Thun; M. Timko; P. Tipton; A. Titov; S. Tkaczyk; K. Tollefson; A. Tollestrup; J. Tonnison; J. F. de Troconiz; J. Tseng; M. Turcotte; N. Turini; N. Uemura; F. Ukegawa; G. Unal; S. van den Brink; S. Vejcik III; R. Vidal; M. Vondracek; R. G. Wagner; R. L. Wagner; N. Wainer; R. C. Walker; C. H. Wang; G. Wang; J. Wang; M. J. Wang; Q. F. Wang; A. Warburton; G. Watts; T. Watts; R. Webb; C. Wendt; H. Wenzel; W. C. Wester III; T. Westhusing; A. B. Wicklund; E. Wicklund; R. Wilkinson; H. H. Williams; P. Wilson; B. L. Winer; J. Wolinski; D. Y. Wu; X. Wu; J. Wyss; A. Yagil; W. Yao; K. Yasuoka; Y. Ye; G. P. Yeh; P. Yeh; M. Yin; J. Yoh; T. Yoshida; D. Yovanovitch

1995-01-01

83

Lifetime measurements of medium-heavy ? hypernuclei  

NASA Astrophysics Data System (ADS)

We have measured the lifetimes of the weak decay of 12?C, 28?Si, and 56?Fe hypernuclei which were produced via a (?+,K+) reaction at KEK 12-GeV PS. The lifetimes were obtained by direct measurement of the production and decay time of the hypernucleus using a fast timing counter system whose time resolution was about 83 ps. Our results for the lifetimes of 12?C, 28?Si, and ?Fe are 231+/-15, 206+/-11, and 215+/-14 ps, respectively. The lifetimes of 11?B and 27?Al with the application of the gate to the p? state of the formation spectra of 12?C and 28?Si were also determined to be 211+/-13 and 203+/-10 ps. From the present work, it was found that the total decay width saturates according to the hypernuclear mass number even at A~12. This suggests the importance of the proper treatment of the short range nature of the nonmesonic decay of ? hypernuclei.

Park, H.; Bhang, H.; Youn, M.; Hashimoto, O.; Maeda, K.; Sato, Y.; Takahashi, T.; Aoki, K.; Kim, Y. D.; Noumi, H.; Omata, K.; Outa, H.; Sekimoto, M.; Shibata, T.; Hasegawa, T.; Hotchi, H.; Ohta, Y.; Ajimura, S.; Kishimoto, T.

2000-05-01

84

Positron annihilation lifetime spectroscopy of mechanically milled protein fibre powders and their free volume aspects  

NASA Astrophysics Data System (ADS)

The present study reports the fabrication of ultra-fine powders from animal protein fibres such as cashmere guard hair, merino wool and eri silk along with their free volume aspects. The respectively mechanically cleaned, scoured and degummed cashmere guard hair, wool and silk fibres were converted into dry powders by a process sequence: Chopping, Attritor Milling, and Spray Drying. The fabricated protein fibre powders were characterised by scanning electron microscope, particle size distribution and positron annihilation lifetime spectroscopy (PALS). The PALS results indicated that the average free volume size in protein fibres increased on their wet mechanical milling with a decrease in the corresponding intensities leading to a resultant decrease in their fractional free volumes.

Patil, K.; Sellaiyan, S.; Rajkhowa, R.; Tsuzuki, T.; Lin, T.; Smith, S. V.; Wang, X.; Uedono, A.

2013-06-01

85

Effect of OPS Dispersion Method on the Free Volume of Polyurethane by Positron Annihilation Lifetime Spectroscopy (PALS)  

Microsoft Academic Search

The free volume of octaphenyl polyhedral oligomeric silsesquioxane (OPS) modified polyurethane prepared from different dispersion method was investigated using Positron annihilation lifetime spectroscopy (PALS). The relationships of free volume and mechanical property were analyzed. Our results showed that OPS decreased the original free volume hole size and fraction, but varied with the dispersion method. For the sonication dispersion samples, the

Ke-Mei Cheng; Chunrong Tian; Yu Du; Fang He; Jian-Hua Wang; Jie Sun

2012-01-01

86

Sensitiveness of the ratio between monovacancy and bulk positron lifetimes to the approximations used in the calculations: Periodic behaviour  

NASA Astrophysics Data System (ADS)

Positron lifetimes have been calculated in bulk and monovacancies for most of the elements of the periodic table. Self-consistent and non-self-consistent schemes have been used for the calculation of the electronic structure in the solid, as well as different parameterizations for the positron enhancement factor and correlation energy. The ratio between the monovacancy and bulk lifetimes has been analyzed. This ratio shows a periodic behaviour with atomic number in all the calculation methods and it is in agreement with selected experimental data. The ratio shows, in contradiction to previous assumptions, sensitiveness to the approximations used in the calculations. This extensive work has allowed us to study and enlighten features of the theory and computing methods broadly used nowadays in simulating, studying and understanding positronic parameters.

Campillo-Robles, J. M.; Ogando, E.; Plazaola, F.

2012-07-01

87

Free volume of mixed cation borosilicate glass sealants elucidated by positron annihilation lifetime spectroscopy and its correlation with glass properties  

NASA Astrophysics Data System (ADS)

The role of La+3/Sr+2 ratios, which is varied from 0.08 to 5.09, on density, molar volume, packing fraction, free volume, thermal and electrical properties in strontium lanthanum aluminoborosilicate based glass sealants intended for solid oxide fuel cell (SOFC) applications is evaluated. The studies reveal expansion of the glass network evident from increasing molar volume and decreasing packing fraction of glasses with progressive La+3 substitutions. The molecular origin of these macroscopic structural features can be accounted for by the free volume parameters measured from positron annihilation lifetime spectroscopy (PALS). The La+3 induced expanded glass networks show increased number of subnanoscopic voids with larger sizes, as revealed from the ortho-positronium (o-Ps) lifetime and its intensity. A remarkably direct correspondence between the molar volume and fractional free volume trend is established with progressive La2O3 substitution in the glasses. The effect of these structural changes on the glass transition temperature, softening temperature, coefficient of thermal expansion, thermal stability as well as electrical conductivity has been studied.

Ojha, Prasanta K.; Rath, Sangram K.; Sharma, Sandeep K.; Sudarshan, Kathi; Pujari, Pradeep K.; Chongdar, Tapas K.; Gokhale, Nitin M.

2015-01-01

88

Positron annihilation in polypropylene studied by lifetime and coincidence Doppler-broadening spectroscopy  

NASA Astrophysics Data System (ADS)

The momentum density distributions (MDDs) of electrons taking part in the annihilation processes in polypropylene (PP) have been measured by coincidence Doppler-broadening spectroscopy. MDDs at the beginning of measurements to those at the saturation level of Ps formation have been compared in order to follow the possible changes in concentration of carbonyl groups (CG). A high initial CG concentration in PP has been observed, while for antioxidant-containing PP no significant presence of CG has been detected, and no changes have been observed during positron irradiation.

Djourelov, N.; He, C.; Suzuki, T.; Shantarovich, V. P.; Ito, Y.; Kondo, K.; Ito, Y.

2003-12-01

89

Nano-free volume characterization by positron annihilation lifetime technique in flame-retardant poly (vinyl chloride) after thermal treatment  

NASA Astrophysics Data System (ADS)

The flammability tests are performed on flame-retardant poly (vinyl chloride) (FRPVC) material that has been used in cable insulation and jacketing construction for multi-purpose reactor (MPR) at Atomic Energy Authority of Egypt, as well as carbon-black FRPVC (CB-FRPVC) material produced by Egyptian Electrical Cable Company (EECC). The temperature variation of thermal conductivity, thermal expansion coefficients, and nano-size free volumes by means of positron annihilation lifetime (PAL) technique are determined. Correlation of positron annihilation and thermal conductivity has been discussed in terms of phonons as the main heat carriers.

Mohsen, M.; Mostafa, N.; Rashad, S. M.; Ayoub, A.; Salem, E. F.

2007-02-01

90

Clay particles - potential of positron annihilation lifetime spectroscopy (PALS) for studying interlayer spacing  

NASA Astrophysics Data System (ADS)

Characterisation of clays is generally achieved by traditional methods, such as X-ray diffraction (XRD) and transmission electron microscopy (TEM). However, clays are often difficult to characterise due to lack of long-range order, thus these tools are not always reliable. Because interlayer spacing in clays can be adjusted to house molecules, there is growing interest to use these materials for drug delivery. Positron annihilation lifetime spectroscopy (PALS) was examined as an alternative tool to characterise a series of well-known clays. XRD of two layered double hydroxides; MgAl-LDH and MgGd-LDH, natural hectorite, fluoromica and laponite, and their PALS spectra were compared. XRD data was used to calculate the interlayer d- spacing in these materials and results show a decrease in interlayer spacing as the heavy metal ions are substituted for those of large ionic radii. Similar results were obtained for PALS data. This preliminary study suggests PALS has potential as a routine tool for characterising clay particles. Further work will examine the sensitivity and reliability of PALS to percent of metal doping and hydration in clay microstructure.

Fong, N.; Guagliardo, P.; Williams, J.; Musumeci, A.; Martin, D.; Smith, S. V.

2011-01-01

91

Study of Gadolinium-doped cerium oxide by XRD, TG-DTA, impedance analysis, and positron lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

X-ray diffraction, thermogravimetry differential thermal analysis, impedance analysis, and positron lifetime spectroscopy were conducted for Gadolinium-doped cerium oxides (GDC) prepared using oxalate coprecipitation method. XRD revealed the fluorite structure indicating that gadolinium is successfully doped into cerium oxide. Prior to sintering, the vacancy-sized free volume and nanovoid were observed at grain boundaries. The vacancy-sized free volumes shrank with increasing sintering temperatures and finally got dominant.

Ohta, S.; Kosaka, T.; Sato, K.

2010-04-01

92

Detection of Atomic Scale Changes in the Free Volume Void Size of Three-Dimensional Colorectal Cancer Cell Culture Using Positron Annihilation Lifetime Spectroscopy  

PubMed Central

Positron annihilation lifetime spectroscopy (PALS) provides a direct measurement of the free volume void sizes in polymers and biological systems. This free volume is critical in explaining and understanding physical and mechanical properties of polymers. Moreover, PALS has been recently proposed as a potential tool in detecting cancer at early stages, probing the differences in the subnanometer scale free volume voids between cancerous/healthy skin samples of the same patient. Despite several investigations on free volume in complex cancerous tissues, no positron annihilation studies of living cancer cell cultures have been reported. We demonstrate that PALS can be applied to the study in human living 3D cell cultures. The technique is also capable to detect atomic scale changes in the size of the free volume voids due to the biological responses to TGF-?. PALS may be developed to characterize the effect of different culture conditions in the free volume voids of cells grown in vitro. PMID:24392097

Castellanos-Rubio, Ainara; Merida, David; Garcia, Jose Angel; Plaza-Izurieta, Leticia; Fernandez-Jimenez, Nora; Plazaola, Fernando; Bilbao, Jose Ramon

2014-01-01

93

Measurement of Beam Lifetime and Applications for SPEAR3  

SciTech Connect

Beam lifetime studies for the SPEAR3 storage ring are presented. The three lifetime components are separated with lifetime measurements under various combinations of beam currents and fill patterns and vertical scraper scans. Touschek lifetime is studied with rf voltage scans and with the horizontal or vertical scrapers inserted. The measurements are explained with calculations based on the calibrated lattice model. Quantum lifetime measurements are performed with reduced longitudinal and horizontal apertures, respectively, from which we deduce the radiation energy loss down to a few keV per revolution and the horizontal beam size.

Huang, Xiaobiao; Corbett, Jeff; /SLAC

2011-04-05

94

MuLan, a part-per-million measurement of the positive muon lifetime  

NASA Astrophysics Data System (ADS)

We report the results from a part-per-million measurement of the positive muon lifetime ??, and a commensurate determination of the Fermi constant GF, by the MuLan Collaboration. The Fermi constant governs the rates of all weak interaction processes and, together with the fine structure constant ? and the Z-boson mass MZ, fixes the electroweak sector of the Standard Model. Additionally, precise knowledge of the free muon lifetime ?? is necessary for interpreting the results from ongoing lifetime measurements of muonic hydrogen and deuterium atoms. The MuLan experiment was conducted at the Paul Scherrer Institute in Villigen, Switzerland using a pulsed surface muon beam, in-vacuum muon-stopping targets, and a large acceptance, finely segmented, fast timing, scintillator array. The scintillator pulses were recorded by 500 MHz, 8-bit waveform digitizers and stored by a high-speed data acquisition system. A total of ˜10^12 decay positrons from muon stops in both a magnetized iron alloy target and a crystal quartz target were recorded. Thorough studies were conducted of systematic effects from positron pulse pileup, muon spin rotation, and other sources. The measured lifetimes from the two different targets are in excellent agreement and together yield a measurement of ?? to better than 1.3 ppm and a determination of GF to better than 0.8 ppm.

Gorringe, Tim

2010-11-01

95

A continuous time-tagged positron beam and its application to materials research  

Microsoft Academic Search

A time-tagged relativistic positron beam with very low time jitter (? 80 ps with the present setup) has been installed at the Stuttgart pelletron accelerator. A position-sensitive ß+ detector with good angular resolution and small e+ directional straggling supplies the start signal for positron lifetime measurements. The stop signal of the positron lifetime spectrometer based on this ``positron clock'' is

P. Wesolowski; K. Maier; J. Major; A. Seeger; H. Stoll; T. Grund; M. Koch

1992-01-01

96

Lifetime Measurements of Trapped ^232Th^3+  

NASA Astrophysics Data System (ADS)

In recent years, there has been considerable interest in the low lying nuclear isomer state of ^229Th which is only several eV above the nuclear ground state [1]. To date, several groups are taking a variety of approaches to finding and exciting this unique state [2], including the use of trapped Th^3+ ions. Despite this attention, few precise measurements have been made of atomic lifetimes. In this work we present experiments to measure the 6D3/2 and 6D5/2 states using laser cooled ^232Th^3+ confined in a linear Paul trap.[4pt] [1] E. Peik and Chr. Tamm, Europhys. Lett. 61, 181 (2003); V. V. Flambaum, Phys. Rev. Lett. 97, 092502 (2006); B. R. Beck et al., Phys. Rev. Lett. 98, 142501 (2007).[0pt] [2] W. G. Rellergert et al., Phys. Rev. Lett. 104, 200802 (2010); S. G. Porsev et al., Phys. Rev. Lett. 105, 182501 (2010); C. J. Campbell et al., Phys. Rev. Let. 106, 223001 (2011).

Depalatis, Michael; Chapman, Michael

2012-06-01

97

Investigation of the free volume and ionic conducting mechanism of poly(ethylene oxide)-LiClO4 polymeric electrolyte by positron annihilating lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

The positron annihilation lifetime and ionic conductivity are each measured as a function of organophilic rectorite (OREC) content and temperature in a range from 160 K to 300 K. According to the variation of ortho-positronium (o-Ps) lifetime with temperature, the glassy transition temperature is determined. The continuous maximum entropy lifetime (MELT) analysis clearly shows that the OREC and temperature have important effects on o-Ps lifetime and free volume distribution. The experimental results show that the temperature dependence of ionic conductivity obeys the Vogel—Tammann—Fulcher (VTF) and Williams—Landel—Ferry (WLF) equations, implying a free-volume transport mechanism. A linear least-squares procedure is used to evaluate the apparent activation energy related to the ionic transport in the VTF equation and several important parameters in the WLF equation. It is worthwhile to notice that a direct linear relationship between the ionic conductivity and free volume fraction is established using the WLF equation based on the free volume theory for nanocomposite electrolyte, which indicates that the segmental chain migration and ionic migration and diffusion could be explained by the free volume theory.

Gong, Jing; Gong, Zhen-Li; Yan, Xiao-Li; Gao, Shu; Zhang, Zhong-Liang; Wang, Bo

2012-10-01

98

Time Stability in Detectors for a 1 ppm Measurement of the Positive Muon Lifetime  

NASA Astrophysics Data System (ADS)

The MuLan experiment aims to obtain a 1 ppm measurement of the positive muon lifetime. In a 22 ?s measurement period for the muon lifetime there are considerably more muon decays at the start of the time and less near the end. We will determine if this bombardment of positrons will create a time delay within the detectors. A laser pulse is sent to 24 of the 340 detectors used to make the positive muon lifetime fit. The same pulse is also sent to a reference detector that does not go into the lifetime fit. The laser pulses are used to measure the time difference between the reference detector and the 24 detectors used to make the lifetime fit. If the muon bombardment does make a considerable difference, then graphing the mean time difference for a specific detector vs the time in the measurement period will show a slope. For a 1 ppm measurement, we need to make sure the time difference at the beginning of the period is within 2.2 x 10-13 s from the end of the period.

Wolfe, Brett

2007-10-01

99

Defect characterization of ZnBeSe solid solutions by means of positron annihilation and photoluminescence techniques  

Microsoft Academic Search

Defect characterization of as-grown Zn1-xBexSe compound semiconductors was studied by positron lifetime and photoluminescence measurements. We obtain both experimental and theoretical evidence that the bulk lifetime of free positrons decreases linearly with Be alloying. The average positron lifetime increases with the temperature, indicating that both vacancies and negative ions trap positrons. The decomposition of the lifetime spectra shows that the

F. Plazaola; J. Flyktman; K. Saarinen; L. Dobrzynski; F. Firszt; S. Legowski; H. Meczynska; W. Paszkowicz; H. Reniewicz

2003-01-01

100

Confronting recent AMS-02 positron fraction and Fermi-LAT Extragalactic Gamma-Ray Background measurements with gravitino dark matter  

E-print Network

The positron fraction measured by the space-based detectors PAMELA, Fermi-LAT and AMS-02 presents anomalous behaviour as energy increase. In particular AMS-02 observations provide compelling evidence for a new source of positrons and electrons. Its origin is unknown, it can be non-exotic (e.g. pulsars), be dark matter or maybe a mixture. We prove the gravitino of R-parity violating supersymmetric models as this source. As the gravitino is a spin 3/2 particle, it offers particular decay channels. We compute the electron, positron and gamma-ray fluxes produced by each gravitino decay channel as it would be detected at the Earth's position. Combining the flux from the different decay modes we can fit AMS-02 measurements of the positron fraction, as well as the electron and positron fluxes, with a gravitino dark matter mass in the range $1-2$ TeV and lifetime of $\\sim 1.0-0.8\\times 10^{26}$ s. The high statistics measurement of electron and positron fluxes, and the flattering in the behaviour of the positron frac...

Carquin, Edson; Gomez-Vargas, German A; Panes, Boris; Viaux, Nicolas

2015-01-01

101

Measurement of the lifetime of the tau lepton  

Microsoft Academic Search

The lifetime of the tau lepton is measured using data collected in 1994 by the L3 detector at LEP. The precise track position information of the Silicon Microvertex Detector is exploited. The tau lepton lifetime is determined from the signed impact parameter distribution for 30322 tau decays into one charged particle and from the decay length distribution for 3891 tau

M. Acciarri; O. Adriani; M. Aguilar-Benitez; S P Ahlen; B. Alpat; J. Alcaraz; G. Alemanni; James V Allaby; A. Aloisio; G. Alverson; M. G. Alviggi; G. Ambrosi; H. Anderhub; V. P. Andreev; T. Angelescu; F. Anselmo; D. Antreasyan; A. Arefiev; T. Azemoon; T. Aziz; P. Bagnaia; L. Baksay; R. C. Ball; S. Banerjee; K. Banicz; R. Barillère; L. Barone; P. Bartalini; A. Baschirotto; M. Basile; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; S. Bhattacharya; M. Biasini; A. Biland; G. M. Bilei; J. J. Blaising; S. C. Blyth; Gerjan J Bobbink; R K Böck; A. Böhm; B. Borgia; A. Boucham; D. Bourilkov; Maurice Bourquin; D. Boutigny; J. G. Branson; V. Brigljevic; I. C. Brock; A. Buffini; A. Buijs; J. D. Burger; W. J. Burger; J K Busenitz; A O Buytenhuijs; X. D. Cai; M. Campanelli; M. Capell; G. Cara Romeo; M. Caria; G. Carlino; A. M. Cartacci; J. Casaus; G. Castellini; F. Cavallari; N. Cavallo; C. Cecchi; M Cerrada-Canales; F. Cesaroni; M Chamizo-Llatas; A. Chan; Y. H. Chang; U. K. Chaturvedi; M. Chemarin; A. Chen; G. Chen; H. F. Chen; H. S. Chen; M. Chen; G. Chiefari; C. Y. Chien; M. T. Choi; Luisa Cifarelli; F. Cindolo; C. Civinini; I. Clare; R. Clare; H. O. Cohn; G. Coignet; A. P. Colijn; N. Colino; S. Costantini; F. Cotorobai; B. de la Cruz; Akos Csilling; T. S. Dai; R. D'Alessandro; R. de Asmundis; H. De Boeck; A. Degré; K. Deiters; P. Denes; F. Denotaristefani; Daryl DiBitonto; M. Diemoz; D N Van Dierendonck; F. Di Lodovico; C. Dionisi; Michael Dittmar; A. Dominguez; A. Doria; I. Dorne; M. T. Dova; E. Drago; D. Duchesneau; P. Duinker; I. Duran; S. Dutta; S. Easo; Yu V Efremenko; H. El Mamouni; A. Engler; F. J. Eppling; F. C. Erné; J. P. Ernenwein; Pierre Extermann; M. Fabre; R. Faccini; S. Falciano; A. Favara; J. Fay; O. Fedin; Marta Felcini; B. Fenyi; T. Ferguson; D. Fernandez; F. Ferroni; H S Fesefeldt; E. Fiandrini; J. H. Field; Frank Filthaut; P. H. Fisher; G. Forconi; L. Fredj; Klaus Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; S. S. Gau; S. Gentile; J. Gerald; N. Gheordanescu; S. Giagu; S. Goldfarb; J. Goldstein; Z. F. Gong; Andreas Gougas; Giorgio Gratta; M. W. Gruenewald; V. K. Gupta; A. Gurtu; L. J. Gutay; K. Hangarter; B. Hartmann; A. Hasan; D. Hatzifotiadou; T. Hebbeker; A. Hervé; W. C. van Hoek; H. Hofer; H. Hoorani; S. R. Hou; G. Hu; Vincenzo Innocente; H. Janssen; B. N. Jin; L. W. Jones; P. de Jong; I. Josa-Mutuberria; A. Kasser; R. A. Khan; Yu A Kamyshkov; P. Kapinos; J. S. Kapustinsky; Yu Karyotakis; M. Kaur; M. N. Kienzle-Focacci; D. Kim; J. K. Kim; S. C. Kim; Y. G. Kim; W. W. Kinnison; A. Kirkby; D. Kirkby; Jasper Kirkby; D. Kiss; W. Kittel; A. Klimentov; A. C. König; I. Korolko; V F Koutsenko; R. W. Kraemer; W. Krenz; H. Kuijten; A. Kunin; P. Ladron de Guevara; G. Landi; C. Lapoint; K M Lassila-Perini; P. Laurikainen; M. Lebeau; A. Lebedev; P. Lebrun; P. Lecomte; P. Lecoq; P. Le Coultre; J. S. Lee; K. Y. Lee; C. Leggett; J. M. Le Goff; R. Leiste; E. Leonardi; P. Levtchenko; Li Chuan; E H Lieb; W. T. Lin; Frank L Linde; L. Lista; Z. A. Liu; W. Lohmann; E. Longo; W. Lu; Y. S. Lu; K. Lübelsmeyer; C. Luci; D. Luckey; L. Luminari; W. Lustermann; W. G. Ma; M. Maity; G. Majumder; L. Malgeri; A. Malinin; C. Maña; S. Mangla; P A Marchesini; A. Marin; J. P. Martin; F. Marzano; G. G. G. Massaro; D. McNally; S. Mele; L. Merola; M. Meschini; W. J. Metzger; M. von der Mey; Y. Mi; A. Mihul; A. J. W. van Mil; G. Mirabelli; J. Mnich; P. Molnar; B. Monteleoni; R. Moore; S. Morganti; T. Moulik; R. Mount; S. Müller; F. Muheim; E. Nagy; S. Nahn; M. Napolitano; F. Nessi-Tedaldi; H. Newman; A. Nippe; H. Nowak; G. Organtini; R. Ostonen; D. Pandoulas; S. Paoletti; P. Paolucci; H. K. Park; G. Pascale; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; Felicitas Pauss; D. Peach; Y. J. Pei; S. Pensotti; D. Perret-Gallix; S. Petrak; A. Pevsner; D. Piccolo; M. Pieri; J. C. Pinto; P. A. Piroué; E. Pistolesi; V. Plyaskin; M. Pohl; V Pozhidaev; H. Postema; N. Produit; D. Prokofiev; G. Rahal-Callot; P. G. Rancoita; M. Rattaggi; G. Raven; P. Razis; K. Read; D. Ren; M. Rescigno; S. Reucroft; T. van Rhee; S. Riemann; B. C. Riemers; K. Riles; O. Rind; S. Ro; A. Robohm; J. Rodin; F. J. Rodriguez; B. P. Roe; S. Röhner; L. Romero; S. Rosier-Lees; Ph. Rosselet; W. van Rossum; S. Roth; J. A. Rubio; H. Rykaczewski; J. Salicio; E. Sanchez; A. Santocchia; M. E. Sarakinos; S. Sarkar; M. Sassowsky; G. Sauvage; C. Schäfer; V. Schegelsky; S. Schmidt-Kaerst; D. Schmitz; P. Schmitz; M. Schneegans; B. Schoeneich; N. Scholz; H. Schopper; D. J. Schotanus; J. Schwenke; G. Schwering; C. Sciacca; D. Sciarrino; J. C. Sens; L. Servoli; S. Shevchenko; N. Shivarov; V. Shoutko; J. Shukla; E. Shumilov; A. Shvorob; T. Siedenburg; D. Son; A. Sopczak; V. Soulimov; B. Smith; P. Spillantini; M. Steuer

1996-01-01

102

Application of positron annihilation lifetime spectroscopy (PALS) to study the nanostructure in amphiphile self-assembly materials: phytantriol cubosomes and hexosomes.  

PubMed

Self-assembled amphiphile nanostructures of colloidal dimensions such as cubosomes and hexosomes are of interest as delivery vectors in pharmaceutical and nanomedicine applications. Translation would be assisted through a better of understanding of the effects of drug loading on the internal nanostructure, and the relationship between this nanostructure and drug release profile. Positron annihilation lifetime spectroscopy (PALS) is sensitive to local microviscosity and is used as an in situ molecular probe to examine the Q2 (cubosome) ? H2 (hexosome) ? L2 phase transitions of the pharmaceutically relevant phytantriol-water system in the presence of a model hydrophobic drug, vitamin E acetate (VitEA). It is shown that the ortho-positronium lifetime (?) is sensitive to molecular packing and mobility and this has been correlated with the rheological properties of individual lyotropic liquid crystalline mesophases. Characteristic PALS lifetimes for L2 (?4? 4 ns) ? H2 (?4? 4 ns) > Q(2?Pn3m) (?4? 2.2 ns) are observed for the phytantriol-water system, with the addition of VitEA yielding a gradual increase in ? from ?? 2.2 ns for cubosomes to ?? 3.5 ns for hexosomes. The dynamic chain packing at higher temperatures and in the L2 and H2 phases is qualitatively less "viscous", consistent with rheological measurements. This information offers increased understanding of the relationship between internal nanostructure and species permeability. PMID:25459998

Dong, Aurelia W; Fong, Celesta; Waddington, Lynne J; Hill, Anita J; Boyd, Ben J; Drummond, Calum J

2015-01-21

103

Precision measurement of the positive muon lifetime by the MuLan collaboration  

NASA Astrophysics Data System (ADS)

We report the result of a measurement of the positive muon lifetime ?? to one part-per-million (ppm) by the MuLan collaboration using a low-energy pulsed muon beam and a segmented array of plastic scintillators to record over 2×1012 decay positrons. Two different in-vacuum muon-stopping targets were used in separate data-taking periods. The combined result gives ? (MuLan)=2196980.3(2.2) ps (1 ppm). This measurement of the muon lifetime provides the most precise determination of the Fermi constant, GF (MuLan)=1.1663788(7)×10-5 GeV(0.6 ppm), and will be used to extract the capture rates of the negative muon on the proton and the deuteron in the ongoing MuCap and MuSun experiments.

Tishchenko, V.; MuLan Collaboration

2012-04-01

104

Measurement of the Bs(0) lifetime using semileptonic decays.  

PubMed

We report a measurement of the Bs(0) lifetime in the semileptonic decay channel Bs(0) --> Ds- mu+ nuX (and its charge conjugate), using approximately 0.4 fb(-1) of data collected with the D0 detector during 2002-2004. Using 5176 reconstructed Ds- mu+ signal events, we have measured the Bs(0) lifetime to be tau(Bs(0))=1.398+/-0.044(stat)(-0.025)(+0.028)(syst) ps. This is the most precise measurement of the Bs(0) lifetime to date. PMID:17280267

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Askew, A; Asman, B; Jesus, A C S Assis; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Calvet, S; Cammin, J; Caron, S; Carrasco-Lizarraga, M A; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Cousinou, M-C; Cox, B; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Das, M; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Elvira, V D; Eno, S; Ermolov, P; Estrada, J; Evans, H; Evdokimov, A; Evdokimov, V N; Fatakia, S N; Feligioni, L; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jenkins, A; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J M; Kalk, J R; Kappler, S; Karmanov, D; Kasper, J; Katsanos, I; Kau, D; Kaur, R; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Kryemadhi, A; Krzywdzinski, S; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lager, S; Lammers, S; Landsberg, G; Lazoflores, J; Le Bihan, A-C; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Leonidopoulos, C; Lesne, V; Leveque, J; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A-M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; McCarthy, R; McCroskey, R; Meder, D; Melnitchouk, A; Mendes, A; Mendoza, L; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Millet, T; Mitrevski, J; Molina, J; Mondal, N K; Monk, J; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundim, L; Mutaf, Y D; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Oguri, V; Oliveira, N; Oshima, N; Otec, R; y Garzón, G J Otero; Owen, M; Padley, P; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M

2006-12-15

105

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

E-print Network

Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before:the probability of UCN losses from the trap was only 1% of that for neutron beta decay. The neutron lifetime obtained,878.5+/-0.7stat+/-0.3sys s, is the most accurate experimental measurement to date.

A. P. Serebrov; V. E. Varlamov; A. G. Kharitonov; A. K. Fomin; Yu. N. Pokotilovski; P. Geltenbort; I. A. Krasnoschekova; M. S. Lasakov; R. R. Taldaev; A. V. Vassiljev; O. M. Zherebtsov

2009-02-02

106

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

SciTech Connect

Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before: the probability of UCN losses from the trap was only 1% of that for neutron {beta} decay. The neutron lifetime obtained, 878.5{+-}0.7{sub stat}{+-}0.3{sub sys} s, is the most accurate experimental measurement to date.

Serebrov, A. P.; Varlamov, V. E.; Kharitonov, A. G.; Fomin, A. K.; Krasnoschekova, I. A.; Lasakov, M. S.; Taldaev, R. R.; Vassiljev, A. V.; Zherebtsov, O. M. [Petersburg Nuclear Physics Institute, Russian Academy of Sciences, RU-188300 Gatchina, Leningrad District (Russian Federation); Pokotilovski, Yu. N. [Joint Institute for Nuclear Research, RU-141980 Dubna, Moscow Region (Russian Federation); Geltenbort, P. [Institut Max von Laue Paul Langevin, Boite Postal 156, F-38042 Grenoble Cedex 9 (France)

2008-09-15

107

Measurement of the lifetimes of B meson mass eigenstates  

E-print Network

In this dissertation, we present the results of the average lifetime measurements in ..., ..., and ... decays, as well as the results of a time-dependent angular analysis of ... and ... decays. The time-dependent angular ...

Anikeev, Konstantin

2004-01-01

108

Measurement of the ?b- and ?b- baryon lifetimes  

NASA Astrophysics Data System (ADS)

Using a data sample of pp collisions corresponding to an integrated luminosity of 3 fb-1, the ?b- and ?b- baryons are reconstructed in the ?b-?J/??- and ?b-?J/??- decay modes and their lifetimes measured to be

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Esen, S.; Evans, T.; Falabella, A.; Färber, C.; Farinelli, C.; Farley, N.; Farry, S.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gaspar, C.; Gauld, R.; Gavardi, L.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gianì, S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jaton, P.; Jawahery, A.; Jezabek, M.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kelsey, M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.

2014-09-01

109

Lifetime measurement of the 9s level of atomic francium.  

PubMed

We use two-photon resonant excitation and time-correlated single-photon counting techniques on a sample of 210Fr atoms confined and cooled in a magneto-optical trap to measure the lifetime of the 9s excited level. Direct measurement of the decay through the 7P(3/2) level at 851 nm yields a lifetime of 107.53 +/- 0.80 ns. PMID:14587813

Aubin, S; Gomez, E; Orozco, L A; Sprouse, G D

2003-11-01

110

Room-temperature microstructural evolution of electroplated Cu studied by focused ion beam and positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Focused ion beam (FIB) microscopy was used to obtain the time dependent transformation fraction and positron annihilation lifetime spectroscopy (PALS) was employed to analyze the vacancy-type defects in electroplated copper (Cu) during room-temperature microstructrual evolution. It was found that PALS is more sensitive than FIB to show the room-temperature microstructual evolution of electroplated Cu at the first stage of self-annealing. The majority of defects in electroplated Cu are dislocation-bound vacancies and vacancy clusters. Both the size and the concentration of the defects are similar for the two samples at the completion of electroplating. During the incubation time, the mean size of vacancy-type defects increases. After the onset of visible grain growth, the size of vacancy-type defects decreases. The detail evolutions of defects differ with the two samples. The role of the evolution of codeposited species was also discussed.

Yin, K. B.; Xia, Y. D.; Zhang, W. Q.; Wang, Q. J.; Zhao, X. N.; Li, A. D.; Liu, Z. G.; Hao, X. P.; Wei, L.; Chan, C. Y.; Cheung, K. L.; Bayes, M. W.; Yee, K. W.

2008-03-01

111

Nuclear Instruments and Methods in Physics Research. Section B; Microstructural Characterization of Semi-Interpenetrating Polymer Networks by Positron Lifetime Spectroscopy  

NASA Technical Reports Server (NTRS)

Thermoset and thermoplastic polyimides have complementary physical/mechanical properties. Whereas thermoset polyimides are brittle and generally easier to process, thermoplastic polyimides are tough but harder to process. It is expected that a combination of these two types of polyimides may help produce polymers more suitable for aerospace applications. Semi-Interpenetrating Polymer Networks (S-IPNs) of thermoset LaRC(Trademark)-RP46 and thermoplastic LARC(Trademark)-IA polyimides were prepared in weight percent ratios ranging from 100:0 to 0: 100. Positron lifetime measurements were made in these samples to correlate their free volume features with physical/mechanical properties. As expected, positronium atoms are not formed in these samples. The second life time component has been used to infer the positron trap dimensions. The "free volume" goes through a minimum at about 50:50 ratio, suggesting that S-IPN samples are not merely solid solutions of the two polymers. These data and related structural properties of the S-IPN samples have been discussed in this paper.

Singh, Jag J.; Pater, Ruth H.; Eftekhari, Abe

1998-01-01

112

High Efficiency Positron Accumulation for High-Precision Measurements  

E-print Network

Positrons are accumulated within a Penning trap designed to make more precise measurements of the positron and electron magnetic moments. The retractable radioactive source used is weak enough to require no license for handling radioactive material and the radiation dosage one meter from the source gives an exposure several times smaller than the average radiation dose on the earth's surface. The 100 mK trap is mechanically aligned with the 4.2 K superconducting solenoid that produces a 6 tesla magnetic trapping field with a direct mechanical coupling.

Hoogerheide, S Fogwell; Novitski, E; Gabrielse, G

2015-01-01

113

Precision measurement of the ?b(0) baryon lifetime.  

PubMed

The ratio of the ?b(0) baryon lifetime to that of the B(0) meson is measured using 1.0??fb(-1) of integrated luminosity in 7 TeV center-of-mass energy pp collisions at the LHC. The ?b(0) baryon is observed for the first time in the decay mode ?b(0)?J/?pK-, while the B(0) meson decay used is the well known B(0)?J/??+ K- mode, where the ?+ K- mass is consistent with that of the K(*0)(892) meson. The ratio of lifetimes is measured to be 0.976±0.012±0.006, in agreement with theoretical expectations based on the heavy quark expansion. Using previous determinations of the B(0) meson lifetime, the ?b(0) lifetime is found to be 1.482±0.018±0.012??ps. In both cases, the first uncertainty is statistical and the second systematic. PMID:25166658

Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D C; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; Davis, A; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Dogaru, M; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gorbounov, P; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicheur, A; Hicks, E; Hill, D; Hoballah, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Kenyon, I R; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Maratas, J; Marconi, U; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Maurice, E; Mazurov, A; Mc Skelly, B; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mordà, A; Morello, M J; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I

2013-09-01

114

Relative Defect Density Measurements of Laser Shock Peened 316L Stainless Steel Using Positron Annihilation Spectroscopy  

SciTech Connect

The surface of an annealed 316L stainless steel coupon was laser shock peened and Vickers hardness measurements were subsequently taken of its surface. This Vickers hardness data was compared with measurements taken using the technique of positron annihilation Doppler broadening spectroscopy. When compared, a correlation was found between the Vickers hardness data measurements and those made using Doppler broadening spectroscopy. Although materials with a high defect density can cause the S-parameter measurements to saturate, variations in the Sparameter measurements suggest that through further research the Doppler broadening technique could be used as a viable alternative to measuring a material's hardness. In turn, this technique, could be useful in industrial settings where surface hardness and surface defects are used to predict lifetime of components.

Marcus A. Gagliardi; Bulent H. Sencer; A. W. Hunt; Stuart A. Maloy; George T. Gray III

2011-12-01

115

Lifetime measurements and transition probabilities in Mo II  

NASA Astrophysics Data System (ADS)

Lifetimes have been measured using time-resolved laser-induced fluorescence for 16 odd levels in the doublet, quartet and sextet systems of Mo II, with energies in the range 48 000-61 000 cm-1. Absolute transition probabilities and oscillator strengths are determined for 110 UV and visible transitions (208 < ? < 485 nm) from a combination of experimental lifetimes and theoretical branching fractions. The theoretical results are obtained using the HFR method including core polarization effects.

Lundberg, H.; Engström, L.; Hartman, H.; Nilsson, H.; Palmeri, P.; Quinet, P.; Biémont, É.

2010-04-01

116

Direct Measurements of the Lifetime of Heavy Hypernuclei  

E-print Network

The lifetime of a Lambda particle embedded in a nucleus (hypernucleus) decreases from that of free Lambda decay due to the opening of the Lambda N to NN weak decay channel. However, it is generally believed that the lifetime of a hypernucleus attains a constant value (saturation) for medium to heavy hypernuclear masses, yet this hypothesis has been difficult to verify. The present paper reports a direct measurement of the lifetime of medium-heavy hypernuclei produced with a photon-beam from Fe, Cu, Ag, and Bi targets. The recoiling hypernuclei were detected by a fission fragment detector using low-pressure multi-wire proportional chambers. The experiment agrees remarkably well with the only previously-measured single-species heavy-hypernucleus lifetime, that of Fe56_Lambda at KEK, and has significantly higher precision. The experiment disagrees with the measured lifetime of an unknown combination of heavy hypernuclei with 180lifetime decrease.

X. Qiu; L. Tang; A. Margaryan; P. Achenbach; A. Ahmidouch; I. Albayrak; D. Androic; A. Asaturyan; R. Asaturyan; O. Ates; R. Badui; P. Baturin; W. Boeglin; J. Bono; E. Brash; P. Carter; C. Chen; X. Chen; A. Chiba; E. Christy; M. M. Dalton; S. Danagoulian; R. De Leo; D. Doi; M. Elaasar; R. Ent; H. Fenker; Y. Fujii; M. Furic; M. Gabrielyan; L. Gan; F. Garibaldi; D. Gaskell; A. Gasparian; T. Gogami; O. Hashimoto; T. Horn; B. Hu; E. V. Hungerford; M. Jones; H. Kanda; M. Kaneta; M. Kawai; D. Kawama; H. Khanal; M. Kohl; A. Liyanage; W. Luo; K. Maeda; P. Markowitz; T. Maruta; A. Matsumura; V. Maxwell; A. Mkrtchyan; H. Mkrtchyan; S. Nagao; S. N. Nakamura; A. Narayan; C. Neville; G. Niculescu; M. I. Niculescu; A. Nunez; Nuruzzaman; Y. Okayasu; T. Petkovic; J. Pochodzalla; J. Reinhold; V. M. Rodriguez; C. Samanta; B. Sawatzky; T. Seva; A. Shichijo; V. Tadevosyan; N. Taniya; K. Tsukada; M. Veilleux; W. Vulcan; F. R. Wesselmann; S. A. Wood; L. Ya; T. Yamamoto; Z. Ye; K. Yokota; L. Yuan; S. Zhamkochyan; L. Zhu

2013-01-16

117

A New Measurement of the Muon Lifetime with the MuLan Experiment  

NASA Astrophysics Data System (ADS)

Following recent theoretical calculations, the uncertainty on the Fermi coupling constant is now limited by the precision with which the muon lifetime is measured. The current world average uncertainty on the lifetime is 17 ppm. The MuLan experiment is designed to measure the muon lifetime to 1 ppm. To supply muons, a periodic, pulsed muon beam is created. During a 5 ?s ``fill period'', muons are directed to a thin stopping target. A 22 ?s ``measurement period'' follows with the beam ``off'' while the stopped muons decay. A spherical detector surrounding the target detects the decay positrons. A wire chamber with a 10 x10 cm window is used during beam tuning and for regular measurements during data production. An FPGA is used to enable fast readout of the wire chamber. The firmware that controls the FPGA allows for prescaling during the fill period to reduce the data rate. A number of scalar signals are produced that reflect the flux of muons in specific areas of the chamber. This firmware is currently being used in the 2006 data production run. I have been responsible for the FPGA firmware, as well as various analysis studies.

Kunkle, Josh

2006-10-01

118

Measurement and Perturbation of Morphogen Lifetime: Effects on Gradient Shape  

PubMed Central

Protein lifetime is of critical importance for most biological processes and plays a central role in cell signaling and embryonic development, where it impacts the absolute concentration of signaling molecules and, potentially, the shape of morphogen gradients. Early conceptual and mathematical models of gradient formation proposed that steady-state gradients are established by an equilibration between the lifetime of a morphogen and its rates of synthesis and diffusion, though whether gradients in fact reach steady state before being read out is a matter of controversy. In any case, this class of models predicts that protein lifetime is a key determinant of both the time to steady state and the spatial extent of a gradient. Using a method that employs repeated photoswitching of a fusion of the morphogen Bicoid (Bcd) and the photoconvertible fluorescent protein Dronpa, we measure and modify the lifetime of Dronpa-Bcd in living Drosophila embryos. We find that the lifetime of Bcd is dynamic, changing from 50 min before mitotic cycle 14 to 15 min during cellularization. Moreover, by measuring total quantities of Bcd over time, we find that the gradient does not reach steady state. Finally, using a nearly continuous low-level conversion to the dark state of Dronpa-Bcd to mimic the effect of increased degradation, we demonstrate that perturbation of protein lifetime changes the characteristic length of the gradient, providing direct support for a mechanism based on synthesis, diffusion, and degradation. PMID:22004733

Drocco, Jeffrey A.; Grimm, Oliver; Tank, David W.; Wieschaus, Eric

2011-01-01

119

Lifetime measurement of atoms consisting of pi+ and pi- mesons  

E-print Network

The lifetime measurement of pi+pi- atoms (A2pi) with 10% precision provides in a model independent way the difference between the S-wave pion-pion scattering lengths for isospin 0 and 2, |a0 -a2|, with 5% accuracy. The scattering lengths a0 and a2 have been calculated in Chiral Perturbation Theory (ChPT) with a precision better than 2.5%. Therefore, such a measurement will be a sensitive check of the understanding of chiral symmetry breaking in QCD by giving an indication about the value of the quark condensate, an order parameter of QCD. The method of observation and lifetime measurement of A2pi are discussed. Data on A2pi production in Pt, Ni and Ti targets and preliminary results for the lifetime measurement are presented.

V. Yazkov; for the DIRAC Collaboration

2003-10-10

120

Measuring Carrier Lifetime in GaAs by Luminescence  

NASA Technical Reports Server (NTRS)

Luminescence proposed as nondestructive technique for measuring Shockley-Read-Hall (SRH) recombination lifetime GaAs. Sample irradiated, and luminescence escapes through surface. Measurement requires no mechanical or electrical contact with sample. No ohmic contacts or p/n junctions needed. Sample not scrapped after tested.

Von Roos, O.

1986-01-01

121

Measurement of the B0 and B meson lifetimes  

Microsoft Academic Search

The lifetimes of the B0 and B- mesons have been measured with the ALEPH detector at LEP. Semileptonic decays of B0 and B- mesons were partially reconstructed by identifying events containing a lepton with an associated D*+ or D0 meson. The proper time of the B meson was estimated from the measured decay length and the momentum and mass of

D. Buskulic; D. Decamp; C. Goy; J.-P. Lees; M.-N. Minard; B. Mours; B. Pietrzyk; R. Alemany; F. Ariztizabal; P. Comas; J. M. Crespo; M. Delfino; E. Fernandez; M. Fernandez-Bosman; V. Gaitan; Ll. Garrido; T. Mattison; A. Pacheco; C. Padilla; A. Pascual; D. Creanza; M. de Palma; A. Farilla; G. Iaselli; G. Maggi; M. Maggi; S. Natali; S. Nuzzo; M. Quattromini; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; Y. Chai; H. Hu; D. Huang; X. Huang; J. Lin; T. Wang; Y. Xie; D. Xu; R. Xu; J. Zhang; L. Zhang; W. Zhao; L. A. T. Bauerdick; E. Blucher; G. Bonvicini; J. Boudreau; D. Casper; H. Drevermann; R. W. Forty; G. Ganis; C. Gay; R. Hagelberg; J. Harvey; S. Haywood; J. Hilgart; R. Jacobsen; B. Jost; J. Knobloch; I. Lehraus; T. Lohse; A. Lusiani; M. Martinez; P. Mato; H. Meinhard; A. Minten; A. Miotto; R. Miquel; H.-G. Moser; P. Palazzi; J. A. Perlas; J.-F. Pusztaszeri; F. Ranjard; G. Redlinger; L. Rolandi; J. Rothberg; T. Ruan; M. Saich; D. Schlatter; M. Schmelling; F. Sefkow; W. Tejessy; H. Wachsmuth; W. Wiedenmann; T. Wildish; W. Witzeling; J. Wotschack; Z. Ajaltouni; F. Badaud; M. Bardadin-Otwinowska; R. El Fellous; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; J.-C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; F. Prulhière; F. Saadi; T. Fearnley; J. D. Hansen; J. R. Hansen; P. H. Hansen; R. Møllerud; B. S. Nilsson; I. Efthymiopoulos; A. Kyriakis; E. Simopoulou; A. Vayaki; K. Zachariadou; J. Badier; A. Blondel; G. Bonneaud; J. C. Brient; G. Fouque; S. Orteu; A. Rougé; M. Rumpf; R. Tanaka; M. Verderi; H. Videau; D. J. Candlin; M. I. Parsons; E. Veitch; L. Moneta; G. Parrini; M. Corden; C. Georgiopoulos; M. Ikeda; J. Lannutti; D. Levinthal; M. Mermikides; L. Sawyer; S. Wasserbaech; A. Antonelli; R. Baldini; G. Bencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; F. Cerutti; V. Chiarella; B. D'Ettorre-Piazzoli; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; L. Passalacqua; M. Pepe-Altarelli; P. Picchi; P. Colrain; I. Ten Have; J. G. Lynch; W. Maitland; W. T. Morton; C. Raine; P. Reeves; J. M. Scarr; K. Smith; M. G. Smith; A. S. Thompson; R. M. Turnbull; B. Brandl; O. Braun; C. Geweniger; P. Hanke; V. Hepp; E. E. Kluge; Y. Maumary; A. Putzer; B. Rensch; A. Stahl; K. Tittel; M. Wunsch; A. T. Belk; R. Beuselinck; D. M. Binnie; W. Cameron; M. Cattaneo; D. J. Colling; P. J. Dornan; S. Dugeay; A. M. Greene; J. F. Hassard; N. M. Lieske; J. Nash; D. G. Payne; M. J. Phillips; J. K. Sedgbeer; I. R. Tomalin; A. G. Wright; P. Girtler; E. Kneringer; D. Kuhn; G. Rudolph; C. K. Bowdery; T. J. Brodbeck; A. J. Finch; F. Foster; G. Hughes; D. Jackson; N. R. Keemer; M. Nuttall; A. Patel; T. Sloan; S. W. Snow; E. P. Whelan; K. Kleinknecht; J. Raab; B. Renk; H.-G. Sander; H. Schmidt; F. Steeg; S. M. Walther; R. Wanke; B. Wolf; J.-J. Aubert; A. M. Bencheikh; C. Benchouk; A. Bonissent; J. Carr; P. Coyle; J. Drinkard; F. Etienne; D. Nicod; S. Papalexiou; P. Payre; L. Roos; D. Rousseau; P. Schwemling; M. Talby; S. Adlung; R. Assmann; C. Bauer; W. Blum; D. Brown; P. Cattaneo; B. Dehning; H. Dietl; F. Dydak; M. Frank; A. W. Halley; J. Lauber; G. Lütjens; G. Lutz; W. Männer; R. Richter; H. Rotscheidt; J. Schröder; A. S. Schwarz; R. Settles; H. Seywerd; U. Stierlin; U. Stiegler; R. St. Denis; G. Wolf; J. Boucrot; O. Callot; A. Cordier; M. Davier; L. Duflot; J.-F. Grivaz; Ph. Heusse; D. E. Jaffe; P. Janot; D. W. Kim; F. Le Diberder; J. Lefrançois; A.-M. Lutz; M.-H. Schune; J.-J. Veillet; I. Videau; Z. Zhang; D. Abbaneo; G. Bagliesi; G. Batignani; L. Bosisio; U. Bottigli; C. Bozzi; G. Calderini; M. Carpinelli; M. A. Ciocci; R. dell'Orso; I. Ferrante; F. Fidecaro; L. Foà; E. Focardi; F. Forti; A. Giassi; M. A. Giorgi; A. Gregorio; F. Ligabue; E. B. Mannelli; P. S. Marrocchesi; A. Messineo; F. Palla; G. Rizzo; G. Sanguinetti; P. Spagnolo; J. Steinberger; R. Tenchini; G. Tonelli; G. Triggiani; C. Vannini; A. Venturi; P. G. Verdini; J. Walsh; A. P. Betteridge; J. M. Carter; M. G. Green; P. V. March; Ll. M. Mir; T. Medcalf; I. S. Quazi; J. A. Strong; L. R. West; D. R. Botterill; R. W. Clifft; T. R. Edgecock; M. Edwards; S. M. Fisher; T. J. Jones; P. R. Norton; D. P. Salmon; J. C. Thompson; B. Bloch-Devaux; P. Colas; H. Duarte; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; P. Perez; F. Perrier; J. Rander; J.-F. Renardy; A. Rosowsky; A. Roussarie; J.-P. Schuller; J. Schwindling; D. Si Mohand; B. Vallage; R. P. Johnson; A. M. Litke; G. Taylor; J. Wear; J. G. Ashman; W. Babbage; C. N. Booth; C. Buttar; R. E. Carney; S. Cartwright; F. Combley; F. Hatfield; L. F. Thompson; E. Barberio; A. Böhrer; S. Brandt; G. Cowan; C. Grupen; G. Lutters; F. Rivera; U. Schäfer; L. Smolik; R. della Marina; G. Giannini; B. Gobbo; F. Ragusa; L. Bellantoni; W. Chen; D. Cinabro; J. S. Conway; D. F. Cowen; Z. Feng; D. P. S. Ferguson

1993-01-01

122

Measurements of the B +, B 0, meson and baryon lifetimes  

NASA Astrophysics Data System (ADS)

Measurements of b-hadron lifetimes are reported using pp collision data, corresponding to an integrated luminosity of 1.0 fb-1, collected by the LHCb detector at a centre-of-mass energy of 7 TeV. Using the exclusive decays B + ? J/? K +, B 0 ? J/? K ?(892)0, , and the average decay times in these modes are measured to be where the first uncertainty is statistical and the second is systematic. These represent the most precise lifetime measurements in these decay modes. In addition, ratios of these lifetimes, and the ratio of the decay-width difference, ?? d , to the average width, ? d , in the B 0 system, ?? d /? d = -0 .044 ± 0 .025 ± 0 .011, are reported. All quantities are found to be consistent with Standard Model expectations. [Figure not available: see fulltext.

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Callot, O.; Calvi, M.; Gomez, M. Calvo; Camboni, A.; Campana, P.; Perez, D. Campora; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Akiba, K. Carvalho; Casse, G.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Torres, M. Cruz; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dorosz, P.; Suárez, A. Dosil; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Esen, S.; Falabella, A.; Färber, C.; Farinelli, C.; Farry, S.; Ferguson, D.; Albor, V. Fernandez; Rodrigues, F. Ferreira; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furfaro, E.; Torreira, A. Gallas; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Tico, J. Garra; Garrido, L.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Giani', S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Gándara, M. Grabalosa; Diaz, R. Graciani; Cardoso, L. A. Granado; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Hafkenscheid, T. W.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Morata, J. A. Hernando; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Kochebina, O.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lowdon, P.; Lu, H.; Lucchesi, D.; Luisier, J.; Luo, H.; Luppi, E.; Lupton, O.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.

2014-04-01

123

New Millisecond Isomer Lifetime Measurements at LANSCE  

NASA Astrophysics Data System (ADS)

New half-life measurements have been made of the millisecond isomers 71mGe, 114m2I, 208mBi, 88m1Y, 88m2Y, and 75mAs populated in neutron-induced reactions. These measurements were made using the unique time structure of the LANSCE/WNR neutron source, by observing the ?-ray decays of the isomers during the time between the LANSCE proton macropulses. Two different LANSCE proton beam time structures were used. The GEANIE array of HPGe detectors was used to detect the ?-ray decays.

Devlin, M.; Nelson, R. O.; Fotiades, N.; O'Donnell, J. M.

