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1

Positron lifetime measurements by proton capture  

NASA Astrophysics Data System (ADS)

A positron lifetime spectroscopy (PLS) technique was developed using coincident ? rays induced by proton capture. Proton capture in some light elements induce coincident MeV ? rays, allowing positron lifetime to be measured. One ? quantum provides a start signal for the positron lifetime spectrometer, whereas the other ? quantum bombards the sample under investigation, generating a positron inside it through pair production. The stop signal is obtained from the detection of one of the two 511 keV photons emitted from positron annihilation with the sample electrons. This new technique can extend PLS, which is a powerful tool to identify the size and concentration of defects, to thick materials and a broad range of applications. It also eliminates the source contribution from the measured spectra, which may lead to the identification of more defect types in a sample.

Selim, F. A.; Wells, D. P.; Harmon, J. F.

2005-03-01

2

Positron annihilation lifetime measurements of He-ion-irradiated Fe using pulsed positron beam  

NASA Astrophysics Data System (ADS)

The positron annihilation lifetimes of He-ion-irradiated Fe samples were measured by a pulsed positron beam technique. The relative thickness of the surface oxidation layer was measured by Auger microprobe measurements. Unirradiated samples with different surface oxidation layer thicknesses had very similar second lifetime component intensities, indicating that the surface oxidation layer thickness does not affect positron lifetime spectra. In lifetime measurements using 10-keV positrons, the second lifetime component decreased monotonically with increasing irradiation dose. The mean lifetime in the 10-keV measurements was longer than that in 15-keV measurements (which correspond to the peak region of vacancy production); this is thought to be due to vacancy clusters absorbing He atoms.

Sato, K.; Kinomura, A.; Omura, T.; Xu, Q.; Yoshiie, T.; Kasada, R.; Kimura, A.; Morishita, K.

2011-01-01

3

Nondestructive positron-lifetime measurements during fatigue of austenitic stainless steel using a mobile positron beam  

NASA Astrophysics Data System (ADS)

Nondestructive positron-lifetime measurements have been performed during stress-controlled symmetric fatigue of austenitic stainless steel up to failure for different applied stress amplitudes between 230 and 300 MPa. For this purpose a fatigue machine has been equipped with a mobile positron beam emitted from a 22 ?Ci (0.8 MBq) 72Se/72As generator. A pronounced increase of the mean positron lifetime has been found within the first 10% of fatigue life. Saturation has been reached after 40% of fatigue life. The mean positron lifetime at failure depends strongly on the applied stress amplitude.

Barbieri, Andrea; Hansen-Ilzhöfer, Sabine; Ilzhöfer, Achim; Holzwarth, Uwe

2000-09-01

4

Positron Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

We have assembled a positron lifetime spectrometer using two scintillation detectors in a slow-fast coincidence configuration. The decay of ^22Na serves as a convenient source of positrons. Positron energies are sufficiently high that positrons penetrate into the bulk of the surrounding material under study. A 1275 keV gamma ray emitted less than 10 ps following the positron decay serves as the lifetime start signal, while the detection of a 511 keV annihilation gamma signals the end of life of the positron. The first version of our spectrometer employs NaI scintillators that have good detection efficiencies but with time resolution of several nanoseconds are not particularly suitable for measuring sub-nanosecond lifetimes of positrons in metals. Recently we have replaced the NaI detectors with ones employing plastic scintillators, which offer a time resolution of better than 1 ns. First results of measurements performed with this apparatus will be discussed.

Martin, Jacob; Jaeger, Herbert

2010-04-01

5

Optimization of the Scintillator Size for Positron Lifetime Measurements  

NASA Astrophysics Data System (ADS)

Optimization of the measurement condition for positron annihilation lifetime spectroscopy (PALS) is discussed from the viewpoint of non-destructive "on-site" material inspection. Numerical analysis based on a least-squares estimation and experiments with various sizes of BaF2 scintillators by conventional PALS suggested that the use of relatively large BaF2 scintillators enables on-site material inspection by PALS with reasonable accumulation time and time resolution.

Yamawaki, M.; Kobayashi, Y.; Hattori, K.; Watanabe, Y.

2013-06-01

6

Measurement and Analysis of the Positron Annihilation Lifetime Spectra for Mesoporous Silica  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy as a technique of porous materials investigation is still under development. Both measurement conditions and lifetime spectra analysis methods have to be adapted to the requirements of positron porosimetry. If complex positron annihilation lifetime spectra of porous materials are processed, numerical methods of lifetime spectra analysis have to be used with a particular care. Among various methods of positron annihilation lifetime spectra analysis available, the most popular ones were tested implemented in programs MELT and LT. It was found, from the simulated spectra study, that a large number of counts in a spectrum is needed to obtain reliable results of analysis. Even then only an approximate solution is available. Determination of the approximation nature helps in a further interpretation of the results and in positron annihilation lifetime spectrometer setting adequate to the problem. For this purpose, a few complex spectra obtained from positron beam facility were tested. The results show a negligible influence of resolution function on long lifetime components, while the precise estimation of the background level is crucial. Also some distortions caused by imperfection of numerical analysis methods are pointed out.

Zaleski, R.

2006-11-01

7

Low-temperature positron lifetime and Doppler-broadening measurements for single-crystal nickel oxide containing cation vacancies  

SciTech Connect

Lifetime and Doppler-broadening measurements for positron annihilation in substoichiometric nickelous oxide have been made concomitantly from liquid-helium to room temperature. The concentration of cation vacancies is readily controlled by altering the ambient oxygen pressure while annealing the crystals at 1673/sup 0/K. It was found that neither of the three lifetimes observed or their relative intensities varied significantly with the oxygen pressure, and the bulk rate only increased slightly when the specimen was cooled from room to liquid-helium temperatures. These results are interpreted as indicating that some of the positrons are trapped by the existing cation vacancies and a smaller fraction by vacancy clusters.

Waber, J.T.; Snead, C.L. Jr.; Lynn, K.G.

1985-01-01

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

High-temperature vacant lattice site formation in solids and free volumes in melts studied by positron lifetime measurements  

Microsoft Academic Search

In the present paper a concise review is given of the application of positron lifetime measurements to the study of high-temperature vacancies in intermetallic compounds (F76.3Al23.7), in metal oxides (NiO), in elemental semiconductors (Si, Ge), and of the oxygen loss or uptake in YBa2Cu3O7-delta. Investigations of free volumes in elemental melts (Al, In, Ge) are included.

H.-E. Schaefer

1991-01-01

10

Positron lifetime in neutron-irradiated germanium  

SciTech Connect

A model is proposed for calculating the average positron lifetime (before annihilation) in the case when positrons are captured by traps of two types. The average positron lifetime calculated from the experimentally determined angular correlation of the annihilation ..gamma.. rays increases during stage I of isochronous annealing of neutron-irradiated germanium and decreases during stage II to the value before irradiation. The experimental and calculated dependences of the average positron lifetime on the annealing temperature are in qualitative agreement. The observed narrowing of the angular correlation curves and increase in the positron lifetime in neutron-irradiated germanium are inversely proportional to one another. A combined analysis of the annihilation, electrical, and x-ray experiments shows that during annealing of neutron-irradiated germanium the process of positron annihilation is influenced by two types of positron-sensitive defects, which are formed by irradiation (mainly disordered regions) and during stage I of the annealing process (probably divacancies).

Arifov, P.U.; Arutyunov, N.Y.