2014-06-01

124

Measurement of the Lifetime Difference between Bs Mass Eigenstates  

Microsoft Academic Search

We present measurements of the lifetimes and polarization amplitudes for B0s-->J\\/psivarphi and B0d-->J\\/psiK*0 decays. Lifetimes of the heavy and light mass eigenstates in the B0s system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203±15 B0s decays we obtain tauL=(1.05+0.16-0.13±0.02) ps and tauH=(2.07+0.58-0.46±0.03)

D. Acosta; J. Adelman; T. Affolder; T. Akimoto; M. G. Albrow; D. Ambrose; S. Amerio; D. Amidei; A. Anastassov; K. Anikeev; A. Annovi; J. Antos; M. Aoki; G. Apollinari; T. Arisawa; J.-F. Arguin; A. Artikov; W. Ashmanskas; A. Attal; F. Azfar; P. Azzi-Bacchetta; N. Bacchetta; H. Bachacou; W. Badgett; A. Barbaro-Galtieri; G. J. Barker; V. E. Barnes; B. A. Barnett; S. Baroiant; M. Barone; G. Bauer; F. Bedeschi; S. Belforte; G. Bellettini; J. Bellinger; E. Ben-Haim; D. Benjamin; A. Beretvas; A. Bhatti; M. Binkley; D. Bisello; M. Bishai; R. E. Blair; C. Blocker; K. Bloom; B. Blumenfeld; A. Bocci; A. Bodek; G. Bolla; A. Bolshov; P. S. L. Booth; D. Bortoletto; J. Boudreau; S. Bourov; B. Brau; C. Bromberg; E. Brubaker; J. Budagov; H. S. Budd; K. Burkett; G. Busetto; P. Bussey; K. L. Byrum; S. Cabrera; M. Campanelli; M. Campbell; A. Canepa; M. Casarsa; D. Carlsmith; S. Carron; R. Carosi; M. Cavalli-Sforza; A. Castro; P. Catastini; D. Cauz; A. Cerri; L. Cerrito; J. Chapman; C. Chen; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; F. Chlebana; I. Cho; K. Cho; D. Chokheli; J. P. Chou; M. L. Chu; S. Chuang; J. Y. Chung; W.-H. Chung; Y. S. Chung; C. I. Ciobanu; M. A. Ciocci; A. G. Clark; D. Clark; M. Coca; A. Connolly; M. Convery; J. Conway; B. Cooper; M. Cordelli; G. Cortiana; J. Cranshaw; J. Cuevas; R. Culbertson; C. Currat; D. Cyr; D. Dagenhart; S. da Ronco; S. D'Auria; P. de Barbaro; S. de Cecco; G. de Lentdecker; S. dell'Agnello; M. dell'Orso; S. Demers; L. Demortier; M. Deninno; D. de Pedis; P. F. Derwent; C. Dionisi; J. R. Dittmann; C. Dörr; P. Doksus; A. Dominguez; S. Donati; M. Donega; J. Donini; M. D'Onofrio; T. Dorigo; V. Drollinger; K. Ebina; N. Eddy; J. Ehlers; R. Ely; R. Erbacher; M. Erdmann; D. Errede; S. Errede; R. Eusebi; H.-C. Fang; S. Farrington; I. Fedorko; W. T. Fedorko; R. G. Feild; M. Feindt; J. P. Fernandez; C. Ferretti; R. D. Field; G. Flanagan; B. Flaugher; A. Foland; S. Forrester; G. W. Foster; M. Franklin; J. C. Freeman; Y. Fujii; I. Furic; A. Gajjar; A. Gallas; J. Galyardt; M. Gallinaro; M. Garcia-Sciveres; A. F. Garfinkel; C. Gay; H. Gerberich; D. W. Gerdes; E. Gerchtein; S. Giagu; P. Giannetti; A. Gibson; K. Gibson; C. Ginsburg; K. Giolo; M. Giordani; M. Giunta; G. Giurgiu; V. Glagolev; D. Glenzinski; M. Gold; N. Goldschmidt; D. Goldstein; J. Goldstein; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González; I. Gorelov; A. T. Goshaw; Y. Gotra; K. Goulianos; A. Gresele; M. Griffiths; C. Grosso-Pilcher; U. Grundler; M. Guenther; J. Guimaraes da Costa; C. Haber; K. Hahn; S. R. Hahn; E. Halkiadakis; B.-Y. Han; R. Handler; F. Happacher; K. Hara; M. Hare; R. F. Harr; R. M. Harris; F. Hartmann; K. Hatakeyama; J. Hauser; C. Hays; H. Hayward; E. Heider; B. Heinemann; J. Heinrich; M. Hennecke; M. Herndon; C. Hill; D. Hirschbuehl; A. Hocker; K. D. Hoffman; A. Holloway; S. Hou; M. A. Houlden; B. T. Huffman; Y. Huang; R. E. Hughes; J. Huston; K. Ikado; J. Incandela; G. Introzzi; M. Iori; Y. Ishizawa; C. Issever; A. Ivanov; Y. Iwata; B. Iyutin; E. James; D. Jang; J. Jarrell; D. Jeans; H. Jensen; E. J. Jeon; M. Jones; K. K. Joo; S. Y. Jun; T. Junk; T. Kamon; J. Kang; M. Karagoz Unel; P. E. Karchin; S. Kartal; Y. Kato; Y. Kemp; R. Kephart; U. Kerzel; V. Khotilovich; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; T. H. Kim; Y. K. Kim; B. T. King; M. Kirby; L. Kirsch; S. Klimenko; B. Knuteson; B. R. Ko; H. Kobayashi; P. Koehn; D. J. Kong; K. Kondo; J. Konigsberg; K. Kordas; A. Korn; A. Korytov; K. Kotelnikov; A. V. Kotwal; A. Kovalev; J. Kraus; I. Kravchenko; A. Kreymer; J. Kroll; M. Kruse; V. Krutelyov; S. E. Kuhlmann; S. Kwang; A. T. Laasanen; S. Lai; S. Lami; S. Lammel; J. Lancaster; M. Lancaster; R. Lander; K. Lannon; A. Lath; G. Latino; R. Lauhakangas; I. Lazzizzera; Y. Le; C. Lecci; T. Lecompte; J. Lee; S. W. Lee; R. Lefèvre; N. Leonardo; S. Leone; S. Levy; J. D. Lewis; K. Li; C. Lin; M. Lindgren; T. M. Liss; A. Lister; D. O. Litvintsev; T. Liu; Y. Liu; N. S. Lockyer; A. Loginov; M. Loreti; P. Loverre; R.-S. Lu; D. Lucchesi; P. Lujan; P. Lukens; G. Lungu; L. Lyons; J. Lys; R. Lysak; D. MacQueen; R. Madrak; K. Maeshima; P. Maksimovic; L. Malferrari; G. Manca; R. Marginean; C. Marino; A. Martin; M. Martin; V. Martin; M. Martínez; T. Maruyama; H. Matsunaga; M. Mattson; P. Mazzanti; K. S. McFarland; D. McGivern; P. M. McIntyre; P. McNamara; R. Ncnulty; A. Mehta; S. Menzemer; A. Menzione; P. Merkel; C. Mesropian; A. Messina; T. Miao; N. Miladinovic; L. Miller; R. Miller; J. S. Miller; R. Miquel; S. Miscetti; G. Mitselmakher; A. Miyamoto; Y. Miyazaki; N. Moggi; B. Mohr; R. Moore; M. Morello; P. A. Movilla Fernandez; A. Mukherjee; M. Mulhearn; T. Muller; R. Mumford; A. Munar; P. Murat; J. Nachtman; S. Nahn; I. Nakamura; I. Nakano; A. Napier; R. Napora; D. Naumov; V. Necula; F. Niell; J. Nielsen; C. Nelson; T. Nelson; C. Neu; M. S. Neubauer; C. Newman-Holmes

2005-01-01

125

A capacitance servo control plunger for accurate lifetime measurement  

NASA Astrophysics Data System (ADS)

The recoil distance Doppler shift method has been widely used in the study of nuclear structure to determine the level lifetime and absolute transition probabilities. A capacitance servo control plunger based on this method has been successfully developed by the Nuclear Structure Group of the China Institute of Atomic Energy. Three microscopes were employed to check the parallelism and can therefore guarantee a delicate measurement of the distance between the target and the stopper. This new plunger made a successful performance in the test experiment and the measured lifetime of the 2+?0+ transition in 78Kr is in agreement with the previous value.

Wang, Jin-Long; Wu, Xiao-Guang; He, Chuang-Ye; Li, Guang-Sheng; Fan, Qi-Wen; Du, Ying-Hui; Wu, Yi-Heng; Hu, Shi-Peng; Zheng, Yun; Li, Cong-Bo; Li, Hong-Wei; Liu, Jia-Jian; Luo, Peng-Wei; Yao, Shun-He

2014-03-01

126

Measurement of the charged kaon lifetime with the KLOE detector  

E-print Network

We have measured the charged kaon lifetime using a sample of 15 \\times 10^6 tagged kaon decays. Charged kaons were produced in pairs at the DA\\PhiNE \\phi-factory, e^+e^- \\to \\phi \\to K^+ K^-. The decay of a K^+ was tagged by the production of a K^- and viceversa. The lifetime was obtained, for both charges, from independent measurements of the decay time and decay lenght distributions. From fits to the four distributions we find \\tau = (12.347\\pm0.030) ns.

F. Ambrosino; A. Antonelli; M. Antonelli; F. Archilli; C. Bacci; P. Beltrame; G. Bencivenni; S. Bertolucci; C. Bini; C. Bloise; S. Bocchetta; F. Bossi; P. Branchini; R. Caloi; P. Campana; G. Capon; T. Capussela; F. Ceradini; S. Chi; G. Chiefari; P. Ciambrone; E. De Lucia; A. De Santis; P. De Simone; G. De Zorzi; A. Denig; A. Di Domenico; C. Di Donato; B. Di Micco; A. Doria; M. Dreucci; G. Felici; A. Ferrari; M. L. Ferrer; S. Fiore; C. Forti; P. Franzini; C. Gatti; P. Gauzzi; S. Giovannella; E. Gorini; E. Graziani; W. Kluge; V. Kulikov; F. Lacava; G. Lanfranchi; J. Lee-Franzini; D. Leone; M. Martini; P. Massarotti; W. Mei; S. Meola; S. Miscetti; M. Moulson; S. Müller; F. Murtas; M. Napolitano; F. Nguyen; M. Palutan; E. Pasqualucci; A. Passeri; V. Patera; F. Perfetto; M. Primavera; P. Santangelo; G. Saracino; B. Sciascia; A. Sciubba; A. Sibidanov; T. Spadaro; M. Testa; L. Tortora; P. Valente; G. Venanzoni; R. Versaci; G. Xu

2008-01-11

127

Time-between-photons method for measuring fluorescence lifetimes  

NASA Astrophysics Data System (ADS)

We have applied a time-between-photons (TBP) method to measure fluorescence lifetimes in a pulsed-light excitation scheme. The TBP method has been originally proposed by Rossi and his coworkers in the field of ion photon emission microscopy (IPEM) for measuring lifetimes of ion-luminescent materials [Nucl. Instrum. Methods Phys. Res., Sect. B 267 (2009) 2193]. The TBP method has an advantage in that no reference signal is required in the instrumental setup. In the present paper, we demonstrate, for the first time to our knowledge, that the TBP method is also applicable to measure conventional fluorescence lifetimes. The TBP method suits for measuring fluorescent samples whose lifetimes are sufficiently long (?10 ns) and intensities are moderately high (?4 × 10-8 W): fluorescent samples with intermediate quantum yields for which the conventional time-correlated single-photon-counting (TC-SPC) method is somewhat difficult to employ as it is and the conventional analogue light-measurement method is still hard to use.

Mizutani, Yasuhiro; Shinagawa, Kohta; Mizuno, Takahiko; Iwata, Tetsuo

2013-01-01

128

Measurement of positron showers with a digital hadron calorimeter  

Microsoft Academic Search

A small prototype of a finely granulated digital hadron calorimeter with Resistive Plate Chambers as active elements was exposed to positrons of 1-16 GeV energy from the Fermilab test beam. The response function, energy resolution, as well as measurements of the shape of electromagnetic showers are presented. The data are compared to a Monte Carlo simulation of the set-up.

Burak Bilki; John Butler; E. May; G. Mavromanolakis; E. Norbeck; J. Repond; David Underwood; Lei Xia; Qingmin Zhang

2009-01-01

129

Phase dependence of positron annihilation in tristearin.  

NASA Technical Reports Server (NTRS)

Positron lifetime measurements have been used to investigate the polymorphism of tristearin. The results show that both positronium formation and annihilation are sensitive to the phase changes in tristearin.

Walker, W. W.; Merritt, W. G.; Cole, G. D.

1972-01-01

130

Measurement of the Polarization of Positrons Emitted in the Beta Decay of Optically Pumped SODIUM-21.  

NASA Astrophysics Data System (ADS)

The ratio of longitudinal polarizations of positrons emitted antiparallel and parallel to the nuclear spin axis of ^{21}Na was measured. The ^{21}Na nuclei were produced via the ^{20}Ne(d,n) ^{21}Na reaction in a ^{20}Ne gas target, and polarized using optical pumping with a copper-vapor laser -dye-laser system. The degree of nuclear polarization was measured by monitoring the parity-violating asymmetry in the rate of beta emission relative to the nuclear spin axis. The positron polarization was extracted from lifetime spectra of positronium formed in the presence of a strong magnetic field. The measured ratio of polarizations is consistent with the Standard-Model prediction, and with a similar measurement performed previously on ^{107 }In. Taken as a test of manifest left-right symmetric models with no mixing between the right and left -handed sectors, this measurement gives delta ^2 = -.037+/- .070, where delta = (M_{L}/M_{R})^2 is the square of the ratio of left and right-handed W boson masses.

Schewe, James Edward

131

A New Method of Neutron Detecton for UCN Lifetime Measurements  

NASA Astrophysics Data System (ADS)

A number of inconsistent neutron lifetime measurements have been reported. The disagreement among the various measurements made with material neutron traps with ultra-cold neutrons (UCN) suggests unaccounted for systematic errors in these measurements. One potential source of error is due to the long emptying times which may be time dependent due to the UCN phase space evolution in the trap. We present a way to reduce this effect.

Morris, C. L.; Salvat, D. J.; Adamek, E.; Bowman, D.; Clayton, S.; Cude, C.; Fox, W.; Hogan, G.; Hickerson, K.; Holley, A. T.; Liu, C.-Y.; Makela, M.; Manus, G.; Penttila, S.; Ramsey, J.; Saunders, A.; Sawtelle, S.; Seestrom, S. J.; Solberg, K.; Vanderwerp, J.; Vorndick, B.; Walstrom, P.; Wang, Z.; Young, A. R.

2014-03-01

132

MuLan: Towards a 1ppm muon lifetime measurement  

E-print Network

The MuLan experiment will measure the lifetime of the positive muon to 1ppm. Within the Standard Model framework, this will permit a determination of the Fermi Constant to 0.5ppm. I present an update on our progress and achievements to date.

Lynch, K R

2006-01-01

133

MuLan: Towards a 1ppm muon lifetime measurement  

E-print Network

The MuLan experiment will measure the lifetime of the positive muon to 1ppm. Within the Standard Model framework, this will permit a determination of the Fermi Constant to 0.5ppm. I present an update on our progress and achievements to date.

Kevin R. Lynch

2006-08-17

134

MuLan: Towards a 1 ppm muon lifetime measurement  

SciTech Connect

The MuLan experiment will measure the lifetime of the positive muon to 1 ppm. Within the Standard Model framework, this will permit a determination of the Fermi Constant to 0.5 ppm. I present an update on our progress and achievements to date.

Lynch, Kevin R. [Boston University Physics Department, 590 Commonwealth Ave, Boston, MA, 01824 (United States)

2006-11-17

135

MuLan: Towards a 1 ppm muon lifetime measurement  

NASA Astrophysics Data System (ADS)

The MuLan experiment will measure the lifetime of the positive muon to 1 ppm. Within the Standard Model framework, this will permit a determination of the Fermi Constant to 0.5 ppm. I present an update on our progress and achievements to date.

Lynch, Kevin R.

2006-11-01

136

A measurement of B + and B 0 lifetimes using events  

Microsoft Academic Search

A measurement of B meson lifetimes is presented using data collected from 1991 to 1993 by the DELPHI detector at the LEP collider. Samples of events with a D meson and a lepton in the same jet are selected where\\u000a

P. Abreu; W. Adam; T. Adye; E. Agasi; I. Ajinenko; R. Aleksan; G. D. Alekseev; P. P. Allport; S. Almehed; S. J. Alvsvaag; U. Amaldi; S. Amato; A. Andreazza; M. L. Andrieux; P. Antilogus; W. D. Apel; Y. Arnoud; B. Åsman; J. E. Augustin; A. Augustinus; P. Baillon; P. Bambade; F. Barao; R. Barate; G. Barbiellini; D. Y. Bardin; G. J. Barker; A. Baroncelli; O. Barring; J. A. Barrio; W. Bartl; M. J. Bates; M. Battaglia; M. Baubillier; J. Baudot; K. H. Becks; M. Begalli; P. Beilliere; Yu. Belokopytov; A. C. Benvenuti; M. Berggren; D. Bertrand; F. Bianchi; M. Bigi; M. S. Bilenky; P. Billoir; D. Bloch; M. Blume; S. Blyth; V. Bocci; T. Bolognese; M. Bonesini; W. Bonivento; P. S. L. Booth; G. Borisov; C. Bosio; S. Bosworth; O. Botner; B. Bouquet; C. Bourdarios; T. J. V. Bowcock; M. Bozzo; P. Branchini; K. D. Brand; R. A. Brenner; C. Bricman; L. Brillault; R. C. A. Brown; P. Bruckman; J. M. Brunet; L. Bugge; T. Buran; A. Buys; M. Caccia; M. Calvi; A. J. Camacho Rozas; T. Camporesi; V. Canale; M. Canepa; K. Cankocak; F. Cao; F. Carena; P. Carrilho; L. Carroll; C. Caso; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; L. Cerrito; V. Chabaud; M. Chapkin; Ph. Charpentier; L. Chaussard; J. Chauveau; P. Checchia; G. A. Chelkov; R. Chierici; P. Chliapnikov; P. Chochula; V. Chorowicz; V. Cindro; P. Collins; J. L. Contreras; R. Contri; E. Cortina; G. Cosme; F. Cossutti; H. B. Crawley; D. Crennell; G. Crosetti; J. Cuevas Maestro; S. Czellar; E. Dahl-Jensen; J. Dahm; B. Dalmagne; M. Dam; G. Damgaard; A. Daum; P. D. Dauncey; M. Davenport; W. Da Silva; C. Defoix; G. Della Ricca; P. Delpierre; N. Demaria; A. De Angelis; H. De Boeck; W. De Boer; S. De Brabandere; C. De Clercq; C. De La Vaissiere; B. De Lotto; A. De Min; L. De Paula; C. De Saint-Jean; H. Dijkstra; L. Di Ciaccio; F. Djama; J. Dolbeau; M. Donszelmann; K. Doroba; M. Dracos; J. Drees; K.-A. Drees; M. Dris; Y. Dufour; F. Dupont; D. Edsall; R. Ehret; G. Eigen; T. Ekelof; G. Ekspong; M. Elsing; J. P. Engel; N. Ershaidat; B. Erzen; E. Falk; D. Fassouliotis; M. Feindt; A. Fenyuk; A. Ferrer; T. A. Filippas; A. Firestone; P.-A. Fischer; H. Foeth; E. Fokitis; F. Fontanelli; F. Formenti; B. Franek; P. Frenkiel; D. C. Fries; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; H. Furstenau; J. Fuster; A. Galloni; D. Gamba; M. Gandelman; C. Garcia; J. Garcia; C. Gaspar; U. Gasparini; Ph. Gavillet; E. N. Gazis; D. Gele; J. P. Gerber; M. Gibbs; D. Gillespie; R. Gokieli; B. Golob; G. Gopal; L. Gorn; M. Gorski; Yu. Gouz; V. Gracco; E. Graziani; G. Grosdidier; P. Gunnarsson; M. Gunther; J. Guy; U. Haedinger; F. Hahn; M. Hahn; S. Hahn; Z. Hajduk; A. Hallgren; K. Hamacher; W. Hao; F. J. Harris; V. Hedberg; R. Henriques; J. J. Hernandez; P. Herquet; H. Herr; T. L. Hessing; E. Higon; H. J. Hilke; T. S. Hill; S. O. Holmgren; P. J. Holt; D. Holthuizen; M. Houlden; J. Hrubec; K. Huet; K. Hultqvist; P. Joannou; J. N. Jackson; R. Jacobsson; P. Jalocha; R. Janik; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; L. Jonsson; P. Jonsson; C. Joram; P. Juillot; M. Kaiser; G. Kalmus; F. Kapusta; M. Karlsson; E. Karvelas; S. Katsanevas; E. C. Katsoufis; R. Keranen; B. A. Khomenko; N. N. Khovanski; B. King; N. J. Kjaer; H. Klein; A. Klovning; P. Kluit; J. H. Koehne; B. Koene; P. Kokkinias; M. Koratzinos; V. Kostioukhine; C. Kourkoumelis; O. Kouznetsov; P.-H. Kramer; M. Krammer; C. Kreuter; J. Krolikowski; I. Kronkvist; Z. Krumstein; W. Krupinski; P. Kubinec; W. Kucewicz; K. Kurvinen; C. Lacasta; I. Laktineh; S. Lamblot; J. W. Lamsa; L. Lanceri; P. Langefeld; I. Last; J. P. Laugier; R. Lauhakangas; G. Leder; F. Ledroit; V. Lefebure; C. K. Legan; R. Leitner; Y. Lemoigne; J. Lemonne; G. Lenzen; V. Lepeltier; T. Lesiak; D. Liko; R. Lindner; A. Lipniacka; I. Lippi; B. Loerstad; M. Lokajicek; J. G. Loken; J. M. Lopez; A. Lopez-Fernandez; M. A. Lopez Aguera; D. Loukas; P. Lutz; L. Lyons; J. MacNaughton; G. Maehlum; A. Maio; V. Malychev; F. Mandl; J. Marco; B. Marechal; M. Margoni; J. C. Marin; C. Mariotti; A. Markou; T. Maron; C. Martinez-Rivero; F. Martinez-Vidal; S. Marti i Garcia; F. Matorras; C. Matteuzzi; G. Matthiae; M. Mazzucato; R. Mc Cubbin; R. Mc Kay; R. Mc Nulty; J. Medbo; C. Meroni; W. T. Meyer; M. Michelotto; E. Migliore; L. Mirabito; W. A. Mitaroff; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; L. M. Mundim; W. J. Murray; B. Muryn; G. Myatt; F. Naraghi; F. L. Navarria; S. Navas; P. Negri; S. Nemecek; W. Neumann; R. Nicolaidou; B. S. Nielsen; M. Nieuwenhuizen; V. Nikolaenko; P. Niss; A. Nomerotski; A. Normand; W. Oberschulte-Beckmann; V. Obraztsov; A. G. Olshevski; A. Onofre; R. Orava; K. Osterberg; A. Ouraou; P. Paganini; M. Paganoni; P. Pages; H. Palka; Th. D. Papadopoulou; L. Pape; C. Parkes; F. Parodi; A. Passeri; M. Pegoraro; L. Peralta; H. Pernegger; M. Pernicka; A. Perrotta; C. Petridou; A. Petrolini

1995-01-01

137

Improved measurement of the B 0 and B + meson lifetimes  

Microsoft Academic Search

The lifetimes of the B 0 and B + mesons have been measured with the Aleph detector at LEP, using approximately 3 million hadronic Z decays collected in the period 1991 1994. In the first of three methods, semileptonic decays of B 0 and B + mesons were partially reconstructed by identifying events containing a lepton with an associated D*-

D. Buskulic; I. de Bonis; D. Decamp; P. Ghez; C. Goy; J. P. Lees; A. Lucotte; M. N. Minard; P. Odier; B. Pietrzyk; M. P. Casado; M. Chmeissani; J. M. Crespo; M. Delfino; I. Efthymiopoulos; E. Fernandez; M. Fernandez-Bosman; L. Garrido; A. Juste; M. Martinez; S. Orteu; A. Pacheco; C. Padilla; A. Pascual; J. A. Perlas; I. Riu; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; G. Gelao; M. Girone; G. Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Nuzzo; A. Ranieri; G. Raso; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; R. Alemany; A. O. Bazarko; G. Bonvicini; M. Cattaneo; P. Comas; P. Coyle; H. Drevermann; R. W. Forty; M. Frank; R. Hagelberg; J. Harvey; P. Janot; B. Jost; E. Kneringer; J. Knobloch; I. Lehraus; E. B. Martin; P. Mato; A. Minten; R. Miquel; Ll. M. Mir; L. Moneta; T. Oest; F. Palla; J. R. Pater; J. F. Pusztaszeri; F. Ranjard; P. Rensing; L. Rolandi; D. Schlatter; M. Schmelling; O. Schneider; W. Tejessy; I. R. Tomalin; A. Venturi; H. Wachsmuth; A. Wagner; T. Wildish; Z. Ajaltouni; A. Barrès; C. Boyer; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J.-C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; J. M. Rossignol; T. Fearnley; J. B. Hansen; J. D. Hansen; P. H. Hansen; B. S. Nilsson; A. Wäänänen; A. Kyriakis; C. Markou; E. Simopoulou; I. Siotis; A. Vayaki; K. Zachariadou; A. Blondel; G. Bonneaud; J. C. Brient; P. Bourdon; A. Rougé; M. Rumpf; A. Valassi; M. Verderi; H. Videau; D. J. Candlin; M. I. Parsons; E. Focardi; G. Parrini; M. Corden; C. Georgiopoulos; D. E. Jaffe; A. Antonelli; G. Bencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; D. Casper; V. Chiarella; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; L. Passalacqua; M. Pepe-Altarelli; L. Curtis; S. J. Dorris; A. W. Halley; I. G. Knowles; J. G. Lynch; V. O'Shea; C. Raine; P. Reeves; J. M. Scarr; K. Smith; A. S. Thompson; F. Thomson; S. Thorn; R. M. Turnbull; U. Becker; C. Geweniger; G. Graefe; P. Hanke; G. Hansper; V. Hepp; E. E. Kluge; A. Putzer; B. Rensch; M. Schmidt; J. Sommer; H. Stenzel; K. Tittel; S. Werner; M. Wunsch; D. Abbaneo; R. Beuselinck; D. M. Binnie; W. Cameron; P. J. Dornan; A. Moutoussi; J. Nash; J. K. Sedgbeer; A. M. Stacey; M. D. Williams; G. Dissertori; P. Girtler; D. Kuhn; G. Rudolph; A. P. Betteridge; C. K. Bowdery; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; T. Sloan; M. I. Williams; A. Galla; A. M. Greene; K. Kleinknecht; G. Quast; B. Renk; E. Rohne; H. G. Sander; P. van Gemmeren; C. Zeitnitz; J. J. Aubert; A. M. Bencheikh; C. Benchouk; A. Bonissent; G. Bujosa; D. Calvet; J. Carr; C. Diaconu; F. Etienne; N. Konstantinidis; P. Payre; D. Rousseau; M. Talby; A. Sadouki; M. Thulasidas; K. Trabelsi; M. Aleppo; F. Ragusa; I. Abt; R. Assmann; C. Bauer; W. Blum; H. Dietl; F. Dydak; G. Ganis; C. Gotzhein; K. Jakobs; H. Kroha; G. Lütjens; G. Lutz; W. Männer; H. G. Moser; R. Richter; A. Rosado-Schlosser; S. Schael; R. Settles; H. Seywerd; R. St. Denis; W. Wiedenmann; G. Wolf; J. Boucrot; O. Callot; A. Cordier; M. Davier; L. Duflot; J. F. Grivaz; Ph. Heusse; M. Jacquet; D. W. Kim; F. Le Diberder; J. Lefrançois; A. M. Lutz; I. Nikolic; H. J. Park; I. C. Park; M. H. Schune; S. Simion; J. J. Veillet; I. Videau; P. Azzurri; G. Bagliesi; G. Batignani; S. Bettarini; C. Bozzi; G. Calderini; M. Carpinelli; M. A. Ciocci; V. Ciulli; R. Dell'Orso; R. Fantechi; I. Ferrante; L. Foà; F. Forti; A. Giassi; M. A. Giorgi; A. Gregorio; F. Ligabue; A. Lusiani; P. S. Marrocchesi; A. Messineo; G. Rizzo; G. Sanguinetti; A. Sciabà; P. Spagnolo; J. Steinberger; R. Tenchini; G. Tonelli; C. Vannini; P. G. Verdini; J. Walsh; G. A. Blair; L. M. Bryant; F. Cerutti; J. T. Chambers; Y. S. Gao; M. G. Green; T. Medcalf; P. Perrodo; J. A. Strong; J. H. von Wimmersperg-Toeller; D. R. Botterill; R. W. Clifft; T. R. Edgecock; S. Haywood; P. Maley; P. R. Norton; J. C. Thompson; A. E. Wright; B. Bloch-Devaux; P. Colas; S. Emery; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; B. Marx; P. Perez; J. Rander; J. F. Renardy; A. Roussarie; J. P. Schuller; J. Schwindling; A. Trabelsi; B. Vallage; S. N. Black; J. H. Dann; R. P. Johnson; H. Y. Kim; A. M. Litke; M. A. McNeil; G. Taylor; C. N. Booth; R. Boswell; C. A. J. Brew; S. Cartwright; F. Combley; A. Koksal; M. Letho; W. M. Newton; J. Reeve; L. F. Thompson; A. Böhrer; S. Brandt; V. Büscher; G. Cowan; C. Grupen; G. Lutters; J. Minguet-Rodriguez; F. Rivera; P. Saraiva; L. Smolik; F. Stephan; M. Apollonio; L. Bosisio; R. Della Marina; G. Giannini; B. Gobbo; G. Musolino; J. Rothberg; S. Wasserbaech; S. R. Armstrong; L. Bellantoni; P. Elmer; Z. Feng; D. P. S. Ferguson; S. González; J. Grahl; T. C. Greening; J. L. Harton; O. J. Hayes; H. Hu; P. A. McNamara; J. M. Nachtman; W. Orejudos

1996-01-01

138

Precision Measurement of the ?[0 over b] Baryon Lifetime  

E-print Network

The ratio of the ?[0 over b] baryon lifetime to that of the B?[superscript 0] meson is measured using 1.0??fb[superscript -1] of integrated luminosity in 7 TeV center-of-mass energy pp collisions at the LHC. The ?[0 over ...

Williams, Michael

139

Lifetime measurements of the 7d levels of atomic francium  

Microsoft Academic Search

Summary form only given. Atomic lifetime measurements are important probes of atomic structure because they depend on the initial and final state wave functions and the interaction that connects them. The study of francium, the heaviest alkali, has two advantages over other heavy elements. It has a simple atomic structure to calculate accurately, and it is possible to trap it

J. S. Grossman; C. T. Langlois; M. R. Pearson; L. A. Orozco; G. D. Sprouse

2000-01-01

140

Measuring Luminescence Lifetime With Help of a DSP  

NASA Technical Reports Server (NTRS)

An instrument for measuring the lifetime of luminescence (fluorescence or phosphorescence) includes a digital signal processor (DSP) as the primary means of control, generation of excitation signals, and analysis of response signals. The DSP hardware in the present instrument makes it possible to switch among a variety of operating modes by making changes in software only.

Danielson, J. D. S.

2009-01-01

141

Lifetime Measurement of the 8s Level in Francium  

E-print Network

We measure the lifetime of the 8s level on a magneto-optically trapped sample of ^{210}Fr atoms with time-correlated single-photon counting. The 7P_{1/2} state serves as the resonant intermediate level for two-photon excitation of the 8s level completed with a 1300 nm laser. Analysis of the fluorescence decay through the the 7P_{3/2} level gives 53.30 +- 0.44 ns for the 8s level lifetime.

Gómez, E; Galvan, A P; Sprouse, G D

2004-01-01

142

Lifetime measurement of the 8s level in francium  

SciTech Connect

We measure the lifetime of the 8s level of {sup 210}Fr atoms on a magneto-optically trapped sample with time-correlated single-photon counting. The 7P{sub 1/2} state serves as the resonant intermediate level for two-step excitation of the 8s level completed with a 1.3-{mu}m laser. Analysis of the fluorescence decay through the 7P{sub 3/2} level gives 53.30{+-}0.44 ns for the 8s level lifetime.

Gomez, E.; Sprouse, G.D. [Department of Physics and Astronomy, SUNY Stony Brook, Stony Brook, New York 11794-3800 (United States); Orozco, L.A.; Galvan, A. Perez [Department of Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)

2005-06-15

143

Measurement of the B+ and B0 meson lifetimes  

Microsoft Academic Search

The lifetimes of the B+ and B0 mesons have been measured using fully reconstructed decays. In a sample of ~49 600J\\/psi-->mu+mu- decays recorded with the Collider Detector at Fermilab, 148+\\/-16 B+ and 121+\\/-16B0 mesons have been reconstructed using the silicon vertex detector. Unbinned likelihood fits to the proper lifetime distributions of these B mesons give tau+=1.61+\\/-0.16 (stat)+\\/-0.05 (syst) ps, tau0=1.57+\\/-0.18

F. Abe; M. Albrow; D. Amidei; C. Anway-Wiese; G. Apollinari; H. Areti; P. Auchincloss; F. Azfar; P. Azzi; N. Bacchetta; W. Badgett; M. W. Bailey; J. Bao; P. de Barbaro; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Bartalini; G. Bauer; T. Baumann; F. Bedeschi; S. Behrends; S. Belforte; G. Bellettini; J. Bellinger; D. Benjamin; J. Benlloch; D. Benton; A. Beretvas; J. P. Berge; S. Bertolucci; A. Bhatti; K. Biery; M. Binkley; F. Bird; D. Bisello; R. E. Blair; C. Blocker; A. Bodek; V. Bolognesi; D. Bortoletto; C. Boswell; T. Boulos; G. Brandenburg; E. Buckley-Geer; H. S. Budd; K. Burkett; G. Busetto; A. Byon-Wagner; K. L. Byrum; C. Campagnari; M. Campbell; A. Caner; W. Carithers; D. Carlsmith; A. Castro; Y. Cen; F. Cervelli; J. Chapman; G. Chiarelli; T. Chikamatsu; S. Cihangir; A. G. Clark; M. Cobal; M. Contreras; J. Cooper; M. Cordelli; D. P. Coupal; D. Crane; J. D. Cunningham; T. Daniels; F. Dejongh; S. dell'agnello; M. dell'orso; L. Demortier; B. Denby; M. Deninno; P. F. Derwent; T. Devlin; M. Dickson; S. Donati; J. P. Done; R. B. Drucker; A. Dunn; K. Einsweiler; J. E. Elias; R. Ely; E. Engels; S. Eno; D. Errede; S. Errede; A. Etchegoyen; Q. Fan; B. Farhat; I. Fiori; B. Flaugher; G. W. Foster; M. Franklin; M. Frautschi; J. Freeman; J. Friedman; H. Frisch; A. Fry; T. A. Fuess; Y. Fukui; S. Funaki; G. Gagliardi; M. Gallinaro; A. F. Garfinkel; S. Geer; D. W. Gerdes; P. Giannetti; N. Giokaris; P. Giromini; L. Gladney; D. Glenzinski; M. Gold; J. Gonzalez; A. Gordon; A. T. Goshaw; K. Goulianos; H. Grassmann; A. Grewal; G. Grieco; L. Groer; C. Grosso-Pilcher; C. Haber; S. R. Hahn; R. Handler; R. M. Hans; K. Hara; B. Harral; R. M. Harris; S. A. Hauger; J. Hauser; C. Hawk; J. Heinrich; D. Hennessy; R. Hollebeek; L. Holloway; A. Hölscher; S. Hong; G. Houk; P. Hu; B. T. Huffman; R. Hughes; P. Hurst; J. Huston; J. Huth; J. Hylen; M. Incagli; J. Incandela; H. Iso; H. Jensen; C. P. Jessop; U. Joshi; R. W. Kadel; E. Kajfasz; T. Kamon; T. Kaneko; D. A. Kardelis; H. Kasha; Y. Kato; L. Keeble; R. D. Kennedy; R. Kephart; P. Kesten; D. Kestenbaum; R. M. Keup; H. Keutelian; F. Keyvan; D. H. Kim; H. S. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; L. Kirsch; P. Koehn; K. Kondo; J. Konigsberg; S. Kopp; K. Kordas; W. Koska; E. Kovacs; M. Krasberg; J. Kroll; M. Kruse; S. E. Kuhlmann; E. Kuns; A. T. Laasanen; S. Lammel; J. I. Lamoureux; T. Lecompte; S. Leone; J. D. Lewis; P. Limon; M. Lindgren; T. M. Liss; N. Lockyer; O. Long; M. Loreti; E. H. Low; D. Lucchesi; C. B. Luchini; P. Lukens; P. Maas; K. Maeshima; A. Maghakian; M. Mangano; J. Mansour; M. Mariotti; J. P. Marriner; A. Martin; J. A. Matthews; R. Mattingly; P. McIntyre; P. Melese; A. Menzione; E. Meschi; G. Michail; S. Mikamo; M. Miller; T. Mimashi; S. Miscetti; M. Mishina; H. Mitsushio; S. Miyashita; Y. Morita; S. Moulding; J. Mueller; A. Mukherjee; T. Muller; P. Musgrave; L. F. Nakae; I. Nakano; C. Nelson; D. Neuberger; C. Newman-Holmes; L. Nodulman; S. Ogawa; K. E. Ohl; R. Oishi; T. Okusawa; C. Pagliarone; R. Paoletti; V. Papadimitriou; J. Patrick; G. Pauletta; L. Pescara; M. D. Peters; T. J. Phillips; G. Piacentino; M. Pillai; R. Plunkett; L. Pondrom; N. Produit; J. Proudfoot; F. Ptohos; G. Punzi; K. Ragan; F. Rimondi; L. Ristori; M. Roach-Bellino; W. J. Robertson; T. Rodrigo; J. Romano; L. Rosenson; W. K. Sakumoto; D. Saltzberg; A. Sansoni; V. Scarpine; A. Schindler; P. Schlabach; E. E. Schmidt; M. P. Schmidt; O. Schneider; G. F. Sciacca; A. Scribano; S. Segler; S. Seidel; Y. Seiya; G. Sganos; M. Shapiro; N. M. Shaw; Q. Shen; P. F. Shepard; M. Shimojima; M. Shochet; J. Siegrist; A. Sill; P. Sinervo; P. Singh; J. Skarha; K. Sliwa; D. A. Smith; F. D. Snider; L. Song; T. Song; J. Spalding; P. Sphicas; A. Spies; L. Stanco; J. Steele; A. Stefanini; K. Strahl; J. Strait; G. Sullivan; K. Sumorok; R. L. Swartz; T. Takahashi; K. Takikawa; F. Tartarelli; Y. Teramoto; S. Tether; D. Theriot; J. Thomas; R. Thun; M. Timko; P. Tipton; A. Titov; S. Tkaczyk; A. Tollestrup; J. Tonnison; J. F. de Troconiz; J. Tseng; M. Turcotte; N. Turini; N. Uemura; F. Ukegawa; G. Unal; S. Vejcik; R. Vidal; M. Vondracek; R. G. Wagner; R. L. Wagner; N. Wainer; R. C. Walker; J. Wang; Q. F. Wang; A. Warburton; G. Watts; T. Watts; R. Webb; C. Wendt; H. Wenzel; W. C. Wester; T. Westhusing; A. B. Wicklund; E. Wicklund; R. Wilkinson; H. H. Williams; P. Wilson; B. L. Winer; J. Wolinski; D. Y. Wu; X. Wu; J. Wyss; A. Yagil; W. Yao; K. Yasuoka; Y. Ye; G. P. Yeh; M. Yin; J. Yoh; T. Yoshida; D. Yovanovitch; I. Yu; J. C. Yun; A. Zanetti; F. Zetti; S. Zhang; W. Zhang; S. Zucchelli

1994-01-01

144

Recent positron-atom cross section measurements and calculations  

NASA Astrophysics Data System (ADS)

We review recent cross section results for low-energy positron scattering from atomic targets. A comparison of the latest measurements and calculations for positron collisions with the noble gases and a brief update of the newest studies on other atoms is presented. In particular, we provide an overview of the cross sections for elastic scattering, positronium formation, direct and total ionisation, as well as total scattering, at energies typically between about 0.1 and a few hundred eV. We discuss the differences in the current experimental data sets and compare those results to the available theoretical models. Recommended data sets for the total cross section are also reported for each noble gas. A summary of the recent developments in the scattering from other atoms, such as atomic hydrogen, the alkali and alkaline-earth metals, and two-electron systems is finally provided.

Chiari, Luca; Zecca, Antonio

2014-10-01

145

Tracking of the micro-structural changes of levonorgestrel-releasing intrauterine system by positron annihilation lifetime spectroscopy.  

PubMed

The morphology and the micro-structural changes of levonorgestrel-releasing intrauterine systems (IUSs) were studied in relation to the duration of their application. The morphology of the removed IUSs was examined without pre-treatment by scanning electron microscopy. The micro-structural changes of the different layers of IUSs were tracked by positron annihilation lifetime spectroscopy. Besides the previously found incrustation formation, the free volume of the hormone containing reservoir was remarkably increased after 3 years of application, thus increasing the real volume of the core of the systems. Although the free volume of the membrane encasing the core was not significantly changed in the course of the application, as a result of the core expansion, microcracks could be formed on the membrane surface. Along these cracks, deposits of different compositions can be formed, causing inflammatory complications and influencing the drug release of IUSs. Stability tests in combination with micro-structural screening of such IUSs could be required during their development phase to avoid the undesired side effects. PMID:20638215

Patai, Kálmán; Szente, Virág; Süvegh, Károly; Zelkó, Romána

2010-12-01

146

Bs mixing and lifetime difference measurements at CDF  

E-print Network

We review latest experimental results on the Bs mixing and lifetime difference measurements at CDF. We report on the latest beta_s and dGamma_s results from Bs->J/psi phi. We also discuss flavor specific dGamma_s measurements, including information from hadronic channels, Bs->DsDs and Bs->KK. We describe the new flavor tagging methodology and its calibration using the Bs oscillations.

Pierluigi Catastini; for the CDF Collaboration

2009-10-13

147

Lifetime and Branching Fraction Measurements for P II  

Microsoft Academic Search

Lifetime and branching fraction measurements using foil excitation of a fast ion beam are reported for transitions within the 3s^2 3p^2 -- 3s^2 3p4s multiplet in P II. The studies were undertaken to test theoretical and semiempirical calculations which suggest that branching fractions within this multiplet can be accurately specified from intermediate coupling amplitudes deduced from measured energy level data.

Stephanie Torok; Mike Brown; Richard Irving; Steven Federman; Lorenzo Curtis

2006-01-01

148

Detailed report of the MuLan measurement of the positive muon lifetime and determination of the Fermi constant  

NASA Astrophysics Data System (ADS)

We present a detailed report of the method, setup, analysis, and results of a precision measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured, nearly 100% polarized surface muon beam and a segmented, fast-timing plastic scintillator array. The measurement employed two target arrangements: a magnetized ferromagnetic target with a ˜4kG internal magnetic field and a crystal quartz target in a 130 G external magnetic field. Approximately 1.6×1012 positrons were accumulated and together the data yield a muon lifetime of ??(MuLan)=2196980.3(2.2)ps (1.0 ppm), 30 times more precise than previous generations of lifetime experiments. The lifetime measurement yields the most accurate value of the Fermi constant GF(MuLan)=1.1663787(6)×10-5GeV-2 (0.5 ppm). It also enables new precision studies of weak interactions via lifetime measurements of muonic atoms.

Tishchenko, V.; Battu, S.; Carey, R. M.; Chitwood, D. B.; Crnkovic, J.; Debevec, P. T.; Dhamija, S.; Earle, W.; Gafarov, A.; Giovanetti, K.; Gorringe, T. P.; Gray, F. E.; Hartwig, Z.; Hertzog, D. W.; Johnson, B.; Kammel, P.; Kiburg, B.; Kizilgul, S.; Kunkle, J.; Lauss, B.; Logashenko, I.; Lynch, K. R.; McNabb, R.; Miller, J. P.; Mulhauser, F.; Onderwater, C. J. G.; Peng, Q.; Phillips, J.; Rath, S.; Roberts, B. L.; Webber, D. M.; Winter, P.; Wolfe, B.

2013-03-01

149

Detailed Report of the MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant  

E-print Network

We present a detailed report of the method, setup, analysis and results of a precision measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured, nearly 100%-polarized, surface muon beam and a segmented, fast-timing, plastic scintillator array. The measurement employed two target arrangements; a magnetized ferromagnetic target with a ~4 kG internal magnetic field and a crystal quartz target in a 130 G external magnetic field. Approximately 1.6 x 10^{12} positrons were accumulated and together the data yield a muon lifetime of tau_{mu}(MuLan) = 2196980.3(2.2) ps (1.0 ppm), thirty times more precise than previous generations of lifetime experiments. The lifetime measurement yields the most accurate value of the Fermi constant G_F (MuLan) = 1.1663787(6) x 10^{-5} GeV^{-2} (0.5 ppm). It also enables new precision studies of weak interactions via lifetime measurements of muonic atoms.

Tishchenko, V; Carey, R M; Chitwood, D B; Crnkovic, J; Debevec, P T; Dhamija, S; Earle, W; Gafarov, A; Giovanetti, K; Gorringe, T P; Gray, F E; Hartwig, Z; Hertzog, D W; Johnson, B; Kammel, P; Kiburg, B; Kizilgul, S; Kunkle, J; Lauss, B; Logashenko, I; Lynch, K R; McNabb, R; Miller, J P; Mulhauser, F; Onderwater, C J G; Peng, Q; Phillips, J; Rath, S; Roberts, B L; Webber, D M; Winter, P; Wolfe, B

2012-01-01

150

Detailed Report of the MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant  

E-print Network

We present a detailed report of the method, setup, analysis and results of a precision measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured, nearly 100%-polarized, surface muon beam and a segmented, fast-timing, plastic scintillator array. The measurement employed two target arrangements; a magnetized ferromagnetic target with a ~4 kG internal magnetic field and a crystal quartz target in a 130 G external magnetic field. Approximately 1.6 x 10^{12} positrons were accumulated and together the data yield a muon lifetime of tau_{mu}(MuLan) = 2196980.3(2.2) ps (1.0 ppm), thirty times more precise than previous generations of lifetime experiments. The lifetime measurement yields the most accurate value of the Fermi constant G_F (MuLan) = 1.1663787(6) x 10^{-5} GeV^{-2} (0.5 ppm). It also enables new precision studies of weak interactions via lifetime measurements of muonic atoms.

V. Tishchenko; S. Battu; R. M. Carey; D. B. Chitwood; J. Crnkovic; P. T. Debevec; S. Dhamija; W. Earle; A. Gafarov; K. Giovanetti; T. P. Gorringe; F. E. Gray; Z. Hartwig; D. W. Hertzog; B. Johnson; P. Kammel; B. Kiburg; S. Kizilgul; J. Kunkle; B. Lauss; I. Logashenko; K. R. Lynch; R. McNabb; J. P. Miller; F. Mulhauser; C. J. G. Onderwater; Q. Peng; J. Phillips; S. Rath; B. L. Roberts; D. M. Webber; P. Winter; B. Wolfe

2012-11-05

151

A Measurement of the Bs Lifetime at CDF Run II  

SciTech Connect

This thesis describes a measurement of the proper lifetime of the B{sub s}{sup 0} mesons produced in proton-antiproton collisions at a center of mass energy of 1.96 TeV, collected by the CDF experiment at Fermilab. The B{sub s}{sup 0} meson lifetime is measured in its semileptonic decay mode, B{sub s}{sup 0} {yields} {ell}{sup +}{nu}{sub {ell}}D{sub s}{sup -}. The D{sub s}{sup -} meson candidates are reconstructed in the decay mode D{sub s}{sup -} {yields} {phi}{pi}, with {phi} {yields} K{sup +}K{sup -}, in a trigger sample which requires a muon or an electron and another track which has a large impact parameters. The large impact parameter track is required by the silicon vertex trigger which is an innovative triggering device which has not previously been used in lifetime measurements. A total of 905 {+-} B{sub s}{sup 0} candidates are reconstructed in a sample which has an integrated luminosity of 140 pb{sup -1} using data gathered between February 2002 and August 2003. The pseudo-proper lifetime distribution of these candidates is fitted with an unbinned maximum likelihood fit. This fit takes into account the missing momentum carried by the neutrino and the bias caused by requiring a track with large impact parameter by modeling these effects in simulations. The fit yields the result for the B{sub s}{sup 0} proper lifetime: c{tau}(B{sub s}{sup 0}) = 419 {+-} 28{sub -13}{sup +16} {micro}m and {tau}(B{sub s}{sup 0}) = 1.397 {+-} 0.093{sub -0.043}{sup +0.053} ps where the first error is statistical and the second is systematic.

Farrington, Sinead

2004-01-01

152

Measurement of the Lambdab0 lifetime using semileptonic decays.  

PubMed

We report a measurement of the Lambda(b)(0) lifetime using a sample corresponding to 1.3 fb(-1) of data collected by the D0 experiment in 2002-2006 during run II of the Fermilab Tevatron collider. The Lambda(b)(0) baryon is reconstructed via the decay Lambda(b)(0)-->micronuLambda(c)(+)X. Using 4437+/-329 signal candidates, we measure the Lambda(b)(0) lifetime to be tau(Lambda(b)(0))=1.290(-0.110)(+0.119)(stat)(-0.091)(+0.087)(syst) ps, which is among the most precise measurements in semileptonic Lambda(b)(0) decays. This result is in good agreement with the world average value. PMID:17995396

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Banerjee, P; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chan, K; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clément, C; Clément, B; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; de Jong, P; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, J; Guo, F; Gutierrez, P; Gutierrez, G; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J R; Kalk, J M; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kothari, B; Kozelov, A V; Krop, D; Kryemadhi, A; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lazoflores, J; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lellouch, J; Lesne, V; Leveque, J; Lewin, M; Lewis, P; Li, J; Li, Q Z; Li, L; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, J; Meyer, A; Michaut, M; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perea, P M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y

2007-11-01

153

Measurement of excitation functions and radiative lifetimes of oxygen ions  

NASA Astrophysics Data System (ADS)

Oxygen ions from a 2 MV tandem accelerator have been used in beam-foil spectroscopic studies of O II, O III and O IV in the wavelength region 2000 5000 Å. Excitation functions for relative level populations in O II, O III and O IV in the incident energy range of 1.2 3.75 MeV have been measured and interpreted in terms of the independent electron model. Mean radiative lifetime measurements for a number of levels including cascades 4631 Å feeding to 2450 Å and 4344 Å feeding to 2385 Å in O IV have resulted in consistent values. Lifetime measurements for some of the O II levels of astrophysical interest have been reinvestigated and significant deviations from earlier values were observed.

Mythili, R.; Singh, P.; Bhattacharya, P. K.; Parui, A. B.; Betigeri, M. G.; Raja Rao, P. M.; Krishnamurthy, G.; Raju, V. S.

1988-12-01

154

A Measurement of the D+(s) lifetime  

SciTech Connect

A high statistics measurement of the D{sub s}{sup +} lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. They describe the analysis of the two decay modes, D{sub s}{sup +} {yields} {phi}(1020){pi}{sup +} and D{sub s}{sup +} {yields} {bar K}*(892){sup 0}K{sup +}, used for the measurement. The measured lifetime is 507.4 {+-} 5.5(stat.) {+-} 5.1(syst.) is using 8961 {+-} 105 D{sub s}{sup +} {yields} {phi}(1020){pi}{sup +} and 4680 {+-} 90 D{sub s}{sup +} {yields} {bar K}*(892){sup 0} K{sup +} decays. This is a significant improvement over the present world average.

Link, J.M.; Yager, P.M.; /UC, Davis; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferi, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; dos; /Rio de Janeiro, CBPF; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; /CINVESTAV, IPN; Agostino, L.; Cinquini, L.; Cumalat, J.P. /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U. /North Carolina U. /Pavia U. /INFN, Pavia /Rio

2005-04-01

155

Measuring the muon lifetime with the MuLan experiment at PSI  

NASA Astrophysics Data System (ADS)

The Muon Lifetime Analysis (MuLan) Collaboration's goal is to produce a measurement of the positive muon lifetime with a precision of 1 ppm. This measurement, along with recent developments in theory, will lead to a twenty-fold improvement in the determination of the Fermi coupling constant, G_F. A novel kicking system is being developed to create a pulsed beam of surface muons in the ?E3 area at the Paul Scherrer Institut. The kicker will allow approximately 20 muons to be stopped in a thin depolarizing target during a 5 ?s accumulation phase. This is followed by a 22 ?s measuring phase where the decay positrons are detected by a segmented scintillator detector. The detector forms a truncated icosahedron surrounding the target region, and is composed of 340 independent scintillators forming 170 individual coincident tiles. Each scintillator is to be readout by separate 500 MHz waveform digitizers, allowing the precise determination of decay times. Much of the system has been tested during a Fall 2003 commissioning run. We will discuss the status of the experiment and the preliminary results from the analysis of the data to date.

Chitwood, Daniel

2004-05-01

156

Measurements of the Bs0 and Lambdab0 lifetimes  

Microsoft Academic Search

This paper presents updated measurements of the lifetimes of the Bs0 meson and the Lambdab0 baryon using 4.4 million hadronic Z0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of Bs0 decays is obtained using Ds-l+ combinations, where the Ds- is fully reconstructed in the phipi-, K*0K- and K-K0S decay channels and partially reconstructed

K. Ackerstaff; G. Alexander; J. Allison; N. Altekamp; K. J. Anderson; S. Anderson; S. Arcelli; S. Asai; S. F. Ashby; D. Axen; G. Azuelos; A. H. Ball; E. Barberio; R. J. Barlow; R. Bartoldus; J. R. Batley; S. Baumann; J. Bechtluft; C. Beeston; T. Behnke; A. N. Bell; K. W. Bell; G. Bella; S. Bentvelsen; S. Bethke; S. Betts; O. Biebel; A. Biguzzi; S. D. Bird; V. Blobel; I. J. Bloodworth; J. E. Bloomer; M. Bobinski; P. Bock; D. Bonacorsi; M. Boutemeur; S. Braibant; L. Brigliadori; R. M. Brown; H. J. Burckhart; C. Burgard; R. Bürgin; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; D. G. Charlton; D. Chrisman; P. E. L. Clarke; I. Cohen; J. E. Conboy; O. C. Cooke; C. Couyoumtzelis; R. L. Coxe; M. Cuffiani; S. Dado; C. Dallapiccola; G. M. Dallavalle; R. Davis; S. de Jong; L. A. del Pozo; K. Desch; B. Dienes; M. S. Dixit; M. Doucet; E. Duchovni; G. Duckeck; I. P. Duerdoth; D. Eatough; J. E. G. Edwards; P. G. Estabrooks; H. G. Evans; M. Evans; F. Fabbri; A. Fanfani; M. Fanti; A. A. Faust; L. Feld; F. Fiedler; M. Fierro; H. M. Fischer; I. Fleck; R. Folman; D. G. Fong; M. Foucher; A. Fürtjes; D. I. Futyan; P. Gagnon; J. W. Gary; J. Gascon; S. M. Gascon-Shotkin; N. I. Geddes; C. Geich-Gimbel; T. Geralis; G. Giacomelli; P. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; D. M. Gingrich; D. Glenzinski; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; E. Gross; J. Grunhaus; M. Gruwé; C. Hajdu; G. G. Hanson; M. Hansroul; M. Hapke; C. K. Hargrove; P. A. Hart; C. Hartmann; M. Hauschild; C. M. Hawkes; R. Hawkings; R. J. Hemingway; M. Herndon; G. Herten; R. D. Heuer; M. D. Hildreth; J. C. Hill; S. J. Hillier; P. R. Hobson; A. Hocker; R. J. Homer; A. K. Honma; D. Horváth; K. R. Hossain; R. Howard; P. Hüntemeyer; D. E. Hutchcroft; P. Igo-Kemenes; D. C. Imrie; M. R. Ingram; K. Ishii; A. Jawahery; P. W. Jeffreys; H. Jeremie; M. Jimack; A. Joly; C. R. Jones; G. Jones; M. Jones; U. Jost; P. Jovanovic; T. R. Junk; J. Kanzaki; D. Karlen; V. Kartvelishvili; K. Kawagoe; T. Kawamoto; P. I. Kayal; R. K. Keeler; R. G. Kellogg; B. W. Kennedy; J. Kirk; A. Klier; S. Kluth; T. Kobayashi; M. Kobel; D. S. Koetke; T. P. Kokott; M. Kolrep; S. Komamiya; T. Kress; P. Krieger; J. von Krogh; P. Kyberd; G. D. Lafferty; R. Lahmann; W. P. Lai; D. Lanske; J. Lauber; S. R. Lautenschlager; J. G. Layter; D. Lazic; A. M. Lee; E. Lefebvre; D. Lellouch; J. Letts; L. Levinson; S. L. Lloyd; F. K. Loebinger; G. D. Long; M. J. Losty; J. Ludwig; D. Lui; A. Macchiolo; A. MacPherson; M. Mannelli; S. Marcellini; C. Markopoulos; C. Markus; A. J. Martin; J. P. Martin; G. Martinez; T. Mashimo; P. Mättig; W. J. McDonald; J. McKenna; E. A. McKigney; T. J. McMahon; R. A. McPherson; F. Meijers; S. Menke; F. S. Merritt; H. Mes; J. Meyer; A. Michelini; G. Mikenberg; D. J. Miller; A. Mincer; R. Mir; W. Mohr; A. Montanari; T. Mori; U. Müller; S. Mihara; K. Nagai; I. Nakamura; H. A. Neal; B. Nellen; R. Nisius; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; A. Oh; N. J. Oldershaw; M. J. Oreglia; S. Orito; J. Pálinkás; G. Pásztor; J. R. Pater; G. N. Patrick; J. Patt; R. Perez-Ochoa; S. Petzold; P. Pfeifenschneider; J. E. Pilcher; J. Pinfold; D. E. Plane; P. Poffenberger; B. Poli; A. Posthaus; C. Rembser; S. Robertson; S. A. Robins; N. Rodning; J. M. Roney; A. Rooke; A. M. Rossi; P. Routenburg; Y. Rozen; K. Runge; O. Runolfsson; U. Ruppel; D. R. Rust; R. Rylko; K. Sachs; T. Saeki; W. M. Sang; E. K. G. Sarkisyan; C. Sbarra; A. D. Schaile; O. Schaile; F. Scharf; P. Scharff-Hansen; J. Schieck; P. Schleper; B. Schmitt; S. Schmitt; A. Schöning; M. Schröder; H. C. Schultz-Coulon; M. Schumacher; C. Schwick; W. G. Scott; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; G. P. Siroli; A. Sittler; A. Skillman; A. Skuja; A. M. Smith; G. A. Snow; R. Sobie; S. Söldner-Rembold; R. W. Springer; M. Sproston; K. Stephens; J. Steuerer; B. Stockhausen; K. Stoll; D. Strom; R. Ströhmer; P. Szymanski; R. Tafirout; S. D. Talbot; S. Tanaka; P. Taras; S. Tarem; R. Teuscher; M. Thiergen; M. A. Thomson; E. von Törne; E. Torrence; S. Towers; I. Trigger; Z. Trócsányi; E. Tsur; A. S. Turcot; M. F. Turner-Watson; P. Utzat; R. van Kooten; M. Verzocchi; P. Vikas; E. H. Vokurka; H. Voss; F. Wäckerle; A. Wagner; C. P. Ward; D. R. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; P. S. Wells; N. Wermes; J. S. White; B. Wilkens; G. W. Wilson; J. A. Wilson; T. R. Wyatt; S. Yamashita; G. Yekutieli; V. Zacek; D. Zer-Zion

1998-01-01

157

Lifetime measurements of the 7p levels of atomic francium  

Microsoft Academic Search

We present lifetime measurements of the 7p 2P3\\/2 and 7p 2 P1\\/2 levels of Fr. We use a time-correlated single-photon counting technique on a cold sample of 210Fr atoms in a magneto-optic trap. We excite the atoms with the trapping and repumping beams of the magneto-optic trap and detect the decay of the atomic fluores- cence. The results are a

J. E. Simsarian; L. A. Orozco; G. D. Sprouse; W. Z. Zhao

1998-01-01

158

Lifetime measurements of the 7D levels of atomic francium  

Microsoft Academic Search

We present lifetime measurements of the 7D3\\/2 and 7D5\\/2 levels of Fr. We use a time-correlated single- photon counting technique on a sample of 210Fr atoms confined and cooled in a magneto-optical trap. The upper state of the 7 P3\\/2 trapping transition serves as the resonant intermediate level for two-photon excitation of the 7D states. A probe laser provides the

J. M. Grossman; R. P. Fliller; L. A. Orozco III; M. R. Pearson; G. D. Sprouse

2000-01-01

159

A Precise measurement of the B0(s) lifetime  

SciTech Connect

The authors report a measurement of the B{sub s}{sup 0} lifetime in the semileptonic decay channel B{sub s}{sup 0} {yields} D{sub s}{sup -}{mu}{sup +}{nu}X (and its charge conjugate), using approximately 0.4 fb{sup -1} of data collected with the D0 detector during 2002-2004. They have reconstructed 5176 D{sub s}{sup -} {mu}{sup +} signal events, where the D{sub s}{sup -} is identified via the decay D{sub s}{sup 0} {yields} {phi}{pi}{sup -}, followed by {phi} {yields} K{sup +}K{sup -}. Using these events, they have measured the B{sub s}{sup 0} lifetime to be {tau}(B{sub s}{sup 0}) = 1.398 {+-} 0.044 (stat){sub -0.025}{sup +0.028}(syst) ps. This is the most precise measurement of the B{sub s}{sup 0} lifetime to date.

Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; /Buenos Aires U. /Rio de

2006-04-01

160

Spectral and lifetime domain measurements of rat brain tumors  

PubMed Central

During glioblastoma surgery, delineation of the brain tumor margins is difficult because the infiltrated and normal tissues have the same visual appearance. We use a fiber-optical fluorescence probe for spectroscopic and time domain measurements to assist surgeon in differentiating the healthy and the infiltrated tissues. First study was performed on rats that were previously injected with tumorous cells. Measurements of endogenous tissue fluorescence were performed on fresh and fixed rat tumor brain slices. Spectral characteristics, fluorescence redox ratios and fluorescence lifetime measurements were analyzed. The study aimed at defining an optical index that can act as an indicator for discriminating healthy from tumorous tissue.

Haidar, D. Abi; Leh, B.; Zanello, M.; Siebert, R.

2015-01-01

161

Probing the nanostructure of polymers via cryogenic Positron Annihilation Lifetime Spectroscopy (PALS)  

NASA Astrophysics Data System (ADS)

A new method is proposed for the evaluation of the hole volume in amorphous polymers based upon PALS data measured over a temperature of 110 to 480 K. Extrapolation of the "open hole" volume to 0 K allows its separation into that attributed to the segmental motions of the polymer chains (dynamic) and that due to inefficient packing (static). The dynamic hole volume is correlated to thermodynamic volume/density fluctuations and its temperature dependencies are in good agreement with SAXS data. Several thermosetting epoxy materials are also studied over a similar temperature range with the "open hole" volume being separated into its dynamic and static components. How these two components affect diffusional properties of these systems is examined in detail. It is also shown that the o-Ps can localize in a nearly 100material (PET), we therefore conclude that PALS measures more than the "free volume" necessary for segmental motion. Work supported by the Air Force Office of Scientific Research (AFOSR) grant # F49620-95-1-0037.

Bolan, B. A.; Soles, C. L.; Hristov, H. A.; Gidley, D. W.; Yee, A. F.

1996-03-01

162

Measurement of the Lifetime Difference in the Bs0 System  

Microsoft Academic Search

We present a study of the decay Bs0-->J\\/psivarphi. We obtain the CP-odd fraction in the final state at time zero, R?=0.16±0.10(stat)±0.02(syst), the average lifetime of the (Bs0, Bmacr s0) system, tau¯(Bs0)=1.39-0.16+0.13(stat)-0.02+0.01(syst)ps, and the relative width difference between the heavy and light mass eigenstates, DeltaGamma\\/Gamma¯?(GammaL-GammaH)\\/Gamma¯=0.24-0.38+0.28(stat)-0.04+0.03(syst). With the additional constraint from the world average of the Bs0 lifetime measurements using semileptonic decays,

V. M. Abazov; B. Abbott; M. Abolins; B. S. Acharya; M. Adams; T. Adams; M. Agelou; J.-L. Agram; S. H. Ahn; M. Ahsan; G. D. Alexeev; G. Alkhazov; A. Alton; G. Alverson; G. A. Alves; M. Anastasoaie; T. Andeen; S. Anderson; B. Andrieu; Y. Arnoud; M. Arov; A. Askew; B. Åsman; A. C. S. Assis Jesus; O. Atramentov; C. Autermann; C. Avila; F. Badaud; A. Baden; L. Bagby; B. Baldin; P. W. Balm; P. Banerjee; S. Banerjee; E. Barberis; P. Bargassa; P. Baringer; C. Barnes; J. Barreto; J. F. Bartlett; U. Bassler; D. Bauer; A. Bean; S. Beauceron; M. Begalli; M. Begel; A. Bellavance; S. B. Beri; G. Bernardi; R. Bernhard; I. Bertram; M. Besançon; R. Beuselinck; V. A. Bezzubov; P. C. Bhat; V. Bhatnagar; M. Binder; C. Biscarat; K. M. Black; I. Blackler; G. Blazey; F. Blekman; S. Blessing; D. Bloch; U. Blumenschein; A. Boehnlein; O. Boeriu; T. A. Bolton; F. Borcherding; G. Borissov; K. Bos; T. Bose; A. Brandt; R. Brock; G. Brooijmans; A. Bross; N. J. Buchanan; D. Buchholz; M. Buehler; V. Buescher; S. Burdin; S. Burke; T. H. Burnett; E. Busato; C. P. Buszello; J. M. Butler; J. Cammin; S. Caron; W. Carvalho; B. C. K. Casey; N. M. Cason; H. Castilla-Valdez; S. Chakrabarti; D. Chakraborty; K. M. Chan; A. Chandra; D. Chapin; F. Charles; E. Cheu; D. K. Cho; S. Choi; B. Choudhary; T. Christiansen; L. Christofek; D. Claes; B. Clément; C. Clément; Y. Coadou; M. Cooke; W. E. Cooper; D. Coppage; M. Corcoran; A. Cothenet; M.-C. Cousinou; B. Cox; S. Crépé-Renaudin; D. Cutts; H. da Motta; M. Das; B. Davies; G. Davies; G. A. Davis; K. de; P. de Jong; S. J. de Jong; E. de La Cruz-Burelo; C. de Oliveira Martins; S. Dean; J. D. Degenhardt; F. Déliot; M. Demarteau; R. Demina; P. Demine; D. Denisov; S. P. Denisov; S. Desai; H. T. Diehl; M. Diesburg; M. Doidge; H. Dong; S. Doulas; L. V. Dudko; L. Duflot; S. R. Dugad; A. Duperrin; J. Dyer; A. Dyshkant; M. Eads; D. Edmunds; T. Edwards; J. Ellison; J. Elmsheuser; V. D. Elvira; S. Eno; P. Ermolov; O. V. Eroshin; J. Estrada; H. Evans; A. Evdokimov; V. N. Evdokimov; J. Fast; S. N. Fatakia; L. Feligioni; A. V. Ferapontov; T. Ferbel; F. Fiedler; F. Filthaut; W. Fisher; H. E. Fisk; I. Fleck; M. Fortner; H. Fox; S. Fu; S. Fuess; T. Gadfort; C. F. Galea; E. Gallas; E. Galyaev; C. Garcia; A. Garcia-Bellido; J. Gardner; V. Gavrilov; A. Gay; P. Gay; D. Gelé; R. Gelhaus; K. Genser; C. E. Gerber; Y. Gershtein; D. Gillberg; G. Ginther; T. Golling; N. Gollub; B. Gómez; K. Gounder; A. Goussiou; P. D. Grannis; S. Greder; H. Greenlee; Z. D. Greenwood; E. M. Gregores; Ph. Gris; J.-F. Grivaz; L. Groer; S. Grünendahl; M. W. Grünewald; S. N. Gurzhiev; G. Gutierrez; P. Gutierrez; A. Haas; N. J. Hadley; S. Hagopian; I. Hall; R. E. Hall; C. Han; L. Han; K. Hanagaki; K. Harder; A. Harel; R. Harrington; J. M. Hauptman; R. Hauser; J. Hays; T. Hebbeker; D. Hedin; J. M. Heinmiller; A. P. Heinson; U. Heintz; C. Hensel; G. Hesketh; M. D. Hildreth; R. Hirosky; J. D. Hobbs; B. Hoeneisen; M. Hohlfeld; S. J. Hong; R. Hooper; P. Houben; Y. Hu; J. Huang; V. Hynek; I. Iashvili; R. Illingworth; A. S. Ito; S. Jabeen; M. Jaffré; S. Jain; V. Jain; K. Jakobs; A. Jenkins; R. Jesik; K. Johns; M. Johnson; A. Jonckheere; P. Jonsson; A. Juste; D. Käfer; S. Kahn; E. Kajfasz; A. M. Kalinin; J. Kalk; D. Karmanov; J. Kasper; I. Katsanos; D. Kau; R. Kaur; R. Kehoe; S. Kermiche; S. Kesisoglou; A. Khanov; A. Kharchilava; Y. M. Kharzheev; H. Kim; T. J. Kim; B. Klima; J. M. Kohli; J.-P. Konrath; M. Kopal; V. M. Korablev; J. Kotcher; B. Kothari; A. Koubarovsky; A. V. Kozelov; J. Kozminski; A. Kryemadhi; S. Krzywdzinski; Y. Kulik; A. Kumar; S. Kunori; A. Kupco; T. Kurca; J. Kvita; S. Lager; N. Lahrichi; G. Landsberg; J. Lazoflores; A.-C. Le Bihan; P. Lebrun; W. M. Lee; A. Leflat; F. Lehner; C. Leonidopoulos; J. Leveque; P. Lewis; J. Li; Q. Z. Li; J. G. R. Lima; D. Lincoln; S. L. Linn; J. Linnemann; V. V. Lipaev; R. Lipton; L. Lobo; A. Lobodenko; M. Lokajicek; A. Lounis; P. Love; H. J. Lubatti; L. Lueking; L. Luo; M. Lynker; A. L. Lyon; A. K. A. Maciel; R. J. Madaras; P. Mättig; C. Magass; A. Magerkurth; A.-M. Magnan; N. Makovec; P. K. Mal; H. B. Malbouisson; S. Malik; V. L. Malyshev; H. S. Mao; Y. Maravin; M. Martens; S. E. K. Mattingly; A. A. Mayorov; R. McCarthy; R. McCroskey; D. Meder; A. Melnitchouk; A. Mendes; D. Mendoza; M. Merkin; K. W. Merritt; A. Meyer; J. Meyer; M. Michaut; H. Miettinen; J. Mitrevski; J. Molina; N. K. Mondal; R. W. Moore; T. Moulik; G. S. Muanza; M. Mulders; L. Mundim; Y. D. Mutaf; E. Nagy; M. Naimuddin; M. Narain; N. A. Naumann; H. A. Neal; J. P. Negret; S. Nelson; P. Neustroev; C. Noeding; A. Nomerotski; S. F. Novaes; T. Nunnemann; E. Nurse; V. O'Dell; D. C. O'Neil; V. Oguri; N. Oliveira; N. Oshima; G. J. Otero Y Garzón; P. Padley; N. Parashar; S. K. Park; J. Parsons; R. Partridge; N. Parua; A. Patwa; G. Pawloski; P. M. Perea; E. Perez; P. Pétroff; M. Petteni; R. Piegaia; M.-A. Pleier

2005-01-01

163

CMS HF calorimeter PMTs and Xi(c)+ lifetime measurement  

SciTech Connect

This thesis consists of two parts: In the first part we describe the Photomultiplier Tube (PMT) selection and testing processes for the Hadronic Forward (HF) calorimeter of the CMS, a Large Hadron Collier (LHC) experiment at CERN. We report the evaluation process of the candidate PMTs from three different manufacturers, the complete tests performed on the 2300 Hamamatsu PMTs which will be used in the HF calorimeter, and the details of the PMT Test Station that is in University of Iowa CMS Laboratories. In the second part we report the {Xi}{sub c}{sup +} lifetime measurement from SELEX, the charm hadro-production experiment at Fermilab. Based upon 301 {+-} 31 events from three di.erent decay channels, by using the binned maximum likelihood technique, we observe the lifetime of {Xi}{sub c}{sup +} as 427 {+-} 31 {+-} 13 fs.

Akgun, Ugur; /Iowa U.

2003-12-01

164

Apparatus for measuring minority carrier lifetimes in semiconductor materials  

DOEpatents

An apparatus for determining the minority carrier lifetime of a semiconductor sample includes a positioner for moving the sample relative to a coil. The coil is connected to a bridge circuit such that the impedance of one arm of the bridge circuit is varied as sample is positioned relative to the coil. The sample is positioned relative to the coil such that any change in the photoconductance of the sample created by illumination of the sample creates a linearly related change in the input impedance of the bridge circuit. In addition, the apparatus is calibrated to work at a fixed frequency so that the apparatus maintains a consistently high sensitivity and high linearly for samples of different sizes, shapes, and material properties. When a light source illuminates the sample, the impedance of the bridge circuit is altered as excess carriers are generated in the sample, thereby producing a measurable signal indicative of the minority carrier lifetimes or recombination rates of the sample.

Ahrenkiel, Richard K. (Lakewood, CO)

1999-01-01

165

Bloodstain age analysis: toward solid state fluorescent lifetime measurements  

NASA Astrophysics Data System (ADS)

One of the most pressing unsolved challenges in forensic science is the determination of time since deposition (TSD) of bloodstains at crime scenes. Despite a number of high profile cases over the past couple hundred years involving controversy over TSD methods, no reliable quantitative method has been established. We present here an approach that has yet to be explored by forensic scientist: measuring the fluorescence lifetime of solid-state blood. Such a method would allow for on-site measurements of bloodstains utilizing the appropriate device, and would allow for rapid results returned in real-time to investigators.

Guo, Kevin; Zhegalova, Natalia; Achilefu, Samuel; Berezin, Mikhail Y.

2013-03-01

166

Free volume in imidazolium triflimide ([C{sub 3}MIM][NTf{sub 2}]) ionic liquid from positron lifetime: Amorphous, crystalline, and liquid states  

SciTech Connect

Positron annihilation lifetime spectroscopy (PALS) is used to study the ionic liquid 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide [C{sub 3}MIM][NTf{sub 2}] in the temperature range between 150 and 320 K. The positron decay spectra are analyzed using the routine LifeTime-9.0 and the size distribution of local free volumes (subnanometer-size holes) is calculated. This distribution is in good agreement with Fuerth's classical hole theory of liquids when taking into account Fuerth's hole coalescence hypothesis. During cooling, the liquid sample remains in a supercooled, amorphous state and shows the glass transition in the ortho-positronium (o-Ps) lifetime at 187 K. The mean hole volume varies between 70 A{sup 3} at 150 K and 250 A{sup 3} at 265-300 K. From a comparison with the macroscopic volume, the hole density is estimated to be constant at 0.20x10{sup 21} g{sup -1} corresponding to 0.30 nm{sup -3} at 265 K. The hole free volume fraction varies from 0.023 at 185 K to 0.073 at T{sub m}+12 K=265 K and can be estimated to be 0.17 at 430 K. It is shown that the viscosity follows perfectly the Cohen-Turnbull free volume theory when using the free volume determined here. The heating run clearly shows crystallization at 200 K by an abrupt decrease in the mean <{tau}{sub 3}> and standard deviation {sigma}{sub 3} of the o-Ps lifetime distribution and an increase in the o-Ps intensity I{sub 3}. The parameters of the second lifetime component <{tau}{sub 2}> and {sigma}{sub 2} behave parallel to the o-Ps parameters, which also shows the positron's (e{sup +}) response to structural changes. During melting at 253 K, all lifetime parameters recover to the initial values of the liquid. An abrupt decrease in I{sub 3} is attributed to the solvation of e{sup -} and e{sup +} particles. Different possible interpretations of the o-Ps lifetime in the crystalline state are briefly discussed.

Dlubek, G. [Institut fuer Physik, Martin-Luther-Universitaet Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120 Halle (Germany); ITA Institut fuer Innovative Technologien, Koethen/Halle, Wiesenring 4, D-06120 Lieskau (Germany); Yu, Yang; Krause-Rehberg, R. [Institut fuer Physik, Martin-Luther-Universitaet Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120 Halle (Germany); Beichel, W.; Bulut, S.; Pogodina, N.; Krossing, I.; Friedrich, Ch. [Freiburger Materialforschungszentrum (FMF), Albert-Ludwigs-Universitaet Freiburg, Stefan-Meier-Strasse 21, Germany and Institut fuer Anorganische Chemie, Albert-Ludwigs-Universitaet Freiburg, Albertstrasse 21, D-79104 Freiburg i. Br. (Germany)

2010-09-28

167

Positron interactions with water–total elastic, total inelastic, and elastic differential cross section measurements  

SciTech Connect

Utilising a high-resolution, trap-based positron beam, we have measured both elastic and inelastic scattering of positrons from water vapour. The measurements comprise differential elastic, total elastic, and total inelastic (not including positronium formation) absolute cross sections. The energy range investigated is from 1 eV to 60 eV. Comparison with theory is made with both R-Matrix and distorted wave calculations, and with our own application of the Independent Atom Model for positron interactions.

Tattersall, Wade [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia) [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia); Centre for Antimatter-Matter Studies, School of Engineering and Physical Sciences, James Cook University, Townsville, 4810 Queensland (Australia); Chiari, Luca [Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide 5001, South Australia (Australia)] [Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide 5001, South Australia (Australia); Machacek, J. R.; Anderson, Emma; Sullivan, James P. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)] [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia); White, Ron D. [Centre for Antimatter-Matter Studies, School of Engineering and Physical Sciences, James Cook University, Townsville, 4810 Queensland (Australia)] [Centre for Antimatter-Matter Studies, School of Engineering and Physical Sciences, James Cook University, Townsville, 4810 Queensland (Australia); Brunger, M. J. [Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide 5001, South Australia (Australia) [Centre for Antimatter-Matter Studies, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide 5001, South Australia (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Buckman, Stephen J. [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia) [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Garcia, Gustavo [Instituto de F?sica Fundamental, Consejo Superior de Investigationes Cient?ficas (CSIC), Serrano 113-bis, E-28006 Madrid (Spain)] [Instituto de F?sica Fundamental, Consejo Superior de Investigationes Cient?ficas (CSIC), Serrano 113-bis, E-28006 Madrid (Spain); Blanco, Francisco [Departamento de F?sica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain)] [Departamento de F?sica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain)

2014-01-28

168

The Lifetime of a beautiful and charming meson: B_c lifetime measured using the D0 detector  

SciTech Connect

Using approximately 1.3 fb{sup -1} of data collected by the D0 detector between 2002 and 2006, the lifetime of the B{sub c}{sup {+-}} meson is studied in the B{sub c}{sup {+-}} {yields} J/{psi}{mu}{sup {+-}} + X final state. Using an unbinned likelihood simultaneous fit to J/{psi} + {mu} invariant mass and lifetime distributions, a signal of 810 {+-} 80(stat.) candidates is estimated and a lifetime measurement made of: {tau}(B{sub c}{sup {+-}}) = 0.448{sub -0.036}{sup +0.038}(stat) {+-} 0.032(sys) ps.

Welty-Rieger, Leah Christine; /Indiana U.

2008-09-01

169

Improved measurement of the B 0 and B + meson lifetimes  

Microsoft Academic Search

The lifetimes of theB\\u000a 0 andB\\u000a + mesons have been measured with theAleph detector at LEP, using approximately 3 million hadronic Z decays collected in the period 1991–1994. In the first of three\\u000a methods, semileptonic decays ofB\\u000a 0 andB\\u000a + mesons were partially reconstructed by identifying events containing a lepton with an associatedD*? or$$\\\\bar D^0 $$ meson. The second method

D. Buskulic; I. De Bonis; D. Decamp; P. Ghez; C. Goy; J. P. Lees; A. Lucotte; M. N. Minard; P. Odier; B. Pietrzyk; M. Chmeissani; J. M. Crespo; M. Delfino; I. Efthymiopoulos; E. Fernandez; M. Fernandez-Bosman; L. Garrido; A. Juste; M. Martinez; S. Orteu; A. Pacheco; C. Padilla; A. Pascual; J. A. Perlas; I. Riu; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; G. Gelao; M. Girone; G. Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Nuzzo; A. Ranieri; G. Raso; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; R. Alemany; A. O. Bazarko; G. Bonvicini; M. Cattaneo; P. Comas; P. Coyle; H. Drevermann; R. W. Forty; M. Frank; R. Hagelberg; J. Harvey; P. Janot; B. Jost; E. Kneringer; J. Knobloch; I. Lehraus; E. B. Martin; P. Mato; A. Minten; R. Miquel; Ll. M. Mir; L. Moneta; T. Oest; F. Palla; J. R. Pater; J. F. Pusztaszeri; F. Ranjard; P. Rensing; L. Rolandi; D. Schlatter; M. Schmelling; O. Schneider; W. Tejessy; I. R. Tomalin; A. Venturi; H. Wachsmuth; A. Wagner; T. Wildish; Z. Ajaltouni; A. Barrès; C. Boyer; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J. C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; J. M. Rossignol; T. Fearnley; J. B. Hansen; J. D. Hansen; P. H. Hansen; B. S. Nilsson; A. Wäänänen; A. Kyriakis; C. Markou; E. Simopoulou; I. Siotis; A. Vayaki; K. Zachariadou; A. Blondel; G. Bonneaud; J. C. Brient; P. Bourdon; A. Rougé; M. Rumpf; A. Valassi; M. Verderi; H. Videau; D. J. Candlin; M. I. Parsons; E. Focardi; G. Parrini; M. Corden; C. Georgiopoulos; D. E. Jaffe; A. Antonelli; G. Bencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; D. Casper; V. Chiarella; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; L. Passalacqua; M. Pepe-Altarelli; L. Curtis; S. J. Dorris; A. W. Halley; I. G. Knowles; J. G. Lynch; V. O’Shea; C. Raine; P. Reeves; J. M. Scarr; K. Smith; A. S. Thompson; F. Thomson; S. Thorn; R. M. Turnbull; U. Becker; C. Geweniger; G. Graefe; P. Hanke; G. Hansper; V. Hepp; E. E. Kluge; A. Putzer; B. Rensch; M. Schmidt; J. Sommer; H. Stenzel; K. Tittel; S. Werner; M. Wunsch; D. Abbaneo; R. Beuselinck; D. M. Binnie; W. Cameron; P. J. Dornan; A. Moutoussi; J. Nash; J. K. Sedgbeer; A. M. Stacey; M. D. Williams; G. Dissertori; P. Girtler; D. Kuhn; G. Rudolph; A. P. Betteridge; C. K. Bowdery; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; T. Sloan; M. I. Williams; A. Galla; A. M. Greene; K. Kleinknecht; G. Quast; B. Renk; E. Rohne; H. G. Sander; P. van Gemmeren; C. Zeitnitz; J. J. Aubert; A. M. Bencheikh; C. Benchouk; A. Bonissent; G. Bujosa; D. Calvet; J. Carr; C. Diaconu; F. Etienne; N. Konstantinidis; P. Payre; D. Rousseau; M. Talby; A. Sadouki; M. Thulasidas; K. Trabelsi; M. Aleppo; F. Ragusa; I. Abt; R. Assmann; C. Bauer; W. Blum; H. Dietl; F. Dydak; G. Ganis; C. Gotzhein; K. Jakobs; H. Kroha; G. Lütjens; G. Lutz; W. Männer; H. G. Moser; R. Richter; A. Rosado-Schlosser; S. Schael; R. Settles; H. Seywerd; R. St. Denis; W. Wiedenmann; G. Wolf; J. Boucrot; O. Callot; A. Cordier; M. Davier; L. Duflot; J. F. Grivaz; Ph. Heusse; M. Jacquet; D. W. Kim; F. Le Diberder; J. Lefrançois; A. M. Lutz; I. Nikolic; H. J. Park; I. C. Park; M. H. Schune; S. Simion; J. J. Veillet; I. Videau; P. Azzurri; G. Bagliesi; G. Batignani; S. Bettarini; C. Bozzi; G. Calderini; M. Carpinelli; M. A. Ciocci; V. Ciulli; R. Dell’Orso; R. Fantechi; I. Ferrante; L. Foà; F. Forti; A. Giassi; M. A. Giorgi; A. Gregorio; F. Ligabue; A. Lusiani; P. S. Marrocchesi; A. Messineo; G. Rizzo; G. Sanguinetti; A. Sciabà; P. Spagnolo; J. Steinberger; R. Tenchini; G. Tonelli; C. Vannini; P. G. Verdini; J. Walsh; G. A. Blair; L. M. Bryant; F. Cerutti; J. T. Chambers; Y. Gao; M. G. Green; T. Medcalf; P. Perrodo; J. A. Strong; J. H. von Wimmersperg-Toeller; D. R. Botterill; R. W. Clifft; T. R. Edgecock; S. Haywood; P. Maley; P. R. Norton; J. C. Thompson; A. E. Wright; B. Bloch-Devaux; P. Colas; S. Emery; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; B. Marx; P. Perez; J. Rander; J. F. Renardy; A. Roussarie; J. P. Schuller; J. Schwindling; A. Trabelsi; B. Vallage; S. N. Black; J. H. Dann; R. P. Johnson; H. Y. Kim; A. M. Litke; M. A. McNeil; G. Taylor; C. N. Booth; R. Boswell; C. A. J. Brew; S. Cartwright; F. Combley; A. Koksal; M. Letho; W. M. Newton; J. Reeve; L. F. Thompson; A. Böhrer; S. Brandt; V. Büscher; G. Cowan; C. Grupen; G. Lutters; J. Minguet-Rodriguez; F. Rivera; P. Saraiva; L. Smolik; F. Stephan; M. Apollonio; L. Bosisio; R. Della Marina; G. Giannini; B. Gobbo; G. Musolino; J. Rothberg; S. Wasserbaech; S. R. Armstrong; L. Bellantoni; P. Elmer; Z. Feng; D. P. S. Ferguson; S. González; J. Grahl; T. C. Greening; J. L. Harton; O. J. Hayes; H. Hu; P. A. McNamara; J. M. Nachtman; W. Orejudos; Y. B. Pan; Y. Saadi

1996-01-01

170

Electron Beam Lifetime in SPEAR3: Measurement and Simulation  

SciTech Connect

In this paper we report on electron beam lifetime measurements as a function of scraper position, RF voltage and bunch fill pattern in SPEAR3. We then outline development of an empirical, macroscopic model using the beam-loss rate equation. By identifying the dependence of loss coefficients on accelerator and beam parameters, a numerically-integrating simulator can be constructed to compute beam decay with time. In a companion paper, the simulator is used to train a parametric, non-linear dynamics model for the system [1].

Corbett, J.; Huang, X.; Lee, M.; Lui, P.; /SLAC; Sayyar-Rodsari, B.; /Pavilon Tech., Austin

2007-12-19

171

Measurements of ultracold neutron lifetimes in solid deuterium  

E-print Network

We present the first measurements of the survival time of ultracold neutrons (UCNs) in solid deuterium SD2. This critical parameter provides a fundamental limitation to the effectiveness of superthermal UCN sources that utilize solid ortho-deuterium as the source material. Superthermal UCN sources offer orders of magnitude improvement in the available densities of UCNs, and are of great importance to fundamental particle-physics experiments such as searches for a static electric dipole moment and lifetime measurements of the free neutron. These measurements are performed utilizing a SD2 source coupled to a spallation source of neutrons, providing a demonstration of UCN production in this geometry and permitting systematic studies of the influence of thermal up-scatter and contamination with para-deuterium on the UCN survival time.

C. L. Morris; J. M. Anaya; T. J. Bowles; B. W. Filippone; P. Geltenbort; R. E. Hill; M. Hino; S. Hoedl; G. E. Hogan; T. M. Ito; T. Kawai; K. Kirch; S. K. Lamoreaux; C. -Y. Liu; M. Makela; L. J. Marek; J. W. Martin; R. N. Mortensen; A. Pichlmaier; A. Saunders; S. J. Seestrom; D. Smith; W. Teasdale; B. Tipton; M. Utsuro; A. R. Young; J. Yuan

2001-09-28

172

A New Measurement of the Muon Lifetime with the MuLan Experiment  

Microsoft Academic Search

Following recent theoretical calculations, the uncertainty on the Fermi coupling constant is now limited by the precision with which the muon lifetime is measured. The current world average uncertainty on the lifetime is 17 ppm. The MuLan experiment is designed to measure the muon lifetime to 1 ppm. To supply muons, a periodic, pulsed muon beam is created. During a

Josh Kunkle

2006-01-01

173

Positron annihilation Investigations of defects in copper alloys selected for nuclear fusion technology  

Microsoft Academic Search

A positron annihilation spectroscopy (PAS) based on positron lifetime measurements, using the pulsed low energy positron system (PLEPS), is used to investigate defects create by hydrogen implantation and thermal treat of copper alloys. These alloys are designated for the use in the international thermonuclear experimental reactor (ITER). The results show that the changes in the microstructure of selected copper alloys

V Slugen; J Kuriplach; P Ballo; P Domonkos; G Kögel; P Sperr; W Egger; W Triftshäuser; V. M Domankova; P Kovac; I Vavra; S Stancek; M Petriska; A Zeman

2004-01-01

174

Measurements of Total Cross Sections for Positrons and Electrons Colliding with Atomic Hydrogen and Measurements of Positronium Formation Cross Sections for Positron-Argon and - Scattering  

Microsoft Academic Search

We have made the first measurements of total cross sections for 5 to 302 eV positrons and 31 to 302 eV electrons scattered by atomic hydrogen. A beam-transmission technique is used where the positron and electron beam passes through a low temperature scattering cell containing a mixture of hydrogen atoms and molecules generated in an adjacent radio-frequency discharge region. We

Shangjing Zhou

1993-01-01

175

The “accumulation effect” of positrons in the stack of foils, detected by measurements of the positron implantation profile  

SciTech Connect

The profiles of positrons implanted from the radioactive source {sup 22}Na into a stack of foils and plates are the subject of our experimental and theoretical studies. The measurements were performed using the depth scanning of positron implantation profile method, and the theoretical calculations using the phenomenological multi-scattering model (MSM). Several stacks consisting of silver, gold and aluminum foils, and titanium and germanium plates were investigated. We notice that the MSM describes well the experimental profiles; however when the stack consisting of silver and gold foils, the backscattering and linear absorption coefficients differ significantly from those reported in the literature. We suggest the energy dependency of the backscattering coefficient for silver and gold. In the stacks which comprise titanium and germanium plates, there were observed the features, which indicate the presence of the “accumulation effect” in the experimental implantation profile. This effect was previously detected in implantation profiles in Monte Carlo simulations using the GEANT4 tool kit, and it consists in higher localization of positrons close the interface. We suppose that this effect can be essential for positron annihilation in any heterogeneous materials.

Dryzek, Jerzy [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland); Institute of Physics, Opole University, ul. Oleska 48, 45-052 Opole (Poland); Siemek, Krzysztof [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland)

2013-12-14

176

The ``accumulation effect'' of positrons in the stack of foils, detected by measurements of the positron implantation profile  

NASA Astrophysics Data System (ADS)

The profiles of positrons implanted from the radioactive source 22Na into a stack of foils and plates are the subject of our experimental and theoretical studies. The measurements were performed using the depth scanning of positron implantation profile method, and the theoretical calculations using the phenomenological multi-scattering model (MSM). Several stacks consisting of silver, gold and aluminum foils, and titanium and germanium plates were investigated. We notice that the MSM describes well the experimental profiles; however when the stack consisting of silver and gold foils, the backscattering and linear absorption coefficients differ significantly from those reported in the literature. We suggest the energy dependency of the backscattering coefficient for silver and gold. In the stacks which comprise titanium and germanium plates, there were observed the features, which indicate the presence of the "accumulation effect" in the experimental implantation profile. This effect was previously detected in implantation profiles in Monte Carlo simulations using the GEANT4 tool kit, and it consists in higher localization of positrons close the interface. We suppose that this effect can be essential for positron annihilation in any heterogeneous materials.

Dryzek, Jerzy; Siemek, Krzysztof

2013-12-01

177

First $?K$ atom lifetime and $?K$ scattering length measurements  

E-print Network

The results of a search for hydrogen-like atoms consisting of $\\pi^{\\mp}K^{\\pm}$ mesons are presented. Evidence for $\\pi K$ atom production by 24 GeV/c protons from CERN PS interacting with a nickel target has been seen in terms of characteristic $\\pi K$ pairs from their breakup in the same target ($178 \\pm 49$) and from Coulomb final state interaction ($653 \\pm 42$). Using these results the analysis yields a first value for the $\\pi K$ atom lifetime of $\\tau=(2.5_{-1.8}^{+3.0})$ fs and a first model-independent measurement of the S-wave isospin-odd $\\pi K$ scattering length $\\left|a_0^-\\right|=\\frac{1}{3}\\left|a_{1/2}-a_{3/2}\\right|= \\left(0.11_{-0.04}^{+0.09} \\right)M_{\\pi}^{-1}$ ($a_I$ for isospin $I$).

B. Adeva; L. Afanasyev; Y. Allkofer; C. Amsler; A. Anania; S. Aogaki; A. Benelli; V. Brekhovskikh; T. Cechak; M. Chiba; P. Chliapnikov; C. Ciocarlan; S. Constantinescu; P. Doskarova; D. Drijard; A. Dudarev; M. Duma; D. Dumitriu; D. Fluerasu; A. Gorin; O. Gorchakov; K. Gritsay; C. Guaraldo; M. Gugiu; M. Hansroul; Z. Hons; S. Horikawa; Y. Iwashita; V. Karpukhin; J. Kluson; M. Kobayashi; V. Kruglov; L. Kruglova; A. Kulikov; E. Kulish; A. Kuptsov; A. Lamberto; A. Lanaro; R. Lednicky; C. Mariñas; J. Martincik; L. Nemenov; M. Nikitin; K. Okada; V. Olchevskii; M. Pentia; A. Penzo; M. Plo; T. Ponta; P. Prusa; G. Rappazzo; A. Romero Vidal; A. Ryazantsev; V. Rykalin; J. Schacher; A. Sidorov; J. Smolik; S. Sugimoto; F. Takeutchi; L. Tauscher; T. Trojek; S. Trusov; T. Urban; T. Vrba; V. Yazkov; Y. Yoshimura; M. Zhabitsky; P. Zrelov

2014-03-04

178

Measuring early or late dependence for bivariate lifetimes of twins.  

PubMed

We consider data from the Danish twin registry and aim to study in detail how lifetimes for twin-pairs are correlated. We consider models where we specify the marginals using a regression structure, here Cox's regression model or the additive hazards model. The best known such model is the Clayton-Oakes model. This model can be extended in several directions. One extension is to allow the dependence parameter to depend on covariates. Another extension is to model dependence via piecewise constant cross-hazard ratio models. We show how both these models can be implemented for large sample data, and suggest a computational solution for obtaining standard errors for such models for large registry data. In addition we consider alternative models that have some computational advantages and with different dependence parameters based on odds ratios of the survival function using the Plackett distribution. We also suggest a way of assessing how and if the dependence is changing over time, by considering either truncated or right-censored versions of the data to measure late or early dependence. This can be used for formally testing if the dependence is constant, or decreasing/increasing. The proposed procedures are applied to Danish twin data to describe dependence in the lifetimes of the twins. Here we show that the early deaths are more correlated than the later deaths, and by comparing MZ and DZ associations we suggest that early deaths might be more driven by genetic factors. This conclusion requires models that are able to look at more local dependence measures. We further show that the dependence differs for MZ and DZ twins and appears to be the same for males and females, and that there are indications that the dependence increases over calendar time. PMID:25185657

Scheike, Thomas H; Holst, Klaus K; Hjelmborg, Jacob B

2015-04-01

179

c, b, and tau lifetime measurements in e/sup +/e/sup -/ interactions  

SciTech Connect

Experiments at e/sup +/e/sup -/ storage rings have successfully measured the tau and D/sup 0/ lifetimes and set interesting limits on the B lifetime. So far, the conventional wisdom has prevailed. The tau lifetime is consistent with prediction; there is no sign (but little sensitivity) of a violation of universality. The charmed particle lifetimes are roughly as expected, but richer in their phenomenology than anticipated. The B lifetime is still unknown. The experimental art is developing rapidly. Several experiments have by now installed vertex detectors. Measurements of charmed particle lifetimes from e/sup +/e/sup -/ experiments will complement the work that has been done at fixed target machines. Measurements of tau and B lifetimes may be the exclusive province of e/sup +/e/sup -/ experiments for the next few years. (WHK)

Jaros, J.A.

1983-01-01

180

Construction of concentration density profile across the interface in SAN/EVA immiscible blend from positron lifetime parameters  

NASA Astrophysics Data System (ADS)

The interface width determination through the construction of composition density profile across the interface in an immiscible binary polymer blend using ortho-positronium lifetime parameters is described in this paper. The distribution of free volume and hence the hydrodynamic interaction parameter has been evaluated for this purpose making use of the CONTIN routine analysis of the lifetime spectra. The results showed the broad free volume distribution and narrow interface width were reminiscent of lack of interaction between SAN and EVA the constituents.

Ramya, P.; Meghala, D.; Pasang, T.; Ranganathaiah, C.

2013-02-01

181

Applications of positron annihilation spectroscopy in materials research  

NASA Technical Reports Server (NTRS)

Positron Annihilation Spectroscopy (PAS) has emerged as a powerful technique for research in condensed matter. It has been used extensively in the study of metals, ionic crystals, glasses and polymers. The present review concentrates on applications of positron lifetime measurements for elucidation of the physicochemical structure of polymers.

Singh, Jag J.

1988-01-01

182

Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime Using Controlled Calorimetry  

SciTech Connect

A comprehensive description of the accomplishments of the DOE grant titled, ''Local Measurement of Fuel Energy Deposition and Heat Transfer Environment During Fuel Lifetime using Controlled Calorimetry''.

Don W. Miller; Andrew Kauffmann; Eric Kreidler; Dongxu Li; Hanying Liu; Daniel Mills; Thomas D. Radcliff; Joseph Talnagi

2001-12-31

183

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01  

E-print Network

A measurement of the cosmic ray positron fraction e+/(e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10^6 is reached by identifying converted bremsstrahlung photons emitted from positrons.

AMS-01 Collaboration

2007-03-27

184

Measurement of the Charged and Neutral D Meson Lifetimes.  

NASA Astrophysics Data System (ADS)

In an exposure of the SLAC Hybrid Facility (SHF) to a backward scattered laser beam, 136 charm events produced in (gamma)p interactions at 20 GeV have been observed. The SHF 1 m bubble chamber was equipped with a High Resolution Optics camera in order to detect directly the production and decay of charm particles. After imposing rigorous cuts, 48 charged, 50 neutral,and 2 topologically ambiguous decays remain. Using a novel method for estimating the momentum. of unconstrained decays, the D meson lifetimes from this sample are measured to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). and (tau)(,D)('0)= (6.1 (+OR-) 0.9 (+OR-) 0.3) x 10('-13) sec with a ratio of. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). This value of R indicates the Spectator Model charm particle decay mechanism is the dominate piece in the D('(+OR-)) and D('0) decay rates. Limits are placed on additional contributions to the D decay rates from other processes including W-Exchange, Final State Inter- actions, and Pauli Principle Interference.

Butler, John Mark

185

Measurement of the charged and neutral D meson lifetimes  

SciTech Connect

In an exposure of the SLAC Hybrid Facility (SHF) to a backward scattered laser beam, 136 charm events produced in ..gamma..p interactions at 20 GeV have been observed. The SHF 1 m bubble chamber was equipped with a High Resolution Optics camera in order to detect directly the production and decay of charm particles. After imposing rigorous cuts, 48 charged, 50 neutral, and 2 topologically ambiguous decays remain. Using a novel method for estimating the momentum of unconstrained decays, the D meson lifetimes from this sample are measured to be tau/sub D sup +-/ = (8.6 +- 1.3/sub -0.3//sup +0.8/) x 10/sup -13/ sec and tau/sub D/sup 0// = (6.1 +- 0.9 +- 0.3) x 10/sup -13/ sec with a ratio of R = tau/sub D sup +-//tau/sub D/sup 0// = (1.4 +- 0.3/sub -0.1//sup +0.2/). This value of R indicates the Spectator Model charm particle decay mechanism is the dominate piece in the D/sub +-/ and D/sup 0/ decay rates. Limits are placed on additional contributions to the D decay rates from other processes including W-Exchange, Final State Interactions, and Pauli Principle Interference. 34 refs., 41 figs.

Butler, J.M.

1986-02-01

186

A novel approach to investigate bulk carrier lifetime using low frequency fluctuation noise measurement  

NASA Astrophysics Data System (ADS)

The carrier lifetime of silicon wafer-based solar cells is measured by a newly proposed novel approach—inference from low frequency noise (1/f) fluctuations. Our derived carrier lifetime calculation formula conforms well to standard 1/f behavior, which mathematically validates our model. Without a priori information about the material parameters e.g. dopant concentration etc, 1/f noise measurement is able to conclude the average carrier lifetime with accuracy comparable to conventional quasi steady state optical methods. The carrier lifetime model is potentially beneficial in characterizing bulk-state solar cells and can be extended further to the packaged devices where the pulse light decay signal measurement is difficult.

Lin, Ke; Hongwei, Liu; Szu Cheng, Lai; Sha, Huang; Hoex, Bram; Chua, Soo Jin; Xiao Wei, Sun

2014-12-01

187

Quinhydrone/Methanol Treatment for the Measurement of Carrier Lifetime in Silicon Substrates  

NASA Astrophysics Data System (ADS)

Quinhydrone/methanol treatment for the measurement of carrier lifetime in crystalline silicon substrates has been investigated. To estimate the surface passivation effect, the lifetimes of the silicon substrates were measured using the microwave photoconductive decay method. The measured lifetime is dependent on quinhydrone concentration and passivation time. The 0.01 mol/dm3 quinhydrone/methanol treatment exhibited a good passivation effect, and a very low surface recombination velocity was obtained. The quinhydrone/methanol treatment can provide a reliable lifetime map of silicon wafers since a constant lifetime value without degradation can be obtained. Therefore, the quinhydrone/methanol treatment can be used for estimating the bulk lifetime of silicon substrates.

Takato, Hidetaka; Sakata, Isao; Shimokawa, Ryuichi

2002-08-01

188

Measurements of solder bump lifetime as a function of underfill material properties  

Microsoft Academic Search

This paper presents measurements of the number of thermal cycles to failure for eutectic solder bumps in flip-chip-on-board (FCOB) circuits with and without underfill. The bump lifetimes are measured as a function of the distance to the chip centre for two different underfill materials. The results show that the lifetime of the solder bumps under thermal cycling from -55 to

J. B. Nysaether; P. Lundstrom; J. Liu

1998-01-01

189

Microstructural Characterization of Polymers with Positrons  

NASA Technical Reports Server (NTRS)

Positrons provide a versatile probe for monitoring microstructural features of molecular solids. In this paper, we report on positron lifetime measurements in two different types of polymers. The first group comprises polyacrylates processed on earth and in space. The second group includes fully-compatible and totally-incompatible Semi-Interpenetrating polymer networks of thermosetting and thermoplastic polyimides. On the basis of lifetime measurements, it is concluded that free volumes are a direct reflection of physical/electromagnetic properties of the host polymers.

Singh, Jag J.

1997-01-01

190

Lifetime and diffusion length measurements on silicon material and solar cells  

NASA Technical Reports Server (NTRS)

Experimental methods were evaluated for the determination of lifetime and diffusion length in silicon intentionally doped with potentially lifetime-degrading impurities found in metallurgical grade silicon, impurities which may be residual in low-cost silicon intended for use in terrestrial flat-plate arrays. Lifetime measurements were made using a steady-state photoconductivity method. Diffusion length determinations were made using short-circuit current measurements under penetrating illumination. Mutual consistency among all experimental methods was verified, but steady-state photoconductivity was found preferable to photoconductivity decay at short lifetimes and in the presence of traps. The effects of a number of impurities on lifetime in bulk material, and on diffusion length in cells fabricated from this material, were determined. Results are compared with those obtained using different techniques. General agreement was found in terms of the hierarchy of impurities which degrade the lifetime.

Othmer, S.; Chen, S. C.

1978-01-01

191

Measuring the efficiency of the Texas A&M Positron Emission Tomograph  

E-print Network

MEASURIVG THE EFFICIENC'r OF THE TEXAS ARM POSITRON EMISSION TOMOGRAPH A Thesis by WESLEY BLAKE LOEWER Submitted to the Graduate College of Texas AklVI University in partial fulfdlment of the requirements for the degree of MASTER OF SCIENCE... watson (Member) l )'~ Richard Arnowitt (Head oi' Department) May 1988 111 ABSTRACT Measuring the Efficiency of the Texas AkM Positron Emission Tomograph. (May 1988) W'esley Blake Loewer, B. S. , Wheaton College Chairman of Advisory Committee: Dr...

Loewer, Wesley Blake

1988-01-01

192

Measurement of the Average B Hadron Lifetime Using Reconstructed Vertices in Three-Dimensions  

SciTech Connect

This thesis describes a measurement of the average B hadron lifetime using data collected with the SLD detector at the Stanford Linear Collider in 1993. An inclusive analysis selects three dimensional vertices with B hadron lifetime information in a sample of 50,000 Z{sup 0} decays. A lifetime of 1.564 {+-} 0.030(stat) {+-} 0.036(syst) ps is extracted from the decay length distribution of these vertices using a binned maximum likelihood method.

Sen, S

2003-12-17

193

Measurement of the average B hadron lifetime in Z0 decays using reconstructed vertices  

Microsoft Academic Search

We report a measurement of the average B hadron lifetime using data collected with the SLD detector at the SLAC Linear Collider in 1993. An inclusive analysis selected three-dimensional vertices with B hadron lifetime information in a sample of 50×103 Z0 decays. A lifetime of 1.564+\\/-0.030(stat)+\\/-0.036(syst) ps was extracted from the decay length distribution of these vertices using a binned

K. Abe; I. Abt; C. J. Ahn; T. Akagi; N. J. Allen; W. W. Ash; D. Aston; K. G. Baird; C. Baltay; H. R. Band; M. B. Barakat; G. Baranko; O. Bardon; T. Barklow; A. O. Bazarko; R. Ben-David; A. C. Benvenuti; G. M. Bilei; D. Bisello; G. Blaylock; J. R. Bogart; T. Bolton; G. R. Bower; J. E. Brau; M. Breidenbach; W. M. Bugg; D. Burke; T. H. Burnett; P. N. Burrows; W. Busza; A. Calcaterra; D. O. Caldwell; D. Calloway; B. Camanzi; M. Carpinelli; R. Cassell; R. Castaldi; A. Castro; M. Cavalli-Sforza; E. Church; H. O. Cohn; J. A. Coller; V. Cook; R. Cotton; R. F. Cowan; D. G. Coyne; A. D'oliveira; C. J. Damerell; M. Daoudi; R. de Sangro; P. de Simone; R. dell'orso; M. Dima; P. Y. Du; R. Dubois; B. I. Eisenstein; R. Elia; D. Falciai; C. Fan; M. J. Fero; R. Frey; K. Furuno; T. Gillman; G. Gladding; S. Gonzalez; G. D. Hallewell; E. L. Hart; Y. Hasegawa; S. Hedges; S. S. Hertzbach; M. D. Hildreth; J. Huber; M. E. Huffer; E. W. Hughes; H. Hwang; Y. Iwasaki; D. J. Jackson; P. Jacques; J. Jaros; A. S. Johnson; J. R. Johnson; R. A. Johnson; T. Junk; R. Kajikawa; M. Kalelkar; H. J. Kang; I. Karliner; H. Kawahara; H. W. Kendall; Y. Kim; M. E. King; R. King; R. R. Kofler; N. M. Krishna; R. S. Kroeger; J. F. Labs; M. Langston; A. Lath; J. A. Lauber; D. W. Leith; M. X. Liu; X. Liu; M. Loreti; A. Lu; H. L. Lynch; J. Ma; G. Mancinelli; S. Manly; G. Mantovani; T. W. Markiewicz; T. Maruyama; R. Massetti; H. Masuda; E. Mazzucato; A. K. McKemey; B. T. Meadows; R. Messner; P. M. Mockett; K. C. Moffeit; B. Mours; G. Müller; D. Muller; T. Nagamine; U. Nauenberg; H. Neal; M. Nussbaum; Y. Ohnishi; L. S. Osborne; R. S. Panvini; T. J. Pavel; I. Peruzzi; M. Piccolo; L. Piemontese; E. Pieroni; K. T. Pitts; R. J. Plano; R. Prepost; C. Y. Prescott; G. D. Punkar; J. Quigley; B. N. Ratcliff; T. W. Reeves; J. Reidy; P. E. Rensing; L. S. Rochester; J. E. Rothberg; P. C. Rowson; J. J. Russell; O. H. Saxton; S. F. Schaffner; T. Schalk; R. H. Schindler; U. Schneekloth; B. A. Schumm; A. Seiden; S. Sen; V. V. Serbo; M. H. Shaevitz; J. T. Shank; G. Shapiro; S. L. Shapiro; D. J. Sherden; K. D. Shmakov; C. Simopoulos; N. B. Sinev; S. R. Smith; J. A. Snyder; P. Stamer; H. Steiner; R. Steiner; M. G. Strauss; D. Su; F. Suekane; A. Sugiyama; S. Suzuki; M. Swartz; A. Szumilo; T. Takahashi; F. E. Taylor; E. Torrence; A. I. Trandafir; J. D. Turk; T. Usher; J. Va'vra; C. Vannini; E. Vella; J. P. Venuti; R. Verdier; P. G. Verdini; S. R. Wagner; A. P. Waite; S. J. Watts; A. W. Weidemann; E. R. Weiss; J. S. Whitaker; S. L. White; F. J. Wickens; D. A. Williams; S. H. Williams; S. Willocq; R. J. Wilson; W. J. Wisniewski; M. Woods; G. B. Word; J. Wyss; R. K. Yamamoto; J. M. Yamartino; X. Yang; S. J. Yellin; C. C. Young; H. Yuta; G. Zapalac; R. W. Zdarko; C. Zeitlin; Z. Zhang; J. Zhou

1995-01-01

194

A Monte-Carlo simulation of positron diffusion in solids  

NASA Astrophysics Data System (ADS)

A Monte-Carlo simulation of positron diffusion in layered structures is described. This simulation is a useful tool to extract physical properties of slow positron data. The basis of the simulation is the random-walk model of the positron diffusion (C. Hübner, T. Staab and R. Krause-Rehberg, Appl. Phys. A 61 (1995) 203) [1]. The input parameters are the temperature, the positron diffusion constants, the positron lifetimes, the positron trapping rates, and the S parameters of bulk and defect annihilation. Furthermore, assumptions on the sample layer structure, the properties of surface and interfaces, the structure of the electric field, and the positron implantation profile must be included. The results of the simulation are the S parameter, F parameter, or positron lifetimes as a function of positron implantation energy, respectively. This means that a real positron beam experiment is simulated. The resulted data can directly be compared to measured curves. A typical simulation of layered structures, such as a Schottky contact (Au-film on Si), was performed, and the data were compared with experimental data of the literature. Furthermore, we studied the effect of internal and external electric fields on defect profiling in semiconductors by slow positron beam technique.