1980-02-01

11

Free-Radical Quenching of Positron Lifetimes  

Microsoft Academic Search

The annihilation lifetime of positrons stopping in benzene has been measured as a function of the percentage of added free radical, diphenylpicrylhydrazyl. The long component of the complex annihilation curve quenches from 2.67×10-9 sec in pure benzene to 5.3×10-10 sec at a 3% free radical concentration. An annihilation model following Bell and Graham's assumptions is discussed, postulating the partial formation

Stephan Berko; A. Joseph Zuchelli

1956-01-01

12

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

13

A positron annihilation lifetime study of shock loading in tantalum  

Microsoft Academic Search

Shock loading and quasistatic loading were studied in annealed high purity (99.95%) tantalum in order to characterize the response and identify the physical mechanisms which are responsible. Samples were investigated with positron annihilation lifetime spectroscopy, microhardness measurements, and optical microscopy. The results allow increased damage in the form of dislocation density with increased true strain, but no significant difference in

David Michael Stepp

1998-01-01

14

Design, simulation and performance of a slow positron beam with secondary electron tagging for positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

A positron annihilation lifetime spectrometer using a magnetically guided continuous positron beam and the signal from secondary electrons (SE) emitted from the sample is presented. The positron and secondary electrons trajectories as well as the physics of SE were simulated using GEANT4 program. A special attention was paid to the consequences of positron backscattering, in particular on the shape of the lifetime spectrum. A very good agreement was obtained between simulation and measurements concerning the time resolution (~300–400 ps FWHM) for the studied range of incident positron energies. Due to the complex shape of the resolution function, the present design of the spectrometer is not suited to study of short lifetimes, but can be used for depth profiling porosimetry of materials with Ps formation with the an excellent peak to background ratio of ~105.

Marinov, H.; Djourelov, N.; Nédélec, P.; Petrov, L.

2013-11-01

15

Positron lifetimes in solids from first principles calculations  

SciTech Connect

We present a first principles method for calculating positron lifetimes in solids, based on self-consistent calculations using the Linear Muffin-Tin Orbital method. Local density approximations are used for both electron-electron and electron-positron interactions. Results are presented for a variety of elemental metals and vacancies to demonstrate the reliability of this approach. Theoretical calculations of positron lifetimes can be used to interpret experimental data. As an examples of this, we interpret our experimental lifetime data for the oxide superconductor Ba{sub 1-x}K{sub x}BiO{sub 3} using calculations based on this method. 12 refs., 3 figs.

Sterne, P.A.; O'Brien, J.C.; Howell, R.H. (Lawrence Livermore National Lab., CA (United States)); Kaiser, J.H. (Texas Univ., Arlington, TX (United States). Dept. of Physics)

1991-08-07

16

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

17

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

18

Full potential LAPW calculations of positron lifetimes in materials  

NASA Astrophysics Data System (ADS)

We report positron lifetime calculations for a large number of semiconductors and insulators, including materials of interest for radiation detection. These include CdTe, ZnTe, lanthanide trihalides, orthophosphates, ZnO. Trends in lifetimes with structural features are discussed.

Takenaka, Hiroyuki; Singh, David

2007-03-01

19

Defect dependence of positron lifetimes in oxide superconductors  

SciTech Connect

First principles calculations of the positron lifetimes are used to interpret experimental lifetime data for Ba{sub 1-x}K{sub x}BiO{sub 3}. The observed lifetimes are found to be very sensitive to the presence of defects in the sample. The temperature dependence of the lifetime and the change in lifetime with sample aging are both attributed to defects. The qualitative differences between metal vacancy defects and oxygen vacancy defects in metal oxides are also discussed. 6 refs., 2 figs.

Sterne, P.A.; O'Brien, J.C.; Howell, R.H. (Lawrence Livermore National Lab., CA (USA)); Kaiser, J.H. (Texas Univ., Arlington, TX (USA). Dept. of Physics)

1990-11-01

20

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

21

Measurement of the tau lepton lifetime  

NASA Astrophysics Data System (ADS)

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 result is ?? = 289.0+/-2.8+/-4.0 fs.

Balest, R.; Behrens, B. H.; Cho, K.; Daoudi, M.; Ford, W. T.; Lohner, M.; Park, H.; Rankin, P.; Roy, J.; Smith, J. G.; Alexander, J. P.; Bebek, C.; Berger, B. E.; Berkelman, K.; Bloom, K.; Cassel, D. G.; Cho, H. A.; Coffman, D. M.; Crowcroft, D. S.; Dickson, M.; Drell, P. S.; Dumas, D. J.; Ehrlich, R.; Elia, R.; Gaidarev, P.; Galik, R. S.; Gittelman, B.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Jones, C. D.; Jones, S. L.; Kandaswamy, J.; Katayama, N.; Kim, P. C.; Kreinick, D. L.; T., Lee; Y., Liu; Ludwig, G. S.; Masui, J.; Mevissen, J.; Mistry, N. B.; Ng, C. R.; Nordberg, E.; Patterson, J. R.; Peterson, D.; Riley, D.; Soffer, A.; Ward, C.; Avery, P.; Prescott, C.; S., Yang; Yelton, J.; Brandenburg, G.; Briere, R. A.; T., Liu; Saulnier, M.; Wilson, R.; Yamamoto, H.; Browder, T. E.; F., Li; Rodriguez, J. L.; Bergfeld, T.; Eisenstein, B. I.; Ernst, J.; Gladding, G. E.; Gollin, G. D.; Karliner, I.; Palmer, M.; Selen, M.; Thaler, J. J.; Edwards, K. W.; McLean, K. W.; Ogg, M.; Bellerive, A.; Britton, D. I.; Janicek, R.; Macfarlane, B. D.; Patel, P. M.; Spaan, B.; Sadoff, A. J.; Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Copty, N.; Davis, R.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, N.; Anderson, S.; Kubota, Y.; Lattery, M.; O'Neill, J. J.; Patton, S.; Poling, R.; Riehle, T.; Smith, A.; Savinov, V.; Alam, M. S.; Athar, S. B.; Kim, I. J.; Ling, Z.; Mahmood, A. H.; Severini, H.; Sun, C. R.; Timm, S.; Wappler, F.; Duboscq, J. E.; Fulton, R.; Fujino, D.; Gan, K. K.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; Undrus, A.; White, C.; Wanke, R.; Wolf, A.; Zoeller, M. M.; Nemati, B.; Richichi, S. J.; Ross, W. R.; Skubic, P.; Wood, M.; Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J. W.; Miller, D. H.; Shibata, E. I.; Shipsey, I. P. J.; Yurko, M.; Gibbons, L.; Johnson, S. D.; Kwon, Y.; Roberts, S.; Thorndike, E. H.; Jessop, C. P.; Lingel, K.; Marsiske, H.; Perl, M. L.; Schaffner, S. F.; Wang, R.; Coan, T. E.; Fadeyev, V.; Korolkov, I.; Maravin, Y.; Narsky, I.; Shelkov, V.; Stroynowski, R.; Staeck, J.; Volobouev, I.; Ye, J.; Artuso, M.; Efimov, A.; Gao, M.; Goldberg, M.; Greene, R.; He, D.; Kopp, S.; Moneti, G. C.; Mountain, R.; Mukhin, Y.; Skwarnicki, T.; Stone, S.; X., Xing; Bartelt, J.; Csorna, S. E.; Jain, V.; Marka, S.; Freyberger, A.; Gibaut, D.; Kinoshita, K.; Lai, I. C.; Pomianowski, P.; Schrenk, S.; Bonvicini, G.; Cinabro, D.; Barish, B.; Chadha, M.; S., Chan; Eigen, G.; Miller, J. S.; O'Grady, C.; Schmidtler, M.; Urheim, J.; Weinstein, A. J.; Würthwein, F.; Asner, D. M.; Athanas, M.; Bliss, D. W.; Brower, W. S.; Masek, G.; Paar, H. P.; Gronberg, J.; Korte, C. M.; Lange, D. J.; Kutschke, R.; Menary, S.; Morrison, R. J.; Nakanishi, S.; Nelson, H. N.; Nelson, T. K.; Qiao, C.; Richman, J. D.; Roberts, D.; Ryd, A.; Tajima, H.; Witherell, M. S.

1996-02-01

22

The application of artificial neural networks to the inversion of the positron lifetime spectrum  

NASA Astrophysics Data System (ADS)

A new method of processing positron annihilation lifetime spectra is proposed. It is based on an artificial neural network (ANN)-back propagation network (BPN). By using data from simulated positron lifetime spectra which are generated by a simulation program and tested by other analysis programs, the BPN can be trained to extract lifetime and intensity from a positron annihilation lifetime spectrum as an input. In principle, the method has the potential to unfold an unknown number of lifetimes and their intensities from a measured spectrum. So far, only a proof-of-principle type preliminary investigation was made by unfolding three or four discrete lifetimes. The present study aims to design the network. Besides, the performance of this method requires both the accurate design of the BPN structure and a long training time. In addition, the performance of the method in practical applications is dependent on the quality of the simulation model. However, the chances of satisfying the above criteria appear to be high. When appropriately developed, a trained network could be a very efficient alternative to the existing methods, with a very short identification time. We have used the artificial neural network codes to analyze data such as the positron lifetime spectra for single crystal materials and monocrystalline silicon. Some meaningful results are obtained.