Eichler, S.; Hübner, C.; Krause-Rehberg, R.

1997-05-01

195

Net merit as a measure of lifetime profit: 2010 revision  

Technology Transfer Automated Retrieval System (TEKTRAN)

The 2010 revision of net merit (NM$) updates a number of key economic values as well as milk utilization statistics. Members of Project S-1040, Genetic Selection and Crossbreeding To Enhance Reproduction and Survival of Dairy Cattle, provided updated incomes and expenses used to estimate lifetime pr...

196

Lifetime measurements of electron-cyclotron-resonance-heated electrons  

Microsoft Academic Search

The lifetime of energetic electrons generated via second harmonic electron-cyclotron-resonance heating in a symmetric magnetic mirror configuration is investigated experimentally. The decay time is observed to be as much as a factor of 4 shorter than the value calculated for the most rapid classical loss mechanism, Coulomb drag. The nonclassical loss component is shown to be induced by the microwave

H. Boehmer; H. Goede; S. Talmadge

1985-01-01

197

An Undergraduate Experiment for the Measurement of Phosphorescence Lifetimes  

ERIC Educational Resources Information Center

Describes an experiment which monitors the population of the lowest triplet state by directly observing phosphorescence intensity as a function of time. Reviews the theory concerning triplet state lifetimes, describes the experimental apparatus and procedure, and presents the method and examples of data analysis. (GS)

Dyke, Thomas R.; Muenter, J. S.

1975-01-01

198

Cosmic ray positron and negatron spectra between 20 and 800 MeV measured in 1974  

NASA Technical Reports Server (NTRS)

A balloon-borne spark chamber magnetic spectrometer was used to measure separate spectra of positrons and negatrons in two flights during summer, 1974. The total electron flux is about 0.3 m(-2) s(-1) sr(-1) MeV(-1) between 70 and 800 MeV, and increases toward lower energies. The positron spectrum decreases sharply toward lower energies from a value of about 0.08 m(-2) s(-1) sr(-1) MeV(-1) at 650 MeV, and only upper limits are obtained for positrons below 200 MeV. At energies above 180 MeV, the spherically symmetric Fokker-Planck equation provides reasonable fits to both the positron and total electron data. At energies below 180 MeV the data are consistent with a continuation of the same diffusion coefficient and local source of negatrons, or a change in the diffusion coefficient to a constant value.

Hartman, R. C.; Pellerin, C. J.

1975-01-01

199

Measuring vibrational coherence lifetimes in liquid methanol using transient coherent Raman scattering  

NASA Astrophysics Data System (ADS)

We demonstrate the measurement of vibrational coherence in liquids using transient coherent Raman scattering. This technique measures the coherence lifetime of vibrational states through the interference of time-delayed coherent Raman-scattered photons using low-power, non-resonant optical pulses. We measure the vibrational lifetime of the 1033 cm-1 mode in liquid methanol. The resulting lifetime agrees with frequency-domain lineshape measurements. This technique is a complementary and in some cases simpler alternative to standard nonlinear spectroscopy techniques.

Meiselman, S.; Cohen, O.; DeCamp, M. F.; Lorenz, V. O.

2014-04-01

200

Betatron phase and coupling measurements at the Cornell Electron\\/Positron Storage Ring  

Microsoft Academic Search

Measurement of the betatron phase in the vertical and horizontal planes as well as the transverse horizontal-vertical coupling is a standard procedure now used at the Cornell Electron\\/Positron Storage Ring. The measurement is made by shaking the beam and observing the phase of oscillation at detectors located around the ring. The measurements allow quadrupolar errors to be corrected.

D. Sagan; R. Meller; R. Littauer; D. Rubin

2000-01-01

201

Picosecond fluorescence lifetime measurements on dyes adsorbed at semiconductor and insulator surfaces  

SciTech Connect

Fluorescence lifetimes in the 50 to 60-ps range were measured for rhodamine B and eosin adsorbed on tin oxide and indium oxide surfaces. Somewhat shorter lifetimes were obtained for rhodamine B adsorbed on plain glass. Implications these results have for models of the dye-sensitized photoinjection into semiconductors are discussed.

Liang, Y. (Temple Univ., Philadelphia, PA); Ponte Goncalves, A.M.; Negus, D.K.

1983-01-06

202

A method to increase scintillation lifetime measurement rates using a multi-hit TDC  

Microsoft Academic Search

Summary form only. A method for using a modern TDC (time-to-digital converter) to increase the scintillation lifetime measurement rate by a factor of over 300 is discussed. It uses the delayed coincidence method, where a start photomultiplier tube (PMT) provides a signal synchronized to the excitation of the specimen and a stop PMT samples the resulting fluorescent lifetime spectrum. Typical

W. W. Moses

1992-01-01

203

SUNS-VOC AND MINORITY CARRIER LIFETIME MEASUREMENTS OF III-V TANDEM SOLAR CELLS  

E-print Network

SUNS-VOC AND MINORITY CARRIER LIFETIME MEASUREMENTS OF III-V TANDEM SOLAR CELLS Bhumika Chhabra to determine the minority carrier lifetime, saturation current and surface recombination velocity transient or quasi-steady state) and examination of the open circuit voltage with light intensity

Honsberg, Christiana

204

New Measurement of the Cosmic-Ray Positron Fraction from 5 to 15 GeV  

E-print Network

We present a new measurement of the cosmic-ray positron fraction at energies between 5 and 15 GeV with the balloon-borne HEAT-pbar instrument in the spring of 2000. The data presented here are compatible with our previous measurements, obtained with a different instrument. The combined data from the three HEAT flights indicate a small positron flux of non-standard origin above 5 GeV. We compare the new measurement with earlier data obtained with the HEAT-e+- instrument, during the opposite epoch of the solar cycle, and conclude that our measurements do not support predictions of charge sign dependent solar modulation of the positron abundance at 5 GeV.

J. J. Beatty; A. Bhattacharyya; C. Bower; S. Coutu; M. A. DuVernois; S. McKee; S. A. Minnick; D. Muller; J. Musser; S. Nutter; A. W. Labrador; M. Schubnell; S. Swordy; G. Tarle; A. Tomasch

2004-12-09

205

Radiation damage and electron lifetime measurements for liquid ionization chambers  

Microsoft Academic Search

Ionization chambers filled with liquids at room temperature have begun to be implemented in high-energy physics for total-ionization calorimeters and offer potential applications in medical physics for dosimetry and imaging of radiotherapy beams. One liquid that is commonly used is 2,2,4,4 tetramethyl pentane (TMP). When suitably purified, the lifetime of electrons in this liquid can be on the order of

M. J. Longo; L. E. Antonuk; L. H. Oesch; C. F. Wild

1990-01-01

206

Forward angle scattering effects in the measurement of total cross sections for positron scattering  

NASA Astrophysics Data System (ADS)

Measurements of total scattering by positron impact have typically excluded a significant portion of the forward scattering angles of the differential cross section. This paper demonstrates the effect that this can have on measurements of the total cross section. We show that much of the apparent disagreement between experimental measurements of positron scattering from atoms and molecules may be explained by this excluded angular range. It is shown that this same effect may also lead to an anomalous energy dependence of some cross sections.

Sullivan, J. P.; Makochekanwa, C.; Jones, A.; Caradonna, P.; Slaughter, D. S.; Machacek, J.; McEachran, R. P.; Mueller, D. W.; Buckman, S. J.

2011-02-01

207

Measuring and Sorting Cell Populations Expressing Isospectral Fluorescent Proteins with Different Fluorescence Lifetimes  

PubMed Central

Study of signal transduction in live cells benefits from the ability to visualize and quantify light emitted by fluorescent proteins (XFPs) fused to different signaling proteins. However, because cell signaling proteins are often present in small numbers, and because the XFPs themselves are poor fluorophores, the amount of emitted light, and the observable signal in these studies, is often small. An XFP's fluorescence lifetime contains additional information about the immediate environment of the fluorophore that can augment the information from its weak light signal. Here, we constructed and expressed in Saccharomyces cerevisiae variants of Teal Fluorescent Protein (TFP) and Citrine that were isospectral but had shorter fluorescence lifetimes, ?1.5 ns vs ?3 ns. We modified microscopic and flow cytometric instruments to measure fluorescence lifetimes in live cells. We developed digital hardware and a measure of lifetime called a “pseudophasor” that we could compute quickly enough to permit sorting by lifetime in flow. We used these abilities to sort mixtures of cells expressing TFP and the short-lifetime TFP variant into subpopulations that were respectively 97% and 94% pure. This work demonstrates the feasibility of using information about fluorescence lifetime to help quantify cell signaling in living cells at the high throughput provided by flow cytometry. Moreover, it demonstrates the feasibility of isolating and recovering subpopulations of cells with different XFP lifetimes for subsequent experimentation. PMID:25302964

Naivar, Mark; Houston, Jessica P.; Brent, Roger

2014-01-01

208

Electron Beam Polarization Measurement Using Touschek Lifetime Technique  

SciTech Connect

Electron beam loss due to intra-beam scattering, the Touschek effect, in a storage ring depends on the electron beam polarization. The polarization of an electron beam can be determined from the difference in the Touschek lifetime compared with an unpolarized beam. In this paper, we report on a systematic experimental procedure recently developed at Duke FEL laboratory to study the radiative polarization of a stored electron beam. Using this technique, we have successfully observed the radiative polarization build-up of an electron beam in the Duke storage ring, and determined the equilibrium degree of polarization and the time constant of the polarization build-up process.

Sun, Changchun; /Duke U., DFELL; Li, Jingyi; /Duke U., DFELL; Mikhailov, Stepan; /Duke U., DFELL; Popov, Victor; /Duke U., DFELL; Wu, Wenzhong; /Duke U., DFELL; Wu, Ying; /Duke U., DFELL; Chao, Alex; /SLAC; Xu, Hong-liang; /Hefei, NSRL; Zhang, Jian-feng; /Hefei, NSRL

2012-08-24

209

A New Measurement of the Muon Lifetime and the Determination of the Fermi Coupling Constant  

NASA Astrophysics Data System (ADS)

A new measurement of the muon lifetime, ??, at the 11 ppm level will be reported. This is the first result from the MuLan experiment, which is pursuing the ambitious goal of a 1 ppm determination of the muon lifetime---a 20-fold improvement. The experiment is motivated by recent theoretical improvements in extracting the Fermi coupling constant GF, from the measured lifetime; the theoretical uncertainty is now less than 1 ppm. The coupling constant GF is an essential parameter of the standard model and represents the strength of the weak interaction. Progress, highlights and future plans for this experiment will also be discussed.

Giovanetti, Kevin

2007-04-01

210

Measurement of the lifetime of the Bc+/- meson in the semileptonic decay channel.  

PubMed

Using approximately 1.3 fb(-1) of data collected by the D0 detector between 2002 and 2006, we measure the lifetime of the Bc+/- meson in the Bc-/+-->J/psimicro+/-+X final state. A simultaneous unbinned likelihood fit to the J/psi+micro invariant mass and lifetime distributions yields a signal of 881+/-80(stat) candidates and a lifetime measurement of tau(Bc+/-)=0.448(-0.036)(+0.038)(stat)+/-0.032(syst) ps. PMID:19392512

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Avila, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Kalk, J M; Karmanov, D; Kasper, P A; Katsanos, I; Kau, D; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Krop, D; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, W M; Leflat, A; Lellouch, J; Leveque, J; Li, J; Li, L; Li, Q Z; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna, R; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Millet, T; Mitrevski, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rich, P; Rieger, J; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G

2009-03-01

211

Photoluminescence spectroscopy and lifetime measurements from self-assembled semiconductor-metal nanoparticle hybrid arrays.  

SciTech Connect

We present results of photoluminescence spectroscopy and lifetime measurements on thin film hybrid arrays of semiconductor quantum dots and metal nanoparticles embedded in a block copolymer template. The intensity of emission as well as the measured lifetime would be controlled by varying the volume fraction and location of gold nanoparticles in the matrix. We demonstrate the ability to both enhance and quench the luminescence in the hybrids as compared to the quantum dot array films while simultaneously engineering large reduction in luminescence lifetime with incorporation of gold nanoparticles.

Haridas, M.; Basue, J. K.; Gosztola, D. J.; Wiederrecht, G. P. (Center for Nanoscale Materials); (Indian Inst. of Science)

2010-08-23

212

Measurement of the Bs(0) ? Ds-Ds+ and Bs(0) ? D-Ds+ effective lifetimes.  

PubMed

The first measurement of the effective lifetime of the B(s)(0) meson in the decay B(s)(0) ? Ds-Ds+ is reported using a proton-proton collision data set, corresponding to an integrated luminosity of 3 fb(-1), collected by the LHCb experiment. The measured value of the B(s)(0) ? Ds-Ds+ effective lifetime is 1.379 ± 0.026 ± 0.017 ps, where the uncertainties are statistical and systematic, respectively. This lifetime translates into a measurement of the decay width of the light B(s)(0) mass eigenstate of ?L = 0.725 ± 0.014 ± 0.009 ps(-1). The B(s)(0) lifetime is also measured using the flavor-specific B(s)(0)? D-Ds+ decay to be 1.52 ± 0.15 ± 0.01 ps. PMID:24702350

Aaij, R; Adeva, B; Adinolfi, M; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Andreotti, M; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Badalov, A; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Batozskaya, V; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Borsato, M; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Calabrese, R; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Cheung, S-F; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D C; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Dalseno, J; David, P; David, P N Y; Davis, A; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Donleavy, S; Dordei, F; Dorosz, P; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Falabella, A; Färber, C; Farinelli, C; Farry, S; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fiorini, M; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianelle, A; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grillo, L; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Hafkenscheid, T W; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hoballah, M; Hombach, C; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Kenyon, I R; Ketel, T; Khanji, B; Klaver, S; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kurek, K; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Liles, M; Lindner, R; Linn, C; Lionetto, F; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lowdon, P; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Luppi, E; Lupton, O; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Maratas, J; Marconi, U; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Martynov, A; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Mazurov, A; McCann, M; McCarthy, J; McNab, A; McNulty, R; McSkelly, B; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morandin, M; Morawski, P

2014-03-21

213

Spectroscopy and lifetime measurements in 66Ge,69Se, and 65Ga using fragmentation reactions  

NASA Astrophysics Data System (ADS)

Lifetimes of low-lying excited states have been measured in 66Ge,69Se, and 65Ga using a ? -ray lineshape method. The results confirm the previously reported 71- state lifetime in 66Ge. The lifetime of the yrast 5 /2- state in 65Ga is measured for the first time. Lifetime measurements of two excited 3 /2- states in 69Se are also reported. Two previously unobserved ? rays have been identified in 69Se. ? -? coincidence measurements have been used to place one of these in the level scheme. 69Se excited state populations are compared to shell-model calculations using the GXPF1A interaction in the fp model space. Theoretical spectroscopic factors to excited states in 69Se have identified three candidate levels for the origin of one of the new transitions.

Nichols, A. J.; Wadsworth, R.; Bentley, M. A.; Davies, P. J.; Henderson, J.; Jenkins, D. G.; Paterson, I.; Iwasaki, H.; Lemasson, A.; Bader, V. M.; Baugher, T.; Bazin, D.; Berryman, J. S.; Gade, A.; Morse, C.; Stroberg, S. R.; Weisshaar, D.; Whitmore, K.; Wimmer, K.; de Angelis, G.; Dewald, A.; Braunroth, T.; Fransen, C.; Hackstein, M.; Miller, D.

2015-01-01

214

Measurement of the ?[superscript 0 over subscript b] lifetime and mass in the ATLAS experiment  

E-print Network

A measurement of the ?[superscript 0 over subscript b] lifetime and mass in the decay channel ?[superscript 0 over subscript b]?J/?(?[superscript +]?[superscript -])?[superscript 0](p?[superscript -]) is presented. The ...

Taylor, Frank E.

215

Lifetime measurements of high-lying short lived states in {sup 69}As  

SciTech Connect

Lifetimes of high-spin states in {sup 69}As have been measured using Doppler shift attenuation technique with the GASP and RFD setup. The determined transition probabilities indicate large deformation associated with some rotational bands in this nucleus.

Matejska-Minda, M.; Bednarczyk, P.; Fornal, B.; Ciemala, M.; Kmiecik, M.; Krzysiek, M.; Maj, A.; Meczynski, W.; Myalski, S.; Styczen, J.; Zieblinski, M.; Angelis, G. de; Huyuk, T.; Michelagnoli, C.; Sahin, E.; Aydin, S.; Farnea, E.; Menegazzo, R.; Recchia, F.; Ur, C. A. [Institute of Nuclear Physics, Polish Academy of Sciences, Krakow (Poland); INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy); Dipartimento di Fisica e INFN Padova (Italy); Dipartimento di Fisica e INFN Milano (Italy); Heavy Ion Laboratory, University of Warsaw (Poland); University of York (United Kingdom); and others

2012-10-20

216

Lifetime measurements in an electrostatic ion beam trap using image charge monitoring  

SciTech Connect

A technique for mass-selective lifetime measurements of keV ions in a linear electrostatic ion beam trap is presented. The technique is based on bunching the ions using a weak RF potential and non-destructive ion detection by a pick-up electrode. This method has no mass-limitation, possesses the advantage of inherent mass-selectivity, and offers a possibility of measuring simultaneously the lifetimes of different ion species with no need for prior mass-selection.

Rahinov, Igor; Toker, Yoni; Heber, Oded; Rappaport, Michael; Zajfman, Daniel [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Strasser, Daniel [Institute of Chemistry, Hebrew University of Jerusalem, 91904 Jerusalem (Israel); Schwalm, Dirk [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Max Planck Institute for Nuclear Physics, D-69117 Heidelberg (Germany)

2012-03-15

217

Location and size of nanoscale free-volume holes in crosslinked- polytetrafluoroethylene-based graft-type polymer electrolyte membranes determined by positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

The location and size of nanoscale free-volume holes (nanoholes) in graft-type polymer electrolyte membranes (PEMs), which were prepared by radiation-induced graft polymerization (grafting) of styrene into crosslinked-polytetrafluoroethylene (cPTFE) films and subsequent sulfonation, were investigated using positron annihilation lifetime (PAL) spectroscopy. The PAL spectra of the PEMs indicated the existence of two types of ortho-positronium (o-Ps) species, corresponding to nanoholes with volumes of 0.11 and 0.38 nm3. A comparison of the PAL data of the PEMs with that of the precursor original cPTFE and polystyrene-grafted films demonstrated the probability that the smaller holes were located in both the PTFE crystalline phases and the poly(styrene sulfonic acid) graft regions, whereas the larger holes are potentially localized in the PTFE amorphous phases. Taking into account both the size and the location of the nanoholes, it was concluded that gas transport through the larger holes in the amorphous PTFE phases was dominant over permeation through the smaller holes in the PTFE crystals and grafted regions.

Sawada, Shin-ichi; Yabuuchi, Atsushi; Maekawa, Masaki; Kawasuso, Atsuo; Maekawa, Yasunari

2013-06-01

218

Microstructure of Celluloses Studied by Positron Annihilation  

NASA Astrophysics Data System (ADS)

Positron Annihilation Lifetime (PAL) measurements have been performed on Avicel and Whatman celluloses and their ball-milled derivatives as well as cellulose acetates. Correlations between crystallinity and fractional microsctructures found. Combined studies using PAL and FTIR on deuterated celluloses and moisture sorptions will be presented.

Cao, Huimin; Lou, Yongming; Jean, Renwu; Pekarovicova, Y. C.; Venditti, Alexandra

1997-03-01

219

Measurement of the Lambda b lifetime in the exclusive decay Lambda b --> J/psi Lambda.  

PubMed

We have measured the Lambda b lifetime using the exclusive decay Lambda b --> J/psi Lambda, based on 1.2 fb(-1) of data collected with the D0 detector during 2002-2006. From 171 reconstructed Lambda b decays, where the J/psi and Lambda are identified via the decays J/psi --> mu+ mu- and Lambda --> ppi, we measured the Lambda b lifetime to be tau(Lambda b)=1.218 (+0.130)/(-0.115) (stat) +/- 0.042(syst) ps. We also measured the B0 lifetime in the decay B0 --> J/psi(mu+ mu-)K(0)/(S)(pi+ pi-) to be tau(B0)=1.501 (+0.078)/(-0.074) (stat) +/- 0.050(syst) ps, yielding a lifetime ratio of tau(Lambda b)/tau(B0)=0.811 (+0.096)/(-0.087) (stat) +/- 0.034(syst). PMID:17930660

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Jesus, A C S Assis; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Biscarat, C; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Gelé, D; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J M; Kalk, J R; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kothari, B; Kozelov, A V; Krop, D; Kryemadhi, A; Kuhl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lam, D; Lammers, S; Landsberg, G; Lazoflores, J; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lellouch, J; Lesne, V; Leveque, J; Lewis, P; Li, J; Li, L; Li, Q Z; Lietti, S M; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martin, B; McCarthy, R; Melnitchouk, A; Mendes, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Millet, T; Mitrevski, J; Molina, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; O'dell, V; O'neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osta, J; Otec, R; Otero Y Garzón, G J; Owen, M; Padley, P; Pangilinan, M; Panikashvili, N; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y

2007-10-01

220

The multi-scattering model for calculations of positron spatial distribution in the multilayer stacks, useful for conventional positron measurements  

SciTech Connect

The spatial distribution of positrons emitted from radioactive isotopes into stacks or layered samples is a subject of the presented report. It was found that Monte Carlo (MC) simulations using GEANT4 code are not able to describe correctly the experimental data of the positron fractions in stacks. The mathematical model was proposed for calculations of the implantation profile or positron fractions in separated layers or foils being components of a stack. The model takes into account only two processes, i.e., the positron absorption and backscattering at interfaces. The mathematical formulas were applied in the computer program called LYS-1 (layers profile analysis). The theoretical predictions of the model were in the good agreement with the results of the MC simulations for the semi infinite sample. The experimental verifications of the model were performed on the symmetrical and non-symmetrical stacks of different foils. The good agreement between the experimental and calculated fractions of positrons in components of a stack was achieved. Also the experimental implantation profile obtained using the depth scanning of positron implantation technique is very well described by the theoretical profile obtained within the proposed model. The LYS-1 program allows us also to calculate the fraction of positrons which annihilate in the source, which can be useful in the positron spectroscopy.

Dryzek, Jerzy [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland) [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland); Institute of Physics, Opole University, ul. Oleska 48, 45-052 Opole (Poland); Siemek, Krzysztof [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland)] [Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków (Poland)

2013-08-21

221

Measurement of the Positron Annihilation Induced Auger Electron Spectrum from Ag(100)  

NASA Astrophysics Data System (ADS)

Research has demonstrated that Positron Annihilation Induced Auger Spectroscopy (PAES) can be used to probe the top-most atomic layer of surfaces and to obtain Auger spectra that are completely free of beam-impact induced secondary background. The high degree of surface selectivity in PAES is a result of the fact that positrons implanted at low energies are trapped with high efficiency at an image-correlation potential well at the surface resulting in almost all of the positrons annihilating with atoms in the top-most layer. Secondary electrons associated with the impact of the incident positrons can be eliminated by a suitable choice of an incident beam energy. In this paper we present the results of measurements of the energy spectrum of electrons emitted as a result of positron annihilation induced Auger electron emission from a clean Ag(100) surface using a series of incident beam energies ranging from 20 eV down to 2 eV. A peak in the spectrum was observed at ~40 eV corresponding to the N2,3VV Auger transition in agreement with previous PAES studies. This peak was accompanied by an even larger low energy tail which persisted even at the lowest beam energies. Our results for Ag(100) are consistent with previous studies of Cu and Au and indicate that a significant fraction of electrons leaving the sample are emitted in the low energy tail and suggest a strong mechanism for energy sharing in the Auger process.

Joglekar, P.; Shastry, K.; Fazleev, N. G.; Weiss, A. H.

2013-06-01

222

Frequency domain fluorescence lifetime microwell-plate platform for respirometry measurements  

NASA Astrophysics Data System (ADS)

Traditionally micro-well plate based platforms used in biology utilize fluorescence intensity based methods to measure processes of biological relevance. However, fluorescence intensity measurements suffer from calibration drift due to a variety of factors. Photobleaching and self-quenching of the fluorescent dyes cause the intensity signal to drop over the lifetime of sensor immobilized inside the well. Variation in turbidity of the sample during the course of the measurement affects the measured fluorescence intensity. In comparison, fluorescence lifetime measurements are not significantly affected by these factors because fluorescence lifetime is a physico-chemical property of the fluorescent dye. Reliable and inexpensive frequency domain fluorescence lifetime instrumentation platforms are possible because the greater tolerance for optical alignment, and because they can be performed using inexpensive light sources such as LEDs. In this paper we report the development of a frequency domain fluorescence lifetime well-plate platform utilizing an oxygen sensitive transition-metal ligand complex fluorophore with a lifetime in the microsecond range. The fluorescence lifetime dye is incorporated in a polymer matrix and immobilized on the base of micro-well of a 60 well micro-well plate. Respiration measurements are performed in both aqueous and non-aqueous environment. Respirometry measurements were recorded from single Daphnia magna egg in hard water. Daphnia is an aquatic organism, important in environmental toxicology as a standard bioassay and early warning indicator for water quality monitoring. Also respirometry measurements were recorded from Tribolium castaneum eggs, which are common pests in the processed flour industry. These eggs were subjected to mitochondrial electron transport chain inhibitor such as potassium cyanide (KCN) and its effects on egg respiration were measured in real-time.

Chatni, M. R.; Yale, G.; Van Ryckeghem, A.; Porterfield, D. M.

2010-04-01

223

Measurement of separate cosmic-ray electron and positron spectra with the fermi large area telescope.  

PubMed

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting Earth's shadow, which is offset in opposite directions for opposite charges due to Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy. PMID:22304252

Ackermann, M; Ajello, M; Allafort, A; Atwood, W B; Baldini, L; Barbiellini, G; Bastieri, D; Bechtol, K; Bellazzini, R; Berenji, B; Blandford, R D; Bloom, E D; Bonamente, E; Borgland, A W; Bouvier, A; Bregeon, J; Brigida, M; Bruel, P; Buehler, R; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Cecchi, C; Charles, E; Chekhtman, A; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Conrad, J; Cutini, S; de Angelis, A; de Palma, F; Dermer, C D; Digel, S W; do Couto E Silva, E; Drell, P S; Drlica-Wagner, A; Favuzzi, C; Fegan, S J; Ferrara, E C; Focke, W B; Fortin, P; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Germani, S; Giglietto, N; Giommi, P; Giordano, F; Giroletti, M; Glanzman, T; Godfrey, G; Grenier, I A; Grove, J E; Guiriec, S; Gustafsson, M; Hadasch, D; Harding, A K; Hayashida, M; Hughes, R E; Jóhannesson, G; Johnson, A S; Kamae, T; Katagiri, H; Kataoka, J; Knödlseder, J; Kuss, M; Lande, J; Latronico, L; Lemoine-Goumard, M; Llena Garde, M; Longo, F; Loparco, F; Lovellette, M N; Lubrano, P; Madejski, G M; Mazziotta, M N; McEnery, J E; Michelson, P F; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nakamori, T; Nolan, P L; Norris, J P; Nuss, E; Ohno, M; Ohsugi, T; Okumura, A; Omodei, N; Orlando, E; Ormes, J F; Ozaki, M; Paneque, D; Parent, D; Pesce-Rollins, M; Pierbattista, M; Piron, F; Pivato, G; Porter, T A; Rainò, S; Rando, R; Razzano, M; Razzaque, S; Reimer, A; Reimer, O; Reposeur, T; Ritz, S; Romani, R W; Roth, M; Sadrozinski, H F-W; Sbarra, C; Schalk, T L; Sgrò, C; Siskind, E J; Spandre, G; Spinelli, P; Strong, A W; Takahashi, H; Takahashi, T; Tanaka, T; Thayer, J G; Thayer, J B; Tibaldo, L; Tinivella, M; Torres, D F; Tosti, G; Troja, E; Uchiyama, Y; Usher, T L; Vandenbroucke, J; Vasileiou, V; Vianello, G; Vitale, V; Waite, A P; Winer, B L; Wood, K S; Wood, M; Yang, Z; Zimmer, S

2012-01-01

224

Measurement of Separate Cosmic-Ray Electron and Positron Spectra with the Fermi Large Area Telescope  

NASA Technical Reports Server (NTRS)

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting the Earth's shadow, which is offset in opposite directions for opposite charges due to the Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 GeV and 200 GeV, We confirm that the fraction rises with energy in the 20-100 GeV range and determine for the first time that it continues to rise between 100 and 200 GeV,

Ackermann, M.; Ajello, M.; Allafort, A.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Brogland, A. W.; Bouvier, A.; Bregeon, J.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Ferrara, E. C.; Harding, A. K.; McEnery, J. E.

2011-01-01

225

Measurement of Separate Cosmic-Ray Electron and Positron Spectra with the Fermi Large Area Telescope  

NASA Technical Reports Server (NTRS)

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting Earth's shadow, which, is offset in opposite directions for opposite charges due to Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 and 200 Ge V. We confirm that the fraction rises with energy in the 20-100 Ge V range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy.

Ferrara, E. C.; Harding, A. K.; McEnery, J. E.; Moiseev, A. A.; Ackemann, M.

2012-01-01

226

Measurement of the Lifetimes of the Neutral and Charged D Mesons.  

NASA Astrophysics Data System (ADS)

Results are presented on the use of a high-resolution drift chamber in the Mark II Detector at PEP to measure the lifetimes of D('0) and D('(+OR-)) mesons produced in e('+)e('-) annihilations at 29 GeV. Based on a sample of 74 events for the D('0) mesons and 23 events for the D('(+OR-)) mesons, the lifetimes are found to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). The ratio of these lifetimes,. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). indicates that the decays of these mesons cannot be explained by the simple spectator model of charmed particle decay.

Gladney, Larry Donnie

1985-06-01

227

A portable time-domain LED fluorimeter for nanosecond fluorescence lifetime measurements  

SciTech Connect

Fluorescence lifetime measurements are becoming increasingly important in chemical and biological research. Time-domain lifetime measurements offer fluorescence multiplexing and improved handling of interferers compared with the frequency-domain technique. In this paper, an all solid-state, filterless, and highly portable light-emitting-diode based time-domain fluorimeter (LED TDF) is reported for the measurement of nanosecond fluorescence lifetimes. LED based excitation provides more wavelengths options compared to laser diode based excitation, but the excitation is less effective due to the uncollimated beam, less optical power, and longer latency in state transition. Pulse triggering and pre-bias techniques were implemented in our LED TDF to improve the peak optical power to over 100 mW. The proposed pulsing circuit achieved an excitation light fall time of less than 2 ns. Electrical resetting technique realized a time-gated photo-detector to remove the interference of the excitation light with fluorescence. These techniques allow the LED fluorimeter to accurately measure the fluorescence lifetime of fluorescein down to concentration of 0.5 ?M. In addition, all filters required in traditional instruments are eliminated for the non-attenuated excitation/emission light power. These achievements make the reported device attractive to biochemical laboratories seeking for highly portable lifetime detection devices for developing sensors based on fluorescence lifetime changes. The device was initially validated by measuring the lifetimes of three commercial fluorophores and comparing them with reported lifetime data. It was subsequently used to characterize a ZnSe quantum dot based DNA sensor.

Wang, Hongtao; Salthouse, Christopher D., E-mail: salthouse@ecs.umass.edu [Electrical and Computer Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Qi, Ying; Mountziaris, T. J. [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States) [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Chemical Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States)

2014-05-15

228

Functional magnetic resonance imaging (fMRI) and positron emission tomography measure local changes in brain  

E-print Network

202 Functional magnetic resonance imaging (fMRI) and positron emission tomography measure local underlying the different signal modalities. Address Massachusetts General Hospital Nuclear Magnetic Resonance dipole EEG electroencephalography ERP event-related potential fMRI functional magnetic resonance imaging

Udgaonkar, Jayant B.

229

Measurements of total cross sections for positrons and electrons colliding with atomic hydrogen  

Microsoft Academic Search

We have made preliminary measurements of total cross sections for 30 to 300 eV positrons and electrons scattered by atomic and molecular hydrogen using a beam-transmission technique. The atomic hydrogen is obtained from an rf discharge source, and recombination in our aluminium scattering cell is minimized by maintaining the cell at about 150 K. Relative total cross sections are obtained

S. Zhou; W. E. Kauppila; C. K. Kwan; T. S. Stein

1993-01-01

230

Brain dopamine metabolism in patients with Parkinson's disease measured with positron emission tomography  

Microsoft Academic Search

L-[18F] fluorodopa was administered in trace amounts intravenously to healthy control subjects and to patients with Parkinson's disease. Striatal uptake of radioactivity was measured using positron emission tomography. The capacity of the striatum to retain tracer was severely impaired in patients compared to controls. This may reflect a reduction of striatal dopamine storage in Parkinson's disease. Patients showing the \\

K L Leenders; A J Palmer; N Quinn; J C Clark; G Firnau; E S Garnett; C Nahmias; T Jones; C D Marsden

1986-01-01

231

Simulation free measurement of the B+ lifetime using decays selected using displaced tracks  

SciTech Connect

The lifetime of the B{sup {+-}} meson is measured using the decay channel B{sup +} {yields} {bar D}{sup 0}{pi}{sup +}. The measurement is made using approximately 1.0 fb{sup -1} of Tevatron proton-anti-proton collision data at {radical}s = 1.96 TeV collected by the CDF detector. The data were collected using impact parameter based triggers that were designed to select events with a secondary vertex. The trigger selection criteria result in data rich in a variety of B hadron decays, but intrinsically bias the lifetime distribution of the collected signal events. The traditional way to compensate for the bias is to use information from simulation. Presented here is a new method for correction of the lifetime bias using an analytical technique that uses information from the data only. This eliminates measurement uncertainty due to data and simulation agreement, ultimately resulting in a smaller systematic measurement uncertainty. The B{sup {+-}} lifetime measurement is the first measurement using this new technique and demonstrates its potential for use in future measurements. The B{sup {+-}} lifetime is measured to be {tau}(B{sup {+-}}) = 1.662 {+-} 0.023(stat) {+-} 0.015(syst)ps.

Malde, Sneha; /Oxford U.

2009-03-01

232

Laser measurements of the radiative lifetime of the B state of CN  

NASA Technical Reports Server (NTRS)

A turnable dye laser was used to measure the radiative lifetime of the individual rotational levels of the B2 Sigma (+) state of CN. The radiative lifetime of the unperturbed rotational levels is 65.6 plus or minus 1.0 nsec. A longer radiative lifetime of 72 plus or minus 1 nsec is observed for the Kaon prime = 4 level of the B state. The measured values of the perturbed and unperturbed levels support the longer lifetimes for the A2 meson pion state of CN. The quenching cross section of the B2 Sigma state of CN is 41 plus or minus 20 Angstroms squared and is independent of the rotational energy of the B state.

Jackson, W. M.

1974-01-01

233

Advanced lifetime PSP imaging system for pressure and temperature field measurement  

NASA Astrophysics Data System (ADS)

The newly designed lifetime imaging system (LIS), which was composed of a multi-gated CCD camera and LED illuminators, has been developed to measure simultaneously pressure and temperature field from luminescent lifetime decay of pressure-sensitive paint (PSP). The new system could reduce the measurement error due to shot noise of a CCD and laser speckle, compared to the previous lifetime imaging system. Optimization of PSP film thickness on white basecoat was also conducted for improving measurement accuracy, and could minimize the measurement error. As a verification test, pressure and temperature images on a simple delta wing were visualized by the newly designed LIS. The quality of the pressure image was considerably improved in comparison with that measured by the previous system. These results indicated that the new LIS was a practical measurement tool to acquire simultaneously pressure and temperature field on an aerodynamic model surface.

Mitsuo, Kazunori; Asai, Keisuke; Takahashi, Akira; Mizushima, Hiroshi

2006-06-01

234

First working group meeting on the minority carrier diffusion length/lifetime measurement: Results of the round robin lifetime/diffusion length tests  

SciTech Connect

As was noted in the cover letter that accompanied the samples, the eleven bare silicon samples were from various manufacturers. Table I lists the codes for the samples and the manufacturer of each sample. It also notes if the sample was single or poly-crystalline. The samples had been polished on one side before being sent out for measurements, but no further processing was done. The participants of the study were asked to measure either the lifetime or diffusion length of each of the samples using their standard procedure. Table II shows the experimental conditions used by the groups who measured diffusion length. All the diffusion length measurements were performed using the Surface Photovoltage method (SPV). Table M shows the experimental conditions for the lifetime measurements. All the lifetime measurements were made using the Photoconductance Decay method (PCD) under low level injection. These tables show the diameter of the spot size used during the measurement (the effective sampling area), the locations where measurements were taken, and the number of measurements taken at each location. Table N shows the results of the measurements. The table is divided into diffusion length and lifetime measurements for each sample. The values listed are the average values reported by each group. One of the immediate artifacts seen in the data is the large variation in the lifetime measurements. The values from MIT and Mobil are generally close. However, the measurements from NCSU are typically an order of magnitude lower.

Cudzinovic, M.; Sopori, B. [comp.] [comp.

1995-11-01

235

Lifetime measurement of the 8s level in francium L. A. Orozco,2  

E-print Network

Lifetime measurement of the 8s level in francium E. Gomez,1 L. A. Orozco,2 A. Perez Galvan,2 and G of the 8s level lifetime of francium, the heaviest of alkali-metal atoms. Fr is yet to be used in parity the possibility of a PNC experiment in a chain of francium isotopes. We use the method of time-correlated single

Orozco, Luis A.

236

Measurement of the 7p²Pââ Level Lifetime in Atomic Francium  

Microsoft Academic Search

We present the first measurement of an atomic radiative lifetime in Fr. We use a time-correlated single photon counting technique with a cold sample of ²¹°Fr atoms in a magneto-optic trap. The results are a precision experimental test of the atomic many-body perturbation theory applied to the heaviest alkali. The lifetime for the 7p ²Pââ level of 21.02(16) ns gives

W. Z. Zhao; J. E. Simsarian; L. A. Orozco; W. Shi; G. D. Sprouse

1997-01-01

237

Cascade Problems in Some Atomic Lifetime Measurements at a Heavy-Ion Storage Ring  

SciTech Connect

Lifetimes of 3s{sup 2}3p{sup k} ground configuration levels of Al-, Si-, P-, and S-like ions of Be, Co, and Ni have been measured at a heavy-ion storage ring. Some of the observed decay curves show strong evidence of cascade repopulation from specific 3d levels that feature lifetimes in the same multi-millisecond range as the levels of the ground configuration.

Trabert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

2008-10-09

238

Lifetime measurement and calibration from pressure-sensitive paint luminescence images  

Microsoft Academic Search

A dual-image lifetime technique for acquiring surface pressure measurements from pressure-sensitive paint image data has been developed. This technique eliminates the need to acquire a ``wind-off'' reference image as required by the traditional radiometric technique, which is known to corrupt results. Here a luminescence lifetime-versus-pressure calibration experiment was conducted. Uncertainty was nominally less than +\\/-4% and decreased as signal level

T. F. Drouillard; M. A. Linne; L. P. Goss; J. R. Gord; G. J. Fiechtner

2003-01-01

239

Transcutaneous measurement of the arterial input function in positron emission tomography  

SciTech Connect

Positron emission tomography (PET) provides a powerful tool in medical research. Biochemical function can be both precisely localized and quantitatively measured. To achieve reliable quantitation it is necessary to know the time course of activity concentration in the arterial blood during the measurement. In this study the arterial blood curve from the brachial artery is compared to the activity measured in the internal carotid artery with a new transcutaneous detector.

Litton, J.E.; Eriksson, L. (Dept. of Clinical Neurophysiology, Dept. of Neuroradiology and Dept. of Psychiatry and Psychology, Karolinska Hospital , S-104 01 Stockholm (SE))

1990-04-01

240

Carrier Lifetime Measurement for Characterization of Ultraclean Thin p/p+ Silicon Epitaxial Layers  

NASA Astrophysics Data System (ADS)

Carrier lifetime is one of the few parameters which can give information about the low defect densities in today's semiconductors. In principle there is no lower limit to the defect density determined by lifetime measurements. No other technique can easily detect defect densities as low as 10 -9 - 10-10 cm-3 in a simple, contactless room temperature measurement. However in practice, recombination lifetime ? r measurements such as photoconductance decay (PCD) and surface photovoltage (SPV) that are widely used for characterization of bulk wafers face serious limitations when applied to thin epitaxial layers, where the layer thickness is smaller than the minority carrier diffusion length Ln. Other methods such as microwave photoconductance decay (µ-PCD), photoluminescence (PL), and frequency-dependent SPV, where the generated excess carriers are confined to the epitaxial layer width by using short excitation wavelengths, require complicated configuration and extensive surface passivation processes that make them time-consuming and not suitable for process screening purposes. Generation lifetime ?g, typically measured with pulsed MOS capacitors (MOS-C) as test structures, has been shown to be an eminently suitable technique for characterization of thin epitaxial layers. It is for these reasons that the IC community, largely concerned with unipolar MOS devices, uses lifetime measurements as a "process cleanliness monitor." However when dealing with ultraclean epitaxial wafers, the classic MOS-C technique measures an effective generation lifetime ?geff which is dominated by the surface generation and hence cannot be used for screening impurity densities. I have developed a modified pulsed MOS technique for measuring generation lifetime in ultraclean thin p/p+ epitaxial layers which can be used to detect metallic impurities with densities as low as 10-10 cm-3. The widely used classic version has been shown to be unable to effectively detect such low impurity densities due to the domination of surface generation; whereas, the modified version can be used suitably as a metallic impurity density monitoring tool for such cases.

Elhami Khorasani, Arash

241

Microstructural characterization of thin polymer films using Langley low energy positron flux generator  

NASA Technical Reports Server (NTRS)

We have developed a highly efficient scheme for generating high fluxes of slow positrons. These positrons have been successfully used to measure lifetimes in thin test films. The lifetime data have been used to develop two structure-property models for the test films. The first model relates the free volume cell size to the molecular weight of the polymer repeat unit. The second model relates the free volume fraction to the dielectric constant of the polymer film.

Singh, Jag. J.

1992-01-01

242

Two-dimensional analysis of positron age-momentum correlation (AMOC) data  

Microsoft Academic Search

By measuring the individual positron lifetimes (= positron ages) together with the energies of one of the annihilation quanta in a triple-coincidence set-up (age-momentum correlation, AMOC), time-resolved information on the evolution of the positron states may be obtained. The present paper describes a data evaluation procedure that makes full use of the time-resolved information provided by the AMOC relief (number

A. Siegle; H. Stoll; P. Castellaz; J. Major; H. Schneider; A. Seeger

1997-01-01

243

A new way of using positron-lifetime measurements to study lattice defects  

E-print Network

the properties of vacancies in metals in thermal equilibrium. The many experimental results that have been the source isotope (commonly 22Na in the form of sodium chloride) either directly on a surface, or between thin organic (or metallic) foils sandwiched between two plates of the material to be investigated

Boyer, Edmond

244

Measurement of the B¯s? meson lifetime in Ds??? decays.  

PubMed

We present a measurement of the ratio of the B¯s? meson lifetime, in the flavor-specific decay to Ds???, to that of the B¯? meson. The pp collision data used correspond to an integrated luminosity of 1??fb(-1), collected with the LHCb detector, at a center-of-mass energy of 7 TeV. Combining our measured value of 1.010±0.010±0.008 for this ratio with the known B¯? lifetime, we determine the flavor-specific B¯s? lifetime to be ?(B¯s? )=1.535±0.015±0.014??ps, where the uncertainties are statistical and systematic, respectively. This is the most precise measurement to date, and is consistent with previous measurements and theoretical predictions. PMID:25379914

Aaij, R; Adeva, B; Adinolfi, M; Affolder, A; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Anderson, J; Andreassen, R; Andreotti, M; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Badalov, A; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Batozskaya, V; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Borsato, M; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brodzicka, J; Brook, N H; Brown, H; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Calabrese, R; Calvi, M; Calvo Gomez, M; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Chefdeville, M; Chen, S; Cheung, S-F; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Corvo, M; Counts, I; Couturier, B; Cowan, G A; Craik, D C; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Dalseno, J; David, P; David, P N Y; Davis, A; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Donleavy, S; Dordei, F; Dorigo, M; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dreimanis, K; Dujany, G; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Ely, S; Esen, S; Evans, H-M; Evans, T; Falabella, A; Färber, C; Farinelli, C; Farley, N; Farry, S; Fay, R; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Fu, J; Furfaro, E; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; García Pardiñas, J; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gavardi, L; Gavrilov, G; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianelle, A; Giani', S; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gotti, C; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grillo, L; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Han, X; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Henry, L; Hernando Morata, J A; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hoballah, M; Hombach, C; Hulsbergen, W; Hunt, P; Hussain, N; Hutchcroft, D; Hynds, D; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jalocha, J; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Karodia, S; Kelsey, M; Kenyon, I R; Ketel, T; Khanji, B; Khurewathanakul, C; Klaver, S; Klimaszewski, K; Kochebina, O; Kolpin, M; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kurek, K; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanfranchi, G; Langenbruch, C; Langhans, B; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Likhomanenko, T; Liles, M; Lindner, R; Linn, C; Lionetto, F; Liu, B; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lowdon, P; Lu, H; Lucchesi, D; Luo, H; Lupato, A; Luppi, E; Lupton, O; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Malinin, A; Manca, G; Mancinelli, G; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M

2014-10-24

245

Precision Measurement of the Mass and Lifetime of the ?b- Baryon  

NASA Astrophysics Data System (ADS)

We report on measurements of the mass and lifetime of the ?b- baryon using about 1800 ?b- decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0 fb-1 collected by the LHCb experiment. The decays are reconstructed in the ?b-??c0?-, ?c0?p K-K-?+ channel and the mass and lifetime are measured using the ?b0??c+?- mode as a reference. We measure M (?b-)-M (?b0)=178.36 ±0.46 ±0.16 MeV /c2 , (??b-/??b0)=1.089 ±0.026 ±0.011 , where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the ?b- mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations.

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; Brett, D.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Brown, H.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Dean, C.-T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H.-M.; Evans, T.; Falabella, A.; Färber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, RF; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; García Pardiñas, J.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gavardi, L.; Geraci, A.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gian?, S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kelsey, M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.

2014-12-01

246

Measurement of the B¯s 0 Meson Lifetime in Ds+?- Decays  

NASA Astrophysics Data System (ADS)

We present a measurement of the ratio of the B¯s 0 meson lifetime, in the flavor-specific decay to Ds+?-, to that of the B¯ 0 meson. The p p collision data used correspond to an integrated luminosity of 1 fb-1 , collected with the LHCb detector, at a center-of-mass energy of 7 TeV. Combining our measured value of 1.010 ±0.010 ±0.008 for this ratio with the known B¯ 0 lifetime, we determine the flavor-specific B¯s 0 lifetime to be ? (B¯s 0)=1.535 ±0.015 ±0.014 ps , where the uncertainties are statistical and systematic, respectively. This is the most precise measurement to date, and is consistent with previous measurements and theoretical predictions.

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cassina, L.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H.-M.; Evans, T.; Falabella, A.; Färber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; García Pardiñas, J.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gaspar, C.; Gauld, R.; Gavardi, L.; Gavrilov, G.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Giani', S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kelsey, M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.

2014-10-01

247

Performance of the Beijing pulsed variable-energy positron beam  

NASA Astrophysics Data System (ADS)

In order to study the depth-dependent characteristics of open-volume defects in thin surface layers, the variable-energy positron lifetime spectroscopy (VEPLS) has been enabled by pulsing a continuous positron beam. The buncher is a quarter-wave coaxial resonator and the RF-signal is fed in by a coupling loop with a frequency of 149.89 MHz and the reflection factor of 0.05 measured by a Network Analyzer. Three synchronic signals with their phases and amplitudes adjusted independently are supplied for start signal of the positron lifetime measurement and the power signal by an electronic system. The stop signal is derived from a detector, a BaF 2 scintillator coupled to a photomultiplier-tube (Hamamatsu). The time resolution of 295 ps (FWHM) was achieved for a Kapton film and a Ti sample at positron energies in the range between 1 keV and 30 keV.

Wang, B. Y.; Ma, Y. Y.; Zhang, Z.; Yu, R. S.; Wang, P.

2008-10-01

248

A measurement of AFBb in lifetime tagged heavy flavour Z decays  

Microsoft Academic Search

A new measurement of the forward-backward asymmetry in Z--> bb decays is presented. Hadrons from b decays are tagged using their long lifetimes. The b quark charge and direction are reconstructed with a hemisphere charge algorithm. The asymmetry and reconstructed b hemisphere charge are measured in the 69 pb-1 of data collected by ALEPH during 1991, 1992 and 1993. They

Damir Buskulic; David William Casper; I. de Bonis; D. Decamp; P. Ghez; C. Goy; J.-P. Lees; M.-N. Minard; P. Odier; B. Pietrzyk; F. Ariztizabal; M. Chmeissani; J. M. Crespo; I. Efthymiopoulos; E. Fernandez; M. Fernandez-Bosman; V. Gaitan; Ll. Garrido; M. Martinez; T S Mattison; S. Orteu; A. Pacheco; C. Padilla; Fabrizio Palla; A. Pascual; J. A. Perlas; F. Teubert; D. Creanza; M. de Palma; A. Farilla; Giuseppe Iaselli; G. Maggi; N. Marinelli; S. Natali; S. Nuzzo; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; Y. Chai; D. Huang; X. Huang; J. Lin; T. Wang; Y. Xie; D. Xu; R. Xu; J. Zhang; L. Zhang; W. Zhao; G. Bonvicini; J. Boudreau; P. Comas; P. Coyle; H. Drevermann; A. Engelhardt; R. W. Forty; G. Ganis; C. Gay; M. Girone; R. Hagelberg; J. Harvey; R. Jacobsen; B. Jost; J. Knobloch; I. Lehraus; M. Maggi; C. Markou; P. Mato; H. Meinhard; A. Minten; R. Miquel; P. Palazzi; J. R. Pater; P. Perrodo; J.-F. Pusztaszeri; F. Ranjard; L. Rolandi; J. Rothberg; M. Saich; D. Schlatter; M. Schmelling; W. Tejessy; I. R. Tomalin; R. Veenhof; A. Venturi; H. Wachsmuth; S. Wasserbaech; W. Wiedenmann; T. Wildish; W. Witzeling; J. Wotschack; Z. Ajaltouni; M. Bardadin-Otwinowska; A. Barres; C. Boyer; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; J.-C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; F. Saadi; T. Fearnley; J. B. Hansen; J. D. Hansen; P. H. Hansen; S. D. Johnson; R. Møllerud; B. S. Nilsson; A. Kyriakis; E. Simopoulou; I. Siotis; A. Vayaki; K. Zachariadou; A. Blondel; G. Bonneaud; J. C. Brient; P. Bourdon; L. Passalacqua; A. Rougé; M. Rumpf; R. Tanaka; A. Valassi; M. Verderi; H. Videau; D. J. Candlin; M. I. Parsons; E. Veitch; E. Focardi; G. Parrini; M. Corden; M. Delfino; C. Georgiopoulos; D. E. Jaffe; D. Levinthal; A. Antonelli; G. Nencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; F. Cerutti; V. Chiarella; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; M. Pepe-Altarelli; S. Salomone; P. Colrain; I. Ten Have; I. G. Knowles; J. G. Lynch; W. Maitland; W. T. Morton; C. Raine; P. Reeves; J. M. Scarr; K. Smith; M. G. Smith; A. S. Thompson; S. Thorn; R. M. Turnbull; U. Becker; O. Braun; C. Geweniger; P. Hanke; V. Hepp; E. E. Kluge; A. Putzer; B. Rensch; M. Schmidt; H. Stenzel; K. Tittel; M. Wunsch; R. Beuselinck; D. M. Binnie; W. Cameron; M. Cattaneo; D. J. Colling; P. J. Dornan; J. F. Hassard; N. Konstantinidis; L. Moneta; A. Moutoussi; J. Nash; D. G. Payne; G. San Martin; J. K. Sedgbeer; A. G. Wright; P. Girtler; D. Kuhn; G. Rudolph; R. Vogl; C. K. Bowdery; T. J. Brodbeck; A. J. Finch; F. Foster; G. Hughes; D. Jackson; N. R. Keemer; M. Nuttall; A. Patel; T. Sloan; S. W. Snow; E. P. Whelan; A. Galla; A. M. Greene; K. Kleinknecht; J. Raab; B. Renk; H.-G. Sander; H. Schmidt; S. M. Walther; R. Wanke; B. Wolf; A. M. Bencheikh; C. Benchouk; A. Bonissent; D. Calvet; J. Carr; C. Diaconu; F. Etienne; D. Nicod; P. Payre; L. Roos; D. Rousseau; P. Schwemling; M. Talby; S. Adlung; R. Assmann; C. Bauer; W. Blum; D. Brown; P. Cattaneo; B. Dehning; H. Dietl; F. Dydak; M. Frank; A. W. Halley; K. Jakobs; H. Kroha; J. Lauber; G. Lütjens; G. Lutz; W. Männer; H.-G. Moser; R. Richter; S. Schael; J. Schröder; A. S. Schwarz; R. Settles; H. Seywerd; U. Stierlin; U. Stiegler; R. St. Denis; G. Wolf; R. Alemany; J. Boucrot; O. Callot; A. Cordier; F. Courault; M. Davier; L. Duflot; J.-F. Grivaz; Ph. Heusse; P. Janot; M. Jacquet; D. W. Kimtr; F. Le Diberder; J. Lefrançois; A.-M. Lutz; G. Musolino; I. Nikolic; H. J. Park; I. C. Park; S. Simion; M.-H. Schune; J.-J. Veillet; I. Videau; D. Abbaneo; G. Bagliesi; G. Batignani; U. Bottigli; C. Bozzi; G. Calderini; M. Carpinelli; M. A. Ciocci; V. Ciulli; R. dell'Orso; I. Ferrante; F. Fidecaro; L. Foà; F. Forti; A Gregorio; M. A. Giorgi; F. Ligabue; A. Lusiani; P. S. Marrocchesi; E. B. Martin; A. Messineo; G. Rizzo; G. Sanguinetti; P. Spagnolo; J. Steinberger; R. Tenchini; G. Tonelli; G. Triggiani; C. Vannini; P. G. Verdini; J. Walsh; A. P. Betteridge; Y. Gao; M. G. Green; D. L. Johnson; P. V. March; T. Medcalf; Ll. M. Mir; I. S. Quazi; J. A. Strong; V. Bertin; D. R. Botterill; R. W. Clifft; T. R. Edgecock; S. Haywood; M. Edwards; P. R. Norton; J. C. Thompson; B. Bloch-Devaux; P. Colas; H. Duarte; S. Emery; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; B. Marx; P. Perez; J. Rander; J.-F. Renardy; A. Rosowsky; A. Roussarie; J.-P. Schuller; J. Schwindling; D. Si Mohand; B. Vallage; R. P. Johnson; A. M. Litke; G. Taylor; J. Wear; A. Beddall; C. N. Booth; S. Cartwright; F. Combley; I. Dawson; A. Koksal; C. Rankin; L. F. Thompson; A. Böhrer; S. Brandt; G. Cowan; E. Feigl; C. Grupen; G. Lutters; J. Minguet-Rodriguez; F. Rivera; P. Saraiva; U. Schäfer; L. Smolik; L. Bosisio; R. della Marina; G. Giannini; B. Gobbo; L. Pitis; F. Ragusa; L. Bellantoni; J. S. Conway; Z. Feng

1994-01-01

249

Fabrication of 94Zr thin target for recoil distance doppler shift method of lifetime measurement  

NASA Astrophysics Data System (ADS)

A thin isotopic 94Zr target of thickness 520 ?g/cm2 has been prepared for recoil distance Doppler shift method (RDM) lifetime measurement by using an electron beam deposition method on tantalum backing of 3.5 mg/cm2 thickness at Inter University Accelerator Center (IUAC), New Delhi. To meet the special requirement of smoothness of surface for RDM lifetime measurement and also to protect the outer layer of 94Zr from peeling off, a very thin layer of gold has been evaporated on a 94Zr target on a specially designed substrate holder. In all, 143 mg of 99.6% enriched 94Zr target material was utilized for the fabrication of 94Zr targets. The target has been successfully used in a recent RDM lifetime measurement experiment at IUAC.