An, Ran; Zhang, Jie; Kong, Wei; Ye, Bang-Jiao

2012-11-01

23

Measurement of the ? lifetime  

Microsoft Academic Search

The t lifetime has been measured with the OPAL detector at LEP, from analyses using the impact parameters in decays to single charged tracks, and the decay lengths from t decays to three charged tracks. The 1991 sample of approximately 12300 t-pair events, of which 70% contain silicon microvertex detector information, has been combined with a re-analysis of the 5100

P. D. Acton; G. Alexander; J. Allison; P. P. Allport; K. J. Anderson; S. Arcelli; A. Astbury; D. Axen; G. Azuelos; G. A. Bahan; J. T. M. Baines; A. H. Ball; J. Banks; R. J. Barlow; S. Barnett; J. R. Batley; G. Beaudoin; A. Beck; J. Becker; T. Behnke; K. W. Bell; G. Bella; P. Bentkowski; P. Berlich; S. Bethke; O. Biebel; U. Binder; I. J. Bloodworth; P. Bock; B. Boden; H. M. Bosch; H. Breuker; P. Brieght-Thomas; R. M. Brown; A. Buijs; H. J. Burckhart; C. Burgard; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; D. G. Charlton; S. L. Chu; P. E. L. Clarke; I. Cohen; J. C. Clayton; W. J. Collins; J. E. Conboy; M. Cooper; M. Coupland; M. Cuffiani; S. Dado; G. M. Dallavalle; S. De Jong; L. A. del Pozo; H. Deng; A. Dieckmann; M. Dittmar; M. S. Dixit; E. do Couto e Silva; J. E. Duboscq; E. Duchovni; G. Duckeck; I. P. Duerdoth; D. J. P. Dumas; P. A. Elcombe; P. G. Estabrooks; E. Etzion; H. G. Evans; F. Fabbri; M. Fierro; M. Fincke-Keeler; H. M. Fischer; D. G. Fong; M. Foucher; A. Gaidot; O. Ganel; J. W. Gary; J. Gascon; R. F. McGowan; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; G. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; J. D. Gillies; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; F. C. Grant; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. F. Harrison; J. Hart; P. M. Hattersley; M. Hauschild; C. M. Hawkes; E. Heflin; R. J. Hemingway; R. D. Heuer; J. C. Hill; S. J. Hillier; T. Hilse; D. A. Hinshaw; J. D. Hobbs; P. R. Hobson; D. Hochman; R. J. Homer; A. K. Honma; R. E. Hughes-Jones; R. Humbert; P. Igo-Kemenes; H. Ihssen; D. C. Imrie; A. C. Janissen; A. Jawahery; P. W. Jeffreys; H. Jeremie; M. Jimack; M. Jobes; R. W. L. Jones; P. Jovanovic; C. Jui; D. Karlen; K. Kawagoe; T. Kawamoto; R. K. Keeler; R. G. Kellogg; B. W. Kennedy; S. Kluth; T. Kobayashi; D. S. Koetke; T. P. Kokott; S. Komamiya; L. Köpke; J. F. Kral; R. Kowalewski; J. von Krogh; J. Kroll; M. Kuwano; P. Kyberd; G. D. Lafferty; R. Lahmann; F. Lamarche; J. G. Layter; P. Leblanc; A. M. Lee; M. H. Lehto; D. Lellouch; C. Leroy; J. Letts; S. Levegrün; L. Levinson; S. L. Lloyd; F. K. Loebinger; J. M. Lorah; B. Lorazo; M. J. Losty; X. C. Lou; J. Ludwig; M. Mannelli; S. Marcellini; G. Maringer; C. Markus; A. J. Martin; J. P. Martin; T. Mashimo; P. Mättig; U. Maur; J. McKenna; T. J. McMahon; J. R. McNutt; F. Meijers; D. Menszner; F. S. Merritt; H. Mes; A. Michelini; R. P. Middleton; G. Mikenberg; J. Mildenberger; D. J. Miller; R. Mir; W. Mohr; C. Moisan; A. Montanari; T. Mori; M. Morii; T. Mouthuy; B. Nellen; H. H. Nguyen; M. Nozaki; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; C. J. Oram; M. J. Oreglia; S. Orito; J. P. Pansart; B. Panzer-Steindel; P. Paschievici; G. N. Patrick; N. Paz-Jaoshvili; P. Pfister; J. E. Pilcher; J. Pinfold; D. Pitman; D. E. Plane; P. Poffenberger; B. Poli; A. Pouladdej; T. W. Pritchard; H. Przysiezniak; G. Quast; M. W. Redmond; D. L. Rees; G. E. Richards; D. Robinson; A. Rollnik; J. M. Roney; E. Ros; S. Rossberg; A. M. Rossi; M. Rosvick; P. Routenburg; K. Runge; O. Runolfsson; D. R. Rust; M. Sasaki; C. Sbarra; A. D. Schaile; O. Schaile; W. Schappert; P. Scharff-Hansen; P. Schenk; B. Schmitt; H. von der Schmitt; S. Schreiber; C. Schwick; J. Schwiening; W. G. Scott; M. Settles; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; R. Shypit; A. Simon; P. Singh; G. P. Siroli; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; R. Sobie; R. W. Springer; M. Sproston; K. Stephens; J. Steuerer; R. Ströhmer; D. Strom; T. Takeshita; P. Taras; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; N. J. Thackray; M. A. Thomson; E. Torrente-Lujan; G. Transtromer; N. J. Tresilian; T. Tsukamoto; M. F. Turner; G. Tysarczyk-Niemeyer; D. Van den plas; R. Van Kooten; G. J. Van Dalen; G. Vasseur; C. J. Virtue; A. Wagner; D. L. Wagner; C. Wahl; J. P. Walker; C. P. Ward; D. R. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; M. Weber; P. Weber; P. S. Wells; N. Wermes; M. A. Whalley; G. W. Wilson; J. A. Wilson; V.-H. Winterer; T. Wlodek; S. Wotton; T. R. Wyatt; R. Yaari; A. Yeaman; G. Yekutieli; M. Yurko; W. Zeuner; G. T. Zorn

1993-01-01

24

Analysis of positron lifetime spectra via a fast Prony algorithm  

NASA Astrophysics Data System (ADS)

A new fast method is used to analyze positron annihilation lifetime spectra. The regularization procedure to solve the inverse problem of finding parameters of useful signals present in the data is formulated. A new approach to determine the number of components in a spectrum is proposed. Results on simulated spectra demonstrate the high resolution capability of the method.

Kul'Ment'ev, A. I.

2004-03-01

25

Positron annihilation lifetime in mesoporous silica MCM-41 at different vacuum levels  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectra of MCM-41 and zeolite Y were measured at different vacuum levels. When the experiments were carried out in air, a very long lifetime component (?4 = 35-45 ns, I4 = 15-20%) was observed for MCM-41, while the longest lifetime for zeolite Y was only 2-4 ns with an intensity of 15-25%. However, when the experiments were carried out in vacuum, the very long lifetime components could be observed for both samples, although with different intensities, ~30% for MCM-41 and ~10% for zeolite Y. For MCM-41 in air, the longest lifetime (?4) is ~42 ns, corresponding to the ortho-positronium (o-Ps) annihilation lifetime in MCM-41 cavities. This value is slightly longer but very close to the value of 39 ns, which was estimated by using a bouncing quantum particle model. These peculiar positron annihilation characteristics were explained by air quenching mechanism of o-Ps annihilation in MCM-41. It was suggested that because of the existence of the very long lifetime component even in air, positron lifetime spectroscopy could be a very useful tool for nondestructive measurement of the cavity size of mesoporous solids such as MCM-41.

He, Y. J.; Zhang, H. Y.; Chen, Y. B.; Wang, H. Y.; Horiuchi, T.

2001-03-01

26

Materials characterization of free volume and void properties by two-dimensional positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy (PALS) has been widely used to determine the free volume and void properties in polymeric materials. Recently, a two dimensional positron annihilation lifetime spectroscopy (2DPALS) system has been developed for membrane applications. The system measures the coincident signals between the lifetime and the energy which could separate the 2? and 3? annihilations and improve the accuracy in the determination of the free volume and void properties. When 2D-PALS is used in coupling with a variable mono-energy slow positron beam, it could be applied to a variety of material characterization. Results of free volumes and voids properties in a multi-layer polymer membrane characterized using 2D-PALS are presented.

Chen, Hongmin; Van Horn, J. David; Jean, Y. C.; Hung, Wei-Song; Lee, Kueir-Rarn

2013-04-01

27

Positron lifetime studies of 100MeV oxygen irradiated Pb-doped Bi2223 superconductors  

Microsoft Academic Search

Positron lifetime studies have been carried out for unirradiated and 100-MeV oxygen ion irradiated Pb-doped Bi-2223 superconductors. The analysis of positron lifetime spectra revealed three lifetime components: a short lifetime, ?1=153–196ps; an intermediate lifetime, ?2=269–339ps; and a long lifetime, ?3=616–812ps. A decrease in all the lifetime components, ?1, ?2 and ?3 with an increase of the relative intensities of I2

T. Banerjee; R. N. Viswanath; D. Kanjilal; R. Kumar; S. Ramasamy

2000-01-01

28

Positron lifetime and Doppler broadening techniques applied to irradiation-damaged silver  

SciTech Connect

Positron lifetime and Doppler broadening measurements have been used to study defect production resulting from room temperature irradiation of pure silver by D-T fusion neutrons or energetic protons. Use of the positron annihilation analysis has established that the surviving defects from both irradiations have the same dose dependence and that defect concentration can be quantitatively measured and compared to damage models. The relative merit of the lifetime and Doppler broadening measurements in arriving at these conclusions is discussed in this report along with some practical aspects of the measurements. In the proton damaged samples the trapping rate approaches saturation, a circumstance which could be misinterpreted if a less extensive data set containing only Doppler broadening data were available. Some remarks about the analysis of positron data and general conclusions about the defect structure are given. 3 figures.

Howell, R.H.

1981-07-27

29

In-situ positron lifetime spectroscopy of radiation damage by simultaneous irradiation of slow-positron and ion beams  

NASA Astrophysics Data System (ADS)

An in-situ positron analysis system has been developed for positron annihilation lifetime spectroscopy during ion beam irradiation. An electron linear accelerator was used to produce a slow positron beam for this system. Positron lifetime spectroscopy of SiO2/Si and annealed pure Fe samples was successfully demonstrated during simultaneous irradiation with a 150 keV Ar+ beam. The lifetime spectra changed with increasing ion dose, indicating a decrease in ortho-positronium intensity (SiO2) and the decrease in positron diffusion length (Fe).

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

2013-06-01

30

Positron lifetime studies of decomposition in 2024 (Al-Cu-Mg) and 7010 (Al-Zn-Cu-Mg) alloys  

Microsoft Academic Search

In the current paper, the decomposition behavior of the engineering alloys 2024 (Al-Cu-Mg) and 7010 (Al-Zn-Cu-Mg) is studied using positron lifetime measurements. Positrons probe open volume defects such as vacancies and dislocations. However, they may also be used to investigate coherent zones and incoherent precipitates. In order to understand the rather complicated precipitation sequences and the response of positrons to

G. Dlubek; P. Lademann; H. Krause; S. Krause; R. Unger

1998-01-01

31

Positron lifetime studies of defect structures in Ba sub 1-x K sub x BiO sub 3  

SciTech Connect

Temperature-dependent positron lifetime experiments have been performed from room temperature to cryogenic temperatures on Ba{sub 1-x}K{sub x}BiO{sub 3}, for x = 0.4 and 0.5. From the temperature dependence of the positron lifetime in the normal state, we observe a clear signature of competition between separate defect populations to trap the positron. Theoretical calculations of lifetimes of free or trapped positrons have been performed on Ba{sub 1-x}K{sub x}BiO{sub 3}, to help identify these defects. Lifetime measurements separated by long times have been performed and evidence of aging effects in the sample defect populations is seen in these materials. 5 refs., 3 figs.

O'Brien, J.C.; Howell, R.H.; Radousky, H.B.; Sterne, P.A. (Lawrence Livermore National Lab., CA (USA)); Hinks, D.G. (Argonne National Lab., IL (USA)); Folkerts, T.J.; Shelton, R.N. (California Univ., Davis, CA (USA))

1990-12-20

32

Positron lifetime studies of decomposition in 2024 (Al-Cu-Mg) and 7010 (Al-Zn-Cu-Mg) alloys  

SciTech Connect

In the current paper, the decomposition behavior of the engineering alloys 2024 (Al-Cu-Mg) and 7010 (Al-Zn-Cu-Mg) is studied using positron lifetime measurements. Positrons probe open volume defects such as vacancies and dislocations. However, they may also be used to investigate coherent zones and incoherent precipitates. In order to understand the rather complicated precipitation sequences and the response of positrons to different type of precipitates occurring in 2024 and 7010 alloys, binary and ternary laboratory alloys were also investigated under the same experimental conditions as the engineering alloys. The interpretations of the results are based on experiences of the group from extensive positron studies of laboratory alloys such as Al-Zn, Al-Zn-Mg, Al-Cu, and further Al alloys (see also the review (4)). Their collected results are shown as lifetimes and curve-shape parameters S of the electron-positron momentum distribution curves characteristic for different precipitates in Al alloys.

Dlubek, G. [ITA Inst. fuer Innovative Technologien GmbH, Halle (Germany)]|[Martin-Luther-Univ. Halle-Wittenberg, Halle (Germany). Fachbereich Physik; Lademann, P.; Krause, H.; Krause, S.; Unger, R. [Martin-Luther-Univ. Halle-Wittenberg, Halle (Germany). Fachbereich Physik

1998-09-04

33

Diffusion of permanent liquid dye molecules in human hair investigated by positron lifetime spectroscopy  

Microsoft Academic Search

The diffusion behavior of a commercial permanent liquid hair dye in human hair has been investigated using positron annihilation lifetime spectroscopy (PALS) and gravimetric sorption method. The positron technique makes it possible to non-invasively characterize the angstrom sized free volume holes in hair, which are supposed to be express pathways for diffusion of small molecules. The o-Ps lifetime parameters ?3

M. N. Chandrashekara; C. Ranganathaiah

2009-01-01

34

Gallium Vacancy in GaSb Studied by Positron Lifetime Spectroscopy and p Photoluminescence.  

National Technical Information Service (NTIS)

Positron lifetime technique and photoluminescence (PL) were employed to study the vacancy type defects in p-type Zn-doped and undoped GaSb samples. In the positron lifetime study, Ga vacancy related defect was identified in these materials and it was foun...

C. C. Ling C. D. Beling M. K. Lui S. Fung W. K. Mui

2002-01-01

35

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

36

Applicability of the MCPNX particle transport code for determination of the source correction effect in positron lifetime measurements on thin polymer films  

SciTech Connect

The method presented herein uses the MCNPX Monte Carlo particle transport code to track individual positrons and other particles through geometry that accounts for the detectors, backing foils, samples and sources with their actual sizes, positions and material characteristics. Polymer material, polydimethylsiloxane (PDMS), with different thickness of films served as samples. The excellent agreement between the experimental results and the MCNPX simulation of source correction effects for varied positron sources and different film thicknesses validates the applicability of the MCNPX code.

J.M. Urban-Klaehn

2007-09-01

37

Positron Annilation Lifetime and Glass Transition Temperatures in CO2 Sorption Polystyrene  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy was used to measure the free-volume size and distributions as a function of temperature in polystyrene with and without 400 psi CO2 sorption. The transition temperatures in the polystyrene with CO2 sorption obtained from ortho-positronium lifetimes were found to depend on the thermal cycles and a meta-stable state showing a negative thermal expansion coefficient was observed between 53°C and 82°C during the first heating up experiment. The observed Tg in polystyrene with, and without CO2 sorption after annealing from ortho-positronium lifetimes were found to be 86°C and 91°C, which are 5°C higher, and 10°C lower than from the differential scanning calorimetry data, respectively. The observed free-volume variations are discussed in terms of hole expansion, creation, free-volume relaxation, plasticization, and hole filling in amorphous polymers.