Gupta, C. K.; Rohilla, Aman; Abhilash, S. R.; Kabiraj, D.; Singh, R. P.; Mehta, D.; Chamoli, S. K.

2014-11-01

250

Measurement of the B{sub s}{sup 0} Lifetime Using Semileptonic Decays  

SciTech Connect

We report a measurement of the B{sub s}{sup 0} lifetime in the semileptonic decay channel B{sub s}{sup 0}{yields}D{sub s}{sup -}{mu}{sup +}{nu}X (and its charge conjugate), using approximately 0.4 fb{sup -1} of data collected with the D0 detector during 2002-2004. Using 5176 reconstructed D{sub s}{sup -}{mu}{sup +} signal events, we have measured the B{sub s}{sup 0} lifetime to be {tau}(B{sub s}{sup 0})=1.398{+-}0.044(stat){sub -0.025}{sup +0.028}(syst) ps. This is the most precise measurement of the B{sub s}{sup 0} lifetime to date.

Abazov, V. M.; Alexeev, G. D.; Bandurin, D. V.; Kalinin, A. M.; Kharzheev, Y. M.; Malyshev, V. L.; Tokmenin, V. V.; Vertogradov, L. S.; Yatsunenko, Y. A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Abbott, B.; Gutierrez, P.; Hall, I.; Jain, S.; Kopal, M.; Pompos, A.; Severini, H.; Skubic, P.; Strauss, M. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Abolins, M.; Benitez, J. A. [Michigan State University, East Lansing, Michigan 48824 (United States)] (and others)

2006-12-15

251

Extended lifetime MCP-PMTs: Characterisation and lifetime measurements of ALD coated microchannel plates, in a sealed photomultiplier tube  

NASA Astrophysics Data System (ADS)

Atomic layer deposition (ALD) coating of microchannel plates (MCP) has been shown to offer significant performance advantages in MCP-PMTs (MCP Photomultiplier Tube). ALD is a chemical vapour process used to deposit atomic mono-layers on a substrate. A process has been developed to deposit a surface with improved secondary emission yield (SEY) on to an MCP substrate. The principal advantage of a higher SEY is the ability to achieve significantly higher gain at the same operating voltage across a single MCP. Further to this, it is suspected the atomic mono-layers deposited by ALD coating prevent desorption of gaseous contaminants in the MCP glass. The ions produced during desorption are widely believed to be a direct cause of photocathode ageing in MCP-PMTs, leading to the hope that ALD coating can improve the MCP-PMT lifetime. To fully characterise the performance of ALD coated MCPs, two MCP-PMTs were manufactured, one ALD coated and the other uncoated to be used as a reference. Each detector's gain, DQE, pulse shape and timing jitter were measured followed by a life test of the tubes. The ALD coated tube was found to have a higher gain at the same operating voltage, whilst being equivalent to a standard MCP in other performance characteristics. ALD coating gave a dramatically improved life time, after 5.16 C cm-2 total charge extracted, there was no measurable effect on the photocathode QE, although the MCP gain dropped by approximately 35%.

Conneely, Thomas M.; Milnes, James S.; Howorth, Jon

2013-12-01

252

A precise measurement of the tau lepton lifetime  

Microsoft Academic Search

Three different techniques are used to measure the mean decay length of the tau lepton with a high precision vertex detector in a sample of 11 800 tau pairs coming from Z decays, collected in1991 by ALEPH at LEP. Events in which both tau's decay into one charged track are analyzed using two largely independent methods. Displaced vertices in three-prong

Damir Buskulic; D. Decamp; C. Goy; J.-P. Lees; M.-N. Minard; B. Mours; R. Alemany; F. Ariztizabal; P. Comas; J. M. Crespo; M C Delfino; E. Fernandez; V. Gaitan; Ll. Garrido; T S Mattison; A. Pacheco; C. Padilla; A. Pascual; D. Creanza; M. de Palma; A. Farilla; Giuseppe Iaselli; G. Maggi; M. Maggi; S. Natali; S. Nuzzo; M. Quattromini; A. Ranieri; G. Raso; F. Romano; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; G. Zito; H. Hu; D. Huang; X. Huang; J. Lin; J. Lou; C. Qiao; T. Wang; Y. Xie; D. Xu; R. Xu; J. Zhang; W. Zhao; L. A. T. Bauerdick; E. Blucher; G. Bonvicini; F. Bossi; J. Boudreau; D. Casper; H. Drevermann; R. W. Forty; G. Ganis; C. Gay; R. Hagelberg; J. Harvey; S. Haywood; J. Hilgart; R. Jacobsen; B. Jost; J. Knobloch; E. Lançon; I. Lehraus; T. Lohse; A. Lusiani; M. Martinez; P. Mato; H. Meinhard; A. Minten; R. Miquel; H.-G. Moser; P. Palazzi; J F Pusztaszeri; F. Ranjard; G. Redlinger; L. Rolandi; J. Rothberg; T. Ruan; M. Saich; D. Schlatter; M. Schmelling; F. Sefkow; W. Tejessy; H. Wachsmuth; W. Wiedenmann; T. Wildish; W. Witzeling; J. Wotschack; Z. Ajaltouni; F. Badaud; M. Bardadin-Otwinowska; A. M. Bencheikh; R. El Fellous; A. Falvard; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; J.-C. Montret; D. Pallin; P. Perret; B. Pietrzyk; J. Proriol; F. Prulhiére; G. Stimpfl; T. Fearnley; J. D. Hansen; J. R. Hansen; R. Møllerud; B. S. Nilsson; I. Efthymiopoulos; A. Kyriakis; Errietta Simopoulou; Anna Vayaki; K. Zachariadou; J. Badier; A. Blondel; G R Bonneaud; J. C. Brient; G. Fouque; S. Orteu; A. Rosowsky; A. Rougé; M. Rumpf; R. Tanaka; M. Verderi; H L Videau; D. J. Candlin; M. I. Parsons; E. Veitch; L. Moneta; G. Parrini; M. Corden; C H Georgiopoulos; M. Ikeda; J E Lannutti; D A Levinthal; Michael E Mermikides; L. Sawyer; S R Wasserbaech; A. Antonelli; R. Baldini; G. Bencivenni; G. Bologna; P. Campana; G. Capon; F. Cerutti; V. Chiarella; B. D'Ettorre-Piazzoli; G. Felici; P. Laurelli; G. Mannocchi; F. Murtas; G. P. Murtas; L. Passalacqua; M. Pepe-Altarelli; P. Picchi; B. Altoon; O. Boyle; P. Colrain; I. Ten Have; J. G. Lynch; W. Maitland; C. Raine; J. M. Scarr; K. Smith; A. S. Thompson; R. M. Turnbull; B. Brandl; O. Braun; C. Geweniger; P. Hanke; V. Hepp; E. E. Kluge; Y. Maumary; A. Putzer; B. Rensch; A. Stahl; K. Tittel; M. Wunsch; A. T. Belk; R. Beuselinck; D. M. Binnie; W. Cameron; M. Cattaneo; D. J. Colling; P. J. Dornan; S. Dugeay; A. M. Greene; J. F. Hassard; N. M. Lieske; J. Nash; S. J. Patton; D. G. Payne; M. J. Phillips; J. K. Sedgbeer; I. R. Tomalin; A. G. Wright; E. Kneringer; D. Kuhn; G. Rudolph; C. K. Bowdery; T. J. Brodbeck; A. J. Finch; F. Foster; G. Hughes; D. Jackson; N. R. Kreemer; M. Nuttall; A. Patel; T. Sloan; S. W. Snow; E. P. Whelan; K. Kleinknecht; J. Raab; B. Renk; H.-G. Sander; H. Schmidt; F. Steeg; S. M. Walther; B. Wolf; J.-J. Aubert; C. Benchouk; A. Bonissent; J. Carr; P. Coyle; J. Drinkard; F. Etienne; S. Papalexiou; P. Payre; Z. Qian; L. Roos; D. Rousseau; P. Schwemling; M. Talby; S. Adlung; C. Bauer; W. Blum; D. Brown; P. Cattaneo; G. Cowan; B. Dehning; H. Dietl; F. Dydak; M. Fernandez-Bosman; M. Frank; A. W. Halley; J. Lauber; G. Lütjens; G. Lutz; W. Männer; R. Richter; H. Rotscheidt; J. Schröder; A. S. Schwarz; R. Settles; H. Seywerd; U. Stierlin; U. Stiegler; R. St. Denis; M. Takashima; J. Thomas; G. Wolf; J. Boucrot; O. Callot; A. Cordier; M. Davier; J.-F. Grivaz; Ph. Heusse; D. E. Jaffe; P. Janot; D. W. Kim; F. Le Diberder; J. Lefrançois; A.-M. Lutz; M.-H. Schune; J.-J. Veillet; I. Videau; Z. Zhang; D. Abbaneo; S. R. Amendolia; G. Bagliesi; G. Batignani; L. Bosisio; U. Bottigli; C. Bozzi; C. Bradaschia; M. Carpinelli; M. A. Ciocci; R. dell'Orso; I. Ferrante; F. Fidecaro; L. Foá; E. Focardi; A. Giassi; M. A. Giorgi; F. Ligabue; E. B. Mannelli; P. S. Marrocchesi; A. Messineo; F. Palla; G. Rizzo; G. Sanguinetti; P. Spagnolo; J. Steinberger; R. Tenchini; G. Tonelli; G. Triggiani; C. Vannini; A. Venturi; P. G. Verdini; J. Walsh; J. M. Carter; M. G. Green; P. V. March; Ll. M. Mir; T. Medcalf; I. S. Quazi; J. A. Strong; L. R. West; D. R. Botterill; R. W. Clifft; T. R. Edgecock; M. Edwards; S. M. Fisher; T. J. Jones; P. R. Norton; D. P. Salmon; J. C. Thompson; B. Bloch-Devaux; P. Colas; H. Duarte; W. Kozanecki; M. C. Lemaire; E. Locci; S. Loucatos; E. Monnier; P. Perez; F. Perrier; J. Rander; J.-F. Renardy; A. Roussarie; J.-P. Schuller; J. Schwindling; D. Si Mohand; B. Vallage; R. P. Johnson; A. M. Litke; G. Taylor; J. Wear; J. G. Ashman; W. Babbage; C. N. Booth; C. Buttar; R. E. Carney; S. Cartwright; F. Combley; F. Hatfield; P. Reeves; L. F. Thompson; E. Barberio; A. Böhrer; S. Brandt; C. Grupen; F. Rivera; U. Schäfer; G. Giannini; B. Gobbo; F. Ragusa; L. Bellantoni; W. Chen; D. Cinabro; J. S. Conway; D. F. Cowen; Z. Feng; D. P. S. Ferguson; Y. S. Gao; J. Grahl; J. L. Harton; R. C. Jared; B. W. Leclaire; C. Lishka

1992-01-01

253

Measurement of the Ratio of B+ and B0 Meson Lifetimes  

Microsoft Academic Search

The ratio of the B+ and B0 meson lifetimes was measured using data collected in 2002 2004 by the D0 experiment in Run II of the Fermilab Tevatron Collider. These mesons were reconstructed in B-->mu+nuD*-X decays, which are dominated by B0 and B-->mu+nuD¯0X decays, which are dominated by B+. The ratio of lifetimes is measured to be tau+\\/tau0=1.080±0.016(stat)±0.014(syst).

V. M. Abazov; B. Abbott; M. Abolins; B. S. Acharya; M. Adams; T. Adams; M. Agelou; J.-L. Agram; S. H. Ahn; M. Ahsan; G. D. Alexeev; G. Alkhazov; A. Alton; G. Alverson; G. A. Alves; M. Anastasoaie; S. Anderson; B. Andrieu; Y. Arnoud; A. Askew; B. Åsman; O. Atramentov; C. Autermann; C. Avila; F. Badaud; A. Baden; B. Baldin; P. W. Balm; S. Banerjee; E. Barberis; P. Bargassa; P. Baringer; C. Barnes; J. F. Bartlett; U. Bassler; D. Bauer; A. Bellavance; S. Beauceron; M. Begel; S. B. Beri; G. Bernardi; R. Bernhard; I. Bertram; M. Besançon; R. Beuselinck; V. A. Bezzubov; P. C. Bhat; V. Bhatnagar; M. Binder; K. M. Black; I. Blackler; G. Blazey; F. Blekman; S. Blessing; D. Bloch; U. Blumenschein; A. Boehnlein; O. Boeriu; T. A. Bolton; F. Borcherding; G. Borissov; K. Bos; T. Bose; A. Brandt; R. Brock; G. Brooijmans; A. Bross; N. J. Buchanan; D. Buchholz; M. Buehler; V. Buescher; S. Burdin; T. H. Burnett; E. Busato; J. M. Butler; J. Bystricky; W. Carvalho; B. C. Casey; N. M. Cason; H. Castilla-Valdez; S. Chakrabarti; D. Chakraborty; K. M. Chan; A. Chandra; D. Chapin; F. Charles; E. Cheu; L. Chevalier; D. K. Cho; S. Choi; T. Christiansen; L. Christofek; D. Coppage; B. Clément; C. Clément; Y. Coadou; M. Cooke; W. E. Cooper; M. Corcoran; J. Coss; A. Cothenet; M.-C. Cousinou; S. Crépé-Renaudin; M. Cristetiu; M. A. Cummings; D. Cutts; H. da Motta; B. Davies; G. Davies; G. A. Davis; K. de; P. de Jong; S. J. de Jong; E. de La Cruz-Burelo; C. de Oliveira Martins; S. Dean; F. Déliot; P. A. Delsart; M. Demarteau; R. Demina; P. Demine; D. Denisov; S. P. Denisov; S. Desai; H. T. Diehl; M. Diesburg; M. Doidge; H. Dong; S. Doulas; L. Duflot; S. R. Dugad; A. Duperrin; J. Dyer; A. Dyshkant; M. Eads; D. Edmunds; T. Edwards; J. Ellison; J. Elmsheuser; J. T. Eltzroth; V. D. Elvira; S. Eno; P. Ermolov; O. V. Eroshin; J. Estrada; D. Evans; H. Evans; A. Evdokimov; V. N. Evdokimov; J. Fast; S. N. Fatakia; L. Feligioni; T. Ferbel; F. Fiedler; F. Filthaut; W. Fisher; H. E. Fisk; M. Fortner; H. Fox; W. Freeman; S. Fu; S. Fuess; T. Gadfort; C. F. Galea; E. Gallas; E. Galyaev; C. Garcia; A. Garcia-Bellido; J. Gardner; V. Gavrilov; P. Gay; D. Gelé; R. Gelhaus; K. Genser; C. E. Gerber; Y. Gershtein; G. Ginther; T. Golling; B. Gómez; K. Gounder; A. Goussiou; P. D. Grannis; S. Greder; H. Greenlee; Z. D. Greenwood; E. M. Gregores; Ph. Gris; J.-F. Grivaz; L. Groer; S. Grünendahl; M. W. Grünewald; S. N. Gurzhiev; G. Gutierrez; P. Gutierrez; A. Haas; N. J. Hadley; S. Hagopian; I. Hall; R. E. Hall; C. Han; L. Han; K. Hanagaki; K. Harder; R. Harrington; J. M. Hauptman; R. Hauser; J. Hays; T. Hebbeker; D. Hedin; J. M. Heinmiller; A. P. Heinson; U. Heintz; C. Hensel; G. Hesketh; M. D. Hildreth; R. Hirosky; J. D. Hobbs; B. Hoeneisen; M. Hohlfeld; S. J. Hong; R. Hooper; P. Houben; Y. Hu; J. Huang; I. Iashvili; R. Illingworth; A. S. Ito; S. Jabeen; M. Jaffré; S. Jain; V. Jain; K. Jakobs; A. Jenkins; R. Jesik; K. Johns; M. Johnson; A. Jonckheere; P. Jonsson; H. Jöstlein; A. Juste; M. M. Kado; D. Käfer; W. Kahl; S. Kahn; E. Kajfasz; A. M. Kalinin; J. Kalk; D. Karmanov; J. Kasper; D. Kau; R. Kehoe; S. Kermiche; S. Kesisoglou; A. Khanov; A. Kharchilava; Y. M. Kharzheev; K. H. Kim; B. Klima; M. Klute; J. M. Kohli; M. Kopal; V. M. Korablev; J. Kotcher; B. Kothari; A. Koubarovsky; A. V. Kozelov; J. Kozminski; S. Krzywdzinski; S. Kuleshov; Y. Kulik; S. Kunori; A. Kupco; T. Kurca; S. Lager; N. Lahrichi; G. Landsberg; J. Lazoflores; A.-C. Le Bihan; P. Lebrun; S. W. Lee; W. M. Lee; A. Leflat; F. Lehner; C. Leonidopoulos; P. Lewis; J. Li; Q. Z. Li; J. G. Lima; D. Lincoln; S. L. Linn; J. Linnemann; V. V. Lipaev; R. Lipton; L. Lobo; A. Lobodenko; M. Lokajicek; A. Lounis; H. J. Lubatti; L. Lueking; M. Lynker; A. L. Lyon; A. K. Maciel; R. J. Madaras; P. Mättig; A. Magerkurth; A.-M. Magnan; N. Makovec; P. K. Mal; S. Malik; V. L. Malyshev; H. S. Mao; Y. Maravin; M. Martens; S. E. Mattingly; A. A. Mayorov; R. McCarthy; R. McCroskey; D. Meder; H. L. Melanson; A. Melnitchouk; M. Merkin; K. W. Merritt; A. Meyer; H. Miettinen; D. Mihalcea; J. Mitrevski; N. Mokhov; J. Molina; N. K. Mondal; H. E. Montgomery; R. W. Moore; G. S. Muanza; M. Mulders; Y. D. Mutaf; E. Nagy; M. Narain; N. A. Naumann; H. A. Neal; J. P. Negret; S. Nelson; P. Neustroev; C. Noeding; A. Nomerotski; S. F. Novaes; T. Nunnemann; E. Nurse; V. O'dell; D. C. O'Neil; V. Oguri; N. Oliveira; N. Oshima; G. J. Otero Y Garzón; P. Padley; N. Parashar; S. K. Park; J. Parsons; R. Partridge; N. Parua; A. Patwa; P. M. Perea; E. Perez; O. Peters; P. Pétroff; M. Petteni; L. Phaf; R. Piegaia; P. L. Podesta-Lerma; V. M. Podstavkov; Y. Pogorelov; B. G. Pope; W. L. Prado da Silva; H. B. Prosper; S. Protopopescu; M. B. Przybycien; J. Qian; A. Quadt; B. Quinn; K. J. Rani; P. A. Rapidis; P. N. Ratoff; N. W. Reay; S. Reucroft; M. Rijssenbeek; I. Ripp-Baudot; F. Rizatdinova; C. Royon; P. Rubinov

2005-01-01

254

Measurement of the ratio of B+ and B0 meson lifetimes.  

PubMed

The ratio of the B+ and B0 meson lifetimes was measured using data collected in 2002-2004 by the D0 experiment in Run II of the Fermilab Tevatron Collider. These mesons were reconstructed in B-->mu(+)nuD(*-)X decays, which are dominated by B0 and B-->mu(+)nuD 0X decays, which are dominated by B+. The ratio of lifetimes is measured to be tau(+)/tau(0)=1.080+/-0.016(stat)+/-0.014(syst). PMID:15904361

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Anderson, S; Andrieu, B; Arnoud, Y; Askew, A; Asman, B; Atramentov, O; Autermann, C; Avila, C; Badaud, F; Baden, A; Baldin, B; Balm, P W; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beauceron, S; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burnett, T H; Busato, E; Butler, J M; Bystricky, J; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevalier, L; Cho, D K; Choi, S; Christiansen, T; Christofek, L; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Coss, J; Cothenet, A; Cousinou, M-C; Crépé-Renaudin, S; Cristetiu, M; Cummings, M A C; Cutts, D; da Motta, H; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Dean, S; Déliot, F; Delsart, P A; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dong, H; Doulas, S; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Eltzroth, J T; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, D; Evans, H; Evdokimov, A; Evdokimov, V N; Fast, J; Fatakia, S N; Feligioni, L; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Freeman, W; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Y; Ginther, G; Golling, T; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Gris, Ph; Grivaz, J-F; Groer, L; Grünendahl, S; Grünewald, M W; Gurzhiev, S N; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hanagaki, K; Harder, K; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Huang, J; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jenkins, A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jonsson, P; Jöstlein, H; Juste, A; Kado, M M; Käfer, D; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Karmanov, D; Kasper, J; Kau, D; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A; Kharzheev, Y M; Kim, K H; Klima, B; Klute, M; Kohli, J M; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Krzywdzinski, S; Kuleshov, S; Kulik, Y; Kunori, S; Kupco, A; Kurca, T; Lager, S; Lahrichi, N; Landsberg, G; Lazoflores, J; Le Bihan, A-C; Lebrun, P; Lee, S W; Lee, W M; Leflat, A; Lehner, F; Leonidopoulos, C; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Lubatti, H J; Lueking, L; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magerkurth, A; Magnan, A-M; Makovec, N; Mal, P K; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; Mayorov, A A; McCarthy, R; McCroskey, R; Meder, D; Melanson, H L; Melnitchouk, A; Merkin, M; Merritt, K W; Meyer, A; Miettinen, H; Mihalcea, D; Mitrevski, J; Mokhov, N; Molina, J; Mondal, N K; Montgomery, H E; Moore, R W; Muanza, G S; Mulders, M; Mutaf, Y D; Nagy, E; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; Nurse, E; O'Dell, V; O'Neil, D C; Oguri, V; Oliveira, N; Oshima, N; Otero y Garzón, G J; Padley, P; Parashar, N; Park, J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Perea, P M; Perez, E; Peters, O; Pétroff, P; Petteni, M; Phaf, L; Piegaia, R; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pope, B G; Prado da Silva, W L; Prosper, H B; Protopopescu, S; Przybycien, M B; Qian, J; Quadt, A; Quinn, B; Rani, K J; Rapidis, P A; Ratoff, P N; Reay, N W; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Royon, C; Rubinov, P; Ruchti, R; Sajot, G; Sánchez-Hernández, A; Sanders, M P

2005-05-13

255

Measurement of the Ratio of B{sup +} and B{sup 0} Meson Lifetimes  

SciTech Connect

The ratio of the B{sup +} and B{sup 0} meson lifetimes was measured using data collected in 2002-2004 by the D0 experiment in Run II of the Fermilab Tevatron Collider. These mesons were reconstructed in B{yields}{mu}{sup +}{nu}D{sup *-}X decays, which are dominated by B{sup 0} and B{yields}{mu}{sup +}{nu}D{sup 0}X decays, which are dominated by B{sup +}. The ratio of lifetimes is measured to be {tau}{sup +}/{tau}{sup 0}=1.080{+-}0.016(stat){+-}0.014(syst)

Abazov, V.M.; Alexeev, G.D.; Kalinin, A.M.; Kharzheev, Y.M.; Malyshev, V.L.; Vertogradov, L.S.; Yatsunenko, Y.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Abbott, B.; Gutierrez, P.; Hall, I.; Jain, S.; Kopal, M.; Severini, H.; Skubic, P.; Strauss, M.; Zhang, X. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Abolins, M.; Brock, R.; Dyer, J.; Edmunds, D. [Michigan State University, East Lansing, Michigan 48824 (United States)] [and others

2005-05-13

256

Nuclear matrix elements from direct lifetime or cross-section measurements  

SciTech Connect

The method of simultaneous lifetime and g factor measurements using a plunger device and the RDDS and TDRIV techniques is introduced. Results on lifetimes and hyperfine-interaction parameters for 2{sup +}{sub 1} states in {sup 104-108}Pd, {sup 96,98,104}Ru, and {sup 92,94}Zr, using a plunger device. Another method to obtain electromagnetic matrix elements is direct cross section measurements using NRF. The method is outlined, and some recent results on {sup 76}Se are shown.

Werner, V.; Cooper, N.; Hinton, M.; Ilie, G.; Radeck, D. [Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States); Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States) and Department of Physics, University of Surrey, Guilford, GU27XH (United Kingdom); Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States) and National Institute for Physics and Nuclear Engineering, P.O. Box MG-6, Bucharest-Magurele (Romania); Wright Nuclear Structure Laboratory, Yale University, P.O. Box 208120, New Haven, CT 06520-8120 (United States) and Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany)

2012-11-20

257

Interpreting aerosol lifetimes using the GEOS-Chem model and constraints from radionuclide measurements  

NASA Astrophysics Data System (ADS)

Aerosol removal processes control global aerosol abundance, but the rate of that removal remains uncertain. A recent study of aerosol-bound radionuclide measurements after the Fukushima Daiichi nuclear power plant accident documents 137Cs removal (e-folding) times of 10.0-13.9 days, suggesting that mean aerosol lifetimes in the range of 3-7 days in global models might be too short by a factor of two. In this study, we attribute this discrepancy to differences between the e-folding and mean aerosol lifetimes. We implement a simulation of 137Cs and 133Xe into the GEOS-Chem chemical transport model and examine the removal rates for the Fukushima case. We find a general consistency between modelled and measured e-folding times. The simulated 137Cs global burden e-folding time is about 14 days. However, the simulated mean lifetime of aerosol-bound 137Cs over a 6-month post-accident period is only 1.8 days. We find that the mean lifetime depends strongly on the removal rates in the first few days after emissions, before the aerosols leave the boundary layer and are transported to altitudes and latitudes where lifetimes with respect to wet removal are longer by a few orders of magnitude. We present sensitivity simulations that demonstrate the influence of differences in altitude and location of the radionuclides on the mean lifetime. Global mean lifetimes are shown to strongly depend on the altitude of injection. The global mean 137Cs lifetime is more than one order of magnitude greater for the injection at 7 km than into the boundary layer above the Fukushima site. Instantaneous removal rates are slower during the first few days after the emissions for a free tropospheric versus boundary layer injection and this strongly controls the mean lifetimes. Global mean aerosol lifetimes for the GEOS-Chem model are 3-6 days, which is longer than that for the 137Cs injected at the Fukushima site (likely due to precipitation shortly after Fukushima emissions), but similar to the mean lifetime of 3.9 days for the 137Cs emissions injected with a uniform spread through the model's Northern Hemisphere boundary layer. Simulated e-folding times were insensitive to emission parameters (altitude, location, and time), suggesting that these measurement-based e-folding times provide arobust constraint on simulated e-folding times. Despite the reasonable global mean agreement of GEOS-Chem with measurement e-folding times, site by site comparisons yield differences of up to a factor of two, which suggest possible deficiencies in either the model transport, removal processes or the representation of 137Cs removal, particularly in the tropics and at high latitudes. There is an ongoing need to develop constraints on aerosol lifetimes, but these measurement-based constraints must be carefully interpreted given the sensitivity of mean lifetimes and e-folding times to both mixing and removal processes.

Croft, B.; Pierce, J. R.; Martin, R. V.

2014-04-01

258

New measurements of the lifetimes of excited states of {sup 55}Mn below 2.7 MeV  

SciTech Connect

The lifetimes of the excited states of {sup 55}Mn between 1.5 and 2.7 MeV were measured using nuclear resonance fluorescence. The absolute lifetimes of the excited levels were determined from simultaneous measurements of manganese and aluminum. In this approach, the precisely known aluminum state serves as a means to normalize the results. Our findings differ from the evaluated level lifetimes in the Evaluated Nuclear Structure Data File (ENSDF), but agree with earlier nuclear resonance fluorescence measurements.

Caggiano, J. A.; Warren, G. A. [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Hasty, R. D.; Korbly, S. E.; Park, W. H. [Passport Systems Inc., Billerica, Massachusetts 01862 (United States)

2009-09-15

259

The Measurement of Radiative Lifetimes Using Laser-Induced Fluorescence: Experimental Review and Astrophysical Application  

NASA Astrophysics Data System (ADS)

One of the standard methods for determining atomic transition probabilities is to combine branching fractions measured using Fourier-transform spectrometry with radiative lifetimes measurements using laser-induced fluorescence (LIF). This combination of techniques provides an efficient method for measuring large sets of accurate, absolute transition probabilities. The radiative lifetimes, which provide the overall scaling for the transition probabilities, can be measured routinely to ± 5% accuracy using time-resolved LIF. Although the time-resolved LIF technique we use does not achieve the accuracy of fast-beam LIF, the time-resolved technique does enable us to make measurements at a far greater rate (hundreds of level lifetimes per year). Care must be taken, however, to understand and control the systematic effects in time-resolved LIF measurements to maintain ± 5% accuracy over a wide dynamic range and hundreds of lifetime measurements. Over the last 25 years, we have measured lifetimes for 47 spectra using time-resolved LIF. Our atomic beam source can produce a slow beam of neutral and singly ionized atoms of nearly any element. Lifetimes from 2 ns to ~2 µs can be measured for energy levels ranging from 15,000 to ~60,000 cm-1. In this review we will describe our method of measuring radiative lifetimes with an emphasis on possible errors and techniques used for controlling them. The electronic bandwidth, linearity, and overall fidelity of the fast photomultiplier, cable connections, and transient waveform digitizer are concerns. Possible errors from atomic collisions, radiation trapping, Zeeman quantum beats, hyperfine quantum beats, atoms/ions escaping from the observation region before radiating, and from radiative cascade through lower levels must be understood and controlled. We will then present a recent example of the application of our transition probability data to abundance determinations in the sun and in metal-poor halo stars (Den Hartog E A et al 2003 Astrophys. J. Suppl. 148 543). Our results have significantly reduced the uncertainty of abundance determinations for many elements including the rare-earths: La, Nd, Eu, Tb, Dy, Ho, Tm, and Lu. Better laboratory data have made it possible to cleanly separate the enhanced abundance of r(apid)-process neutron capture elements in metal poor Galactic halo stars. The long-term scientific payoff from this attention to detail in laboratory experiments is a better understanding of the r-process, of the Galactic chemical evolution, of the age of the oldest stars in the Galaxy, and indeed of the origins of the non-primordial chemical elements.

Den Hartog, E. A.; Lawler, J. E.; Sneden, C.

2005-01-01

260

Measurement of the B/s0 lifetime in B/s0 --> K+ K- decays  

SciTech Connect

A method is presented to simultaneously separate the contributions to a sample of B{sub (s)}{sup 0} {yields} h{sup +}h{sup {prime}-} decays, where h = {pi} or K, and measure the B meson lifetimes in the sample while correcting for the bias in the lifetime distributions due to the hadronic trigger at the CDF experiment. Using 1 fb{sup -1} of data collected at CDF the B{sup 0} lifetime is measured as {tau}{sub B{sup 0}} = 1.558{sub -0.047}{sup +0.050}{sub stat} {+-} 0.028{sub syst} ps, in agreement with the world average measurement. The B{sub s}{sup 0} lifetime in the B{sub s}{sup 0} {yields} K{sup +}K{sup -} decay is measured as {tau}{sub B{sub s}{sup 0} {yields} K{sup +}K{sup -}} = 1.51{sub -0.11}{sup +0.13}{sub stat} {+-} 0.04{sub syst} ps. No difference is observed between the lifetime and other measurements of the average B{sub s}{sup 0} lifetime or the lifetime of the light B{sub s}{sup 0} mass eigenstate determined from B{sub s}{sup 0} {yields} J/{psi}{phi} decays. With the assumptions that B{sub s}{sup 0} {yields} K{sup +}K{sup -} is 100% CP-even and that {tau}{sub B{sub s}{sup 0}} = {tau}{sub B{sup 0}} the width difference in the B{sub s}{sup 0} system is determined as {Delta}{Lambda}{sup CP}/{Lambda} = 0.03{sub -0.15}{sup +0.17}{sub stat} {+-} 0.05{sub syst} using the current world average B{sup 0} lifetime. This is consistent with zero and with the current world average measurement.

Pounder, Nicola Louise; /Oxford U.

2009-02-01

261

Noninvasive measurement of regional myocardial glucose metabolism by positron emission computed tomography. [Dogs  

SciTech Connect

While the results of regional myocardial glucose metabolism measurements using positron emission computed tomography (/sup 13/N-ammonia) are promising, their utility and value remains to be determined in man. If this technique can be applied to patients with acute myocardial ischemia or infarction it may permit delineation of regional myocardial segments with altered, yet still active metabolism. Further, it may become possible to evaluate the effects of interventions designed to salvage reversibly injured myocardium by this technique.

Schelbert, H.R.; Phelps, M.E.

1980-06-01

262

Plunger lifetime measurements after Coulomb excitation at intermediate beam energies  

SciTech Connect

Absolute transition probabilities of the first 2{sup +} state in {sup 110,114}Pd were remeasured using the recoil distance Doppler shift technique following projectile Coulomb excitation at intermediate beam energies for the first time. The {sup 110}Pd experiment served to check the novel technique as well as the method used for the data analysis which is based on the examination of {gamma}-ray lineshapes. Whereas the measured B(E2) value for {sup 110}Pd agrees very well with the literature, the value obtained for {sup 114}Pd differs considerably. The data is also used to test a novel concept, called the valence proton symmetry, which allows one to extrapolate nuclear properties to very neutron rich nuclei.

Dewald, A.; Hackstein, M.; Rother, W.; Jolie, J.; Melon, B.; Pissulla, T.; Shimbara, Y. [Institut fuer Kernphysik, Universitaet zu Koeln, 50937 Cologne (Germany); Starosta, K.; Adrich, P.; Amthor, A. M.; Baumann, T.; Bazin, D.; Bowen, M.; Chester, A.; Dunomes, A.; Gade, A.; Galaviz, D.; Glasmacher, T.; Ginter, T.; Hausmann, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)] (and others)

2009-01-28

263

Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station  

E-print Network

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ?30??GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

Aguilar, M; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Du, W J; Duranti, M; D’Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pedreschi, E; Pensotti, S; Pereira, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türko?lu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

2014-01-01

264

Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station.  

PubMed

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ?30??GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons. PMID:25279617

Aguilar, M; Aisa, D; Alvino, A; Ambrosi, G; Andeen, K; Arruda, L; Attig, N; Azzarello, P; Bachlechner, A; Barao, F; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Battarbee, M; Battiston, R; Bazo, J; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Bertucci, B; Bigongiari, G; Bindi, V; Bizzaglia, S; Bizzarri, M; Boella, G; de Boer, W; Bollweg, K; Bonnivard, V; Borgia, B; Borsini, S; Boschini, M J; Bourquin, M; Burger, J; Cadoux, F; Cai, X D; Capell, M; Caroff, S; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chikanian, A; Chou, H Y; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Consolandi, C; Contin, A; Corti, C; Coste, B; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirköz, M B; Derome, L; Di Falco, S; Di Masso, L; Dimiccoli, F; Díaz, C; von Doetinchem, P; Du, W J; Duranti, M; D'Urso, D; Eline, A; Eppling, F J; Eronen, T; Fan, Y Y; Farnesini, L; Feng, J; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Galaktionov, Y; Gallucci, G; García, B; García-López, R; Gast, H; Gebauer, I; Gervasi, M; Ghelfi, A; Gillard, W; Giovacchini, F; Goglov, P; Gong, J; Goy, C; Grabski, V; Grandi, D; Graziani, M; Guandalini, C; Guerri, I; Guo, K H; Habiby, M; Haino, S; Han, K C; He, Z H; Heil, M; Hoffman, J; Hsieh, T H; Huang, Z C; Huh, C; Incagli, M; Ionica, M; Jang, W Y; Jinchi, H; Kanishev, K; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Kunz, S; La Vacca, G; Laudi, E; Laurenti, G; Lazzizzera, I; Lebedev, A; Lee, H T; Lee, S C; Leluc, C; Li, H L; Li, J Q; Li, Q; Li, Q; Li, T X; Li, W; Li, Y; Li, Z H; Li, Z Y; Lim, S; Lin, C H; Lipari, P; Lippert, T; Liu, D; Liu, H; Lomtadze, T; Lu, M J; Lu, Y S; Luebelsmeyer, K; Luo, F; Luo, J Z; Lv, S S; Majka, R; Malinin, A; Mañá, C; Marín, J; Martin, T; Martínez, G; Masi, N; Maurin, D; Menchaca-Rocha, A; Meng, Q; Mo, D C; Morescalchi, L; Mott, P; Müller, M; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oliva, A; Orcinha, M; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Pedreschi, E; Pensotti, S; Pereira, R; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pohl, M; Poireau, V; Postaci, E; Putze, A; Quadrani, L; Qi, X M; Rancoita, P G; Rapin, D; Ricol, J S; Rodríguez, I; Rosier-Lees, S; Rozhkov, A; Rozza, D; Sagdeev, R; Sandweiss, J; Saouter, P; Sbarra, C; Schael, S; Schmidt, S M; Schuckardt, D; Schulz von Dratzig, A; Schwering, G; Scolieri, G; Seo, E S; Shan, B S; Shan, Y H; Shi, J Y; Shi, X Y; Shi, Y M; Siedenburg, T; Son, D; Spada, F; Spinella, F; Sun, W; Sun, W H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tescaro, D; Ting, Samuel C C; Ting, S M; Tomassetti, N; Torsti, J; Türko?lu, C; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vaurynovich, S; Vecchi, M; Velasco, M; Vialle, J P; Wang, L Q; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Weng, Z L; Whitman, K; Wienkenhöver, J; Wu, H; Xia, X; Xie, M; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J H; Zhang, M T; Zhang, X B; Zhang, Z; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zimmermann, N; Zuccon, P; Zurbach, C

2014-09-19

265

Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station  

NASA Astrophysics Data System (ADS)

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ˜30 GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

Aguilar, M.; Aisa, D.; Alvino, A.; Ambrosi, G.; Andeen, K.; Arruda, L.; Attig, N.; Azzarello, P.; Bachlechner, A.; Barao, F.; Barrau, A.; Barrin, L.; Bartoloni, A.; Basara, L.; Battarbee, M.; Battiston, R.; Bazo, J.; Becker, U.; Behlmann, M.; Beischer, B.; Berdugo, J.; Bertucci, B.; Bigongiari, G.; Bindi, V.; Bizzaglia, S.; Bizzarri, M.; Boella, G.; de Boer, W.; Bollweg, K.; Bonnivard, V.; Borgia, B.; Borsini, S.; Boschini, M. J.; Bourquin, M.; Burger, J.; Cadoux, F.; Cai, X. D.; Capell, M.; Caroff, S.; Casaus, J.; Cascioli, V.; Castellini, G.; Cernuda, I.; Cervelli, F.; Chae, M. J.; Chang, Y. H.; Chen, A. I.; Chen, H.; Cheng, G. M.; Chen, H. S.; Cheng, L.; Chikanian, A.; Chou, H. Y.; Choumilov, E.; Choutko, V.; Chung, C. H.; Clark, C.; Clavero, R.; Coignet, G.; Consolandi, C.; Contin, A.; Corti, C.; Coste, B.; Cui, Z.; Dai, M.; Delgado, C.; Della Torre, S.; Demirköz, M. B.; Derome, L.; Di Falco, S.; Di Masso, L.; Dimiccoli, F.; Díaz, C.; von Doetinchem, P.; Du, W. J.; Duranti, M.; D'Urso, D.; Eline, A.; Eppling, F. J.; Eronen, T.; Fan, Y. Y.; Farnesini, L.; Feng, J.; Fiandrini, E.; Fiasson, A.; Finch, E.; Fisher, P.; Galaktionov, Y.; Gallucci, G.; García, B.; García-López, R.; Gast, H.; Gebauer, I.; Gervasi, M.; Ghelfi, A.; Gillard, W.; Giovacchini, F.; Goglov, P.; Gong, J.; Goy, C.; Grabski, V.; Grandi, D.; Graziani, M.; Guandalini, C.; Guerri, I.; Guo, K. H.; Habiby, M.; Haino, S.; Han, K. C.; He, Z. H.; Heil, M.; Hoffman, J.; Hsieh, T. H.; Huang, Z. C.; Huh, C.; Incagli, M.; Ionica, M.; Jang, W. Y.; Jinchi, H.; Kanishev, K.; Kim, G. N.; Kim, K. S.; Kirn, Th.; Kossakowski, R.; Kounina, O.; Kounine, A.; Koutsenko, V.; Krafczyk, M. S.; Kunz, S.; La Vacca, G.; Laudi, E.; Laurenti, G.; Lazzizzera, I.; Lebedev, A.; Lee, H. T.; Lee, S. C.; Leluc, C.; Li, H. L.; Li, J. Q.; Li, Q.; Li, Q.; Li, T. X.; Li, W.; Li, Y.; Li, Z. H.; Li, Z. Y.; Lim, S.; Lin, C. H.; Lipari, P.; Lippert, T.; Liu, D.; Liu, H.; Lomtadze, T.; Lu, M. J.; Lu, Y. S.; Luebelsmeyer, K.; Luo, F.; Luo, J. Z.; Lv, S. S.; Majka, R.; Malinin, A.; Mañá, C.; Marín, J.; Martin, T.; Martínez, G.; Masi, N.; Maurin, D.; Menchaca-Rocha, A.; Meng, Q.; Mo, D. C.; Morescalchi, L.; Mott, P.; Müller, M.; Ni, J. Q.; Nikonov, N.; Nozzoli, F.; Nunes, P.; Obermeier, A.; Oliva, A.; Orcinha, M.; Palmonari, F.; Palomares, C.; Paniccia, M.; Papi, A.; Pedreschi, E.; Pensotti, S.; Pereira, R.; Pilo, F.; Piluso, A.; Pizzolotto, C.; Plyaskin, V.; Pohl, M.; Poireau, V.; Postaci, E.; Putze, A.; Quadrani, L.; Qi, X. M.; Rancoita, P. G.; Rapin, D.; Ricol, J. S.; Rodríguez, I.; Rosier-Lees, S.; Rozhkov, A.; Rozza, D.; Sagdeev, R.; Sandweiss, J.; Saouter, P.; Sbarra, C.; Schael, S.; Schmidt, S. M.; Schuckardt, D.; von Dratzig, A. Schulz; Schwering, G.; Scolieri, G.; Seo, E. S.; Shan, B. S.; Shan, Y. H.; Shi, J. Y.; Shi, X. Y.; Shi, Y. M.; Siedenburg, T.; Son, D.; Spada, F.; Spinella, F.; Sun, W.; Sun, W. H.; Tacconi, M.; Tang, C. P.; Tang, X. W.; Tang, Z. C.; Tao, L.; Tescaro, D.; Ting, Samuel C. C.; Ting, S. M.; Tomassetti, N.; Torsti, J.; Türko?lu, C.; Urban, T.; Vagelli, V.; Valente, E.; Vannini, C.; Valtonen, E.; Vaurynovich, S.; Vecchi, M.; Velasco, M.; Vialle, J. P.; Wang, L. Q.; Wang, Q. L.; Wang, R. S.; Wang, X.; Wang, Z. X.; Weng, Z. L.; Whitman, K.; Wienkenhöver, J.; Wu, H.; Xia, X.; Xie, M.; Xie, S.; Xiong, R. Q.; Xin, G. M.; Xu, N. S.; Xu, W.; Yan, Q.; Yang, J.; Yang, M.; Ye, Q. H.; Yi, H.; Yu, Y. J.; Yu, Z. Q.; Zeissler, S.; Zhang, J. H.; Zhang, M. T.; Zhang, X. B.; Zhang, Z.; Zheng, Z. M.; Zhuang, H. L.; Zhukov, V.; Zichichi, A.; Zimmermann, N.; Zuccon, P.; Zurbach, C.; AMS Collaboration

2014-09-01

266

Influence of fluorescence anisotropy on fluorescence intensity and lifetime measurement: theory, Simulations and experiments  

Microsoft Academic Search

The significance of fluorescence anisotropy in fluorescence intensity and lifetime measurements, and erroneous measurements and interpretations resulting from its disregard, are thoroughly discussed, formulated and quantified. In all fluorescence-related measurements-including excitation and emission spectra, relative fluorescence intensity (FI), fluorescenc life time (FLT), fluorescence resonance energy transfer (FRET), etc., with the exception of fluorescence polarization and anisotropy-it is generally true that

Dror Fixler; Yaniv Namer; Yitshak Yishay; Mordechai Deutsch

2006-01-01

267

A measurement of B+ and B0 lifetimes usingbar Dell ^ + events  

Microsoft Academic Search

A measurement of B meson lifetimes is presented using data collected from 1991 to 1993 by the DELPHI detector at the LEP collider. Samples of events with a D meson and a lepton in the same jet are selected wherebar D^{^0 } ell ^ + and D*l+ events originate mainly from the semileptonic decays of B+ and B0 mesons, respectively.

P. Abreu; W. Adam; T. Adye; E. Agasi; I. Ajinenko; R. Aleksan; G. D. Alekseev; P. P. Allport; S. Almehed; S. J. Alvsvaag; U. Amaldi; S. Amato; A. Andreazza; M. L. Andrieux; P. Antilogus; W.-D. Apel; Y. Arnoud; B. Åsman; J.-E. Augustin; A. Augustinus; P. Baillon; P. Bambade; F. Barao; R. Barate; G. Barbiellini; D. Y. Bardin; G. J. Barker; A. Baroncelli; O. Barring; J. A. Barrio; W. Bartl; M. J. Bates; M. Battaglia; M. Baubillier; J. Baudot; K.-H. Becks; M. Begalli; P. Beilliere; Yu. Belokopytov; A. C. Benvenuti; M. Berggren; D. Bertrand; F. Bianchi; M. Bigi; M. S. Bilenky; P. Billoir; D. Bloch; M. Blume; S. Blyth; V. Bocci; T. Bolognese; M. Bonesini; W. Bonivento; P. S. L. Booth; G. Borisov; C. Bosio; S. Bosworth; O. Botner; B. Bouquet; C. Bourdarios; T. J. V. Bowcock; M. Bozzo; P. Branchini; K. D. Brand; R. A. Brenner; C. Bricman; L. Brillault; R. C. A. Brown; P. Bruckman; J.-M. Brunet; L. Bugge; T. Buran; A. Buys; M. Caccia; M. Calvi; A. J. Camacho Rozas; T. Camporesi; V. Canale; M. Canepa; K. Cankocak; F. Cao; F. Carena; P. Carrilho; L. Carroll; C. Caso; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; L. Cerrito; V. Chabaud; M. Chapkin; Ph. Charpentier; L. Chaussard; J. Chauveau; P. Checchia; G. A. Chelkov; R. Chierici; P. Chliapnikov; P. Chochula; V. Chorowicz; V. Cindro; P. Collins; J. L. Contreras; R. Contri; E. Cortina; G. Cosme; F. Cossutti; H. B. Crawley; D. Crennell; G. Crosetti; J. Cuevas Maestro; S. Czellar; E. Dahl-Jensen; J. Dahm; B. Dalmagne; M. Dam; G. Damgaard; A. Daum; P. D. Dauncey; M. Davenport; W. da Silva; C. Defoix; G. Della Ricca; P. Delpierre; N. Demaria; A. de Angelis; H. de Boeck; W. de Boer; S. de Brabandere; C. de Clercq; C. de La Vaissiere; B. de Lotto; A. de Min; L. de Paula; C. de Saint-Jean; H. Dijkstra; L. di Ciaccio; F. Djama; J. Dolbeau; M. Donszelmann; K. Doroba; M. Dracos; J. Drees; K.-A. Drees; M. Dris; Y. Dufour; F. Dupont; D. Edsall; R. Ehret; G. Eigen; T. Ekelof; G. Ekspong; M. Elsing; J.-P. Engel; N. Ershaidat; B. Erzen; E. Falk; D. Fassouliotis; M. Feindt; A. Fenyuk; A. Ferrer; T. A. Filippas; A. Firestone; P.-A. Fischer; H. Foeth; E. Fokitis; F. Fontanelli; F. Formenti; B. Franek; P. Frenkiel; D. C. Fries; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; H. Furstenau; J. Fuster; A. Galloni; D. Gamba; M. Gandelman; C. Garcia; J. Garcia; C. Gaspar; U. Gasparini; Ph. Gavillet; E. N. Gazis; D. Gele; J.-P. Gerber; M. Gibbs; D. Gillespie; R. Gokieli; B. Golob; G. Gopal; L. Gorn; M. Gorski; Yu. Gouz; V. Gracco; E. Graziani; G. Grosdidier; P. Gunnarsson; M. Gunther; J. Guy; U. Haedinger; F. Hahn; M. Hahn; S. Hahn; Z. Hajduk; A. Hallgren; K. Hamacher; W. Hao; F. J. Harris; V. Hedberg; R. Henriques; J. J. Hernandez; P. Herquet; H. Herr; T. L. Hessing; E. Higon; H. J. Hilke; T. S. Hill; S.-O. Holmgren; P. J. Holt; D. Holthuizen; M. Houlden; J. Hrubec; K. Huet; K. Hultqvist; P. Joannou; J. N. Jackson; R. Jacobsson; P. Jalocha; R. Janik; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; L. Jonsson; P. Jonsson; C. Joram; P. Juillot; M. Kaiser; G. Kalmus; F. Kapusta; M. Karlsson; E. Karvelas; S. Katsanevas; E. C. Katsoufis; R. Keranen; B. A. Khomenko; N. N. Khovanski; B. King; N. J. Kjaer; H. Klein; A. Klovning; P. Kluit; J. H. Koehne; B. Koene; P. Kokkinias; M. Koratzinos; V. Kostioukhine; C. Kourkoumelis; O. Kouznetsov; P.-H. Kramer; M. Krammer; C. Kreuter; J. Krolikowski; I. Kronkvist; Z. Krumstein; W. Krupinski; P. Kubinec; W. Kucewicz; K. Kurvinen; C. Lacasta; I. Laktineh; S. Lamblot; J. W. Lamsa; L. Lanceri; P. Langefeld; I. Last; J.-P. Laugier; R. Lauhakangas; G. Leder; F. Ledroit; V. Lefebure; C. K. Legan; R. Leitner; Y. Lemoigne; J. Lemonne; G. Lenzen; V. Lepeltier; T. Lesiak; D. Liko; R. Lindner; A. Lipniacka; I. Lippi; B. Loerstad; M. Lokajicek; J. G. Loken; J. M. Lopez; A. Lopez-Fernandez; M. A. Lopez Aguera; D. Loukas; P. Lutz; L. Lyons; J. MacNaughton; G. Maehlum; A. Maio; V. Malychev; F. Mandl; J. Marco; B. Marechal; M. Margoni; J.-C. Marin; C. Mariotti; A. Markou; T. Maron; C. Martinez-Rivero; F. Martinez-Vidal; S. Marti I Garcia; F. Matorras; C. Matteuzzi; G. Matthiae; M. Mazzucato; R. Mc Cubbin; R. Mc Kay; R. Mc Nulty; J. Medbo; C. Meroni; W. T. Meyer; M. Michelotto; E. Migliore; L. Mirabito; W. A. Mitaroff; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; L. M. Mundim; W. J. Murray; B. Muryn; G. Myatt; F. Naraghi; F. L. Navarria; S. Navas; P. Negri; S. Nemecek; W. Neumann; R. Nicolaidou; B. S. Nielsen; M. Nieuwenhuizen; V. Nikolaenko; P. Niss; A. Nomerotski; A. Normand; W. Oberschulte-Beckmann; V. Obraztsov; A. G. Olshevski; A. Onofre; R. Orava; K. Osterberg; A. Ouraou; P. Paganini; M. Paganoni; P. Pages; H. Palka; Th. D. Papadopoulou; L. Pape; C. Parkes; F. Parodi; A. Passeri; M. Pegoraro; L. Peralta; H. Pernegger; M. Pernicka; A. Perrotta; C. Petridou; A. Petrolini

1995-01-01

268

Lifetime Assessment for Thermal Barrier Coatings: Tests for Measuring Mixed Mode Delamination Toughness  

E-print Network

II conditions. I. Introduction A thermal barrier coating (TBC) is a miracle of materials engi the thermally grown oxide (TGO), and a porous ceramic topcoat which serves as the thermal insulation. DetailsLifetime Assessment for Thermal Barrier Coatings: Tests for Measuring Mixed Mode Delamination

Hutchinson, John W.

269

Precision Measurement of the Mass and Lifetime of the ?[? over b] Baryon  

E-print Network

We report on measurements of the mass and lifetime of the ?[- over b] baryon using about 1800 ?[- over b] decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0??fb[superscript ...

Aaij, R.

270

An Undergraduate Experiment on Nuclear Lifetime Measurement Using the Doppler Effect  

ERIC Educational Resources Information Center

While designed for a senior undergraduate laboratory, the experiment illustrates the principles involved in the various Doppler techniques currently used in nuclear lifetime studies and demonstrates the versatility of the Ge(Li) detector in applications other than direct energy or intensity measurement. (Author/TS)

Campbell, J. L.; And Others

1972-01-01

271

Hyperfine predissociation in the B state of iodine investigated through lifetime measurements of individual hyperfine sublevels  

E-print Network

347 Hyperfine predissociation in the B state of iodine investigated through lifetime measurements±5) s-½, pour le niveau 03C5 = 43 de l'état B0+u. Abstract. 2014 Iodine exhibits the phenomenon. In this respect, studies of predis- sociation phenomena are of special interest. The case of the iodine B state

Boyer, Edmond

272

Pressure Sensitive Paint Measurements on a Space Shuttle Model with the Luminescence Lifetime Technique  

Microsoft Academic Search

The luminescence lifetime technique was used to make pressure-sensitive paint (PSP) measurements on a 3% Space Shuttle model in the NASA Ames 9x7ft Supersonic Wind Tunnel. This work was done in support of the Space Shuttle \\

J. H. Bell; M. E. Sellers

2005-01-01

273

Measurement of the Masses and Lifetimes of B Hadrons at the Tevatron  

SciTech Connect

The latest results for the B Hadron sector at the Tevatron Collider are summarized. The properties of B hadrons can be precisely measured at the Tevatron. In particularly they will focus on the masses and lifetimes. The new Tevatron results for the CP violation in B Hadrons are also discussed.