Jean, Y. C.; Chen, H.; Lee, L. J.; Yang, J.

2008-05-01

38

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

39

Positron Annihilation Energy and Lifetime Spectroscopy Studies for Radiation Defects in Stainless Steel  

SciTech Connect

High Energy proton (up to 800 MeV) and spallation neutron irradiated samples of stainless steel 316 L and Mod 9 CrlMo were studied using positron annihilation energy and lifetime spectroscopy. Irradiation damage caused to 316 L were up to 10 displacements per atom (dpa) and those for 9 CrlMo were up to about 2.5 dpa. Studies of T-parameter, which is calculated as the ratio of the number of counts in the wings of the Doppler-broadened 511 keV peak to the number of counts in the center of the peak, showed that it dropped sharply from 0 to 3.5 dpa, and continued dropping up to 10 dpa in 316 L. In 9 CrlMo, similarly, T-parameter dropped sharply from 0 dpa to 1 dpa, but from 1 dpa to 2.5 dpa it remained constant, indicating that the ''effective'' density of defects, as indicated by T-parameter saturated with the irradiation damage above 1 dpa in 9 CrlMo. We saw no apparent change in the positron lifetime for radiation damages above 3.5 dpa in 316 L. However, for steel 9 CrlMo the positron lifetime in defects increased with irradiation damage from 1.02 dpa to 2.46 dpa. This implies that the electron density at the annihilation sites, defects in this case, decreased. These results led us in both cases to investigate lower radiation damaged samples. We measured energy and lifetime spectra in 316 L and 9 CrlMo samples that were irradiated under the similar conditions as the above samples, but with radiation damage less than 0.1 dpa. These results fill in some of the gap between 0 and 1 dpa and suggest that most of the change in T-parameter occurs at irradiation damages below 0.054 dpa.

Tchelidze, L. [Department of Physics, Idaho State University, 785 S. 8th Ave., Campus Box 8106, Pocatello, Idaho 83209 (United States); Wells, D. P. [Department of Physics, Idaho State University, 785 S. 8th Ave., Campus Box 8106, Pocatello, Idaho 83209 (United States); Idaho Accelerator Center, 1500 Alvin Ricken Drive, Pocatello, Idaho 83201 (United States); Maloy, S. A. [Los Alamos National Lab, P.O. Box 1663, Los Alamos, NM 87545 (United States)

2009-03-10

40

Investigation of Microstructural Changes in Polyetherether-Ketone Films at Cryogenic Temperatures by Positron Lifetime Spectroscopy.  

National Technical Information Service (NTIS)

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 ...

A. Eftekhari D. R. Sprinkle J. J. Singh T. L. St.Clair

1991-01-01

41

Measurement of the tau lifetime  

SciTech Connect

We have used a high-resolution drift chamber in the Mark II detector at the SLAC storage ring PEP to measure the lifetime of tau leptons produced in e/sup +/e/sup -/ annihilations at 29 GeV. Based on the flight-path distribution of 807 three-prong tau decays, the lifetime is found to be (2.88 +- 0.16 +- 0.17) x 10/sup -13/ sec, in agreement with expectations for e-..mu..-tau universality.

Amidei, D.; Trilling, G.H.; Abrams, G.S.; Baden, A.R.; Boyer, J.; Butler, F.; Gidal, G.; Gold, M.K.; Goldhaber, G.; Golding, L.; and others

1988-04-01

42

Positron annihilation measurements of Dy-doped YBCO superconductors  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime and Doppler broadening energy spectra have been measured in Dy-doped high-temperature YBCO superconductors as a function of temperature between 40 and 295 K. The defect-related lifetime component ?2 was approximately constant from room temperature to above Tc at about 90 K and then showed a step-like decrease. These results indicated that the electronic structure changed below Tc. It was also found that a transition in the positron Doppler line-shape parameter S occurred at the superconducting transition temperature. These results show that the average electron momentum at the annihilation sites increases as temperature is lowered across the superconducting transition range.

Jung, K.; Byrne, J. G.; de Andrade, M. C.; Maple, M. B.

1996-02-01

43

Measurement of Charm Meson Lifetimes  

SciTech Connect

We report measurements of the D{sup 0} , D{sup +} , and D{sup +}{sub s} meson lifetimes using 3.7 fb{sup {minus}1} of e{sup +}e{sup {minus}} annihilation data collected near the {Upsilon}(4S) resonance with the CLEO detector. The measured lifetimes of the D{sup 0} , D{sup +} , and D{sup +}{sub s} mesons are 408.5{plus_minus}4.1{sup +3.5}{sub {minus}3.4} fs , 1033.6{plus_minus}22.1{sup +9.9}{sub {minus}12.7} fs , and 486.3{plus_minus}15.0{sup +4.9}{sub {minus}5.1} fs . The precisions of these lifetimes are comparable to those of the best previous measurements, and the systematic errors are very different. In a single experiment we find that the ratio of the D{sup +}{sub s} and D{sup 0} lifetimes is 1.19{plus_minus}0.04 . {copyright} {ital 1999} {ital The American Physical Society}

Bonvicini, G.; Cinabro, D.; Greene, R.; Perera, L.P.; Zhou, G.J. [Wayne State University, Detroit, Michigan 48202 (United States); Chan, S.; Eigen, G.; Lipeles, E.; Schmidtler, M.; Shapiro, A.; Sun, W.M.; Urheim, J.; Weinstein, A.J.; Wuerthwein, F. [California Institute of Technology, Pasadena, California 91125 (United States); Jaffe, D.E.; Masek, G.; Paar, H.P.; Potter, E.M.; Prell, S.; Sharma, V. [University of California, San Diego, La Jolla, California 92093 (United States); Asner, D.M.; Eppich, A.; Gronberg, J.; Hill, T.S.; Korte, C.M.; Lange, D.J.; Morrison, R.J.; Nelson, H.N.; Nelson, T.K.; Roberts, D.; Tajima, H. [University of California, Santa Barbara, California 93106 (United States); Behrens, B.H.; Ford, W.T.; Gritsan, A.; Krieg, H.; Roy, J.; Smith, J.G. [University of Colorado, Boulder, Colorado 80309-0390 (United States); Alexander, J.P.; Baker, R.; Bebek, C.; Berger, B.E.; Berkelman, K.; Boisvert, V.; Cassel, D.G.; Crowcroft, D.S.; Dickson, M.; von Dombrowski, S.; Drell, P.S.; Dumas, D.J.; Ecklund, K.M.; Ehrlich, R.; Foland, A.D.; Gaidarev, P.; Gibbons, L.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Henderson, S.; Hopman, P.I.; Katayama, N.; Kreinick, D.L.; Lee, T.; Liu, Y.; Meyer, T.O.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Ogg, M.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Thayer, J.G.; Thies, P.G.; Valant-Spaight, B.; Warburton, A.; Ward, C. [Cornell University, Ithaca, New York 14853 (United States); Athanas, M.; Avery, P.; Jones, C.D.; Lohner, M.; Prescott, C.; Rubiera, A.I.; Yelton, J.; Zheng, J. [University of Florida, Gainesville, Florida 32611 (United States); Brandenburg, G.; Briere, R.A.; Ershov, A.; Gao, Y.S.; Kim, D.Y.; Wilson, R. [Harvard University, Cambridge, Massachusetts 02138 (United States); Browder, T.E.; Li, Y.; Rodriguez, J.L.; Yamamoto, H. [University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D; and others

1999-06-01

44

Positron lifetime study of poly(dimethylsiloxane) based polymer-nanoparticle composites  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy was employed to study the changes in the size of the local free volume elements (holes) of poly(dimethylsiloxane) (PDMS) based nanocomposites incorporating two different types of nanoparticles, meta-carborane (m-CB) and iso-octyl polyhedral oligomeric silsesquioxane (POSS). Materials were prepared with various loading levels of each nanoparticle and the temperature dependence of the o-Ps lifetime, and thus the free volume, and its distribution were measured from 100–300 K. It was observed that m-CB reduces the size of the local free volume elements while POSS has the opposite effect, in each case the change is only seen in the rubbery state below the so-called "knee temperature" (Tk ~ 210 K).

Hughes, D. J.; Roussenova, M. V.; Beavis, P.; Swain, A. C.; Alam, M. A.

2013-06-01

45

Measurement of the ?+c lifetime  

NASA Astrophysics Data System (ADS)

We observe 97 decays of the charmed baryon, the ?+c, into a pK-?+ final state in a Fermilab photoproduction experiment. The mass is measured to be 2286.2+/-1.7+/-0.7 MeV/c2. The positions of the production and decay vertices are reconstructed with the use of silicon microstrip vertex detector. From these measurements, we determine the lifetime of the ?c to be (0.22+/-0.03 +/-0.02)×10-12 s.

Anjos, J. C.; Appel, J. A.; Bean, A.; Bracker, S. B.; Browder, T. E.; Cremaldi, L. M.; Elliott, J. R.; Escobar, C. O.; Estabrooks, P.; Gibney, M. C.; Hartner, G. F.; Karchin, P. E.; Kumar, B. R.; Losty, M. J.; Luste, G. J.; Mantsch, P. M.; Martin, J. F.; McHugh, S.; Menary, S. R.; Morrison, R. J.; Nash, T.; Nauenberg, U.; Ong, P.; Pinfold, J.; Punkar, G.; Purohit, M. V.; Raab, J. R.; Santoro, A. F.; Sidhu, J. S.; Sliwa, K.; Sokoloff, M. D.; Souza, M. H.; Spalding, W. J.; Streetman, M. E.; Stundia, A. B.; Witherell, M. S.

1988-04-01

46

Measurement of the (27)P lifetime  

NASA Astrophysics Data System (ADS)

The lifetime of 27P has been measured using the Recoil Mass Spectrometer (RMS) at the Nuclear Structure Research Laboratory (NSRL) at the University of Rochester. 27P was produced by bombarding a BeO target with a 24Mg beam at a lab energy of 118 MeV. A focal-plane detector system, consisting of a parallel-grid avalanche counter (PGAC) backed by an ionization counter (IC) and a silicon detector, was used to provide particle identification. A sodium iodide detector array was used to detect the 511 keV positron annihilation radiation produced by the decay of 27P. The result obtained for the half-life of 27P is 0.32 -0.15+0.22 s.

Freeman, Charles George

47

Lifetime Measurements in ^71Se  

NASA Astrophysics Data System (ADS)

In the light selenium isotopes, ^71Se appears to be a transitional nucleus, showing signs of competing single particle and collective structures, but its level structure is not well known. The present work measured lifetimes in ^71Se in order to quantify the degree of collectivity as a function of spin as the configuration of the unpaired neutron changes. ^71Se nuclei were produced at high spin by a ^54Fe(^23Na,?pn) fusion reaction at 80 MeV conducted at Florida State University. Fifteen lifetimes were measured from the resulting gamma-ray coincidence data using the Doppler-shift attenuation method. Experimental transition quadrupole moments Qt were inferred from the lifetimes and found to be in rough agreement with the predictions of cranked Woods-Saxon calculations. Comparisons with neighboring odd-mass nuclei confirmed that ^71Se exhibits moderate collectivity. Based on coincidence relations and systematic arguments, the level scheme was enhanced and extended to higher spin. A band that was previously assigned positive parity was reassigned as the ``missing'' signature partner of an existing negative-parity band.

Howe, A. R.; Kaye, R. A.; Baker, N. R.; Arora, S. R.; Bruckman, J. K.; Tabor, S. L.; Hinners, T. A.; Hoffman, C. R.; Lee, S.; D"{O}Ring, J.

2009-10-01

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

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

PubMed

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. PMID:23742543

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

2013-05-01

50

Lifetime measurement in 124Te  

NASA Astrophysics Data System (ADS)

Lifetimes of nuclear levels in 124Te have been measured by the /?-ray induced Doppler broadening (GRID) technique using the GAMS4 crystal spectrometer at the Institut Laue Langevin, Grenoble. The new experimental data allow the determination of absolute transition rates. The results show that the structure of 124Te is best described by a configuration mixing calculation in the framework of the IBM-2. Precise /?-ray measurements confirm a 2+-3+ level doublet at 2039 keV with a spacing of 129 eV.

Doll, C.; Lehmann, H.; Börner, H. G.; von Egidy, T.

2000-06-01

51

Lifetime measurements in 135Pr  

NASA Astrophysics Data System (ADS)

Lifetimes of low-lying levels in the ?I=2 band built on the ?h11/2 state in the Z-odd nucleus 135Pr were measured with the Doppler-shift recoil-distance technique. Reduced transition probabilities B(E2) were extracted in order to calculate the deformation parameters. These values were compared to theoretical results of the total Routhian surface (TRS) calculations. While the quadrupole moments obtained for the ?h11/2 excited levels below the first backbend in 135Pr are very similar to those of the 134Ce core, TRS results predict a quadrupole moment of about 50% larger for the core.

Botelho, S.; Seale, W. A.; Emediato, L. G. R.; Oliveira, J. R. B.; Rao, M. N.; Ribas, R. V.; Medina, N. H.; Cybulska, E. W.; Rizzutto, M. A.; Espinoza-Quiñones, F. R.; García-Bermúdez, G.; Somacal, H.; Cardona, M. A.

1998-12-01

52

Glucose and water diffusion kinetics study in a fluorosilicone acrylate contact lens material by positron lifetime spectroscopy  

Microsoft Academic Search

A comparative study of water and glucose sorption in a rigid gas-permeable contact lens polymer, Fluoroperm 92, has been carried out using positron annihilation lifetime spectroscopy, gravimetric analysis and refractive index measurements. The water sorption in FP92 is non-Fickian, whereas for glucose sorption it changes to Fickian. Glucose molecules reduce the interaction of water molecules with the polymer, resulting in

M. V. Deepa Urs; C. Ranganathaiah

2007-01-01

53

Measurement of Recombination Lifetimes in Superconductors  

Microsoft Academic Search

It is shown that the experimentally measured quasiparticle recombination lifetime in a superconductor is not the same as the previously calculated theoretical lifetime. A simple expression relating the two is derived.

Allen Rothwarf; B. N. Taylor

1967-01-01

54

Positron annihilation lifetime study of pure and Na(acac) treated polyvinylalcohol  

Microsoft Academic Search

Positron annihilation lifetime studies of pxre and treated polyvinyl alcohol (PYA) reflect the effect of concentration as well ae temperature on free volume. Therefore, variations of the lifetime of the o-PS longlived component r3 and the probability of its formation I3 have been studied and correlated with changes in the electrical conductivity CY as well as with X-ray diffraction data.

A. M. A. EL-SAYED; E. E. ABDEL-HADY; M. MOHSEN; A. SAWABY

1993-01-01

55

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

56

Dynamics of polycarbonate far below the glass transition temperature: A positron annihilation lifetime study  

Microsoft Academic Search

In this study, we have extended the knowledge of the dynamics of polycarbonate (PC) far below Tg by means of positron annihilation lifetime spectroscopy (PALS), which is able to detect the isothermal relaxation of the free volume after rejuvenation above Tg. The free volume relaxation patterns at different temperatures below Tg were modeled according to a phenomenological model presented by

D. Cangialosi; M. Wübbenhorst; H. Schut; A. van Veen; S. J. Picken

2004-01-01

57

Positron annihilation lifetime spectroscopy based on secondary electron emission from carbon foil  

NASA Astrophysics Data System (ADS)

Using the emission of secondary electron (SE) from a thin carbon foil in transmission geometry guided by a strong radial electric field in the region between the foil and the sample under investigation, a new variable energy positron annihilation lifetime spectroscopy (PALS) system is being implemented. To this end, the SE emission from a carbon foil of 30nm thick has been investigated in transmission geometry. Considerable emission of SE from the foil with peak energy of about 5eV is observed. We have found that both the energy loss and dispersion of the positrons after transmission through the carbon foil are small enough for the proposed positron lifetime-depth profiling PALS system to be realised. These experimental results and the timing simulations of Cai et. al. [1] indicate that the proposed variable PALS based on secondary electrons generated by carbon foil have a high time resolution.