Catastini, Pierluigi; /Pisa U. /INFN, Pisa

2006-05-01

274

Lifetime and Relative g Factor Measurements in 104,106,108Pd  

NASA Astrophysics Data System (ADS)

The lifetimes and the relative g factors of the first excited states in 104,106,108Pd are reported here. The first 2+1 state in these Pd isotopes were excited by inverse kinematics Coulomb excitation on a 24Mg target and the lifetime was measured by the Recoil Distance Doppler Shift with the New Yale Plunger Device combined with the SPEEDY array of Clover detectors. The results show the feasibility of the new method, which should be applicable to experiments with radioactive ion beams.

Ilie, G.; Werner, V.; Radeck, D.; Ahn, T.; Bettermann, L.; Casperson, R. J.; Chevrier, R.; Cooper, N. M.; Heinz, A.; Holland, E.; McCarthy, D.; Smith, M. K.; Terry, J. R.; Williams, E.; Beausang, C. W.; Bonniwell, T. C.; Pauertein, B.

2013-03-01

275

Apparatus and method for measuring fluorescence intensities at a plurality of wavelengths and lifetimes  

DOEpatents

Apparatus and method for measuring intensities at a plurality of wavelengths and lifetimes. A source of multiple-wavelength electromagnetic radiation is passed through a first interferometer modulated at a first frequency, the output thereof being directed into a sample to be investigated. The light emitted from the sample as a result of the interaction thereof with the excitation radiation is directed into a second interferometer modulated at a second frequency, and the output detected and analyzed. In this manner excitation, emission, and lifetime information may be obtained for a multiplicity of fluorochomes in the sample.

Buican, Tudor N. (Albuquerque, NM)

1993-01-01

276

Apparatus and method for measuring fluorescence intensities at a plurality of wavelengths and lifetimes  

DOEpatents

Apparatus and method is described for measuring intensities at a plurality of wavelengths and lifetimes. A source of multiple-wavelength electromagnetic radiation is passed through a first interferometer modulated at a first frequency, the output thereof being directed into a sample to be investigated. The light emitted from the sample as a result of the interaction thereof with the excitation radiation is directed into a second interferometer modulated at a second frequency, and the output detected and analyzed. In this manner excitation, emission, and lifetime information may be obtained for a multiplicity of fluorochromes in the sample.

Buican, T.N.

1993-05-04

277

Measurement of the B0S meson lifetime using semileptonic decays  

Microsoft Academic Search

The lifetime of the B0S meson is measured using the semileptonic decay B0S-->D-Sl+nuX. The data sample consists of about 110 pb-1 of pp¯ collisions at s=1.8 TeV collected by the CDF detector at Fermilab. Four different D-S decay modes are reconstructed resulting in approximately 600 D-Sl+ signal events. The B0S meson lifetime is determined to be tau(B0S)=(1.36+\\/-0.09+0.06-0.05) ps, where the

F. Abe; H. Akimoto; A. Akopian; M. G. Albrow; A. Amadon; S. R. Amendolia; D. Amidei; J. Antos; S. Aota; G. Apollinari; T. Arisawa; T. Asakawa; W. Ashmanskas; M. Atac; P. Azzi-Bacchetta; N. Bacchetta; S. Bagdasarov; M. W. Bailey; P. de Barbaro; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; M. Barone; G. Bauer; T. Baumann; F. Bedeschi; S. Behrends; S. Belforte; G. Bellettini; J. Bellinger; D. Benjamin; J. Bensinger; A. Beretvas; J. P. Berge; J. Berryhill; S. Bertolucci; S. Bettelli; B. Bevensee; A. Bhatti; K. Biery; C. Bigongiari; M. Binkley; D. Bisello; R. E. Blair; C. Blocker; S. Blusk; A. Bodek; W. Bokhari; G. Bolla; Y. Bonushkin; D. Bortoletto; J. Boudreau; L. Breccia; C. Bromberg; N. Bruner; R. Brunetti; E. Buckley-Geer; H. S. Budd; K. Burkett; G. Busetto; A. Byon-Wagner; K. L. Byrum; M. Campbell; A. Caner; W. Carithers; D. Carlsmith; J. Cassada; A. Castro; D. Cauz; A. Cerri; P. S. Chang; H. Y. Chao; J. Chapman; M.-T. Cheng; M. Chertok; G. Chiarelli; C. N. Chiou; F. Chlebana; L. Christofek; M. L. Chu; S. Cihangir; A. G. Clark; M. Cobal; E. Cocca; M. Contreras; J. Conway; J. Cooper; M. Cordelli; D. Costanzo; C. Couyoumtzelis; D. Cronin-Hennessy; R. Culbertson; D. Dagenhart; T. Daniels; F. Dejongh; S. dell'agnello; M. dell'orso; R. Demina; L. Demortier; M. Deninno; P. F. Derwent; T. Devlin; J. R. Dittmann; S. Donati; J. Done; T. Dorigo; N. Eddy; K. Einsweiler; J. E. Elias; R. Ely; E. Engels; W. Erdmann; D. Errede; S. Errede; Q. Fan; R. G. Feild; Z. Feng; C. Ferretti; I. Fiori; B. Flaugher; G. W. Foster; M. Franklin; J. Freeman; J. Friedman; Y. Fukui; S. Gadomski; S. Galeotti; M. Gallinaro; O. Ganel; M. Garcia-Sciveres; A. F. Garfinkel; C. Gay; S. Geer; D. W. Gerdes; P. Giannetti; N. Giokaris; P. Giromini; G. Giusti; M. Gold; A. Gordon; A. T. Goshaw; Y. Gotra; K. Goulianos; H. Grassmann; L. Groer; C. Grosso-Pilcher; G. Guillian; J. Guimaraes da Costa; R. S. Guo; C. Haber; E. Hafen; S. R. Hahn; T. Handa; R. Handler; F. Happacher; K. Hara; A. D. Hardman; R. M. Harris; F. Hartmann; J. Hauser; E. Hayashi; J. Heinrich; W. Hao; B. Hinrichsen; K. D. Hoffman; M. Hohlmann; C. Holck; R. Hollebeek; L. Holloway; Z. Huang; B. T. Huffman; R. Hughes; J. Huston; J. Huth; H. Ikeda; M. Incagli; J. Incandela; G. Introzzi; J. Iwai; Y. Iwata; E. James; H. Jensen; U. Joshi; E. Kajfasz; H. Kambara; T. Kamon; T. Kaneko; K. Karr; H. Kasha; Y. Kato; T. A. Keaffaber; K. Kelley; R. D. Kennedy; R. Kephart; D. Kestenbaum; D. Khazins; T. Kikuchi; B. J. Kim; H. S. Kim; S. H. Kim; Y. K. Kim; L. Kirsch; S. Klimenko; D. Knoblauch; P. Koehn; A. Köngeter; K. Kondo; J. Konigsberg; K. Kordas; A. Korytov; E. Kovacs; W. Kowald; J. Kroll; M. Kruse; S. E. Kuhlmann; E. Kuns; K. Kurino; T. Kuwabara; A. T. Laasanen; S. Lami; S. Lammel; J. I. Lamoureux; M. Lancaster; M. Lanzoni; G. Latino; T. Lecompte; S. Leone; J. D. Lewis; M. Lindgren; T. M. Liss; J. B. Liu; Y. C. Liu; N. Lockyer; O. Long; C. Loomis; M. Loreti; D. Lucchesi; P. Lukens; S. Lusin; J. Lys; K. Maeshima; P. Maksimovic; M. Mangano; M. Mariotti; J. P. Marriner; G. Martignon; A. Martin; J. A. Matthews; P. Mazzanti; K. McFarland; P. McIntyre; P. Melese; M. Menguzzato; A. Menzione; E. Meschi; S. Metzler; C. Miao; T. Miao; G. Michail; R. Miller; H. Minato; S. Miscetti; M. Mishina; S. Miyashita; N. Moggi; E. Moore; Y. Morita; A. Mukherjee; T. Muller; P. Murat; S. Murgia; M. Musy; H. Nakada; T. Nakaya; I. Nakano; C. Nelson; D. Neuberger; C. Newman-Holmes; C.-Y. P. Ngan; L. Nodulman; A. Nomerotski; S. H. Oh; T. Ohmoto; T. Ohsugi; R. Oishi; M. Okabe; T. Okusawa; J. Olsen; C. Pagliarone; R. Paoletti; V. Papadimitriou; S. P. Pappas; N. Parashar; A. Parri; J. Patrick; G. Pauletta; M. Paulini; A. Perazzo; L. Pescara; M. D. Peters; T. J. Phillips; G. Piacentino; M. Pillai; K. T. Pitts; R. Plunkett; A. Pompos; L. Pondrom; J. Proudfoot; F. Ptohos; G. Punzi; K. Ragan; D. Reher; M. Reischl; A. Ribon; F. Rimondi; L. Ristori; W. J. Robertson; T. Rodrigo; S. Rolli; L. Rosenson; R. Roser; T. Saab; W. K. Sakumoto; D. Saltzberg; A. Sansoni; L. Santi; H. Sato; P. Schlabach; E. E. Schmidt; M. P. Schmidt; A. Scott; A. Scribano; S. Segler; S. Seidel; Y. Seiya; F. Semeria; T. Shah; M. D. Shapiro; N. M. Shaw; P. F. Shepard; T. Shibayama; M. Shimojima; M. Shochet; J. Siegrist; A. Sill; P. Sinervo; P. Singh; K. Silwa; C. Smith; F. D. Snider; J. Spalding; T. Speer; P. Sphicas; F. Spinella; M. Spiropulu; L. Spiegel; L. Stanco; J. Steele; A. Stefanini; R. Ströhmer; Strologas J; F. Strumia; D. Stuart; K. Sumorok; J. Suzuki; T. Suzuki; T. Takahashi; T. Takano; R. Takashima; K. Takikawa; M. Tanaka; B. Tannenbaum; F. Tartarelli; W. Taylor; M. Tecchio; P. K. Teng; Y. Teramoto; K. Terashi; S. Tether; D. Theriot; T. L. Thomas; R. Thurman-Keup; M. Timko; P. Tipton; A. Titov; S. Tkaczyk; D. Toback; K. Tollefson; A. Tollestrup; H. Toyoda; W. Trischuk; J. F. de Troconiz; S. Truitt; J. Tseng; N. Turini; T. Uchida

1999-01-01

278

Evaluation of single-photon-counting measurements of excited-state lifetimes  

PubMed Central

An extremely short instrumental response function for a single-photon-counting system has been obtained by using a low-jitter photomultiplier tube, fast amplification of the single photoelectron pulse from this photomultiplier, a constant fraction discriminator with a wide bandwidth input, and a stable reference timing signal. This synchronously mode-locked laser system has been shown to be capable of measuring the fluorescence lifetimes of compounds from 66 psec to 4.5 nsec. The estimated error in these determinations is 6% or 10 psec, whichever is greater. This apparatus has proved itself to be superior to the previously used nitrogen flashlamp apparatus for the determination of subnanosecond lifetimes. The validity of using deconvolution to determine lifetimes shorter than the instrumental response function has been verified. PMID:16593174

Zimmerman, Howard E.; Penn, John H.; Carpenter, Clint W.

1982-01-01

279

Interpreting aerosol lifetimes using the GEOS-Chem model and constraints from radionuclide measurements  

NASA Astrophysics Data System (ADS)

Aerosol removal processes control global aerosol abundance, but the rate of that removal remains uncertain. A recent study of aerosol-bound radionuclide measurements after the Fukushima Dai-Ichi nuclear power plant accident documents 137Cs removal (e-folding) times of 10.0 to 13.9 days, suggesting that mean aerosol lifetimes in the range of 3-7 days in global models might be too short by a factor of two. In this study, we attribute this discrepancy to differences between the e-folding and mean aerosol lifetimes. We implement a~simulation of 137Cs and 133Xe into the GEOS-Chem chemical transport model and examine the removal rates for the Fukushima case. We find a~general consistency between modelled and measured e-folding times. The simulated 137Cs global burden e-folding time is about 14 days. However, the simulated mean lifetime of aerosol-bound 137Cs over a 6 month post-accident period is only 1.8 days. We find that the mean lifetime depends strongly on the removal rates in the first few days after emissions, before the aerosols leave the boundary layer and are transported to altitudes and latitudes where lifetimes with respect to wet removal are longer by a few orders of magnitude. We present sensitivity simulations that demonstrate the influence of differences in altitude and location of the radionuclides on the mean lifetime. Global mean lifetimes are shown to strongly depend on the altitude of injection. The global mean 137Cs lifetime is more than one order of magnitude greater for the injection at 7 km than into the boundary layer above the Fukushima site. Instantaneous removal rates are slower during the first few days after the emissions for a free tropospheric vs. boundary layer injection and this strongly controls the mean lifetimes. Global mean aerosol lifetimes for the GEOS-Chem model are 3-6 days, which is longer than for the 137Cs injected at the Fukushima site (likely due to precipitation shortly after Fukushima emissions), but about the same as the mean lifetime of 3.9 days for the 137Cs emissions injected with a uniform spread through the model's Northern Hemisphere boundary layer. Despite the reasonable global mean agreement of GEOS-Chem with measurement e-folding times, site by site comparisons yield differences of up to a factor of two, which suggest possible deficiencies in either the model transport, removal processes or the representation of 137Cs removal, particularly in the tropics and at high latitudes. There is an ongoing need to develop constraints on aerosol lifetimes, but these measurement-based constraints must be carefully interpreted given the sensitivity of mean and e-folding times to both mixing and removal processes.

Croft, B.; Pierce, J. R.; Martin, R. V.

2013-12-01

280

Measurement of the Lifetime Difference in the B0s System  

NASA Astrophysics Data System (ADS)

We present a study of the decay Bs0?J/??. We obtain the CP-odd fraction in the final state at time zero, R?=0.16±0.10(stat)±0.02(syst), the average lifetime of the (Bs0, Bmacr s0) system, ?¯(Bs0)=1.39-0.16+0.13(stat)-0.02+0.01(syst)ps, and the relative width difference between the heavy and light mass eigenstates, ??/?¯?(?L-?H)/?¯=0.24-0.38+0.28(stat)-0.04+0.03(syst). With the additional constraint from the world average of the Bs0 lifetime measurements using semileptonic decays, we find ?¯(Bs0)=1.39±0.06ps and ??/?¯=0.25-0.15+0.14. For the ratio of the Bs0 and B0 lifetimes we obtain (?¯(Bs0))/(?(B0))=0.91±0.09(stat)±0.003(syst).

Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S. H.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Anastasoaie, M.; Andeen, T.; Anderson, S.; Andrieu, B.; Arnoud, Y.; Arov, M.; Askew, A.; Åsman, B.; Assis Jesus, A. C. S.; Atramentov, O.; Autermann, C.; Avila, C.; Badaud, F.; Baden, A.; Bagby, L.; Baldin, B.; Balm, P. W.; Banerjee, P.; Banerjee, S.; Barberis, E.; Bargassa, P.; Baringer, P.; Barnes, C.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Bean, A.; Beauceron, S.; Begalli, M.; Begel, M.; Bellavance, A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Binder, M.; Biscarat, C.; Black, K. M.; Blackler, I.; Blazey, G.; Blekman, F.; Blessing, S.; Bloch, D.; Blumenschein, U.; Boehnlein, A.; Boeriu, O.; Bolton, T. A.; Borcherding, F.; Borissov, G.; Bos, K.; Bose, T.; Brandt, A.; Brock, R.; Brooijmans, G.; Bross, A.; Buchanan, N. J.; Buchholz, D.; Buehler, M.; Buescher, V.; Burdin, S.; Burke, S.; Burnett, T. H.; Busato, E.; Buszello, C. P.; Butler, J. M.; Cammin, J.; Caron, S.; Carvalho, W.; Casey, B. C. K.; Cason, N. M.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chapin, D.; Charles, F.; Cheu, E.; Cho, D. K.; Choi, S.; Choudhary, B.; Christiansen, T.; Christofek, L.; Claes, D.; Clément, B.; Clément, C.; Coadou, Y.; Cooke, M.; Cooper, W. E.; Coppage, D.; Corcoran, M.; Cothenet, A.; Cousinou, M.-C.; Cox, B.; Crépé-Renaudin, S.; Cutts, D.; da Motta, H.; Das, M.; Davies, B.; Davies, G.; Davis, G. A.; de, K.; de Jong, P.; de Jong, S. J.; de La Cruz-Burelo, E.; de Oliveira Martins, C.; Dean, S.; Degenhardt, J. D.; Déliot, F.; Demarteau, M.; Demina, R.; Demine, P.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Doidge, M.; Dong, H.; Doulas, S.; Dudko, L. V.; Duflot, L.; Dugad, S. R.; Duperrin, A.; Dyer, J.; Dyshkant, A.; Eads, M.; Edmunds, D.; Edwards, T.; Ellison, J.; Elmsheuser, J.; Elvira, V. D.; Eno, S.; Ermolov, P.; Eroshin, O. V.; Estrada, J.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Fast, J.; Fatakia, S. N.; Feligioni, L.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fleck, I.; Fortner, M.; Fox, H.; Fu, S.; Fuess, S.; Gadfort, T.; Galea, C. F.; Gallas, E.; Galyaev, E.; Garcia, C.; Garcia-Bellido, A.; Gardner, J.; Gavrilov, V.; Gay, A.; Gay, P.; Gelé, D.; Gelhaus, R.; Genser, K.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Ginther, G.; Golling, T.; Gollub, N.; Gómez, B.; Gounder, K.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Gris, Ph.; Grivaz, J.-F.; Groer, L.; Grünendahl, S.; Grünewald, M. W.; Gurzhiev, S. N.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hadley, N. J.; Hagopian, S.; Hall, I.; Hall, R. E.; Han, C.; Han, L.; Hanagaki, K.; Harder, K.; Harel, A.; Harrington, R.; Hauptman, J. M.; Hauser, R.; Hays, J.; Hebbeker, T.; Hedin, D.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hensel, C.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hong, S. J.; Hooper, R.; Houben, P.; Hu, Y.; Huang, J.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jain, V.; Jakobs, K.; Jenkins, A.; Jesik, R.; Johns, K.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Juste, A.; Käfer, D.; Kahn, S.; Kajfasz, E.; Kalinin, A. M.; Kalk, J.; Karmanov, D.; Kasper, J.; Katsanos, I.; Kau, D.; Kaur, R.; Kehoe, R.; Kermiche, S.; Kesisoglou, S.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. M.; Kim, H.; Kim, T. J.; Klima, B.; Kohli, J. M.; Konrath, J.-P.; Kopal, M.; Korablev, V. M.; Kotcher, J.; Kothari, B.; Koubarovsky, A.; Kozelov, A. V.; Kozminski, J.; Kryemadhi, A.; Krzywdzinski, S.; Kulik, Y.; Kumar, A.; Kunori, S.; Kupco, A.; Kur?a, T.; Kvita, J.; Lager, S.; Lahrichi, N.; Landsberg, G.; Lazoflores, J.; Le Bihan, A.-C.; Lebrun, P.; Lee, W. M.; Leflat, A.; Lehner, F.; Leonidopoulos, C.; Leveque, J.; Lewis, P.; Li, J.; Li, Q. Z.; Lima, J. G. R.; Lincoln, D.; Linn, S. L.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Lobo, L.; Lobodenko, A.; Lokajicek, M.; Lounis, A.; Love, P.; Lubatti, H. J.; Lueking, L.; Luo, L.; Lynker, M.; Lyon, A. L.; Maciel, A. K. A.; Madaras, R. J.; Mättig, P.; Magass, C.; Magerkurth, A.; Magnan, A.-M.; Makovec, N.; Mal, P. K.; Malbouisson, H. B.; Malik, S.; Malyshev, V. L.; Mao, H. S.; Maravin, Y.; Martens, M.; Mattingly, S. E. K.; Mayorov, A. A.; McCarthy, R.; McCroskey, R.; Meder, D.; Melnitchouk, A.; Mendes, A.; Mendoza, D.; Merkin, M.; Merritt, K. W.; Meyer, A.; Meyer, J.; Michaut, M.; Miettinen, H.; Mitrevski, J.; Molina, J.; Mondal, N. K.; Moore, R. W.; Moulik, T.; Muanza, G. S.; Mulders, M.; Mundim, L.; Mutaf, Y. D.

2005-10-01

281

Brain energy metabolism and dopaminergic function in Huntington's disease measured in vivo using positron emission tomography  

SciTech Connect

A 48-year-old man with typical Huntington's disease was investigated with computed tomography (CT) and positron emission tomography. Regional cerebral blood flow, oxygen extraction, oxygen and glucose utilization, L-Dopa uptake, and dopamine (D2) receptor binding were measured using several positron-labelled tracers. CT showed slight atrophy of the head of caudate but no cortical atrophy, although distinct frontal lobe dysfunction was present on psychometric testing. Oxygen and glucose metabolism and cerebral blood flow were decreased in the striata and to a lesser extent in frontal cortex. Cerebral blood flow was in the low normal range throughout the remainder of the brain. A normal metabolic ratio was found in all regions, since the changes in glucose utilization paralleled those in oxygen consumption. The capacity of the striatum to store dopamine as assessed by L-( YF)-fluorodopa uptake was normal, but dopamine (D2) receptor binding was decreased when compared to normal subjects.

Leenders, K.L.; Frackowiak, R.S.; Quinn, N.; Marsden, C.D.

1986-01-01

282

Measurement of the hadronic cross section in electron-positron annihilation  

SciTech Connect

This thesis describes the most precise measurement to date of the ratio R, the hadronic cross section in lowest order electron-positron annihilation to the cross section for muon pair production in lowest order electron-positron annihilation. This experiment is of interest because R is a fundamental parameter that tests in a model independent way the basic assumptions of strong interaction theories. According to the assumptions of one of these theories the value of R is determined simply from the electric charges, spin, and color assignments of the produced quark-pairs. The experiment was carried out with the MAgnetic Calorimeter using collisions of 14.5 GeV electrons and positrons at the 2200m circumference PEP storage ring at SLAC. The MAC detector is one of the best-suited collider detectors for measuring R due to its nearly complete coverage of the full angular range. The data for this experiment were accumulated between February 1982 and April 1983 corresponding to a total event sample of about 40,000 hadronic events. About 5% of the data were taken with 14 GeV beams and the rest of the data were taken with 14.5 GeV beams. A description of particle interactions and experimental considerations is given.

Clearwater, S.

1983-11-01

283

Precision lifetime measurements of exotic nuclei based on Doppler-shift techniques  

SciTech Connect

A recent progress in precision lifetime measurements of exotic nuclei at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University is presented. The Recoil Distance Doppler-shift (RDDS) technique has been applied to nuclear reactions involving intermediate-energy rare isotope (RI) beams, to determine absolute transition strengths between nuclear states model independently from level lifetimes of interest. As such an example, recent lifetime measurements of the first 2{sup +} states in the neutron-rich {sup 62,64,66}Fe isotopes at and around N=40 are introduced. The experiment was performed at the Coupled Cyclotron Facility at NSCL using a unique combination of several experimental instruments; the Segmented Germanium Array (SeGA), the plunger device, and the S800 spectrograph. The reduced E2 transition probabilities B(E2) are determined directly from the measured lifetimes. The observed trend of B(E2) clearly demonstrates that an enhanced collectivity persists in {sup 66}Fe despite the harmonic-oscillator magic number N=40. The present results are also discussed in comparison with the large-scale shell model calculations, pointing to a possible extension of the deformation region beyond N=40.

Iwasaki, Hironori [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States) and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan (United States)

2013-04-19

284

A method for measuring the energy spectrum of coincidence events in positron emission tomography.  

PubMed

Positron emission tomography (PET) system energy response is typically characterized in singles detection mode, yet there are situations in which the energy spectrum of coincidence events might be different than the spectrum measured in singles mode. Examples include imaging with isotopes that emit a prompt gamma in coincidence with a positron emission, imaging with low activity in a LSO/LYSO-based cameras, in which the intrinsic activity is significant, and in high scatter situations where the two 511 keV photons have different scattering probabilities (i.e. off-center line source). The ability to accurately measure the energy spectrum of coincidence events could be used for validating simulation models, optimizing energy discriminator levels and examining scatter models and corrections. For many PET systems operating in coincidence mode, the only method available for estimating the energy spectrum is to step the lower and upper level discriminators (LLD and ULD). Simple measurement techniques such as using a narrow sliding energy window or stepping only the LLD will not yield a spectrum of coincidence events that is accurate for cases where there are different energy components contributing to the spectrum. In this work we propose a new method of measuring the energy spectrum of coincidence events in PET based on a linear combination of two sets of coincident count measurements: one made by stepping the LLD and one made by stepping the ULD. The method was tested using both Monte Carlo simulations of a Siemens microPET R4 camera and measured data acquired on a Siemens Inveon PET camera. The results show that our energy spectrum calculation method accurately measures the coincident energy spectra for cases including the beta/gamma spectrum of the (176)Lu intrinsic activity present in the LSO scintillator crystals, a (68)Ge source and an (124)I source (in which there are prompt gamma-rays emitted together with the positron). PMID:20023324

Goertzen, Andrew L; Stout, David B; Thompson, Christopher J

2010-01-21

285

A method for measuring the energy spectrum of coincidence events in positron emission tomography  

PubMed Central

Positron emission tomography (PET) system energy response is typically characterized in singles detection mode, yet there are situations in which the energy spectrum of coincidence events might be different than the spectrum measured in singles mode. Examples include imaging with isotopes that emit a prompt gamma in coincidence with a positron emission, imaging with low activity in a LSO/LYSO-based cameras, in which the intrinsic activity is significant, and in high scatter situations where the two 511 keV photons have different scattering probabilities (i.e. off-center line source). The ability to accurately measure the energy spectrum of coincidence events could be used for validating simulation models, optimizing energy discriminator levels and examining scatter models and corrections. For many PET systems operating in coincidence mode, the only method available for estimating the energy spectrum is to step the lower and upper level discriminators (LLD and ULD). Simple measurement techniques such as using a narrow sliding energy window or stepping only the LLD will not yield a spectrum of coincidence events that is accurate for cases where there are different energy components contributing to the spectrum. In this work we propose a new method of measuring the energy spectrum of coincidence events in PET based on a linear combination of two sets of coincident count measurements: one made by stepping the LLD and one made by stepping the ULD. The method was tested using both Monte Carlo simulations of a Siemens microPET R4 camera and measured data acquired on a Siemens Inveon PET camera. The results show that our energy spectrum calculation method accurately measures the coincident energy spectra for cases including the beta/gamma spectrum of the 176Lu intrinsic activity present in the LSO scintillator crystals, a 68Ge source and an 124I source (in which there are prompt ?-rays emitted together with the positron). PMID:20023324

Stout, David B; Thompson, Christopher J

2010-01-01

286

Measurement of lifetimes and tensor polarizabilities of odd parity states of Sm I  

SciTech Connect

A systematic measurement of the lifetimes and tensor polarizabilities of the lowest-lying odd parity levels of Sm I was performed. The lifetimes were measured by detecting time-resolved fluorescence following pulsed laser excitation of atoms in an atomic beam; polarizabilities were measured employing the method of Stark-induced quantum beats. An analysis of the data is undertaken to find the best even parity candidate states for an atomic electric dipole moment (EDM) measurement. A term reassignment of several odd parity states is discussed. For the most favorable candidate state (7G1), the electron EDM enhancement factor is evaluated to be potentially as large as {approximately}10{sup 4}. Critical analysis of the present data along with earlier results in Sm shows the necessity of a term reassignment for several odd parity states. This term reassignment is also used in an estimate of the parity nonconserving 7F0 {r{underscore}arrow} 7G1 amplitude.

Rochester, S.

1999-01-01

287

Positron annihilation spectroscopy to study nanoprecipitations in aluminum alloys  

NASA Astrophysics Data System (ADS)

Positron Annihilation Spectroscopy has been used to study the microstructure in aluminum alloy AA7075-T6 after RRA (retrogression and re-aging) heat treatment. Nano-precipitates act as traps for thermalised positrons. The measured positron lifetime is sensitive to the local electron density at the annihilation site while the Doppler broadening of the annihilation line is sensitive to the chemical environment of the annihilation site. The combination of both methods was used to study changes of nano-precipitates, during the Retrogression and Re-aging (RRA) process. Results are compared to previous published isochronal annealing experiments of an Al Cu model alloy.

Meyendorf, Norbert; Dlubek, Gunter; Surkov, Alexander

2004-07-01

288

Precision measurement of the metastable 3 P2 lifetime of neon  

E-print Network

Precision measurement of the metastable 3 P2 lifetime of neon Martin Zinner, Peter Spoden, Tobias of the metastable 3 P2 state of neon has been determined as 14.73(14) s decay rate 0.067 90(64) s 1 ] by measuring of the metastable 3 P2 state 1 of neon with sufficient precision. A selection of research activities profiting from

Birkl, Gerhard

289

Measurement of the average lifetime of b-hadrons in Z decays  

Microsoft Academic Search

We present a measurement of the average b-hadron lifetime ${\\\\rm \\\\tau_b}$ at the $\\\\mathrm{e^+e^-} \\\\, $ collider LEP. Using hadronic Z decays collected in the period from 1991 to 1994, two independent analyses have been performed. In the first one, the b-decay position is reconstructed as a secondary vertex of hadronic b-decay particles. The second analysis is an updated measurement

M Acciarri; O Adriani; M Aguilar-Benítez; S P Ahlen; J Alcaraz; G Alemanni; James V Allaby; A Aloisio; G Alverson; M G Alviggi; G Ambrosi; H Anderhub; V P Andreev; T Angelescu; F Anselmo; A Arefev; T Azemoon; T Aziz; P Bagnaia; L Baksay; R C Ball; S Banerjee; K Banicz; A Barczyk; R Barillère; L Barone; P Bartalini; A Baschirotto; M Basile; R Battiston; A Bay; F Becattini; U Becker; F Behner; J Berdugo; P Berges; B Bertucci; B L Betev; S Bhattacharya; M Biasini; A Biland; G M Bilei; J J Blaising; S C Blyth; Gerjan J Bobbink; R K Böck; A Böhm; L Boldizsar; B Borgia; D Bourilkov; Maurice Bourquin; D Boutigny; S Braccini; J G Branson; V Brigljevic; I C Brock; A Buffini; A Buijs; J D Burger; W J Burger; J K Busenitz; X D Cai; M Campanelli; M Capell; G Cara Romeo; G Carlino; A M Cartacci; J Casaus; G Castellini; F Cavallari; N Cavallo; C Cecchi; M Cerrada-Canales; F Cesaroni; M Chamizo-Llatas; Y H Chang; U K Chaturvedi; S V Chekanov; M Chemarin; A Chen; G Chen; H F Chen; H S Chen; M Chen; G Chiefari; C Y Chien; Luisa Cifarelli; F Cindolo; C Civinini; I Clare; R Clare; H O Cohn; G Coignet; A P Colijn; N Colino; S Costantini; F Cotorobai; B de la Cruz; Akos Csilling; T S Dai; R D'Alessandro; R De Asmundis; A Degré; K Deiters; P Denes; F De Notaristefani; Daryl DiBitonto; M Diemoz; D N Van Dierendonck; F Di Lodovico; C Dionisi; Michael Dittmar; A Dominguez; A Doria; M T Dova; E Drago; D Duchesneau; P Duinker; I Durán; S Dutta; S Easo; Yu V Efremenko; H El-Mamouni; A Engler; F J Eppling; F C Erné; J P Ernenwein; Pierre Extermann; M Fabre; R Faccini; S Falciano; A Favara; J Fay; O Fedin; Marta Felcini; B Fenyi; T Ferguson; F Ferroni; H S Fesefeldt; E Fiandrini; J H Field; Frank Filthaut; P H Fisher; I Fisk; G Forconi; L Fredj; Klaus Freudenreich; C Furetta; Yu Galaktionov; S N Ganguli; P García-Abia; S S Gau; S Gentile; J Gerald; N Gheordanescu; S Giagu; S Goldfarb; J Goldstein; Z F Gong; Andreas Gougas; Giorgio Gratta; M W Grünewald; V K Gupta; A Gurtu; L J Gutay; B Hartmann; A Hasan; D Hatzifotiadou; T Hebbeker; A Hervé; W C Van Hoek; H Hofer; S J Hong; H Hoorani; S R Hou; G Hu; Vincenzo Innocente; K Jenkes; B N Jin; L W Jones; P de Jong; I Josa-Mutuberria; A Kasser; R A Khan; D Kamrad; Yu A Kamyshkov; J S Kapustinsky; Yu Karyotakis; M Kaur; M N Kienzle-Focacci; D Kim; J K Kim; S C Kim; Y G Kim; W W Kinnison; A Kirkby; D Kirkby; Jasper Kirkby; D Kiss; E W Kittel; A Klimentov; A C König; A Kopp; I Korolko; V F Koutsenko; R W Krämer; W Krenz; A Kunin; P E Lacentre; P Ladrón de Guevara; G Landi; C Lapoint; K M Lassila-Perini; P Laurikainen; M Lebeau; A Lebedev; P Lebrun; P Lecomte; P Lecoq; P Le Coultre; H J Lee; C Leggett; J M Le Goff; R Leiste; E Leonardi; P M Levchenko; Li Chuan; C H Lin; W T Lin; Frank L Linde; L Lista; Z A Liu; W Lohmann; E Longo; W Lu; Y S Lü; K Lübelsmeyer; C Luci; D Luckey; L Luminari; W Lustermann; Ma Wen Gan; M Maity; G Majumder; L Malgeri; A Malinin; C Maña; D J J Mangeol; S Mangla; P A Marchesini; A Marin; J P Martin; F Marzano; G G G Massaro; D McNally; S Mele; L Merola; M Meschini; W J Metzger; M Von der Mey; Y Mi; A Mihul; A J W Van Mil; H Milcent; G Mirabelli; J Mnich; P Molnár; B Monteleoni; R Moore; S Morganti; T Moulik; R Mount; F Muheim; A J M Muijs; S Nahn; M Napolitano; F Nessi-Tedaldi; H Newman; T Niessen; A Nippe; A Nisati; H Nowak; Yu D Oh; H Opitz; G Organtini; R Ostonen; C Palomares; D Pandoulas; S Paoletti; P Paolucci; H K Park; I H Park; G Pascale; G Passaleva; S Patricelli; T Paul; M Pauluzzi; C Paus; Felicitas Pauss; D Peach; Y J Pei; S Pensotti; D Perret-Gallix; B Petersen; S Petrak; A Pevsner; D Piccolo; M Pieri; P A Piroué; E Pistolesi; V Plyaskin; M Pohl; V Pozhidaev; H Postema; N Produit; D Prokofev; D O Prokofiev; G Rahal-Callot; N Raja; P G Rancoita; M Rattaggi; G Raven; P A Razis; K Read; D Ren; M Rescigno; S Reucroft; T Van Rhee; S Riemann; K Riles; O Rind; A Robohm; J Rodin; B P Roe; L Romero; S Rosier-Lees; P Rosselet; W Van Rossum; S Roth; Juan Antonio Rubio; D Ruschmeier; H Rykaczewski; J Salicio; E Sánchez; M P Sanders; M E Sarakinos; S Sarkar; G Sauvage; C Schäfer; V Shchegelskii; S Schmidt-Kärst; D Schmitz; M Schneegans; N Scholz; Herwig Franz Schopper; D J Schotanus; J Schwenke; G Schwering; C Sciacca; D Sciarrino; L Servoli; S Shevchenko; N Shivarov; V Shoutko; J Shukla; E Shumilov; A V Shvorob; T Siedenburg; D Son; V Soulimov; B Smith; P Spillantini; M Steuer; D P Stickland; H Stone; B Stoyanov; A Strässner; K Strauch; K Sudhakar; G G Sultanov; L Z Sun; G F Susinno; H Suter; J D Swain; X W Tang; Ludwig Tauscher; L Taylor; Samuel C C Ting; S M Ting; S C Tonwar; J Tóth; C Tully; H Tuchscherer; K L Tung; Y Uchida; J Ulbricht; U Uwer; E Valente; R T Van de Walle; G Vesztergombi; I Vetlitskii; Gert M Viertel; M Vivargent; R Völkert; H Vogel; H Vogt; I Vorobev; A A Vorobyov; A Vorvolakos; M Wadhwa; W Wallraff; J C Wang; X L Wang; Z M Wang; A Weber; S X Wu

1997-01-01

290

Measurement of the B and B¯0 meson lifetimes using semileptonic decays  

Microsoft Academic Search

The lifetimes of the B- and B¯0 mesons are measured using the partially reconstructed semileptonic decays B¯-->Dl-nu¯X, where D is either a D0 or D*+ meson. The data were collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995 and correspond to about 110 pb-1 of p¯p collisions at s=1.8 TeV. We measure decay lengths and extract the

F. Abe; H. Akimoto; A. Akopian; M. G. Albrow; A. Amadon; S. R. Amendolia; D. Amidei; J. Antos; S. Aota; G. Apollinari; T. Arisawa; T. Asakawa; W. Ashmanskas; M. Atac; P. Azzi-Bacchetta; N. Bacchetta; S. Bagdasarov; M. W. Bailey; P. de Barbaro; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; M. Barone; G. Bauer; T. Baumann; F. Bedeschi; S. Behrends; S. Belforte; G. Bellettini; J. Bellinger; D. Benjamin; J. Bensinger; A. Beretvas; J. P. Berge; J. Berryhill; S. Bertolucci; S. Bettelli; B. Bevensee; A. Bhatti; K. Biery; C. Bigongiari; M. Binkley; D. Bisello; R. E. Blair; C. Blocker; S. Blusk; A. Bodek; W. Bokhari; G. Bolla; Y. Bonushkin; D. Bortoletto; J. Boudreau; L. Breccia; C. Bromberg; N. Bruner; R. Brunetti; E. Buckley-Geer; H. S. Budd; K. Burkett; G. Busetto; A. Byon-Wagner; K. L. Byrum; M. Campbell; A. Caner; W. Carithers; D. Carlsmith; J. Cassada; A. Castro; D. Cauz; A. Cerri; P. S. Chang; H. Y. Chao; J. Chapman; M.-T. Cheng; M. Chertok; G. Chiarelli; C. N. Chiou; F. Chlebana; L. Christofek; M. L. Chu; S. Cihangir; A. G. Clark; M. Cobal; E. Cocca; M. Contreras; J. Conway; J. Cooper; M. Cordelli; D. Costanzo; C. Couyoumtzelis; D. Cronin-Hennessy; R. Culbertson; D. Dagenhart; T. Daniels; F. Dejongh; S. dell'agnello; M. dell'orso; R. Demina; L. Demortier; M. Deninno; P. F. Derwent; T. Devlin; J. R. Dittmann; S. Donati; J. Done; T. Dorigo; N. Eddy; K. Einsweiler; J. E. Elias; R. Ely; E. Engels; W. Erdmann; D. Errede; S. Errede; Q. Fan; R. G. Feild; Z. Feng; C. Ferretti; I. Fiori; B. Flaugher; G. W. Foster; M. Franklin; J. Freeman; J. Friedman; Y. Fukui; S. Gadomski; S. Galeotti; M. Gallinaro; O. Ganel; M. Garcia-Sciveres; A. F. Garfinkel; C. Gay; S. Geer; D. W. Gerdes; P. Giannetti; N. Giokaris; P. Giromini; G. Giusti; M. Gold; A. Gordon; A. T. Goshaw; Y. Gotra; K. Goulianos; H. Grassmann; L. Groer; C. Grosso-Pilcher; G. Guillian; J. Guimaraes da Costa; R. S. Guo; C. Haber; E. Hafen; S. R. Hahn; T. Handa; R. Handler; F. Happacher; K. Hara; A. D. Hardman; R. M. Harris; F. Hartmann; J. Hauser; E. Hayashi; J. Heinrich; W. Hao; B. Hinrichsen; K. D. Hoffman; M. Hohlmann; C. Holck; R. Hollebeek; L. Holloway; Z. Huang; B. T. Huffman; R. Hughes; J. Huston; J. Huth; H. Ikeda; M. Incagli; J. Incandela; G. Introzzi; J. Iwai; Y. Iwata; E. James; H. Jensen; U. Joshi; E. Kajfasz; H. Kambara; T. Kamon; T. Kaneko; K. Karr; H. Kasha; Y. Kato; T. A. Keaffaber; K. Kelley; R. D. Kennedy; R. Kephart; D. Kestenbaum; D. Khazins; T. Kikuchi; B. J. Kim; H. S. Kim; S. H. Kim; Y. K. Kim; L. Kirsch; S. Klimenko; D. Knoblauch; P. Koehn; A. Köngeter; K. Kondo; J. Konigsberg; K. Kordas; A. Korytov; E. Kovacs; W. Kowald; J. Kroll; M. Kruse; S. E. Kuhlmann; E. Kuns; K. Kurino; T. Kuwabara; A. T. Laasanen; S. Lami; S. Lammel; J. I. Lamoureux; M. Lancaster; M. Lanzoni; G. Latino; T. Lecompte; S. Leone; J. D. Lewis; P. Limon; M. Lindgren; T. M. Liss; J. B. Liu; Y. C. Liu; N. Lockyer; O. Long; C. Loomis; M. Loreti; D. Lucchesi; P. Lukens; S. Lusin; J. Lys; K. Maeshima; P. Maksimovic; M. Mangano; M. Mariotti; J. P. Marriner; G. Martignon; A. Martin; J. A. Matthews; P. Mazzanti; P. McIntyre; P. Melese; M. Menguzzato; A. Menzione; E. Meschi; S. Metzler; C. Miao; T. Miao; G. Michail; R. Miller; H. Minato; S. Miscetti; M. Mishina; S. Miyashita; N. Moggi; E. Moore; Y. Morita; A. Mukherjee; T. Muller; P. Murat; S. Murgia; M. Musy; H. Nakada; I. Nakano; C. Nelson; D. Neuberger; C. Newman-Holmes; C.-Y. P. Ngan; L. Nodulman; A. Nomerotski; S. H. Oh; T. Ohmoto; T. Ohsugi; R. Oishi; M. Okabe; T. Okusawa; J. Olsen; C. Pagliarone; R. Paoletti; V. Papadimitriou; S. P. Pappas; N. Parashar; A. Parri; J. Patrick; G. Pauletta; M. Paulini; A. Perazzo; L. Pescara; M. D. Peters; T. J. Phillips; G. Piacentino; M. Pillai; K. T. Pitts; R. Plunkett; A. Pompos; L. Pondrom; J. Proudfoot; F. Ptohos; G. Punzi; K. Ragan; D. Reher; M. Reischl; A. Ribon; F. Rimondi; L. Ristori; W. J. Robertson; T. Rodrigo; S. Rolli; L. Rosenson; R. Roser; T. Saab; W. K. Sakumoto; D. Saltzberg; A. Sansoni; L. Santi; H. Sato; P. Schlabach; E. E. Schmidt; M. P. Schmidt; A. Scott; A. Scribano; S. Segler; S. Seidel; Y. Seiya; F. Semeria; T. Shah; M. D. Shapiro; N. M. Shaw; P. F. Shepard; T. Shibayama; M. Shimojima; M. Shochet; J. Siegrist; A. Sill; P. Sinervo; P. Singh; K. Sliwa; C. Smith; F. D. Snider; J. Spalding; T. Speer; P. Sphicas; F. Spinella; M. Spiropulu; L. Spiegel; L. Stanco; J. Steele; A. Stefanini; R. Ströhmer; J. Strologas; F. Strumia; D. Stuart; K. Sumorok; J. Suzuki; T. Suzuki; T. Takahashi; T. Takano; R. Takashima; K. Takikawa; M. Tanaka; B. Tannenbaum; F. Tartarelli; W. Taylor; M. Tecchio; P. K. Teng; Y. Teramoto; K. Terashi; S. Tether; D. Theriot; T. L. Thomas; R. Thurman-Keup; M. Timko; P. Tipton; A. Titov; S. Tkaczyk; D. Toback; K. Tollefson; A. Tollestrup; H. Toyoda; W. Trischuk; J. F. de Troconiz; S. Truitt; J. Tseng; N. Turini; T. Uchida; F. Ukegawa; J. Valls

1998-01-01

291

Measurement of the B and B¯ 0 Meson Lifetimes Using Semileptonic Decays  

Microsoft Academic Search

The lifetimes of the B- and B¯ 0 mesons are measured using the partially reconstructed semileptonic decays B¯-->Dl-nu¯X, where D is either a D0 or D*+ meson. The data were collected by the CDF detector at the Fermilab Tevatron collider during 1992-1993 and correspond to 19.3 pb-1 of p¯p collisions at s = 1.8 TeV. We measure the decay length

F. Abe; H. Akimoto; A. Akopian; M. G. Albrow; S. R. Amendolia; D. Amidei; J. Antos; C. Anway-Wiese; S. Aota; G. Apollinari; T. Asakawa; W. Ashmanskas; M. Atac; F. Azfar; P. Azzi-Bacchetta; N. Bacchetta; W. Badgett; S. Bagdasarov; M. W. Bailey; J. Bao; P. de Barbaro; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; E. Barzi; G. Bauer; T. Baumann; F. Bedeschi; S. Behrends; S. Belforte; G. Bellettini; J. Bellinger; D. Benjamin; J. Benlloch; J. Bensinger; D. Benton; A. Beretvas; J. P. Berge; J. Berryhill; S. Bertolucci; A. Bhatti; K. Biery; M. Binkley; D. Bisello; R. E. Blair; C. Blocker; A. Bodek; W. Bokhari; V. Bolognesi; D. Bortoletto; J. Boudreau; L. Breccia; C. Bromberg; N. Bruner; E. Buckley-Geer; H. S. Budd; K. Burkett; G. Busetto; A. Byon-Wagner; K. L. Byrum; J. Cammerata; C. Campagnari; M. Campbell; A. Caner; W. Carithers; D. Carlsmith; A. Castro; D. Cauz; Y. Cen; F. Cervelli; P. Auchincloss; H. Y. Chao; J. Chapman; M.-T. Cheng; G. Chiarelli; T. Chikamatsu; C. N. Chiou; L. Christofek; S. Cihangir; A. G. Clark; M. Cobal; M. Contreras; J. Conway; J. Cooper; M. Cordelli; C. Couyoumtzelis; D. Crane; D. Cronin-Hennessy; R. Culbertson; J. D. Cunningham; T. Daniels; F. Dejongh; S. Delchamps; S. dell'Agnello; M. dell'Orso; L. Demortier; B. Denby; M. Deninno; P. F. Derwent; T. Devlin; J. R. Dittmann; S. Donati; J. Done; T. Dorigo; A. Dunn; N. Eddy; K. Einsweiler; J. E. Elias; R. Ely; E. Engels Jr.; D. Errede; S. Errede; Q. Fan; I. Fiori; B. Flaugher; G. W. Foster; M. Franklin; M. Frautschi; J. Freeman; J. Friedman; T. A. Fuess; Y. Fukui; S. Funaki; G. Gagliardi; S. Galeotti; M. Gallinaro; M. Garcia-Sciveres; A. F. Garfinkel; C. Gay; S. Geer; D. W. Gerdes; P. Giannetti; N. Giokaris; P. Giromini; L. Gladney; D. Glenzinski; M. Gold; J. Gonzalez; A. Gordon; A. T. Goshaw; K. Goulianos; H. Grassmann; L. Groer; C. Grosso-Pilcher; G. Guillian; R. S. Guo; C. Haber; E. Hafen; S. R. Hahn; R. Handler; R. M. Hans; K. Hara; A. D. Hardman; B. Harral; R. M. Harris; S. A. Hauger; J. Hauser; C. Hawk; E. Hayashi; J. Heinrich; K. D. Hoffman; M. Hohlmann; C. Holck; R. Hollebeek; L. Holloway; A. Hölscher; S. Hong; G. Houk; P. Hu; B. T. Huffman; R. Hughes; J. Huston; J. Huth; J. Hylen; H. Ikeda; M. Incagli; J. Incandela; G. Introzzi; J. Iwai; Y. Iwata; H. Jensen; U. Joshi; R. W. Kadel; E. Kajfasz; T. Kamon; T. Kaneko; K. Karr; H. Kasha; Y. Kato; T. A. Keaffaber; L. Keeble; K. Kelley; R. D. Kennedy; R. Kephart; P. Kesten; D. Kestenbaum; R. M. Keup; H. Keutelian; F. Keyvan; B. Kharadia; B. J. Kim; D. H. Kim; H. S. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; L. Kirsch; P. Koehn; K. Kondo; J. Konigsberg; S. Kopp; K. Kordas; W. Koska; E. Kovacs; W. Kowald; M. Krasberg; J. Kroll; M. Kruse; T. Kuwabara; S. E. Kuhlmann; E. Kuns; A. T. Laasanen; N. Labanca; S. Lammel; J. I. Lamoureux; T. Lecompte; S. Leone; J. D. Lewis; P. Limon; M. Lindgren; T. M. Liss; N. Lockyer; O. Long; C. Loomis; M. Loreti; J. Lu; D. Lucchesi; P. Lukens; S. Lusin; J. Lys; K. Maeshima; A. Maghakian; P. Maksimovic; M. Mangano; J. Mansour; M. Mariotti; J. P. Marriner; A. Martin; J. A. Matthews; R. Mattingly; P. McIntyre; P. Melese; A. Menzione; E. Meschi; S. Metzler; C. Miao; G. Michail; R. Miller; H. Minato; S. Miscetti; M. Mishina; H. Mitsushio; T. Miyamoto; S. Miyashita; Y. Morita; J. Mueller; A. Mukherjee; T. Muller; P. Murat; H. Nakada; I. Nakano; C. Nelson; D. Neuberger; C. Newman-Holmes; M. Ninomiya; L. Nodulman; S. H. Oh; K. E. Ohl; T. Ohmoto; T. Ohsugi; R. Oishi; M. Okabe; T. Okusawa; R. Oliver; J. Olsen; C. Pagliarone; R. Paoletti; V. Papadimitriou; S. P. Pappas; A. Parri; J. Patrick; G. Pauletta; M. Paulini; A. Perazzo; L. Pescara; M. D. Peters; T. J. Phillips; G. Piacentino; M. Pillai; K. T. Pitts; R. Plunkett; L. Pondrom; J. Proudfoot; F. Ptohos; G. Punzi; K. Ragan; A. Ribon; F. Rimondi; L. Ristori; W. J. Robertson; T. Rodrigo; S. Rolli; J. Romano; L. Rosenson; R. Roser; W. K. Sakumoto; D. Saltzberg; A. Sansoni; L. Santi; H. Sato; V. Scarpine; P. Schlabach; E. E. Schmidt; M. P. Schmidt; A. Scribano; S. Segler; S. Seidel; Y. Seiya; G. Sganos; A. Sgolacchia; M. D. Shapiro; N. M. Shaw; Q. Shen; P. F. Shepard; M. Shimojima; M. Shochet; J. Siegrist; A. Sill; P. Sinervo; P. Singh; J. Skarha; K. Sliwa; F. D. Snider; T. Song; J. Spalding; P. Sphicas; F. Spinella; M. Spiropulu; L. Spiegel; L. Stanco; J. Steele; A. Stefanini; K. Strahl; J. Strait; R. Ströhmer; D. Stuart; G. Sullivan; A. Soumarokov; K. Sumorok; J. Suzuki; T. Takada; T. Takahashi; T. Takano; K. Takikawa; N. Tamura; F. Tartarelli; W. Taylor; P. K. Teng; Y. Teramoto; S. Tether; D. Theriot; T. L. Thomas; R. Thun; M. Timko; P. Tipton; A. Titov; S. Tkaczyk; D. Toback; K. Tollefson; A. Tollestrup; J. Tonnison; J. F. de Troconiz; S. Truitt; J. Tseng; N. Turini; T. Uchida; N. Uemura; F. Ukegawa; G. Unal; S. C. van den Brink; S. Vejcik III; G. Velev; R. Vidal; M. Vondracek; D. Vucinic; R. G. Wagner

1996-01-01

292

Positron-annihilation measurements of vacancy formation in Ni and Ni(Ge)  

SciTech Connect

Vacancy formation in Ni and in dilute Ni(Ge) alloys was studied under thermal equilibrium conditions using positron-annihilation Doppler broadening. A monovacancy formation enthalpy of 1.8 +- 0.1 eV was determined for pure Ni; combining this result with that from previous tracer self-diffusion measurements, a monovacancy migration enthalpy of 1.1 +- 0.1 eV was also deduced. Analysis of the vacancy formation measurements in Ni(0.3 at.% Ge) and Ni(1 at.% Ge) yielded a value for the vacancy-Ge binding enthalpy of 0.20 +- 0.04 eV.

Smedskjaer, L.C.; Fluss, M.J.; Legnini, D.G.; Chason, M.K.; Siegel, R.W.

1982-03-01

293

Temperature dependent carrier lifetime measurements of InAs/InAsSb T2SLs  

NASA Astrophysics Data System (ADS)

Temperature dependent measurements of carrier recombination rates using a time-resolved pump-probe technique are reported for mid-wave infrared InAs/InAsSb type-2 superlattices (T2SLs). By engineering the layer widths and alloy compositions a 16 K band-gap of ~235 +/- 10meV was achieved for four doped and five undoped T2SLs. Carrier lifetimes were determined by fitting lifetime models of Shockley-Read-Hall (SRH), radiative, and Auger recombination processes simultaneously to the temperature and excess carrier density dependent data. The contribution of each recombination process at a given temperature is identified and the total lifetime is determined over a range of excess carrier densities. The minority carrier and Auger lifetimes were observed to increase with increasing antimony content and decreasing layer thickness for the undoped T2SLs. It is hypothesized that a reduction in SRH recombination centers or a shift in the SRH defect energy relative to the T2SL band edges is the cause of this increase in the SRH minority carrier lifetime. The lower Auger coefficients are attributed to a reduced number of final Auger states in the SL samples with greater antimony content. An Auger limited minority carrier lifetime is observed for the doped T2SLs, and it is found to be a factor of ten shorter than for undoped T2SLs. The Auger rates for all the InAs/InAsSb T2SLs were significantly larger than those previously reported for InAs/GaSb T2SLs.

Aytac, Y.; Olson, B. V.; Kim, J. K.; Shaner, E. A.; Hawkins, S. D.; Klem, J. F.; Flatté, M. E.; Boggess, T. F.

2015-01-01

294

Perspectives for TeV positron measurements with the PEBS Experiment  

NASA Astrophysics Data System (ADS)

Numerous astrophysical observations have produced an overwhelming evidence for the existence of dark matter in the universe. But till today, we have not understood its nature. Precision mea-surements of primary cosmic rays could provide crucial information to answer this fundamental question and could establish the missing link between collider experiments and cosmology. Pre-vious experiments reported tantalizing features in both the electron and positron spectrum but were not optimized for those measurements. This Positron-Electron-Balloon born Spectrometer (PEBS) therefore seeks to establish a new suborbital program with a goal to provide essentially background-free measurements of primary electrons and positrons in cosmic rays up to TeV energies. The PEBS detector would consist of a magnet, a transition radiation detector, a time of flight system, a novel high resolution scintillating fiber tracker and an electromagnetic calorimeter. The magnetic spectrometer has a geometrical acceptance for electrons of 1300 cm2 sr. One key element for a new generation of large area balloon experiments to measure charged cosmic rays is the capability of precision tracking of charged particles over large areas. We have therefore developed a novel modular high-resolution charged-particle tracking detector using round, scintillating fibers of 0.250 mm diameter and linear silicon photomultiplier arrays for readout. In a CERN beam line we have measured in 2009 a single point resolution of 0.05 mm for these devices. Different to space based experiments, balloon born experiments are more flexible as they can be realized on much shorter time scales and with less than 1 percent of the cost. The PEBS spectrometer is based on a modular detector concept such that it can be reused for several flights with continuous optimization of the scientific program. Detector concepts, test beam results and the scientific program will be presented.