Ng, C. K.; Yang, B.; Fung, S.

2013-06-01

58

Development of an Electron-Positron Source for Positron Annihilation Lifetime Spectroscopy.  

National Technical Information Service (NTIS)

The extremely strong fields produced by focusing powerful laser pulses into minute volumes of material enable relativistic effects to be used to generate radiation, to accelerate particles, and to produce electrons and positrons from vacuum. From applicat...

A. Modovanakis B. Hou I. Sokolov J. Easter J. Nees

2009-01-01

59

Investigation on the porosity of zeolite NU-88 by means of positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Seven well characterized zeolites were investigated by positron annihilation lifetime spectroscopy. The lifetime spectra were analysed in four discrete components. The third one was associated with ortho-positronium annihilation in the channels, framed in terms of infinite cylinders. Differences between the radii determined from the positron annihilation technique and X-ray diffraction data were found and explained in terms of the physical structure of the channel. An analogous study on a high-silica NU-88 zeolite gave a value of 0.33 nm for the corresponding radius, in agreement with Ar and N2 adsorption data as well as with the catalytic behaviour of this zeolite in several acid catalyzed reactions. The longest lifetime component in NU-88 reveals the existence of mesopores, with average radius of about 1.8 nm, which could explain the importance of hydrogen transfer reactions in this zeolite.

Consolati, G.; Mariani, M.; Millini, R.; Quasso, F.

2009-08-01

60

Positron line-shape parameters and lifetimes for semiconductors: Systematics and temperature effects  

NASA Astrophysics Data System (ADS)

Positron Doppler broadening and lifetime experiments have been performed on C (diamond), SiC, Si, Ge, GaN, GaP, GaAs, GaSb, InP, InAs, and InSb. It was found that the Doppler-broadening parameter arising from valence electrons depends linearly on the free-electron gas rs value when calculated from the valence-electron density. Positron lifetimes due to valence electrons are found to be proportional to r3>s. Finer details, which result from the bonded character of the valence electrons, are revealed by slight anisotropies of the S parameter. Temperature dependencies in the 100-600-K temperature range studied by means of Doppler broadening show a complex behavior which in part may be defect influenced.

Dannefaer, S.; Puff, W.; Kerr, D.

1997-01-01

61

Evolution of porosity in a Portland cement paste studied through positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy experiments were carried out in an ordinary Portland cement paste characterized by a water-to-cement ratio /w/c=0.8, in order to monitor the porosity of the paste. It was found that ortho-positronium intensity is a suitable quantity to this purpose, being sensitive to the amount of water contained in the pores. The experimental data show good agreement with the porosity calculated according to the Powers' model.

Consolati, G.; Quasso, F.

2003-10-01

62

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

63

Development of a pico-second life-time spectrometer for positron annihilation studies.  

National Technical Information Service (NTIS)

Positron annihilation technique is a sensitive probe to investigate various physico-chemical phenomena due to the ability to provide information about the electron momentum and density in any medium. While measurements on the Doppler broadening and angula...

P. K. Pujari T. Datta B. S. Tomar S. K. Das

1992-01-01

64

Lifetime measurement in ^170Yb  

NASA Astrophysics Data System (ADS)

The nature of the low lying K^?=0^+ excitations in deformed nuclei have recently been subject of intense discussion. In this context we present results from a Coulomb excitation experiment on ^170Yb using a 70MeV ^16O beam on a gold backed, 1.5 mg/cm^2 thick ^170Yb target. The beam was delivered by the ESTU tandem accelerator of WNSL at Yale University. Gamma rays were detected by the YRAST Ball array in coincidence with back-scattered ^16O particles, which were detected in an array of 8 solar cells. Lineshapes were observed for several transitions from collective states in ^170Yb and the lifetimes for those states were extracted using a standard DSAM analysis. The results will be presented together with a short introduction to the solar cell array at Yale (SCARY) that was used to make angular selection of the excited ^170Yb nuclei. This work is supported by the US-DOE under grant numbers DE-FG02-91ER-40609 and DE-FG02-88ER-40417.

Wang, Z.; Krücken, R.; Beausang, C. W.; Casten, R. F.; Cooper, J. R.; Cederkäll, J.; Caprio, M.; Novak, J. R.; Zamfir, N. V.; Barton, C.

1999-10-01

65

Measurement of the lambda(+)(c) lifetime.  

PubMed

The Lambda+c lifetime is measured using 9.0 fb(-1) of e+e- annihilation data collected on or just below the Upsilon(4S) resonance with the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the Lambda+c lifetime is measured to be 179.6+/-6.9(stat)+/-4.4(syst) fs. The precision of this colliding beam measurement is comparable to other measurements, which are based on fixed-target experiments, with different systematic uncertainties. PMID:11289897

Mahmood, A H; Csorna, S E; Danko, I; McLean, K W; Márka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Schrenk, S; Bonvicini, G; Cinabro, D; McGee, S; Perera, L P; Zhou, G J; Lipeles, E; Pappas, S P; Schmidtler, M; Shapiro, A; Sun, W M; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Hill, T S; Morrison, R J; Nelson, H N; Briere, R A; Chen, G P; Behrens, B H; Ford, W T; Gritsan, A; Roy, J; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, D G; Dickson, M; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kandaswamy, J; Kreinick, D L; Lohner, M; Magerkurth, A; Meyer, T O; Mistry, N B; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Urner, D; Valant-Spaight, B; Warburton, A; Avery, P; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J; Brandenburg, G; Ershov, A; Gao, Y S; Kim, D Y; Wilson, R; Browder, T E; Li, Y; Rodriguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J; Ammar, R; Bean, A; Besson, D; Davis, R; Kwak, N; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R; Riehle, T; Smith, A; Stepaniak, C J; Urheim, J; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Eckhart, E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pedlar, T K; Schwarthoff, H; Thayer, J B; von Toerne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P; Undrus, A; Chen, S; Fast, J; Hinson, J W; Lee, J; Miller, D H; Shibata, E I; Shipsey, I P; Pavlunin, V; Cronin-Hennessy, D; Lyon, A L; Thorndike, E H; Jessop, C P; Marsiske, H; Perl, M L; Savinov, V; Zhou, X; Coan, T E; Fadeyev, V; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Boulahouache, C; Bukin, K; Dambasuren, E; Karamov, S; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Kopp, S

2001-03-12

66

Comparative studies of positron annihilation lifetime and coincident Doppler broadening spectra for a binary Cd-based quasicrystal and 1/1-approximant crystal  

SciTech Connect

We performed the positron annihilation lifetime and coincident Doppler broadening measurements for binary icosahedral quasicrystal Cd{sub 5.7}Ca and its 1/1-cubic Cd{sub 6}Ca and Cd{sub 6}Yb approximants. Since the obtained positron lifetimes are quite similar to one another, it is likely that the same type of structural vacancies exists in quasicrystal Cd{sub 5.7}Ca and 1/1-cubic Cd{sub 6}Ca and Cd{sub 6}Yb approximants. The vacancy-type defects are concluded to be surrounded mostly by Cd atoms in both quasicrystal Cd{sub 5.7}Ca and its 1/1-cubic approximant Cd{sub 6}Ca from the high-momentum Doppler broadening spectra. In addition, we studied the temperature dependence of the positron annihilation lifetime in the low temperature region from 10 to 300 K for 1/1-cubic approximant Cd{sub 6}Ca and Cd{sub 6}Yb crystals. As a whole, in both 1/1-cubic Cd{sub 6}Ca and Cd{sub 6}Yb approximants the positron lifetime {tau}{sub 1} gradually increases with increasing temperature due to isotropic thermal expansion. However, the positron lifetime {tau}{sub 1} does not change at the order-disorder transition temperature, namely, 100 and 110 K for 1/1-cubic Cd{sub 6}Ca and Cd{sub 6}Yb approximants, respectively. These results suggest that the size of the structural vacancies and local electron density do not change with the ordering.