Schael, Stefan

295

Atmospheric lifetime of caesium-137 as an estimate of aerosol lifetime -quantified from global measurements in the months after the Fukushima Dai-ichi nuclear accident  

NASA Astrophysics Data System (ADS)

Radionuclides like caesium-137 (137Cs) can be emitted to the atmosphere in great quantities during nuclear accidents and are of significant health impact. A global set of radionuclide measurements collected over several months after the accidental release from the Fukushima Dai-ichi nuclear power plant in March 2011 has been used to estimate the atmospheric lifetime of 137Cs. Lifetime is here defined as the e-folding time scale (the time interval in which the exponential decay of the 137Cs quantity has decreased by factor of e). The estimated atmospheric lifetime of 137Cs can also be used as an estimate of the lifetime of aerosols in the atmosphere. This is based on the fact that 137Cs attaches to the ambient accumulation-mode (AM) aerosols and trace their fate in the atmosphere. The 137Cs "tags" the AM aerosols and both the 137Cs and AM aerosols are removed simultaneously from the atmosphere by scavenging within clouds, precipitation and dry deposition. The 137Cs emitted from Fukushima attached mainly to sulphate aerosols in the size range 0.1-2 ?m diameter. Measured 137Cs activity concentrations from several stations spread mostly over the Northern Hemisphere were evaluated, and the decrease in activity concentrations over time (after correction for radioactive decay) reflects the removal of aerosols by wet and dry deposition. Corrections for air mass transport were made using measurements of the noble gas xenon-133 (133Xe) which was also released during the accident. This noble gas does not attach to the aerosols and was thus used as a passive tracer of air mass transport. The atmospheric lifetime of 137Cs was estimated to 10.0-13.9 days during April and May 2011. This represents the atmospheric lifetime of a "background" AM aerosol well mixed in the extratropical northern hemisphere troposphere. It is expected that the lifetime of this vertically mixed background aerosol is longer than the lifetime of fresh AM aerosols directly emitted from surface sources. Possible caveats like late emissions and resuspension were found not to significantly affect the results. The estimated lifetimes from this study are within the much larger and uncertain range of previously observation-based studies of aerosol lifetimes (less than 4 days to more than a month). However, modelled aerosol lifetimes from air quality and climate models typically range 3-7 days which is substantially lower than the mean AM lifetimes obtained from this study. The difference points towards a too quick removal of AM aerosol in the models and further research on the cause of this discrepancy is warranted. Too short modelled AM aerosol lifetimes would have serious implications for air quality and climate model predictions. By running several major climate and air quality models for the Fukushima case, an evaluation of the models performance compared to the measurements can be directly obtained.

Iren Kristiansen, Nina; Stohl, Andreas; Wotawa, Gerhard

2013-04-01

296

NEW APPROACHES: Measurement of the mean lifetime of cosmic ray muons in the A-level laboratory  

NASA Astrophysics Data System (ADS)

The Turning Points in Physics module from the NEAB A-level Modular Physics syllabus requires students to have an understanding of relativistic time dilation and offers the measurement of the mean lifetime of cosmic ray muons as an example of supporting experimental evidence. This article describes a direct measurement of muon lifetime carried out in the A-level laboratory.

Dunne, Peter; Costich, David; O'Sullivan, Sean

1998-09-01

297

Measurement of the {lambda}{sub b}{sup 0} Lifetime Using Semileptonic Decays  

SciTech Connect

We report a measurement of the {lambda}{sub b}{sup 0} lifetime using a sample corresponding to 1.3 fb{sup -1} of data collected by the D0 experiment in 2002-2006 during run II of the Fermilab Tevatron collider. The {lambda}{sub b}{sup 0} baryon is reconstructed via the decay {lambda}{sub b}{sup 0}{yields}{mu}{nu}{lambda}{sub c}{sup +}X. Using 4437{+-}329 signal candidates, we measure the {lambda}{sub b}{sup 0} lifetime to be {tau}({lambda}{sub b}{sup 0})=1.290{sub -0.110}{sup +0.119}(stat){sub -0.091}{sup +0.08} = 7(syst) ps, which is among the most precise measurements in semileptonic {lambda}{sub b}{sup 0} decays. This result is in good agreement with the world average value.

Abazov, V. M.; Alexeev, G. D.; Kalinin, A. M.; Kharzheev, Y. M.; Malyshev, V. L.; Tokmenin, V. V.; Vertogradov, L. S.; Yatsunenko, Y. A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Abbott, B.; Gutierrez, P.; Hall, I.; Hossain, S.; Jain, S.; Kopal, M.; Pompos, A.; Severini, H.; Skubic, P.; Strauss, M. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Abolins, M.; Benitez, J. A. [Michigan State University, East Lansing, Michigan 48824 (United States)] (and others)

2007-11-02

298

A lifetime correction method of gamma-ray yield measurement for (n,x{gamma}) experiments  

SciTech Connect

A lifetime correction method of gamma-ray yield measurement for (n,x{gamma}) experiment is proposed. This method makes it possible to determine simultaneously prompt and non-prompt gamma-ray data in an experiment. It can separate non-prompt component from a mixed gamma-ray peak exactly, so we can obtain completely pure prompt gamma-ray data. It provides an in-beam measurement method of neutron activation cross section, especially, it has obvious advantages for yield measurement of decay gamma-ray with lifetime ranged from 1 ns to several hours. As examples, some results of F, Al and Si samples under 14.9 MeV neutron bombardment were given.

Zhou Hongyu; Huang Guangshun; Fan Guoying [Beijing Normal Univ. (China)

1994-12-31

299

Prospects for a new cold neutron beam measurement of the neutron lifetime  

SciTech Connect

In the most accurate cold neutron beam determination of the neutron lifetime based on the absolute counting of decay protons, the largest uncertainty was attributed to the absolute determination of the capture flux of the cold neutron beam. Currently an experimental effort is underway at the National Institute of Standards and Technology (NIST) that will significantly reduce this contribution to the uncertainty in the lifetime determination. The next largest source of uncertainty is the determination of the absolute count rate of decay protons, which contributes to the experimental uncertainty approximately at the 1 s level. Experience with the recent neutron radiative decay experiment, which used the neutron lifetime apparatus, has provided valuable insights into ways to reduce other uncertainties. In addition, the cold neutron fluence rate at NIST is presently 1.5 times greater than in the 2003 measurement, and there is the prospect for a significantly higher rate with the new guide hall expansion. This paper discusses an approach for achieving a determination of the neutron lifetime with an accuracy of approximately 1 s.

Greene, Geoffrey L [ORNL; Snow, William M [ORNL; Dewey, M. [National Institute of Standards and Technology (NIST), Gaithersburg, MD; Gilliam, D [National Institute of Standards and Technology (NIST), Gaithersburg, MD; Nico, Jeffrey S [ORNL; Coakley, K [National Institute of Standards and Technology (NIST), Boulder; Yue, A [University of Tennessee, Knoxville (UTK); Laptev, A [Los Alamos National Laboratory (LANL); Wietfeldt, F [Tulane University

2009-01-01

300

Prospects for a new cold neutron beam measurement of theneutron lifetime  

SciTech Connect

In the most accurate cold neutron beam determination of the neutron lifetime based on the absolute counting of decay protons, the largest uncertainty was attributed to the absolute determination of the capture flux of the cold neutron beam. Currently an experimental effort is underway at the National Institute of Standards and Technology (NIST) that will significantly reduce this contribution to the uncertainty in the lifetime determination. The next largest source of uncertainty is the determination of the absolute count rate of decay protons, which contributes to the experimental uncertainty approximately at the 1 s level. Experience with the recent neutron radiative decay experiment, which used the neutron lifetime apparatus, has provided valuable insights into ways to reduce other uncertainties. In addition, the cold neutron fluence rate at NIST is presently 1.5 times greater than in the 2003 measurement, and there is the prospect for a significantly higher rate with the new guide hall expansion. This paper discusses an approach for achieving a determination of the neutron lifetime with an accuracy of approximately 1 s.

Dewey, M. [National Institute of Standards and Technology (NIST), Gaithersburg, MD; Gilliam, D [National Institute of Standards and Technology (NIST), Gaithersburg, MD; Coakley, K [National Institute of Standards and Technology (NIST), Boulder; Greene, G [University of Tennessee, Knoxville (UTK); Yue, A [University of Tennessee, Knoxville (UTK); Greene, G [Oak Ridge National Laboratory (ORNL); Laptev, A [Los Alamos National Laboratory (LANL); Snow, W [Indiana University Cyclotron Facility, Bloomington, IN; Wietfeldt, F [Tulane University

2009-01-01

301

Lifetime measurements of first excited states in {sup 16,18}C  

SciTech Connect

The electric quadrupole transition from the first 2{sup +} state to the ground 0{sup +} state in {sup 18}C was studied through a lifetime measurement by an upgraded recoil shadow method applied to inelastically scattered radioactive {sup 18}C nuclei. The measured mean lifetime is 18.9{+-}0.9(stat){+-}4.4(syst) ps, corresponding to a B(E2;2{sub 1}{sup +}{yields}0{sub g.s.}{sup +}) value of 4.3{+-}0.2{+-}1.0 e{sup 2} fm{sup 4}, or about 1.5 Weisskopf units. The mean lifetime of the first 2{sup +} state in {sup 16}C was remeasured to be 18.3{+-}1.4{+-}4.8 ps, about four times shorter than the value reported previously. The discrepancy between the two results was explained by incorporating the {gamma}-ray angular distribution measured in this work into the previous measurement. These transition strengths are hindered compared to the empirical transition strengths, indicating that the anomalous hindrance observed in {sup 16}C persists in {sup 18}C.

Ong, H. J. [Department of Physics, University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-0033 (Japan); RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Imai, N.; Takeuchi, S.; Aoi, N.; Baba, H.; Bishop, S.; Ishihara, M.; Kubo, T.; Motobayashi, T.; Yanagisawa, Y. [RIKEN Nishina Center, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Suzuki, D.; Iwasaki, H.; Sakurai, H.; Onishi, T. K.; Suzuki, M. K.; Nakao, T.; Ichikawa, Y. [Department of Physics, University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-0033 (Japan); Ota, S. [Center for Nuclear Study, University of Tokyo, RIKEN campus, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Togano, Y.; Kurita, K. [Department of Physics, Rikkyo University, Nishi-Ikebukuro 3-34-1, Toshima, Tokyo 171-8501 (Japan)] (and others)

2008-07-15

302

a Measurement of the Average Lifetime of Hadrons Containing Bottom Quarks.  

NASA Astrophysics Data System (ADS)

This thesis reports a measurement of the average lifetime of hadrons containing bottom quarks. It is based on data taken with the DELCO detector at the PEP e('+)e(' -) storage ring at a center of mass energy of 29 GeV. The decays of hadrons containing bottom quarks are tagged in hadronic events by the presence of electrons with a large component of momentum transverse to the event axis. Such electrons are identified in the DELCO detector by an atmospheric. pressure Cerenkov counter assisted by a lead/scintillator electro- magnetic shower counter. The lifetime measured is. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). consistent with previous measurements. This measurement, in conjunction with a limit on the non-charm branching ratio in b-decay obtained by other experiments, can be used to constrain. the magnitude of the Vcb element of the Kobayashi -Maskawa matrix to the range. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). where the errors reflect the uncertainty on (tau)(,b) only and not the uncertainties in the calculations which relate the b-lifetime and the element of the Kobayashi -Maskawa matrix.

Klem, Daniel Edward

303

Application of the Time of Flight Technique for Lifetime Measurements with Relativistic Beams of Heavy Nuclei  

E-print Network

A novel method for picosecond lifetime measurements of excited gamma-ray emitting nuclear states has been developed for fast beams from fragmentation reactions. A test measurement was carried out with a beam of 124Xe at an energy of ~55 MeV/u. The beam ions were Coulomb excited to the first 2+ state on a movable target. Excited nuclei emerged from the target and decayed in flight after a distance related to the lifetime. A stationary degrader positioned downstream with respect to the target was used to further reduce the velocity of the excited nuclei. As a consequence, the gamma-ray decays from the 2+ excited state that occurred before or after traversing the degrader were measured at a different Doppler shift. The gamma-ray spectra were analyzed from the forward ring of the Segmented Germanium Array; this ring positioned at 37 deg. simultaneously provides the largest sensitivity to changes in velocity and the best energy resolution. The ratio of intensities in the peaks at different Doppler shifts gives information about the lifetime if the velocity is measured. The results and range of the application of the method are discussed.

A. Chester; P. Adrich; A. Becerril; D. Bazin; C. M. Campbell; J. M. Cook; D. -C. Dinca; W. F. Mueller; D. Miller; V. Moeller; R. P. Norris; M. Portillo; K. Starosta; A. Stolz; J. R. Terry; H. Zwahlen; C. Vaman; A. Dewald

2005-12-31

304

Silicon Surface and Heterojunction Interface Passivation Studies by Lifetime Measurements: Preprint  

SciTech Connect

We report two investigations conducted by using photoconductivity decay lifetime measurement. The first is crystalline silicon (c-Si) surface passivation using quinhydrone/methanol (QM) for bulk minority-carrier lifetime measurement. QM shows great promise as a substitute for iodine-based solutions because of its superior stability and minimized surface-recombination velocity in silicon. The second is interface passivation in an amorphous silicon (a-Si)/c-Si heterojunction structure as a parallel effort to develop and optimize heterojunction c-Si solar cells by hot-wire chemical vapor deposition (HWCVD). A thin buffer layer inserted between the a-Si and the c-Si substrate has been found to be much more effective than a directly deposited a-Si/c-Si interface in reducing the interface recombination velocity.

Page, M. R.; Wang, Q.; Wang, T. H.; Johnston, S. W.; Ciszek, T. F.

2003-08-01

305

Measurement of the Lifetime of the B(±)(c) Meson in the Semileptonic Decay Channel  

E-print Network

; published 2 March 2009) Using approximately 1:3 fb#2;1 of data collected by the D0 detector between 2002 and 2006, we measure the lifetime of the B#1;c meson in the B#1;c ! J=c#1;#1; þ X final state. A simultaneous unbinned likelihood fit to the J=c þ#1... weakly-decaying b hadrons. Examples of final states where the c quark acts as a spectator while the b quark decays weakly are B#1;c ! J=c#3;#1;, B#1;c ! J=cD#1;s , and B#1;c ! J=c ‘#1;#4;. In this Letter we present a measurement of the lifetime of the B#1...

Baringer, Philip S.; Bean, Alice; Clutter, Justace Randall; Moulik, Tania; Wilson, Graham Wallace

2009-03-02

306

Measurement of the Beta-Decay Lifetime of Magnetically Trapped Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

In this dissertation, the progress towards the measurement of the lifetime of magnetically trapped ultracold neutrons is discussed. Neutrons are trapped in a conservative potential using a series of superconducting magnets arranged in an Ioffe-type field geometry. Neutron energy is dissipated inside the trapping region by undergoing superthermal inelastic downscattering in isotopically purified superfluid 4He that also acts as a scintillator for decay events. Light from the decays are detected using a pair of photomultiplier tubes (PMTs) and decay events are logged using high-speed digitizers. To remove the large amounts of background events present in the data set, a set of software cuts was developed that greatly reduces the background observed for a typical data series. In addition, background measurement runs are subtracted from the trapping data to further reduce background events that are common to both configurations. Preliminary results of the trap lifetime are reported, and the systematic uncertainty is estimated.

Schelhammer, Karl William

307

A Direct Measurement of Lifetimes and Stellar Luminosities on the AGB  

NASA Astrophysics Data System (ADS)

The asymptotic giant branch (AGB) represents the phase of stellar evolution where stars become their brightest and reddest. As such, understanding stellar lifetimes and luminosities during this evolutionary phase is crucial to accurately interpret red and infrared light from galaxies using population synthesis models. Recently, there has been much controversy over the inferred ages and masses of infrared galaxies due to our lack of understanding of this phase. In this presentation, I'll present a direct measurement of the stellar core mass growth on the AGB by comparing the initial core masses to the post AGB core masses measured from spectroscopy of white dwarfs. The resulting data allows us to calculate the stellar lifetime and luminosity on the AGB, and to compare to popular models that are used to interpret light from distant galaxies.

Kalirai, Jason S.; Marigo, Paola; Tremblay, Pier-Emmanuel

2015-01-01

308

Spectroscopy in the Z=49 108,110In isotopes: Lifetime measurements in shears bands  

Microsoft Academic Search

Excited states have been populated in 108In and 110In in complementary backed- and thin-target experiments using the Stony Brook and the 8pi Ge-detector arrays. The level schemes for both isotopes have been extended and modified, including the first observation of DeltaI=2 bands in 110In. Lifetimes of states in four DeltaI=1 bands and one DeltaI=2 band have been measured using the

C. J. Chiara; D. B. Fossan; V. P. Janzen; T. Koike; D. R. Lafosse; S. M. Mullins; E. S. Paul; D. C. Radford; H. Schnare; J. M. Sears; J. F. Smith; K. Starosta; P. Vaska; R. Wadsworth; D. Ward; S. Frauendorf

2001-01-01

309

Measurement of the effective $B_s\\\\rightarrow K^+K^-$ lifetime  

Microsoft Academic Search

A measurement of the effective $B_s\\\\rightarrow K^+K^-$ lifetime is presented using approximately $37 pb^{-1}$ of data collected by LHCb during 2010. This quantity can be used to put constraints on contributions from processes beyond the Standard Model in the $B_s$ meson system and is determined by two complementary approaches as $\\\\tau_{B_s\\\\to K^+K^-} = 1.440 \\\\pm 0.096 (stat) \\\\pm 0.008 (syst)

R. Aaij; C. Abellan Beteta; B. Adeva; M. Adinolfi; C. Adrover; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; Y. Amhis; J. Anderson; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; L. Arrabito; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; S. Bachmann; J. J. Back; D. S. Bailey; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; A. Bates; C. Bauer; Th. Bauer; A. Bay; I. Bediaga; S. Belogurov; K. Belous; I. Belyaev; E. Ben-Haim; M. Benayoun; G. Bencivenni; S. Benson; J. Benton; R. Bernet; M.-O. Bettler; M. van Beuzekom; A. Bien; S. Bifani; A. Bizzeti; P. M. Bjørnstad; T. Blake; F. Blanc; C. Blanks; J. Blouw; S. Blusk; A. Bobrov; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; T. J. V. Bowcock; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; D. Brett; S. Brisbane; M. Britsch; T. Britton; N. H. Brook; H. Brown; A. Büchler-Germann; I. Burducea; A. Bursche; J. Buytaert; S. Cadeddu; J. M. Caicedo Carvajal; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; L. Carson; K. Carvalho Akiba; G. Casse; M. Cattaneo; M. Charles; Ph. Charpentier; N. Chiapolini; K. Ciba; X. Cid Vidal; G. Ciezarek; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; P. Collins; A. Comerma-Montells; F. Constantin; G. Conti; A. Contu; A. Cook; M. Coombes; G. Corti; G. A. Cowan; R. Currie; B. D'Almagne; C. D'Ambrosio; P. David; I. De Bonis; S. De Capua; M. De Cian; F. De Lorenzi; J. M. De Miranda; L. De Paula; P. De Simone; D. Decamp; M. Deckenhoff; H. Degaudenzi; M. Deissenroth; L. Del Buono; C. Deplano; D. Derkach; O. Deschamps; F. Dettori; J. Dickens; H. Dijkstra; P. Diniz Batista; F. Domingo Bonal; S. Donleavy; F. Dordei; A. Dosil Suárez; D. Dossett; A. Dovbnya; F. Dupertuis; R. Dzhelyadin; A. Dziurda; S. Easo; U. Egede; V. Egorychev; S. Eidelman; D. van Eijk; F. Eisele; S. Eisenhardt; R. Ekelhof; L. Eklund; Ch. Elsasser; D. G. d'Enterria; D. Esperante Pereira; L. Estève; A. Falabella; E. Fanchini; C. Färber; G. Fardell; C. Farinelli; S. Farry; V. Fave; V. Fernandez Albor; M. Ferro-Luzzi; S. Filippov; C. Fitzpatrick; M. Fontana; F. Fontanelli; R. Forty; M. Frank; C. Frei; M. Frosini; S. Furcas; A. Gallas Torreira; D. Galli; M. Gandelman; P. Gandini; Y. Gao; J. C. Garnier; J. Garofoli; J. Garra Tico; L. Garrido; D. Gascon; C. Gaspar; N. Gauvin; M. Gersabeck; T. Gershon; Ph. Ghez; V. Gibson; V. V. Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; H. Gordon; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; E. Greening; S. Gregson; B. Gui; E. Gushchin; Yu. Guz; T. Gys; G. Haefeli; C. Haen; S. C. Haines; T. Hampson; S. Hansmann-Menzemer; R. Harji; N. Harnew; J. Harrison; P. F. Harrison; J. He; V. Heijne; K. Hennessy; P. Henrard; J. A. Hernando Morata; E. van Herwijnen; E. Hicks; K. Holubyev; P. Hopchev; W. Hulsbergen; P. Hunt; T. Huse; R. S. Huston; D. Hutchcroft; D. Hynds; V. Iakovenko; P. Ilten; J. Imong; R. Jacobsson; A. Jaeger; M. Jahjah Hussein; E. Jans; F. Jansen; P. Jaton; B. Jean-Marie; F. Jing; M. John; D. Johnson; C. R. Jones; B. Jost; M. Kaballo; S. Kandybei; M. Karacson; T. M. Karbach; J. Keaveney; U. Kerzel; T. Ketel; A. Keune; B. Khanji; Y. M. Kim; M. Knecht; S. Koblitz; P. Koppenburg; A. Kozlinskiy; L. Kravchuk; K. Kreplin; M. Kreps; G. Krocker; P. Krokovny; F. Kruse; K. Kruzelecki; M. Kucharczyk; R. Kumar; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; D. Lambert; R. W. Lambert; E. Lanciotti; G. Lanfranchi; C. Langenbruch; T. Latham; R. Le Gac; J. van Leerdam; J.-P. Lees; R. Lefévre; A. Leflat; J. Lefrançois; O. Leroy; T. Lesiak; L. Li; L. Li Gioi; M. Lieng; M. Liles; R. Lindner; C. Linn; B. Liu; G. Liu; J. H. Lopes; E. Lopez Asamar; N. Lopez-March; J. Luisier; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; J. Magnin; S. Malde; R. M. D. Mamunur; G. Manca; G. Mancinelli; N. Mangiafave; U. Marconi; R. Märki; J. Marks; G. Martellotti; A. Martens; L. Martin; A. Martín Sánchez; D. Martinez Santos; A. Massafferri; Z. Mathe; C. Matteuzzi; M. Matveev; E. Maurice; B. Maynard; A. Mazurov; G. McGregor; R. McNulty; C. Mclean; M. Meissner; M. Merk; J. Merkel; R. Messi; S. Miglioranzi; D. A. Milanes; M.-N. Minard; S. Monteil; D. Moran; P. Morawski; I. Mous; F. Muheim; K. Müller; R. Muresan; B. Muryn; M. Musy; J. Mylroie-Smith; P. Naik; T. Nakada; R. Nandakumar; J. Nardulli; I. Nasteva; M. Nedos; M. Needham; N. Neufeld; C. Nguyen-Mau; M. Nicol; S. Nies; V. Niess; N. Nikitin; A. Nomerotski; A. Novoselov; A. Oblakowska-Mucha; V. Obraztsov; S. Oggero; S. Ogilvy; O. Okhrimenko; R. Oldeman; M. Orlandea; J. M. Otalora Goicochea; P. Owen; K. Pal; J. Palacios; A. Palano; M. Palutan

2011-01-01

310

Line identification and lifetime measurements in the XUV and soft X-ray regions  

NASA Technical Reports Server (NTRS)

A summary of the data acquired concerning line identification and lifetime measurements in the xuv and soft X-ray regions for a variety of both resonance transitions and forbidden transitions in ions of astrophysical interest is provided. Particular attention is called to a few papers which appeared in the Astrophysical Journal. These are of special relevance to specific astrophysical data needs. The many experiments completed in areas related to but somewhat outside the confines of the project title are mentioned.

Sellin, I. A.

1979-01-01

311

UCN?: Study of Lifetime Measurement in a Magneto-Gravitational Trap  

NASA Astrophysics Data System (ADS)

The UCN? project is intended to develop a new measurement of the neutron lifetime using ultra-cold neutrons (UCNs) stored in a magneto-gravitational trap. In this article, we will describe the development of the experiment so far, including the trap itself, the UCN transport and monitoring system, the neutron detection methods, and the Monte Carlo simulations that have been used to model these elements. Finally, we will describe the first systematic effects that we plan to study using this apparatus.

Saunders, Alexander; Salvat, D.; Adamek, E.; Bowman, D.; Clayton, S.; Cude, C.; Fox, W.; Hogan, G.; Hickerson, K.; Holley, A. T.; Liu, C.-Y.; Makela, M.; Manus, G.; Morris, C.; Penttila, S.; Ramsey, J.; Sawtelle, S.; Solberg, K.; Vanderwerp, J.; Vorndick, B.; Walstrom, P.; Wang, Z.; Young, A. R.

2014-03-01

312

Positron Reaction Microscope  

NASA Astrophysics Data System (ADS)

We are developing a positron reaction microscope to measure kinematically complete ionization reactions of atoms and dissociative ionization of simple molecules by positron impact. The experiment is designed to use the slow positron beamline at the ARC Centre for Antimatter Matter Studies (CAMS) node at the Australian National University (ANU). This project is a collaboration among the University of North Texas, CAMS, and the Max Planck Insitute for Kern Phyzik in Heidelberg. Initial measurements and apparatus calibration will be performed using electrons. For positron measurements, the apparatus will be rolled into position on the slow positron beamline at the CAMS site at ANU.

Mueller, D. W.; Lee, C.; Vermet, C.; Armitage, S.; Slaughter, D.; Hargrave, L.; Dorn, A.; Brunton, J.; Buckman, S. J.; Sullivan, J. P.

2012-06-01

313

Measurement of the B- lifetime using a simulation free approach for trigger bias correction  

NASA Astrophysics Data System (ADS)

The collection of a large number of B-hadron decays to hadronic final states at the CDF II Detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper-decay-time distribution. A lifetime measurement must correct for this bias, and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper, we present an analytic method for bias correction without using simulation, thereby removing any uncertainty due to the differences between data and simulation. This method is presented in the form of a measurement of the lifetime of the B- using the mode B-?D0?-. The B- lifetime is measured as ?B-=1.663±0.023±0.015ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.

Aaltonen, T.; Adelman, J.; Álvarez González, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.; Apresyan, A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Attal, A.; Aurisano, A.; Azfar, F.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauer, G.; Beauchemin, P.-H.; Bedeschi, F.; Beecher, D.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Binkley, M.; Bisello, D.; Bizjak, I.; Blair, R. E.; Blocker, C.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boisvert, V.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brau, B.; Bridgeman, A.; Brigliadori, L.; Bromberg, C.; Brubaker, E.; Budagov, J.; Budd, H. S.; Budd, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buzatu, A.; Byrum, K. L.; Cabrera, S.; Calancha, C.; Camarda, S.; Campanelli, M.; Campbell, M.; Canelli, F.; Canepa, A.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Carron, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chang, S. H.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Chlebana, F.; Cho, K.; Chokheli, D.; Chou, J. P.; Chung, K.; Chung, W. H.; Chung, Y. S.; Chwalek, T.; Ciobanu, C. I.; Ciocci, M. A.; Clark, A.; Clark, D.; Compostella, G.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Crescioli, F.; Cuenca Almenar, C.; Cuevas, J.; Culbertson, R.; Cully, J. C.; Dagenhart, D.; D'Ascenzo, N.; Datta, M.; Davies, T.; de Barbaro, P.; de Cecco, S.; Deisher, A.; de Lorenzo, G.; Dell'Orso, M.; Deluca, C.; Demortier, L.; Deng, J.; Deninno, M.; D'Errico, M.; di Canto, A.; di Ruzza, B.; Dittmann, J. R.; D'Onofrio, M.; Donati, S.; Dong, P.; Dorigo, T.; Dube, S.; Ebina, K.; Elagin, A.; Erbacher, R.; Errede, D.; Errede, S.; Ershaidat, N.; Eusebi, R.; Fang, H. C.; Farrington, S.; Fedorko, W. T.; Feild, R. G.; Feindt, M.; Fernandez, J. P.; Ferrazza, C.; Field, R.; Flanagan, G.; Forrest, R.; Frank, M. J.; Franklin, M.; Freeman, J. C.; Furic, I.; Gallinaro, M.; Galyardt, J.; Garberson, F.; Garcia, J. E.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerdes, D.; Gessler, A.; Giagu, S.; Giakoumopoulou, V.; Giannetti, P.; Gibson, K.; Gimmell, J. L.; Ginsburg, C. M.; Giokaris, N.; Giordani, M.; Giromini, P.; Giunta, M.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldschmidt, N.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gresele, A.; Grinstein, S.; Grosso-Pilcher, C.; Group, R. C.; Grundler, U.; Guimaraes da Costa, J.; Gunay-Unalan, Z.; Haber, C.; Hahn, S. R.; Halkiadakis, E.; Han, B.-Y.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, D.; Hare, M.; Harr, R. F.; Hartz, M.; Hatakeyama, K.; Hays, C.; Heck, M.; Heinrich, J.; Herndon, M.; Heuser, J.; Hewamanage, S.; Hidas, D.; Hill, C. S.; Hirschbuehl, D.; Hocker, A.; Hou, S.; Houlden, M.; Hsu, S.-C.; Hughes, R. E.; Huffman, B. T.; Hurwitz, M.; Husemann, U.; Hussein, M.; Huston, J.; Incandela, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jha, M. K.; Jindariani, S.; Johnson, W.; Jones, M.; Joo, K. K.; Jun, S. Y.; Jung, J. E.; Junk, T. R.; Kamon, T.; Kar, D.; Karchin, P. E.; Kato, Y.; Kephart, R.; Ketchum, W.; Keung, J.; Khotilovich, V.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, H. W.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kimura, N.; Kirsch, L.; Klimenko, S.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Korytov, A.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Krop, D.; Krumnack, N.; Kruse, M.; Krutelyov, V.; Kuhr, T.; Kulkarni, N. P.; Kurata, M.; Kwang, S.; Laasanen, A. T.; Lami, S.; Lammel, S.; Lancaster, M.; Lander, R. L.; Lannon, K.; Lath, A.; Latino, G.; Lazzizzera, I.; Lecompte, T.; Lee, E.; Lee, H. S.; Lee, J. S.; Lee, S. W.; Leone, S.; Lewis, J. D.; Lin, C.-J.; Linacre, J.; Lindgren, M.; Lipeles, E.; Lister, A.; Litvintsev, D. O.; Liu, C.; Liu, T.; Lockyer, N. S.; Loginov, A.; Lovas, L.; Lucchesi, D.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lyons, L.; Lys, J.; Lysak, R.; MacQueen, D.; Madrak, R.; Maeshima, K.; Makhoul, K.; Maksimovic, P.; Malde, S.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Margaroli, F.; Marino, C.; Marino, C. P.; Martin, A.; Martin, V.; Martínez, M.; Martínez-Ballarín, R.; Mastrandrea, P.; Mathis, M.; Mattson, M. E.; Mazzanti, P.; McFarland, K. S.; McIntyre, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Menzione, A.; Mesropian, C.; Miao, T.; Mietlicki, D.; Miladinovic, N.; Miller, R.; Mills, C.; Milnik, M.; Mitra, A.; Mitselmakher, G.; Miyake, H.; Moed, S.; Moggi, N.; Mondragon, M. N.; Moon, C. S.; Moore, R.; Morello, M. J.; Morlock, J.; Movilla Fernandez, P.; Mülmenstädt, J.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.

2011-02-01

314

Subcellular localization-dependent changes in EGFP fluorescence lifetime measured by time-resolved flow cytometry  

PubMed Central

Intracellular protein transport and localization to subcellular regions are processes necessary for normal protein function. Fluorescent proteins can be fused to proteins of interest to track movement and determine localization within a cell. Currently, fluorescence microscopy combined with image processing is most often used to study protein movement and subcellular localization. In this contribution we evaluate a high-throughput time-resolved flow cytometry approach to correlate intracellular localization of human LC3 protein with the fluorescence lifetime of enhanced green fluorescent protein (EGFP). Subcellular LC3 localization to autophagosomes is a marker of the cellular process called autophagy. In breast cancer cells expressing native EGFP and EGFP-LC3 fusion proteins, we measured the fluorescence intensity and lifetime of (i) diffuse EGFP (ii) punctate EGFP-LC3 and (iii) diffuse EGFP-?LC3 after amino acid starvation to induce autophagy-dependent LC3 localization. We verify EGFP-LC3 localization with low-throughput confocal microscopy and compare to fluorescence intensity measured by standard flow cytometry. Our results demonstrate that time-resolved flow cytometry can be correlated to subcellular localization of EGFP fusion proteins by measuring changes in fluorescence lifetime. PMID:24010001

Gohar, Ali Vaziri; Cao, Ruofan; Jenkins, Patrick; Li, Wenyan; Houston, Jessica P.; Houston, Kevin D.

2013-01-01

315

Measurement of the $B^-$ lifetime using a simulation free approach for trigger bias correction  

E-print Network

The collection of a large number of $B$ hadron decays to hadronic final states at the CDF II detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper decay time distribution. A lifetime measurement must correct for this bias and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper we present an analytic method for bias correction without using simulation, thereby removing any uncertainty between data and simulation. This method is presented in the form of a measurement of the lifetime of the $B^{-}$ using the mode B -> D0 pi. The $B^-$ lifetime is measured as $\\tau_{B^-}$ = 1.663 $\\pm$ 0.023 $\\pm$ 0.015 ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.

The CDF Collaboration; T. Aaltonen

2011-02-25

316

Radiative-lifetime measurements and calculations of odd-parity highly excited levels in Ba i  

NASA Astrophysics Data System (ADS)

Natural radiative lifetime measurements have been performed for 70 odd-parity highly excited levels of neutral barium in the energy range from 308 15.512 to 417 59.93 cm-1 by a time-resolved laser-induced fluorescence technique in a laser-produced plasma. The lifetime values measured in this paper are in the range from 11.3 to 901 ns. They are compared with the published lifetimes of four levels. Two of them are in good agreement, whereas for the other two our measurements are slightly longer than the published data. The reasons for the discrepancies are discussed. Comparisons with theoretical results of the Hartree-Fock method with relativistic corrections illustrate the difficulties associated with the use of Cowan’s codes for obtaining accurate branching fractions for transitions depopulating highly excited levels along the Rydberg series of heavy neutral elements. This work will be useful to extend the set of oscillator strengths available in Ba i.

Zhang, Wei; Palmeri, Patrick; Quinet, Pascal; Biémont, Émile; Du, Shan; Dai, Zhenwen

2010-10-01

317

Measurement of the $B^-$ lifetime using a simulation free approach for trigger bias correction  

SciTech Connect

The collection of a large number of B hadron decays to hadronic final states at the CDF II detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper decay time distribution. A lifetime measurement must correct for this bias and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper they present an analytic method for bias correction without using simulation, thereby removing any uncertainty between data and simulation. This method is presented in the form of a measurement of the lifetime of the B{sup -} using the mode B{sup -} {yields} D{sup 0}{pi}{sup -}. The B{sup -} lifetime is measured as {tau}{sub B{sup -}} = 1.663 {+-} 0.023 {+-} 0.015 ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.

Aaltonen, T.; /Helsinki Inst. of Phys.; Adelman, J.; /Chicago U., EFI; Alvarez Gonzalez, B.; /Cantabria Inst. of Phys.; Amerio, S.; /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, A.; /Frascati; Antos, J.; /Comenius U.; Apollinari, G.; /Fermilab; Appel, J.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U.

2010-04-01

318

Application of Positron Doppler Broadening Spectroscopy to the Measurement of the Uniformity of Composite Materials  

SciTech Connect

The uniformity of rubber-carbon black composite materials has been investigated with positron Doppler Broadening Spectroscopy (DBS). The number of grams of carbon black (CB) mixed into one hundred grams of rubber, phr, is used to characterize a sample. A typical concentration for rubber in tires is 50 phr. The S parameter measured by DBS has been found to depend on the phr of the sample as well as the type of rubber and carbon black. The variation in carbon black concentration within a surface area of about 5 mm diameter can be measured by moving a standard Na-22 or Ge-68 positron source over an extended sample. The precision of the concentration measurement depends on the dwell time at a point on the sample. The time required to determine uniformity over an extended sample can be reduced by running with much higher counting rate than is typical in DBS and correcting for the systematic variation of S parameter with counting rate. Variation in CB concentration with mixing time at the level of about 0.5% has been observed.

Quarles, C. A.; Sheffield, Thomas; Stacy, Scott; Yang, Chun [Department of Physics and Astronomy, Texas Christian University, Fort Worth TX 76129 (United States)

2009-03-10

319

On the Uncertainty in Single Molecule Fluorescent Lifetime and Energy Emission Measurements  

NASA Technical Reports Server (NTRS)

Time-correlated single photon counting has recently been combined with mode-locked picosecond pulsed excitation to measure the fluorescent lifetimes and energy emissions of single molecules in a flow stream. Maximum likelihood (ML) and least squares methods agree and are optimal when the number of detected photons is large, however, in single molecule fluorescence experiments the number of detected photons can be less than 20, 67 percent of those can be noise, and the detection time is restricted to 10 nanoseconds. Under the assumption that the photon signal and background noise are two independent inhomogeneous Poisson processes, we derive the exact joint arrival time probability density of the photons collected in a single counting experiment performed in the presence of background noise. The model obviates the need to bin experimental data for analysis, and makes it possible to analyze formally the effect of background noise on the photon detection experiment using both ML or Bayesian methods. For both methods we derive the joint and marginal probability densities of the fluorescent lifetime and fluorescent emission. The ML and Bayesian methods are compared in an analysis of simulated single molecule fluorescence experiments of Rhodamine 110 using different combinations of expected background noise and expected fluorescence emission. While both the ML or Bayesian procedures perform well for analyzing fluorescence emissions, the Bayesian methods provide more realistic measures of uncertainty in the fluorescent lifetimes. The Bayesian methods would be especially useful for measuring uncertainty in fluorescent lifetime estimates in current single molecule flow stream experiments where the expected fluorescence emission is low. Both the ML and Bayesian algorithms can be automated for applications in molecular biology.

Brown, Emery N.; Zhang, Zhenhua; McCollom, Alex D.

1996-01-01

320

On the uncertainty in single molecule fluorescent lifetime and energy emission measurements  

NASA Technical Reports Server (NTRS)

Time-correlated single photon counting has recently been combined with mode-locked picosecond pulsed excitation to measure the fluorescent lifetimes and energy emissions of single molecules in a flow stream. Maximum likelihood (ML) and least square methods agree and are optimal when the number of detected photons is large however, in single molecule fluorescence experiments the number of detected photons can be less than 20, 67% of those can be noise and the detection time is restricted to 10 nanoseconds. Under the assumption that the photon signal and background noise are two independent inhomogeneous poisson processes, we derive the exact joint arrival time probably density of the photons collected in a single counting experiment performed in the presence of background noise. The model obviates the need to bin experimental data for analysis, and makes it possible to analyze formally the effect of background noise on the photon detection experiment using both ML or Bayesian methods. For both methods we derive the joint and marginal probability densities of the fluorescent lifetime and fluorescent emission. the ML and Bayesian methods are compared in an analysis of simulated single molecule fluorescence experiments of Rhodamine 110 using different combinations of expected background nose and expected fluorescence emission. While both the ML or Bayesian procedures perform well for analyzing fluorescence emissions, the Bayesian methods provide more realistic measures of uncertainty in the fluorescent lifetimes. The Bayesian methods would be especially useful for measuring uncertainty in fluorescent lifetime estimates in current single molecule flow stream experiments where the expected fluorescence emission is low. Both the ML and Bayesian algorithms can be automated for applications in molecular biology.

Brown, Emery N.; Zhang, Zhenhua; Mccollom, Alex D.

1995-01-01

321

Positron Annihilation Spectroscopy Of High Performance Polymer Films Under CO{sub 2} Pressure  

SciTech Connect

Positron annihilation Lifetime and Doppler broadening measurements are reported for six polymer films as a function of carbon dioxide (CO{sub 2}) absolute pressure ranging from 0 to 45 psi. Since the polymer films were thin and did not absorb all positrons, corrections were made in the lifetime analysis for the absorption of positrons in the positron source and sample holder using the Monte Carlo transport code MCNP. The studied polymers are found to behave differently from each other. Some polymers form positronium and others, such as the polyimide structures, do not. For those polymers that form positronium an interpretation in terms of free volume is possible; for those that don't form positronium, further work is needed to determine how best to describe the behavior in terms of the bulk positron annihilation parameters. A few of the studied polymers exhibit changes in positron lifetime and intensity under CO{sub 2} pressure which may be described by the Henry or Langmuir sorption models, while the positron response of other polymers is rather insensitive to the CO{sub 2} pressure. The results demonstrate the usefulness of positron annihilation spectroscopy in investigating the sorption of CO{sub 2} into various polymers at pressures up to about 3 atm (45psi).

Quarles, C. A. [Texas Christian University, Fort Worth TX 76109 (United States); Klaehn, John R.; Peterson, Eric S. [Idaho National Laboratory, Idaho Falls ID 83415-2208 (United States); Urban-Klaehn, Jagoda M. [Pajarito Scientific Corporation, Idaho Falls ID 83404 (United States)

2011-06-01

322

High resolution positron Q-value measurements and nuclear structure studies far from the stability line. Progress report, July 1, 1979-June 30, 1980. [Dept. of Physics and Astronomy, Univ. of South Carolina, Columbia  

SciTech Connect

This document represents a progress report and renewal proposal for the contract DEAS 09 79 ER10434 between the USDOE and USC. During the time from 1 July 1979 to 1 March 1980, the large 35% intrinsic Ge detector was purchased and tested, and the new hyperpure Ge detector for positron end-point-energy measurements was designed and fabricated by ORTEC. It was delivered just prior to January 1, 1980. Measurements using this special equipment began in January 1980. During this period, a new effort in the measurement of short nuclear lifetimes was completed, and nuclear structure measurements of /sup 206/Rn nd /sup 208/Rn were completed. The results of these efforts are described in the text. A search for the Post Doctoral Research Associate was started last summer and the position will be filled on or about 1 March 1980. The first experiments to measure positron end-point-energies were proposed to the ORIC scheduling committee, and measurements will begin in March 1980. Theoretical efforts describe accurately the interference of annihilation radiation with positron end-point-energy measurements were begun.

Avignone, F.T. III

1980-02-22

323

Fracture aperture evolution during carbonate dissolution measured using positron emission projection imaging.  

NASA Astrophysics Data System (ADS)

Fracture flow (and fracture aperture) is of primary importance in hydrogeological studies and fracture development as a result of dissolution is significant in geological environments such as Karstic aquifers. The development of the fracture aperture is dependent on coupled flow and dissolution/precipitation processes that are difficult to investigate directly. We use Positron Emission Projection Imaging (PEPI) to quantify the evolution of fracture aperture during the dissolution of a carbonate rock under laminar flow conditions. Acidified water is passed through an initially smooth walled fracture between two limestone blocks and the levels of Ca, ppCO_2, pH and temperature are monitored continuously. At regular intervals the fracture aperture is measured using PEPI. Data from the experiment provides input to a numerical model that is used to investigate the relationship between the changing aperture distribution, flow and dissolution rates and the mineralogy of the fracture surface. Positron Emission Projection Imaging (PEPI) has been developed at the University of Birmingham for the study of solute and particle transport in aquifer forming rocks. The technique has been adapted from Positron Emission Tomography (PET) used predominantly for medical investigations. Positrons emitted from a suitable tracer collide with electrons within the sample which results in annihilation of both particles and the emission of two co-linear gamma rays. Detectors enable the distribution of the tracer to be calculated from the observation of many annihilation events. Using PEPI it is possible to observe the transport of tracers within a rock in time and space. In the case of a fracture, the aperture distribution can be measured, as, in the case of a uniformly concentrated solution, the activity is proportional to the aperture. Advantages of PEPI over other non-invasive methods such as nuclear magnetic resonance imaging (NMRI) include a large field of view (30 x 30 cm), greater resolution of aperture and rapid imaging time (as little as 1 minute). This paper presents the initial results from experiments to examine the evolution of aperture within a block of fractured limestone undergoing dissolution.

Ellis, P.; Greswell, R.; Riley, M.; Isakov, E.; Parker, D.

2003-04-01

324

Measurement of the {ital B}{sub {ital s}} meson lifetime  

SciTech Connect

The lifetime of the {ital B}{sub {ital s}} meson is measured using the semileptonic decay {ital B}{sub {ital s}}{r_arrow}{ital D}{sub {ital s}}{sup {minus}}l{sup +}{nu}{ital X}. The data sample consists of 19.3 pb{sup {minus}1} of {ital p{bar p}} collisions at {radical}{ital s}=1.8 TeV collected by the Collider Detector at Fermilab during 1992--1993. There are 76{plus_minus}8 l{sup +}{ital D}{sub {ital s}}{sup {minus}} signal events where the {ital D}{sub {ital s}} is identified via the decay {ital D}{sub {ital s}}{sup {minus}}{r_arrow}{phi}{pi}{sup {minus}}, {phi}{r_arrow}{ital K}{sup +}{ital K}{sup {minus}}. Using these events, the {ital B}{sub {ital s}} meson lifetime is determined to be {tau}{sub {ital s}}=1.42{sub {minus}0.23}{sup +0.27}(stat){plus_minus}0.11(syst) ps. A measurement of the {ital B}{sub {ital s}} lifetime in a low statistics sample of exclusive {ital B}{sub {ital s}}{r_arrow}{ital J}/{psi}{phi} decays is also presented in this paper.

Abe, F.; Albrow, M.G.; Amendolia, S.R.; Amidei, D.; Antos, J.; Anway-Wiese, C.; Apollinari, G.; Areti, H.; Atac, M.; Auchincloss, P.; Azfar, F.; Azzi, P.; Bacchetta, N.; Badgett, W.; Bailey, M.W.; Bao, J.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Bartalini, P.; Bauer, G.; Baumann, T.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Benlloch, J.; Bensinger, J.; Benton, D.; Beretvas, A.; Berge, J.P.; Bertolucci, S.; Bhatti, A.; Biery, K.; Binkley, M.; Bird, F.; Bisello, D.; Blair, R.E.; Blocker, C.; Bodek, A.; Bokhari, W.; Bolognesi, V.; Bortoletto, D.; Boswell, C.; Boulos, T.; Brandenburg, G.; Bromberg, C.; Buckley-Geer, E.; Budd, H.S.; Burkett, K.; Busetto, G.; Byon-Wagner, A.; Byrum, K.L.; Cammerata, J.; Campagnari, C.; Campbell, M.; Caner, A.; Carithers, W.; Carlsmith, D.; Castro, A.; Cen, Y.; Cervelli, F.; Chao, H.Y.; Chapman, J.; Cheng, M.; Chiarelli, G.; Chikamatsu, T.; Chiou, C.N.; Cihangir, S.; Clark, A.G.; Cobal, M.; Contreras, M.; Conway, J.; Cooper, J.; Cordelli, M.; Couyoumtzelis, C.; Crane, D.; Cunningham, J.D.; Daniels, T.; DeJongh, F.; Delchamps, S.; Dell`Agnello, S.; Dell`Orso, M.; Demortier, L.; Denby, B.; Deninno, M.; Derwent, P.F.; Devlin, T.; Dickson, M.; Dittmann, J.R.; Donati, S.; Drucker, R.B.; Dunn, A.; Einsweiler, K.; Elias, J.E.; Ely, R.; Engels, E. Jr.; Eno, S.; Errede, D.; Errede, S.; Fan, Q.; Farhat, B.; Fiori, I.; Flaugher, B.; Foster, G.W.; Franklin, M.; Frautschi, M.; Freeman, J.; Friedman, J.; Fry, A.; Fuess, T.A.; Fukui, Y.; Funaki, S.; Gagliardi, G.; Galeotti, S.; Gallinaro, M.; Garfinkel, A.F.; Geer, S.; Gerdes, D.W.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Glenzinski, D.; Gold, M.; Gonzalez, J.; Gordon, A.; Goshaw, A.T.; Goulianos, K.; Grassmann, H.; Grewal, A.; Grieco, G.; Groer, L.; Grosso-Pilcher, C.; Haber, C.; Hahn, S.R.; Hamilton, R.; Handler, R.; Hans, R.M.; Hara, K.; Harral, B.; Harris, R.M.; Hauger, S.A.; Hauser, J.; Hawk, C.; (CDF Collabo..

1995-06-19

325

New measurement capability measures semiconductor minority-carrier lifetimes in conditions that simulate thin-film  

E-print Network

that simulate thin-film photovoltaic manufacturing environments. National Renewable Energy Laboratory (NREL of conditions in a thin-film photovoltaic (PV) manufacturing line. NREL's work in recent years has demonstrated a clear correlation between minority-carrier lifetime and thin-film PV device performance. Hence, the thin-film

326

Direct Measurement of the Radiative Lifetime of Vibrationally Excited OH Radicals  

SciTech Connect

Neutral molecules, isolated in the gas phase, can be prepared in a long-lived excited state and stored in a trap. The long observation time afforded by the trap can then be exploited to measure the radiative lifetime of this state by monitoring the temporal decay of the population in the trap. This method is demonstrated here and used to benchmark the Einstein A coefficients in the Meinel system of OH. A pulsed beam of vibrationally excited OH radicals is Stark decelerated and loaded into an electrostatic quadrupole trap. The radiative lifetime of the upper {lambda}-doublet component of the X {sup 2}{pi}{sub 3/2}, v=1, J=3/2 level is determined as 59.0{+-}2.0 ms, in good agreement with the calculated value of 58.0{+-}1.0 ms.

Meerakker, Sebastiaan Y.T. van de [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany); FOM-Institute for Plasmaphysics Rijnhuizen, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands); Vanhaecke, Nicolas; Meijer, Gerard [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany); Loo, Mark P.J. van der; Groenenboom, Gerrit C. [Institute of Theoretical Chemistry, University of Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands)

2005-07-01

327

MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant  

E-print Network

We report results from the MuLan measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured surface muon beam and a segmented plastic scintillator array. Two different in-vacuum muon stopping targets were used: a ferromagnetic foil with a large internal magnetic field and a quartz crystal in a moderate external magnetic field. From a total of 1.6 x 10^{12} decays, we obtained the muon lifetime tau_mu = 2196980.3(2.2) ps (1.0 ppm) and Fermi constant G_F = 1.1663787(6) x 10^{-5} GeV^{-2} (0.5 ppm).

Gorringe, T P

2013-01-01

328

MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant  

E-print Network

We report results from the MuLan measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured surface muon beam and a segmented plastic scintillator array. Two different in-vacuum muon stopping targets were used: a ferromagnetic foil with a large internal magnetic field and a quartz crystal in a moderate external magnetic field. From a total of 1.6 x 10^{12} decays, we obtained the muon lifetime tau_mu = 2196980.3(2.2) ps (1.0 ppm) and Fermi constant G_F = 1.1663787(6) x 10^{-5} GeV^{-2} (0.5 ppm).

T. P. Gorringe

2013-01-03

329

MuLan; a precision measurement of the muon lifetime and determination of the Fermi constant  

NASA Astrophysics Data System (ADS)

The Fermi constant GF determines the rates of weak processes that range from nuclear beta-decay to stellar nucleo-synthesis. At Paul Scherrer Institute, the MuLan experiment is seeking to determine the Fermi Constant by measuring the positive muon lifetime to an unprecedented precision of about one part-per-million - a twenty-fold improvement over earlier experimental efforts. The experiment uses an intense, pulsed, muon beam and a finely-segmented, fast-timing, scintillator array to record the decays of more than 10^12 muons. In this talk we report the results for the positive muon lifetime from our 2004 production run, and describe our progress to reaching the final goal of one ppm. The implications - both as a determination of a fundamental constant of the electroweak interaction and for the precision testing of the standard model - are also discussed.

Gorringe, Tim

2007-10-01

330

Studies on the Use of Liquid Surface Passivation for Lifetime Measurements on Good-Quality Silicon Wafers  

SciTech Connect

We evaluated several liquid passivants, viz. solutions of iodine ethanol (IE), quinhydrone methanol (QHM), and potassium cyanide (KCN), for measuring minority-carrier lifetime. Lifetime was measured by the WCT-100 (Sinton Instruments) and WT-2000 (Semilab). Our results show that both IE and QHM passivation are reliable mechanisms. We also find that the KCN solution is moderately passivating on oxidized surfaces, but is only minimally effective on bare Si surfaces. This paper presents details of our studies. In particular, the effect of illumination on IE-passivated surfaces and possible reasons for variations in lifetime measurement are discussed.

Devayajanam, S.; Rupnowski, P.; Shet, S.; Sopori, B. L.; Ravindra, N. M.; Caskey, D.; Chang, J.; Covington, J.

2011-01-01

331

Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams  

E-print Network

A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

Y. Arimoto; N. Higashi; Y. Igarashi; Y. Iwashita; T. Ino; R. Katayama; R. Kitahara; M. Kitaguchi; H. Matsumura; K. Mishima; H. Oide; H. Otono; R. Sakakibara; T. Shima; H. M. Shimizu; T. Sugino; N. Sumi; H. Sumino; K. Taketani; G. Tanaka; M. Tanaka; K. Tauchi; A. Toyoda; T. Yamada; S. Yamashita; H. Yokoyama; T. Yoshioka

2015-03-27

332

Improved Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant  

E-print Network

The mean life of the positive muon has been measured to a precision of 11 ppm using a low-energy, pulsed muon beam stopped in a ferromagnetic target, which was surrounded by a scintillator detector array. The result, tau_mu = 2.197013(24) us, is in excellent agreement with the previous world average. The new world average tau_mu = 2.197019(21) us determines the Fermi constant G_F = 1.166371(6) x 10^-5 GeV^-2 (5 ppm). Additionally, the precision measurement of the positive muon lifetime is needed to determine the nucleon pseudoscalar coupling g_P.

MuLan Collaboration; D. B. Chitwood; T. I. Banks; M. J. Barnes; S. Battu; R. M. Carey; S. Cheekatmalla; S. M. Clayton; J. Crnkovic; K. M. Crowe; P. T. Debevec; S. Dhamija; W. Earle; A. Gafarov; K. Giovanetti; T. P. Gorringe; F. E. Gray; M. Hance; D. W. Hertzog; M. F. Hare; P. Kammel; B. Kiburg; J. Kunkle; B. Lauss; I. Logashenko; K. R. Lynch; R. McNabb; J. P. Miller; F. Mulhauser; C. J. G. Onderwater; C. S. Ozben; Q. Peng; C. C. Polly; S. Rath; B. L. Roberts; V. Tishchenko; G. D. Wait; J. Wasserman; D. M. Webber; P. Winter; P. A. Zolnierczuk

2008-02-08

333

Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams  

E-print Network

A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

Arimoto, Y; Igarashi, Y; Iwashita, Y; Ino, T; Katayama, R; Kitahara, R; Kitaguchi, M; Matsumura, H; Mishima, K; Oide, H; Otono, H; Sakakibara, R; Shima, T; Shimizu, H M; Sugino, T; Sumi, N; Sumino, H; Taketani, K; Tanaka, G; Tanaka, M; Tauchi, K; Toyoda, A; Yamada, T; Yamashita, S; Yokoyama, H; Yoshioka, T

2015-01-01

334

B{sub s}{sup 0} mixing and lifetime difference measurements at CDF  

SciTech Connect

We review latest experimental results on the Bs mixing and lifetime difference measurements at CDF. We report on the latest beta{sub s} and DELTAGAMMA{sub s} results from B{sub s}->J/psiphi. We also discuss flavor specific DELTAGAMMA{sub s} measurements, including information from hadronic channels, B{sub s}->D{sub s}D{sub s} and B{sub s}->KK. We describe the new flavor tagging methodology and its calibration using the B{sub s} oscillations.

Catastini, Pierluigi [Siena University and INFN sez. Pisa (Italy)

2010-02-10

335

[Infrared energy level lifetime measurement system by visible upconversion luminescence detection based on double-pulse injection LD module].  

PubMed

The lifetime of Er3+ and 4I13/2 energy level is of very significance for evaluating the application potential of Er(3+)-doped materials in optical communication. In the present article, based on the Er3+ excited state absorption upconversion (UC) luminescence under 980 nm double-pulse injection LD excitation, the authors detected the red UC luminescence intensity under different time gap between double pulses, then according to the dependence between UC red luminescence intensity and time gap between double pulses, deduced the fitting formula for obtained medial energy level lifetime of Er3+, and actualized the measurement of infrared level lifetime in visible region. So, combining photomultiplier tube (R2658) with double-pulse injection LD module with controllable time gap and synchronous pulse sample, we can obtain all the infrared level lifetime of Er3+, and this is a cost saving lifetime measurement system with micros resolution. PMID:23387159

Fan, Xian-Guang; Li, Ai-Hua; Xu, Ying-Jie; Zuo, Yong

2012-11-01

336

European Photovoltaic Solar Energy Conference, Valencia, Spain, 6-10 September 2010, 2CV.3.84 DYNAMIC LIFETIME IMAGING BASED ON PHOTOLUMINESCENCE MEASUREMENTS  

E-print Network

.84 DYNAMIC LIFETIME IMAGING BASED ON PHOTOLUMINESCENCE MEASUREMENTS Sandra Herlufsen1 , Klaus Ramspeck1, D-63755 Alzenau, Germany ABSTRACT: We report on calibration-free photoluminescence carrier lifetime imaging for the examination of crystalline silicon wafers. The photoluminescence measurements

337

Measurement of high-Q2 deep inelastic scattering cross sections with longitudinally polarised positron beams at HERA  

E-print Network

The first measurements of the cross sections for neutral and charged current deep inelastic scattering in e+p collisions with longitudinally polarised positron beams are presented. The total cross section for e+p charged current deep inelastic scattering is presented at positive and negative values of positron beam longitudinal polarisation for an integrated luminosity of 37.0 pb^-1 H1 data and 30.5 pb^-1 ZEUS data collected in 2003 and 2004 at a centre-of-mass energy of 319 GeV. In addition, the ZEUS collaboration measured the single differential cross sections for charged and neutral current deep inelastic scattering in the kinematic region Q^2>200 GeV^2. The measured cross sections are compared with the predictions of the Standard Model. The H1 collaboration extrapolate the cross section to a fully left handed positron beam and find it to be consistent with the Standard Model expectation.

Julian Rautenberg

2005-06-15

338

Measurement of the Lifetime Difference in the B{sub s}{sup 0} System  

SciTech Connect

We present a study of the decay B{sub s}{sup 0}{yields}J/{psi}{phi}. We obtain the CP-odd fraction in the final state at time zero, R{sub perpendicular}=0.16{+-}0.10(stat){+-}0.02(syst), the average lifetime of the (B{sub s}{sup 0}, B{sub s}{sup 0}) system, {tau}(B{sub s}{sup 0})=1.39{sub -0.16}{sup +0.13}(stat){sub -0.02}{sup +0.01}(syst) ps, and the relative width difference between the heavy and light mass eigenstates, {delta}{gamma}/{gamma}{identical_to}({gamma}{sub L}-{gamma}{sub H})/{gamma}=0.24{sub -0.38}{sup +0.28}(stat){sub -0.04}{sup +0=} .{sup 03}(syst). With the additional constraint from the world average of the B{sub s}{sup 0} lifetime measurements using semileptonic decays, we find {tau}(B{sub s}{sup 0})=1.39{+-}0.06 ps and {delta}{gamma}/{gamma}=0.25{sub -0.15}{sup +0.14}. For the ratio of the B{sub s}{sup 0} and B{sup 0} lifetimes we obtain ({tau}(B{sub s}{sup 0})/{tau}(B{sup 0}))=0.91{+-}0.09(stat){+-}0.003(syst)

Abazov, V.M.; Alexeev, G.D.; Kalinin, A.M.; Kharzheev, Y.M.; Malyshev, V.L.; Vertogradov, L.S.; Yatsunenko, Y.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Abbott, B.; Gutierrez, P.; Hall, I.; Jain, S.; Kopal, M.; Pompos, A.; Severini, H.; Skubic, P.; Strauss, M.; Zhang, X. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Abolins, M.; Brock, R.; Dyer, J. [Michigan State University, East Lansing, Michigan 48824 (United States)] [and others

2005-10-21

339

Measurement of the lifetime difference in the B0(s) system.  

PubMed

We present a study of the decay B0(s) --> J/psiphi. We obtain the CP-odd fraction in the final state at time zero, Rperpendicular = 0.16 +/- 0.10(stat) +/- 0.02 (syst), the average lifetime of the (B0(s), B0(s)) system, tau(B0(s)) = 1.39(+0.13)(-0.16)(stat)(+0.01)(-0.02)(syst) ps, and the relative width difference between the heavy and light mass eigenstates, DeltaGamma/Gamma tripple bond (GammaL - GammaH)/Gamma = 0.24(+0.28)(-0.38)(stat)(+0.03)(-0.04)(syst). With the additional constraint from the world average of the lifetime measurements using semileptonic decays, we find tau(B0(s)) = 1.39 +/- 0.06 ps and DeltaGamma/Gamma = 0.25(+0.14)(-0.15). For the ratio of the B0(s) and B0 lifetimes we obtain tau(B0(s))/tau(B0) = 0.91 +/- 0.09(stat) +/- 0.003(syst). PMID:16383817

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, S; Andrieu, B; Arnoud, Y; Arov, M; Askew, A; Asman, B; Jesus, A C S Assis; Atramentov, O; Autermann, C; Avila, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Balm, P W; Banerjee, P; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beauceron, S; Begalli, M; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Cho, D K; Choi, S; Choudhary, B; Christiansen, T; Christofek, L; Claes, D; Clément, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Cothenet, A; Cousinou, M-C; Cox, B; Crépé-Renaudin, S; Cutts, D; Motta, H da; Das, M; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; Martins, C De Oliveira; Dean, S; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dong, H; Doulas, S; Dudko, L V; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, H; Evdokimov, A; Evdokimov, V N; Fast, J; Fatakia, S N; Feligioni, L; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Golling, T; Gollub, N; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Gris, Ph; Grivaz, J-F; Groer, L; Grünendahl, S; Grünewald, M W; Gurzhiev, S N; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hanagaki, K; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Huang, J; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jenkins, A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Karmanov, D; Kasper, J; Katsanos, I; Kau, D; Kaur, R; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A; Kharzheev, Y M; Kim, H; Kim, T J; Klima, B; Kohli, J M; Konrath, J-P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Kryemadhi, A; Krzywdzinski, S; Kulik, Y; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lager, S; Lahrichi, N; Landsberg, G; Lazoflores, J; Le Bihan, A-C; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Leonidopoulos, C; Leveque, J; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Love, P; Lubatti, H J; Lueking, L; Luo, L; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A-M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; Mayorov, A A; McCarthy, R; McCroskey, R; Meder, D; Melnitchouk, A; Mendes, A; Mendoza, D; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Mitrevski, J; Molina, J; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mundim, L; Mutaf, Y D; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; Nurse, E; O'Dell, V; O'Neil, D C; Oguri, V; Oliveira, N; Oshima, N; Otero y Garzón, G J; Padley, P; Parashar, N; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Perez, E; Pétroff, P; Petteni, M; Piegaia, R; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Pompos, A; Pope, B G; Silva, W L Prado da; Prosper, H B

2005-10-21

340

Design and construction of a Vertex Chamber and measurement of the average B-Hadron lifetime  

SciTech Connect

Four parameters describe the mixing of the three quark generations in the Standard Model of the weak charged current interaction. These four parameters are experimental inputs to the model. A measurement of the mean lifetime of hadrons containing b-quarks, or B-Hadrons, constrains the magnitudes of two of these parameters. Measurement of the B-Hadron lifetime requires a device that can measure the locations of the stable particles that result from B-Hadron decay. This device must function reliably in an inaccessible location, and survive high radiation levels. We describe the design and construction of such a device, a gaseous drift chamber. Tubes of 6.9 mm diameter, having aluminized mylar walls of 100 ..mu..m thickness are utilized in this Vertex Chamber. It achieves a spatial resolution of 45 ..mu..m, and a resolution in extrapolation to the B-Hadron decay location of 87 ..mu..m. Its inner layer is 4.6 cm from e/sup +/e/sup -/ colliding beams. The Vertex Chamber is situated within the MAC detector at PEP. We have analyzed botht he 94 pb/sup -1/ of integrated luminosity accumulated at ..sqrt..s = 29 GeV with the Vertex Chamber in place as well as the 210 pb/sup -1/ accumulated previously. We require a lepton with large momentum transverse to the event thrust axis to obtain a sample of events enriched in B-Hadron decays. The distribution of signed impact parameters of all tracks in these events is used to measure the B-Hadron flight distance, and hence lifetime. 106 refs., 79 figs., 20 tabs.

Nelson, H.N.

1987-10-01

341

Inclusive measurements of inelastic electron and positron scattering from unpolarized hydrogen and deuterium targets  

NASA Astrophysics Data System (ADS)

Results of inclusive measurements of inelastic electron and positron scattering from unpolarized protons and deuterons at the HERMES experiment are presented. The structure functions F 2 p and F 2 d are determined using a parameterization of existing data for the longitudinal-to-transverse virtual-photon absorption cross-section ratio. The HERMES results provide data in the ranges 0.006 ? x ? 0.9 and 0.1 GeV2 ? Q 2 ? 20 GeV2, covering the transition region between the perturbative and the non-perturbative regimes of QCD in a so-far largely unexplored kinematic region. They are in agreement with existing world data in the region of overlap. The measured cross sections are used, in combination with data from other experiments, to perform fits to the photon-nucleon cross section using the functional form of the ALLM model. The deuteron-to-proton cross-section ratio is also determined.

Airapetian, A.; Akopov, N.; Akopov, Z.; Aschenauer, E. C.; Augustyniak, W.; Avakian, R.; Avetissian, A.; Avetisyan, E.; Belostotski, S.; Bianchi, N.; Blok, H. P.; Borissov, A.; Bowles, J.; Bryzgalov, V.; Burns, J.; Capiluppi, M.; Capitani, G. P.; Cisbani, E.; Ciullo, G.; Contalbrigo, M.; Dalpiaz, P. F.; Deconinck, W.; de Leo, R.; de Nardo, L.; de Sanctis, E.; Diefenthaler, M.; di Nezza, P.; Düren, M.; Ehrenfried, M.; Elbakian, G.; Ellinghaus, F.; Fabbri, R.; Fantoni, A.; Felawka, L.; Frullani, S.; Gabbert, D.; Gapienko, G.; Gapienko, V.; Garibaldi, F.; Gavrilov, G.; Gharibyan, V.; Giordano, F.; Gliske, S.; Golembiovskaya, M.; Hadjidakis, C.; Hartig, M.; Hasch, D.; Hill, G.; Hillenbrand, A.; Hoek, M.; Holler, Y.; Hristova, I.; Imazu, Y.; Ivanilov, A.; Jackson, H. E.; Jo, H. S.; Joosten, S.; Kaiser, R.; Karyan, G.; Keri, T.; Kinney, E.; Kisselev, A.; Korotkov, V.; Kozlov, V.; Kravchenko, P.; Krivokhijine, V. G.; Lagamba, L.; Lamb, R.; Lapikás, L.; Lehmann, I.; Lenisa, P.; Linden-Levy, L. A.; Ruiz, A. López; Lorenzon, W.; Lu, X.-G.; Lu, X.-R.; Ma, B.-Q.; Mahon, D.; Makins, N. C. R.; Manaenkov, S. I.; Manfré, L.; Mao, Y.; Marianski, B.; Martinez de La Ossa, A.; Marukyan, H.; Miller, C. A.; Miyachi, Y.; Movsisyan, A.; Muccifora, V.; Murray, M.; Mussgiller, A.; Nappi, E.; Naryshkin, Y.; Nass, A.; Negodaev, M.; Nowak, W.-D.; Pappalardo, L. L.; Perez-Benito, R.; Pickert, N.; Raithel, M.; Reimer, P. E.; Reolon, A. R.; Riedl, C.; Rith, K.; Rosner, G.; Rostomyan, A.; Rubin, J.; Ryckbosch, D.; Salomatin, Y.; Sanftl, F.; Schäfer, A.; Schnell, G.; Schüler, K. P.; Seitz, B.; Shibata, T.-A.; Shutov, V.; Stancari, M.; Statera, M.; Steffens, E.; Steijger, J. J. M.; Stenzel, H.; Stewart, J.; Stinzing, F.; Taroian, S.; Trzcinski, A.; Tytgat, M.; Vandenbroucke, A.; van Haarlem, Y.; van Hulse, C.; Veretennikov, D.; Vikhrov, V.; Vilardi, I.; Vogel, C.; Wang, S.; Yaschenko, S.; Ye, H.; Ye, Z.; Yen, S.; Yu, W.; Zeiler, D.; Zihlmann, B.; Zupranski, P.

2011-05-01

342

Beam-based age-momentum correlation studies of positronium spin conversion in paramagnetic solutions and of positron trapping at defects in diamonds  

Microsoft Academic Search

Correlated measurements of the lifetime and of the Doppler broadening of the 511 keV annihilation radiation of positrons (Age-Momentum Correlation, AMOC) using an MeV positron beam have become a powerful tool for investigating reactions of positrons or positronium as a function of time. The room-temperature reaction rate of the spin conversion of positronium in methanol induced by the presence of

H. Stoll; M. Koch; U. Lauff; K. Maier; J. Major; A. Seeger; P. Wesolowski; I. Billard; J. Ch. Abbe´; S. H. Connell; J. P. F. Sellschop; E. Sideras-Haddad; K. Bharuth-Ram; H. Haricharun

1994-01-01

343

Wet Chemical Surface Passivation of Germanium Wafers by Quinhydrone-Methanol Treatment for Minority Carrier Lifetime Measurements  

NASA Astrophysics Data System (ADS)

We have applied quinhydrone/methanol (Q/M) treatment to germanium (Ge) surfaces and shown that this treatment is also effective for passivating Ge surfaces for minority carrier lifetime measurements. Surface recombination velocity (S) of less than 20 cm/s has been obtained, which enables us to accurately evaluate the bulk lifetime of minority carriers, ?b, in Ge wafers. To the best of our knowledge, this is the first report on wet chemical treatment successfully applied to Ge surfaces achieving low values of S. The effects of quinhydrone concentration and passivation time on the results of lifetime measurements are described and discussed.

Swain, Bibhu P.; Takato, Hidetaka; Sakata, Isao

2009-10-01

344

Measurement of lifetimes and tensor polarizabilities of odd-parity states of atomic samarium  

SciTech Connect

A systematic measurement of the lifetimes and tensor polarizabilities of the lowest-lying odd-parity levels of Sm I was performed. The lifetimes were measured by detecting time-resolved fluorescence following pulsed-laser excitation of atoms in an atomic beam; polarizabilities were measured employing the method of Stark-induced quantum beats. An analysis of the data is undertaken to find the best even-parity candidate states for an atomic electric dipole moment (EDM) measurement. For the most favorable candidate state ({sup 7}G{sub 1}), the electron EDM enhancement factor is evaluated to be in the range {vert_bar}R{vert_bar}{approx}100{endash}3800. Critical analysis of the present data along with earlier results in Sm shows the necessity of a term reassignment for several odd-parity states. This term reassignment is also used in an estimate of the parity-nonconserving {sup 7}F{sub 0}{r_arrow}{sup 7}G{sub 1} amplitude. {copyright} {ital 1999} {ital The American Physical Society}

Rochester, S.; Bowers, C.J.; Budker, D. [Department of Physics, University of California at Berkeley, Berkeley, California 94720-7300 (United States)] [Department of Physics, University of California at Berkeley, Berkeley, California 94720-7300 (United States); Budker, D. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); DeMille, D. [Department of Physics, Yale University, New Haven, Connecticut 06520 (United States)] [Department of Physics, Yale University, New Haven, Connecticut 06520 (United States); Zolotorev, M. [Center for Beam Physics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Center for Beam Physics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

1999-05-01

345

Development of a Precision Neutron Lifetime Measurement: Magnetic Trapping of Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

The neutron lifetime plays an important role in both nuclear astrophysics and in furthering the understanding of weak interactions in the Standard Model. It is the most important experimental parameter in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. A precision measurement also provides a self consistency check of the unitarity of the CKM mixing matrix which relates the weak and mass eigenstates of quarks in the Standard Model. Our group has successfully demonstrated the trapping of ultracold neutrons in a conservative potential magnetic trap and demonstrated that the measured lifetime was consistent with the present world average value. This work represents a major upgrade of the apparatus assembled at the NIST Center for Neutron Research to address statistical limitations of the former measurement. Our unique approach to this measurement and the advantages it provides over other techniques will be discussed. The major systematics of the technique will be addressed. Tests of the upgrade components and details of the final stages of construction will also be presented.

O'Shaughnessy, Christopher Martin

346

Positron deep level transient spectroscopy — a new application of positron annihilation to semiconductor physics  

NASA Astrophysics Data System (ADS)

Recent positron mobility and lifetime measurements made on ac-biased metal on semi-insulating GaAs junctions, which have identified the native EL2 defect through a determination of the characteristic ionization energy of the donor level, are reviewed. It is shown that these measurements point towards a new spectroscopy, tentatively named positron-DLTS (deep level transient spectroscopy), that is the direct complement to conventional DLTS in that it monitors transients in the electric field of the depletion region rather than the inversely related depletion width, as deep levels undergo ionization. In this new spectroscopy, which may be applied to doped material by use of a suitable positron beam, electric field transients are monitored through the Doppler shift of the annihilation radiation resulting from the drift velocity of the positron in the depletion region. Two useful extensions of the new spectroscopy beyond conventional capacitance-DLTS are suggested. The first is that in some instances information on the microstructure of the defect causing the deep level may be inferred from the sensitivity of the positron to vacancy defects of negative and neutral charge states. The second is that the positron annihilation technique is intrinsically much faster than conventional DLTS with the capability of observing transients some 10 6 times faster, thus allowing deep levels (and even shallow levels) to be investigated without problems associated with carrier freeze-out.

Beling, C. D.; Fung, S.; Au, H. L.; Ling, C. C.; Reddy, C. V.; Deng, A. H.; Panda, B. K.

1997-05-01

347

Spectroscopy and Lifetime Measurements of Some N=3 and N=4 Levels of Hydrogen Molecule.  

NASA Astrophysics Data System (ADS)

A versatile laser-molecular beam method has been applied to the study of highly excited states of molecular hydrogen. A thermal beam of H(,2) was excited by electron bombardment to the lowest triplet excited state, which is metastable. Selective, Doppler-free excitation of higher states was accomplished by crossing the molecular beam transversely with the beam from a cw dye laser. The decay of the excited states can be detected by various means, depending upon the predominant decay channel. A photomultiplier was used to observe the decay of the 3s, 3d states in the vacuum ultraviolet. By externally chopping the laser into short pulses and using time-resolved detection, the excited state lifetimes can be measured directly. Measurements of 14 lifetimes in the 3s, 3d complex are reported, with typical accuracies of a few percent. The observed lifetimes range from 11.1 to 48.8 nsec. The apparatus was also used to make spectroscopic measurements of the triplet 4s and 4d states. Preliminary assignments are given for levels of the 4s state, which has not previously been observed. It was found that the v = 1 and v = 2 vibrational levels of 4s state or predissociate in less than 1 nsec. A Channeltron electron multiplier was used to detect the products of this predissociation. A simple theoretical model for Rydberg state structure was developed, and has been applied with considerable success to the optical structure of the 4d states. Future applications of the experimental method to the high Rydberg states of H(,2) and the excited states of N(,2) are discussed.

Eyler, Edward Eugene

348

Measurement of the branching fractions and lifetime of the 5 D5 /2 level of Ba+  

NASA Astrophysics Data System (ADS)

We present a measurement of the branching fractions for decay from the long-lived 5 D5 /2 level in 138Ba+. The branching fraction for decay into the 6 S1 /2 ground state was found to be 0.846 (25) stat(4) sys . We also report an improved measurement of the 5 D5 /2 lifetime, ?5 D5/2=31.2 (0.9 ) s. Together these measurements provide an experimental determination of transition rates for decay out of the 5 D5 /2 level. The low (<7 ×10-12 Torr) pressure in the ion trap in which these measurements were made simplified data acquisition and analysis. Comparison of the experimental results with theoretical predictions of the transition rates shows good agreement.

Auchter, Carolyn; Noel, Thomas W.; Hoffman, Matthew R.; Williams, Spencer R.; Blinov, Boris B.

2014-12-01

349

Lifetime measurements and dipole transition rates for superdeformed states in {sup 190}Hg.  

SciTech Connect

The Doppler-shift attenuation method was used to measure life-times of superdeformed (SD) states for both the yrast and the first excited superdeformed band of {sup 190}Hg. Intrinsic quadruple moments Q{sub 0} were extracted. For the first time, the dipole transition rates have been extracted for the inter-band transitions which connect the excited SD band to the yrast states in the second minimum. The results support the interpretation of the excited SD band as a rotational band built on an octupole vibration.

Amro, H.

1999-03-24

350

Measurement requirements and techniques for degradation studies and lifetime prediction testing of photovoltaic modules  

NASA Technical Reports Server (NTRS)

Tests of weathering and aging behavior are being developed to characterize the degradation and predict the lifetimes of low-cost photovoltaic arrays. Environmental factors which affect array performance include UV radiation, thermal energy, water, oxygen (generally involved in synergistic effects with UV radiation or high temperatures), physical stress, pollutants (oxides of nitrogen, sulfur dioxide and ozone), abrasives and dirt. A survey of photovoltaic array testing has shown the need to establish quantitative correlations between certain measurable properties (carbonyl formation, glass transition temperature, and molecular weight change) and modes of degradation and failure.

Noel, G. T.; Sliemers, F. A.; Derringer, G. C.; Wood, V. E.; Wilkes, K. E.; Gaines, G. B.; Carmichael, D. C.

1978-01-01

351

Lifetime measurements in neutron-rich 63,65Co isotopes using the AGATA demonstrator  

NASA Astrophysics Data System (ADS)

Lifetimes of the low-lying (11/2-) states in 63,65Co have been measured employing the recoil distance doppler shift method (RDDS) with the AGATA ?-ray array and the PRISMA mass spectrometer. These nuclei were populated via a multinucleon transfer reaction by bombarding a 238U target with a beam of 64Ni. The experimental B(E2) reduced transition probabilities for 63,65Co are well reproduced by large-scale shell-model calculations that predict a constant trend of the B(E2) values up to the N=40 67Co isotope.

Modamio, V.; Valiente-Dobón, J. J.; Lunardi, S.; Lenzi, S. M.; Gadea, A.; Mengoni, D.; Bazzacco, D.; Algora, A.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Bracco, A.; Bruyneel, B.; Bürger, A.; Chavas, J.; Corradi, L.; Crespi, F. C. L.; de Angelis, G.; Désesquelles, P.; de France, G.; Depalo, R.; Dewald, A.; Doncel, M.; Erduran, M. N.; Farnea, E.; Fioretto, E.; Fransen, Ch.; Geibel, K.; Gottardo, A.; Görgen, A.; Habermann, T.; Hackstein, M.; Hess, H.; Hüyük, T.; John, P. R.; Jolie, J.; Judson, D.; Jungclaus, A.; Karkour, N.; Kempley, R.; Leoni, S.; Melon, B.; Menegazzo, R.; Michelagnoli, C.; Mijatovi?, T.; Million, B.; Möller, O.; Montagnoli, G.; Montanari, D.; Nannini, A.; Napoli, D. R.; Podolyak, Zs.; Pollarolo, G.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Rosso, D.; Rother, W.; Sahin, E.; Salsac, M. D.; Scarlassara, F.; Sieja, K.; Söderström, P. A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Theisen, Ch.; Travers, B.; Ur, C. A.

2013-10-01

352

Differential lifetime measurements and identical superdeformed bands in {sup 192,194}Hg  

SciTech Connect

High-precision lifetime measurements have been performed in superdeformed (SD) bands of {sup 192,194}Hg with the Doppler-shift attenuation method. Intrinsic quadrupole moments Q{sub 0} were extracted for three SD bands in {sup 194}Hg and for the yrast SD band in {sup 192}Hg. Within experimental uncertainties, all four SD bands have equal Q{sub 0} values. These results provide constraints on differences in Q{sub 0} values between the {open_quotes}identical{close_quotes} SD bands {sup 194}Hg(3) and {sup 192}Hg(1). {copyright} {ital 1997} {ital The American Physical Society}

Moore, E.F.; Amro, H. [North Carolina State University, Raleigh, North Carolina 27695 (United States)] [North Carolina State University, Raleigh, North Carolina 27695 (United States); Lauritsen, T.; Janssens, R.V.; Khoo, T.L.; Ackermann, D.; Ahmad, I.; Amro, H.; Blumenthal, D.; Carpenter, M.P.; Fischer, S.M.; Hackman, G.; Nisius, D. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Hannachi, F.; Lopez-Martens, A. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, IN2P3-CNRS, bat 104-108, F-91405 Orsay (France)] [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, IN2P3-CNRS, bat 104-108, F-91405 Orsay (France); Korichi, A. [Institut de Physique Nucleaire, F-91406, Orsay Cedex (France)] [Institut de Physique Nucleaire, F-91406, Orsay Cedex (France); Asztalos, S.; Clark, R.M.; Deleplanque, M.A.; Diamond, R.M.; Fallon, P.; Lee, I.Y.; Macchiavelli, A.O.; Stephens, F.S. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Becker, J.A.; Bernstein, L.; Farris, L.P.; Henry, E.A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

1997-05-01

353

Measurement of Lifetime and Decay-Width Difference in Bs0-->J\\/psivarphi Decays  

Microsoft Academic Search

We measure the mean lifetime tau=2\\/(GammaL+GammaH) and the decay-width difference DeltaGamma=GammaL-GammaH of the light and heavy mass eigenstates of the Bs0 meson, BsL0 and BsH0, in Bs0-->J\\/psivarphi decays using 1.7fb-1 of data collected with the CDF II detector at the Fermilab Tevatron p pmacr collider. Assuming CP conservation, a good approximation for the Bs0 system in the standard model, we

T. Aaltonen; A. Abulencia; J. Adelman; T. Akimoto; M. G. Albrow; B. Álvarez González; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; A. Apresyan; T. Arisawa; A. Artikov; W. Ashmanskas; A. Attal; A. Aurisano; F. Azfar; P. Azzi-Bacchetta; P. Azzurri; N. Bacchetta; W. Badgett; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; S. Baroiant; V. Bartsch; G. Bauer; P.-H. Beauchemin; F. Bedeschi; P. Bednar; S. Behari; G. Bellettini; J. Bellinger; A. Belloni; D. Benjamin; A. Beretvas; J. Beringer; T. Berry; A. Bhatti; M. Binkley; D. Bisello; I. Bizjak; R. E. Blair; C. Blocker; B. Blumenfeld; A. Bocci; A. Bodek; V. Boisvert; G. Bolla; A. Bolshov; D. Bortoletto; J. Boudreau; A. Boveia; B. Brau; L. Brigliadori; C. Bromberg; E. Brubaker; J. Budagov; H. S. Budd; S. Budd; K. Burkett; G. Busetto; P. Bussey; A. Buzatu; K. L. Byrum; S. Cabrera; M. Campanelli; M. Campbell; F. Canelli; A. Canepa; D. Carlsmith; R. Carosi; S. Carrillo; S. Carron; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; M. Cavalli-Sforza; A. Cerri; L. Cerrito; S. H. Chang; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; F. Chlebana; K. Cho; D. Chokheli; J. P. Chou; G. Choudalakis; S. H. Chuang; K. Chung; W. H. Chung; Y. S. Chung; C. I. Ciobanu; M. A. Ciocci; A. Clark; D. Clark; G. Compostella; M. E. Convery; J. Conway; B. Cooper; K. Copic; M. Cordelli; G. Cortiana; F. Crescioli; C. Cuenca Almenar; J. Cuevas; R. Culbertson; J. C. Cully; D. Dagenhart; M. Datta; T. Davies; P. de Barbaro; S. de Cecco; A. Deisher; G. de Lentdecker; G. de Lorenzo; M. Dell'Orso; L. Demortier; J. Deng; M. Deninno; D. de Pedis; P. F. Derwent; G. P. di Giovanni; C. Dionisi; B. di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; P. Dong; J. Donini; T. Dorigo; S. Dube; J. Efron; R. Erbacher; D. Errede; S. Errede; R. Eusebi; H. C. Fang; S. Farrington; W. T. Fedorko; R. G. Feild; M. Feindt; J. P. Fernandez; C. Ferrazza; R. Field; G. Flanagan; R. Forrest; S. Forrester; M. Franklin; J. C. Freeman; I. Furic; M. Gallinaro; J. Galyardt; F. Garberson; J. E. Garcia; A. F. Garfinkel; H. Gerberich; D. Gerdes; S. Giagu; P. Giannetti; K. Gibson; J. L. Gimmell; C. M. Ginsburg; N. Giokaris; M. Giordani; P. Giromini; M. Giunta; V. Glagolev; D. Glenzinski; M. Gold; N. Goldschmidt; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González; I. Gorelov; A. T. Goshaw; K. Goulianos; A. Gresele; S. Grinstein; C. Grosso-Pilcher; U. Grundler; J. Guimaraes da Costa; Z. Gunay-Unalan; C. Haber; K. Hahn; S. R. Hahn; E. Halkiadakis; B.-Y. Han; J. Y. Han; R. Handler; F. Happacher; K. Hara; D. Hare; M. Hare; S. Harper; R. F. Harr; R. M. Harris; M. Hartz; K. Hatakeyama; J. Hauser; C. Hays; M. Heck; A. Heijboer; B. Heinemann; J. Heinrich; C. Henderson; M. Herndon; J. Heuser; S. Hewamanage; D. Hidas; C. S. Hill; D. Hirschbuehl; A. Hocker; S. Hou; M. Houlden; S.-C. Hsu; B. T. Huffman; R. E. Hughes; U. Husemann; J. Huston; J. Incandela; G. Introzzi; M. Iori; A. Ivanov; B. Iyutin; E. James; B. Jayatilaka; D. Jeans; E. J. Jeon; S. Jindariani; W. Johnson; M. Jones; K. K. Joo; S. Y. Jun; J. E. Jung; T. R. Junk; T. Kamon; D. Kar; P. E. Karchin; Y. Kato; R. Kephart; U. Kerzel; V. Khotilovich; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; N. Kimura; L. Kirsch; S. Klimenko; M. Klute; B. Knuteson; B. R. Ko; S. A. Koay; K. Kondo; D. J. Kong; J. Konigsberg; A. Korytov; A. V. Kotwal; J. Kraus; M. Kreps; J. Kroll; N. Krumnack; M. Kruse; V. Krutelyov; T. Kubo; S. E. Kuhlmann; T. Kuhr; N. P. Kulkarni; Y. Kusakabe; S. Kwang; A. T. Laasanen; S. Lai; S. Lami; S. Lammel; M. Lancaster; R. L. Lander; K. Lannon; A. Lath; G. Latino; I. Lazzizzera; T. Lecompte; J. Lee; Y. J. Lee; S. W. Lee; R. Lefèvre; N. Leonardo; S. Leone; S. Levy; J. D. Lewis; C. S. Lin; M. Lindgren; E. Lipeles; A. Lister; D. O. Litvintsev; T. Liu; N. S. Lockyer; A. Loginov; M. Loreti; L. Lovas; R.-S. Lu; D. Lucchesi; J. Lueck; C. Luci; P. Lujan; P. Lukens; G. Lungu; L. Lyons; J. Lys; R. Lysak; E. Lytken; P. Mack; D. MacQueen; R. Madrak; K. Maeshima; K. Makhoul; T. Maki; P. Maksimovic; S. Malde; S. Malik; G. Manca; A. Manousakis; F. Margaroli; C. Marino; A. Martin; M. Martin; V. Martin; M. Martínez; R. Martínez-Ballarín; T. Maruyama; P. Mastrandrea; T. Masubuchi; M. E. Mattson; P. Mazzanti; K. S. McFarland; P. McIntyre; R. McNulty; A. Mehta; P. Mehtala; S. Menzemer; A. Menzione; P. Merkel; C. Mesropian; A. Messina; T. Miao; N. Miladinovic; J. Miles; R. Miller; C. Mills; M. Milnik; A. Mitra; G. Mitselmakher; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. Morello; P. Movilla Fernandez; J. Mülmenstädt; A. Mukherjee; Th. Muller; R. Mumford; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; A. Nagano; J. Naganoma; K. Nakamura; I. Nakano; A. Napier; V. Necula; C. Neu; M. S. Neubauer; J. Nielsen; L. Nodulman; M. Norman; O. Norniella; E. Nurse; S. H. Oh

2008-01-01

354

Measurement of lifetime and decay-width difference in BS(0)-> J\\/psi phi decays  

Microsoft Academic Search

We measure the mean lifetime tau=2\\/(Gamma(L)+Gamma(H)) and the decay-width difference Delta Gamma=Gamma(L)-Gamma(H) of the light and heavy mass eigenstates of the B-s(0) meson, B-sL(0) and B-sH(0), in B-s(0)-> J\\/psi phi decays using 1.7 fb(-1) of data collected with the CDF II detector at the Fermilab Tevatron pp collider. Assuming CP conservation, a good approximation for the B-s(0) system in the

T. Aaltonen; A. Abulencia; J. Adelman; T. Akimoto; M. G. Albrow; B. A. Gonzalez; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; A. Apresyan; T. Arisawa; A. Artikov; W. Ashmanskas; A. Attal; A. Aurisano; F. Azfar; P. Azzi-Bacchetta; P. Azzurri; N. Bacchetta; W. Badgett; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; S. Baroiant; V. Bartsch; G. Bauer; P. H. Beauchemin; F. Bedeschi; P. Bednar; S. Behari; G. Bellettini; J. Bellinger; A. Belloni; D. Benjamin; A. Beretvas; J. Beringer; T. Berry; A. Bhatti; M. Binkley; D. Bisello; I. Bizjak; R. E. Blair; C. Blocker; B. Blumenfeld; A. Bocci; A. Bodek; V. Boisvert; G. Bolla; A. Bolshov; D. Bortoletto; J. Boudreau; A. Boveia; B. Brau; L. Brigliadori; C. Bromberg; E. Brubaker; J. Budagov; H. S. Budd; S. Budd; K. Burkett; G. Busetto; P. Bussey; A. Buzatu; K. L. Byrum; S. Cabrera; M. Campanelli; M. Campbell; F. Canelli; A. Canepa; D. Carlsmith; R. Carosi; S. Carrillo; S. Carron; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; M. Cavalli-Sforza; A. Cerri; L. Cerrito; S. H. Chang; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; F. Chlebana; K. Cho; D. Chokheli; J. P. Chou; G. Choudalakis; S. H. Chuang; K. Chung; W. H. Chung; Y. S. Chung; C. I. Ciobanu; M. A. Ciocci; A. Clark; D. Clark; G. Compostella; M. E. Convery; J. Conway; B. Cooper; K. Copic; M. Cordelli; G. Cortiana; F. Crescioli; C. C. Almenar; J. Cuevas; R. Culbertson; J. C. Cully; D. Dagenhart; M. Datta; T. Davies; P. de Barbaro; S. De Cecco; A. Deisher; G. De Lentdecker; G. De Lorenzo; M. DellOrso; L. Demortier; J. Deng; M. Deninno; D. De Pedis; P. F. Derwent; G. P. Di Giovanni; C. Dionisi; B. Di Ruzza; J. R. Dittmann; M. DOnofrio; S. Donati; P. Dong; J. Donini; T. Dorigo; S. Dube; J. Efron; R. Erbacher; D. Errede; S. Errede; R. Eusebi; H. C. Fang; S. Farrington; W. T. Fedorko; R. G. Feild; M. Feindt; J. P. Fernandez; C. Ferrazza; R. Field; G. Flanagan; R. Forrest; S. Forrester; M. Franklin; J. C. Freeman; I. Furic; M. Gallinaro; J. Galyardt; F. Garberson; J. E. Garcia; A. F. Garfinkel; H. Gerberich; D. Gerdes; S. Giagu; P. Giannetti; K. Gibson; J. L. Gimmell; C. M. Ginsburg; N. Giokaris; M. Giordani; P. Giromini; M. Giunta; V. Glagolev; D. Glenzinski; M. Gold; N. Goldschmidt; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. Gonzalez; I. Gorelov; A. T. Goshaw; K. Goulianos; A. Gresele; S. Grinstein; C. Grosso-Pilcher; U. Grundler; J. G. da Costa; Z. Gunay-Unalan; C. Haber; K. Hahn; S. R. Hahn; E. Halkiadakis; B. Y. Han; J. Y. Han; R. Handler; F. Happacher; K. Hara; D. Hare; M. Hare; S. Harper; R. F. Harr; R. M. Harris; M. Hartz; K. Hatakeyama; J. Hauser; C. Hays; M. Heck; A. Heijboer; B. Heinemann; J. Heinrich; C. Henderson; M. Herndon; J. Heuser; S. Hewamanage; D. Hidas; C. S. Hill; D. Hirschbuehl; A. Hocker; S. Hou; M. Houlden; S. C. Hsu; B. T. Huffman; R. E. Hughes; U. Husemann; J. Huston; J. Incandela; G. Introzzi; M. Iori; A. Ivanov; B. Iyutin; E. James; B. Jayatilaka; D. Jeans; E. J. Jeon; S. Jindariani; W. Johnson; M. Jones; K. K. Joo; S. Y. Jun; J. E. Jung; T. R. Junk; T. Kamon; D. Kar; P. E. Karchin; Y. Kato; R. Kephart; U. Kerzel; V. Khotilovich; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; N. Kimura; L. Kirsch; S. Klimenko; M. Klute; B. Knuteson; B. R. Ko; S. A. Koay; K. Kondo; D. J. Kong; J. Konigsberg; A. Korytov; A. V. Kotwal; J. Kraus; M. Kreps; J. Kroll; N. Krumnack; M. Kruse; V. Krutelyov; T. Kubo; S. E. Kuhlmann; T. Kuhr; N. P. Kulkarni; Y. Kusakabe; S. Kwang; A. T. Laasanen; S. Lai; S. Lami; S. Lammel; M. Lancaster; R. L. Lander; K. Lannon; A. Lath; G. Latino; I. Lazzizzera; T. LeCompte; J. Lee; Y. J. Lee; S. W. Lee; R. Lefevre; N. Leonardo; S. Leone; S. Levy; J. D. Lewis; C. Lin; M. Lindgren; E. Lipeles; A. Lister; D. O. Litvintsev; T. Liu; N. S. Lockyer; A. Loginov; M. Loreti; L. Lovas; R. S. Lu; D. Lucchesi; J. Lueck; C. Luci; P. Lujan; P. Lukens; G. Lungu; L. Lyons; J. Lys; R. Lysak; E. Lytken; P. Mack; D. MacQueen; R. Madrak; K. Maeshima; K. Makhoul; T. Maki; P. Maksimovic; S. Malde; S. Malik; G. Manca; A. Manousakis; F. Margaroli; C. Marino; A. Martin; M. Martin; V. Martin; M. Martinez; R. Martinez-Ballarin; T. Maruyama; P. Mastrandrea; T. Masubuchi; M. E. Mattson; P. Mazzanti; K. S. McFarland; P. McIntyre; R. McNulty; A. Mehta; P. Mehtala; S. Menzemer; A. Menzione; P. Merkel; C. Mesropian; A. Messina; T. Miao; N. Miladinovic; J. Miles; R. Miller; C. Mills; M. Milnik; A. Mitra; G. Mitselmakher; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. Morello; P. M. Fernandez; J. Mulmenstadt; A. Mukherjee; T. Muller; R. Mumford; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; A. Nagano; J. Naganoma; K. Nakamura; I. Nakano; A. Napier; V. Necula; C. Neu; M. S. Neubauer; J. Nielsen; L. Nodulman; M. Norman; O. Norniella; E. Nurse; S. H. Oh; Y. D. Oh; I. Oksuzian; T. Okusawa; R. Oldeman

2008-01-01

355

Measured lifetimes of metastable levels of Mn X, Mn XI, Mn XII, and Mn XIII ions  

E-print Network

. The measured lifetimes are tau(Mn X, 3s(2)3p(4) S-1(0)) = 2.1 +/- 0.3, tau(Mn X, 3s(2)3p(4) D-1(2)) = 18.02 +/- 0.16, tau(Mn XI, 3s(2)3p(3) P-2(3/2)) = 3.0 +/- 0.2, tau(Mn XI, 3s(2)3p(3) P-2(1/2)) = 6.17 +/- 0.29, tau(Mn XI, 3s(2)3p(3) D-2(3/2)) = 35.1 +/- 1...

Moehs, D. P.; Church, David A.

1999-01-01

356

Muon Lifetime Measurement and Introduction to the use of FPGAs in Experimental Physics  

SciTech Connect

During the laboratory sessions at the Workshop, the students used a simple experimental setup to measure the muon lifetime with a 10% statistical error. The muon detector consisted of a sealed container, filled with liquid scintillator, coupled to a 2.5'' photomultiplier (PMT). A personal computer (PC) was used to control a digital oscilloscope which directly measured the time interval between two consecutive PMT pulses in a time window of 20 {mu}s. The students were also introduced to the use of root to analyze the muon data and to measure the muon lifetime. They were also presented with a basic introduction to the application of field-programmable gate arrays (FPGAs) in data acquisition (DAQ) systems by means of examples. We started with a brief introduction to the VHDL language and the software package used to program FPGAs and PROMs on a commercial FPGA development board. They learned to program FPGAs for handling data transfers using the RS-232 port of a PC. They were also introduced to the concepts of circular RAMs (Random Access Memory) and FIFO (First-In First-Out) memories in the context of fast and efficient DAQ systems. We emphasized the way in which inexpensive FPGA-based electronics replaces the use of traditionally used electronics modules, such as NIM, CAMAC, FASTBUS, VME, etc., to construct fast and powerful DAQ systems.

Villasenor, L. [Instituto de Fisica y Matematicas, Universidad Michoacana de San Nicolas de Hidalgo. Apartado Postal 2-82, C.P. 58040, Morelia, Mich. (Mexico)

2008-07-02

357

Muon Lifetime Measurement and Introduction to the use of FPGAs in Experimental Physics  

NASA Astrophysics Data System (ADS)

During the laboratory sessions at the Workshop, the students used a simple experimental setup to measure the muon lifetime with a 10% statistical error. The muon detector consisted of a sealed container, filled with liquid scintillator, coupled to a 2.5? photomultiplier (PMT). A personal computer (PC) was used to control a digital oscilloscope which directly measured the time interval between two consecutive PMT pulses in a time window of 20 ?s. The students were also introduced to the use of root to analyze the muon data and to measure the muon lifetime. They were also presented with a basic introduction to the application of field-programmable gate arrays (FPGAs) in data acquisition (DAQ) systems by means of examples. We started with a brief introduction to the VHDL language and the software package used to program FPGAs and PROMs on a commercial FPGA development board. They learned to program FPGAs for handling data transfers using the RS-232 port of a PC. They were also introduced to the concepts of circular RAMs (Random Access Memory) and FIFO (First-In First-Out) memories in the context of fast and efficient DAQ systems. We emphasized the way in which inexpensive FPGA-based electronics replaces the use of traditionally used electronics modules, such as NIM, CAMAC, FASTBUS, VME, etc., to construct fast and powerful DAQ systems.

Villaseñor, L.

2008-07-01

358

A measurement of the lambda_b lifetime at the D0 experiment  

SciTech Connect

This thesis describes a measurement of the lifetime of the {Lambda}{sub b}{sup 0} baryon, performed using data from proton-antiproton collisions at a centre of mass energy of 1.96 TeV. The decay {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{mu}{sup -}{ovr P{nu}}{sub {mu}}X was reconstructed in approximately 1.3 fb{sup -1} of data recorded by the D0 detector in 2002-2006 during Run II of the Fermilab Tevatron collider. A signal of 4437 {+-} 329 {Lambda}{sub c}{sup +}{mu}{sup -} pairs was obtained, and the {Lambda}{sub b}{sup 0} lifetime was measured using a binned {chi}{sup 2} fit, which gives a value {tau}({Lambda}{sub b}{sup 0}) = 1.290{sub -0.110}{sup +0.119}(stat){sub -0.091}{sup +0.085}(syst) ps. This result is consistent with the world average and is one of the most precise measurements of this quantity.

Lewin, Marcus Philip; /Lancaster U.

2007-07-01

359

In Vivo Mitochondrial Oxygen Tension Measured by a Delayed Fluorescence Lifetime Technique  

PubMed Central

Mitochondrial oxygen tension (mitoPO2) is a key parameter for cellular function, which is considered to be affected under various pathophysiological circumstances. Although many techniques for assessing in vivo oxygenation are available, no technique for measuring mitoPO2 in vivo exists. Here we report in vivo measurement of mitoPO2 and the recovery of mitoPO2 histograms in rat liver by a novel optical technique under normal and pathological circumstances. The technique is based on oxygen-dependent quenching of the delayed fluorescence lifetime of protoporphyrin IX. Application of 5-aminolevulinic acid enhanced mitochondrial protoporphyrin IX levels and induced oxygen-dependent delayed fluorescence in various tissues, without affecting mitochondrial respiration. Using fluorescence microscopy, we demonstrate in isolated hepatocytes that the signal is of mitochondrial origin. The delayed fluorescence lifetime was calibrated in isolated hepatocytes and isolated perfused livers. Ultimately, the technique was applied to measure mitoPO2 in rat liver in vivo. The results demonstrate mitoPO2 values of ?30–40 mmHg. mitoPO2 was highly sensitive to small changes in inspired oxygen concentration around atmospheric oxygen level. Ischemia-reperfusion interventions showed altered mitoPO2 distribution, which flattened overall compared to baseline conditions. The reported technology is scalable from microscopic to macroscopic applications, and its reliance on an endogenous compound greatly enhances its potential field of applications. PMID:18641065

Mik, Egbert G.; Johannes, Tanja; Zuurbier, Coert J.; Heinen, Andre; Houben-Weerts, Judith H. P. M.; Balestra, Gianmarco M.; Stap, Jan; Beek, Johan F.; Ince, Can

2008-01-01

360

Temperature dependence of positron trapping at grain boundaries  

NASA Astrophysics Data System (ADS)

Positron lifetime spectra were measured for fine-grained samples of the superplastic alloy Al - 5 wt% Ca - 5 wt% Zn at temperatures from 10 to 295 K. The lifetime attributed to annihilation from traps at the grain interfaces was found to increase with the temperature, while the corresponding intensity was observed to decrease. The quantitative analysis of the experimental results according to the diffusion-trapping model (Dupasquier et al 1993 Phys. Rev. B 48 9235) leads to the following conclusions: (a) the positron diffusion coefficient in the alloy matrix (a solid solution of Zn and Ca in Al) is limited by positron - phonon scattering as well as by positron - impurity interaction; (b) the phonon-associated term in the reciprocal of the diffusion coefficient is dominant at room temperature and scales at other temperatures with the same power law as holds for pure Al (Soininen et al 1990 Phys. Rev. B 41 6277); (c) the term associated with positron - impurity scattering is small except at very low temperatures, but the positron - impurity interaction seems to give a localization effect that is more important than the scattering; and (d) the specific trapping rate at the interface has a negative temperature dependence, as expected for trapping mediated by a precursor shallow state.

Aina, S.; Dupasquier, A.; Folegati, P.; DeDiego, N.; del Rio, J.; Somoza, A.; Valli, M.

1997-08-01

361

High-resolution positron Q-value measurements and nuclear-structure studies far from the stability line. Progress report  

SciTech Connect

Extensive data analysis and theoretical analysis has been done to complete the extensive decay scheme investigation of /sup 206/ /sup 208/Fr and the level structures of /sup 206/ /sup 208/Rn. A final version of a journal article is presented in preprint form. Extensive Monte Carlo calculations have been made to correct the end point energies of positron spectra taken with intrinsic Ge detectors for annihilation radiation interferences. These calculations were tested using the decay of /sup 82/Sr which has previously measured positron branches. This technique was applied to the positron spectra collected at the on-line UNISOR isotope separator. The reactions used were /sup 60/Ni(/sup 20/Ne;p2n)/sup 77/Rb and /sup 60/Ni(/sup 20/Ne;pn)/sup 78/Rb. Values for 5, ..gamma..-..beta../sup +/ coincidence positron end point energies are given for the decay of /sup 77/Rb. The implied Q-value is 5.075 +- 0.010 MeV. A complete paper on the calculated corrections is presented. A flow chart of a more complete program which accounts for positrons scattering out of the detector and for bremsstralung radiation is also presented. End-point energies of four ..beta../sup +/ branches in /sup 77/Rb are given as well as a proposed energy level scheme of /sup 75/Kr based on ..gamma..-..gamma.. coincidence data taken at UNISOR.

Avignone, F.T. III.

1981-02-28

362

Measurement of the mean lifetimes of low spin states in the superdeformed band in133Nd  

NASA Astrophysics Data System (ADS)

The mean lifetimes of the lower spin states of the superdeformed band in133Nd have been measured with the coincidence recoil distance method. The reaction used to populate the band was105Pd (32S, 2p2n)133Nd at a beam energy of 152 MeV, and the gamma-rays were detected with the POLYTESSA array. The differential decay curve method was used to analyse the data and transition quadrupole moments, Q 0, were extracted from the measured lifetimes. The results obtained from the three lowest transitions in the superdeformed band are: Q 0=6.3±0.9 eb (21+/2?17+/2), Q 0=6.7±1.1 eb (25+/2?21+/2) and Q 0>5.0 eb (29+/2?25+/2). These results are consistent with previous results for the high spin members of the band, and are compared to theoretical calculations of total routhian surfaces. The calculation of reduced transition probabilities for the transitions that feed out of the band, allows the effect of hindrance due to K-forbiddenness to be investigated.

Forbes, S. A.; Böhm, G.; Clark, R. M.; Dewald, A.; Krücken, R.; Mullins, S. M.; Nolan, P. J.; Regan, P. H.; Wadsworth, R.

1995-03-01

363

A new differentially pumped plunger device to measure excited-state lifetimes in proton emitting nuclei  

NASA Astrophysics Data System (ADS)

A new plunger device has been designed and built to measure the lifetimes of unbound states in exotic nuclei beyond the proton drip-line. The device has been designed to work in both vacuum and dilute-gas environments made possible through the introduction of a low-voltage stepping motor. DPUNS will be used in conjunction with the gas-filled separator RITU and the vacuum separator MARA at the accelerator laboratory of the University of Jyväskylä, Finland, to measure the lifetimes of excited states with low population cross-sections. This is achieved by eliminating the need for a carbon foil to isolate the helium gas of RITU from the beam line thus reducing the background from beam-foil reactions. The inclusion of a high-sampling rate data acquisition card increases further the sensitivity of the device. The plunger will be used to address many key facets of nuclear structure physics with particular emphasis on the effect of deformation on proton emission rates.

Taylor, M. J.; Cullen, D. M.; Smith, A. J.; McFarlane, A.; Twist, V.; Alharshan, G. A.; Procter, M. G.; Braunroth, T.; Dewald, A.; Ellinger, E.; Fransen, C.; Butler, P. A.; Scheck, M.; Joss, D. T.; Saygi, B.; McPeake, C. G.; Grahn, T.; Greenlees, P. T.; Jakobsson, U.; Jones, P.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nieminen, P.; Pakarinen, J.; Peura, P.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J.

2013-04-01

364

Lifetime Measurements of the Positive D Meson, Positive F Meson and Positive Hyperon  

NASA Astrophysics Data System (ADS)

A hybrid emulsion-spectrometer experiment (E531) was performed in the wide-band neutrino beam line at the Fermi National Accelerator Laboratory in Batavia, Illinois, U.S.A. The primary purpose of this experiment was to measure the lifetimes of weakly-decaying, charmed particles. 1248 neutrino and antineutrino interactions were located of which 23 were reconstructed as charged, charmed candidates. From these 23 events the lifetime of the D('+) meson was determined to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). of the F('+) meson to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). and of the (LAMDA)(,c)('+) baryon to be. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). The mass of the F('+) meson is measured to be 2057 (+OR-) 39 MeV/c('2). Candidates for the decays (SIGMA)(,c) (--->) (LAMDA)(,c)('+)(pi), (SIGMA)(,c)('*) (--->) (LAMDA)(,c)('+)(pi), D('+*) (-- ->) D('+)(pi)('0), and F* (--->) F(gamma) are also observed.

Pitman, Dale Barbara

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Mean lifetime measurements of HeH{sup 2+}(2{ital p}{sigma}) isotopes  

SciTech Connect

The HeH{sup 2+} molecular ion decays by an electronic dipole transition from its bound first excited state (2{ital p}{sigma}) to the repulsive ground state (1{ital s}{sigma}). We have calculated the mean lifetimes of the vibrational states of a few HeH{sup 2+} isotopes and found a large isotopic effect, in particular for highly excited vibrational states, i.e., states with the same {ital v} have different decay rates. The measured decay curves of {sup 4}HeH{sup 2+}, {sup 3}HeD{sup 2+}, and {sup 4}HeD{sup 2+} ( i.e., the number of HeH{sup 2+} molecular ions as a function of their flight time from the target cell where they were formed), in contrast, are similar to each other. The lack of a measurable isotopic effect is related to the HeH{sup 2+} creation mechanism. In the charge-stripping collisions, a distribution of vibrational states is populated by vertical transitions and is thus centered around roughly the same vibrational energy and not around the same quantum number {ital v}. The mean lifetimes of the different isotopes as a function of their energy are surprisingly similar to each other, therefore washing out the isotopic effect. {copyright} {ital 1996 The American Physical Society.}

Ben-Itzhak, I.; Bouhnik, J.P.; Esry, B.D.; Gertner, I.; Heber, O.; Rosner, B. [James R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States)] [James R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States); [Department of Physics, Technion, Haifa 32000 (Israel); [JILA, Department of Physics, University of Colorado, Boulder, Colorado 80309 (United States); [Department of Particle Physics, Weizmann Institute of Science, Rehovot 76100 (Israel)

1996-07-01