Takagiwa, Y.; Kanazawa, I.; Sato, K.; Murakami, H.; Kobayashi, Y.; Tamura, R.; Takeuchi, S. [Department of Physics, Tokyo Gakugei University, 4-1-1 Koganei, Tokyo 184-0051 (Japan); Department of Environmental Science, Tokyo Gakugei University, 4-1-1 Koganei, Tokyo 184-0051 (Japan); National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Department of Materials Science and Technology, Tokyo University of Science, Noda, Chiba 278-8501 (Japan)

2006-03-01

67

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

68

Alkali-doped heavy metal fluoride glasses studied by positron annihilation lifetime spectroscopy  

Microsoft Academic Search

Heavy metal fluoride glasses of varying alkali metal fluoride have been studied by positron annihilation lifetime spectroscopy. The alkali series 53ZrF4 · (40 - x)BaF2 · 4LaF3 · 3AlF3 · xLiF and 53ZrF4 · (40 - x)BaF2 · 4LaF3 · 3AlF3 · xCsF are compared with the mixed alkali series 53ZrF4 · 20BaF2 · 4LaF3 · 4LaF3 · 3AlF3 ·

A. J. Hill; P. J. Newman; J. Javorniczky; D. R. MacFarlane

1995-01-01

69

A simple shape-free model for pore-size estimation with positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy is one of the methods for estimating pore size in insulating materials. We present a shape-free model to be used conveniently for such analysis. A basic model in classical picture is modified by introducing a parameter corresponding to an effective size of the positronium (Ps). This parameter is adjusted so that its Ps-lifetime to pore-size relation merges smoothly with that of the well-established Tao-Eldrup model (with modification involving the intrinsic Ps annihilation rate) applicable to very small pores. The combined model, i.e., modified Tao-Eldrup model for smaller pores and the modified classical model for larger pores, agrees surprisingly well with the quantum-mechanics based extended Tao-Eldrup model, which deals with Ps trapped in and thermally equilibrium with a rectangular pore.

Wada, Ken; Hyodo, Toshio

2013-06-01

70

Updated measurement of the ? lepton lifetime  

NASA Astrophysics Data System (ADS)

A new measurement of the mean lifetime of the ? lepton is presented. Three different analysis methods are applied to a sample of 90 000 ? pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement and those previously published by ALEPH is ??=290.1+/-1.5+/-1.1 fs.

ALEPH Collaboration; Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, Ll. M.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Becker, U.; Bazarko, A. O.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rizzo, G.; Rolandi, L.; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Zachariadou, K.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, E.; Thomson, F.; Turnbull, R. M.; Buchmüller, O.; Dhamotharan, S.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Spagnolo, P.; Stacey, A. M.; Williams, M. D.; Ghete, V. M.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W. L.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Carr, J.; Coyle, P.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; St. Denis, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Schune, M.-H.; Simion, S.; Tournefier, E.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.

1997-11-01

71

Updated measurement of the tau lepton lifetime  

Microsoft Academic Search

A new measurement of the mean lifetime of the tau lepton is presented. Three different analysis methods are applied to a sample of 90 000 tau pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement and those previously published by ALEPH is tautau=290.1+\\/-1.5+\\/-1.1 fs.

R. Barate; D. Buskulic; D. Decamp; P. Ghez; C. Goy; J.-P. Lees; A. Lucotte; M.-N. Minard; J.-Y. Nief; B. Pietrzyk; M Chmeissani; M. Chmeissani; P. Comas; J. M. Crespo; M. Delfino; E. Fernandez; M. Fernandez-Bosman; Ll. Garrido; A. Juste; M. Martinez; G. Merino; R. Miquel; Ll. M. Mir; C. Padilla; I. C. Park; A. Pascual; J. A. Perlas; I. Riu; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; G. Gelao; G. Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Nuzzo; A. Ranieri; G. Raso; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; A. Tricomi; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; D. Abbaneo; R. Alemany; U. Becker; A. O. Bazarko; P. Bright-Thomas; M. Cattaneo; F. Cerutti; G. Dissertori; H. Drevermann; R. W. Forty; M. Frank; R. Hagelberg; J. B. Hansen; J. Harvey; P. Janot; B. Jost; E. Kneringer; J. Knobloch; I. Lehraus; P. Mato; A. Minten; L. Moneta; A. Pacheco; J.-F. Pusztaszeri; F. Ranjard; G. Rizzo; L. Rolandi; D. Rousseau; D. Schlatter; M. Schmitt; O. Schneider; W. Tejessy; I. R. Tomalin; H. Wachsmuth; A. Wagner; Z. Ajaltouni; A. Barrès; C. Boyer; A. Falvard; C. Ferdi; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J.-C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; P. Rosnet; J.-M. Rossignol; T. Fearnley; J. D. Hansen; P. H. Hansen; B. S. Nilsson; B. Rensch; A. Wäänänen; G. Daskalakis; A. Kyriakis; C. Markou; E. Simopoulou; I. Siotis; A. Vayaki; 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; K. Zachariadou; 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; J. M. Scarr; K. Smith; P. Teixeira-Dias; A. S. Thompson; E. Thomson; F. Thomson; R. M. Turnbull; O. Buchmüller; S. Dhamotharan; C. Geweniger; G. Graefe; P. Hanke; G. Hansper; V. Hepp; E. E. Kluge; A. Putzer; J. Sommer; K. Tittel; S. Werner; M. Wunsch; R. Beuselinck; D. M. Binnie; W. Cameron; P. J. Dornan; M. Girone; S. Goodsir; E. B. Martin; A. Moutoussi; J. Nash; J. K. Sedgbeer; P. Spagnolo; A. M. Stacey; M. D. Williams; V. M. Ghete; P. Girtler; D. Kuhn; G. Rudolph; A. P. Betteridge; C. K. Bowdery; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; R. W. L. Jones; T. Sloan; M. I. Williams; A. Galla; I. Giehl; A. M. Greene; C. Hoffmann; K. Jakobs; K. Kleinknecht; G. Quast; B. Renk; E. Rohne; H.-G. Sander; P. van Gemmeren; C. Zeitnitz; J. J. Aubert; C. Benchouk; A. Bonissent; G. Bujosa; J. Carr; P. Coyle; C. Diaconu; F. Etienne; N. Konstantinidis; O. Leroy; F. Motsch; P. Payre; M. Talby; A. Sadouki; M. Thulasidas; K. Trabelsi; M Antonelli; F. Ragusa; R. Berlich; W. Blum; V. Büscher; H. Dietl; G. Ganis; C. Gotzhein; 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; H. Stenzel; W. Wiedenmann; G. Wolf; J. Boucrot; O. Callot; S. Chen; Y. Choi; A. Cordier; M. Davier; L. Duflot; J.-F. Grivaz; Ph. Heusse; A. Höcker; A. Jacholkowska; M. Jacquet; D. W. Kim; F. Le Diberder; J. Lefrançois; A.-M. Lutz; I. Nikolic; M.-H. Schune; S. Simion; E. Tournefier; J.-J. Veillet; I. Videau; D. Zerwas; P. Azzurri; G Batignani; 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; F. Palla; G. Sanguinetti; A. Sciabà; J. Steinberger; R. Tenchini; G. Tonelli; C. Vannini; A. Venturi; P. G. Verdini; G. A. Blair; L. M. Bryant; 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. R. Norton; J. C. Thompson; A. E. Wright; B. Bloch-Devaux; P. Colas; S. Emery; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; P. Perez; J F Renardy; A. Roussarie; 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; M. S. Kelly; M. Lehto; W. M. Newton; J. Reeve; L. F. Thompson; A. Böhrer; S. Brandt; G. Cowan; C. Grupen; G. Lutters; P. Saraiva; L. Smolik; F. Stephan; M. Apollonio; L. Bosisio; R. della Marina; G. Giannini; B. Gobbo; G. Musolino; J. Putz; J. Rothberg; S. Wasserbaech; S. R. Armstrong; E. Charles; P. Elmer; D. P. S. Ferguson; S. González; T. C. Greening; O. J. Hayes; H. Hu; S. Jin; P. A. McNamara III; J. M. Nachtman; J. Nielsen

1997-01-01

72

Updated measurement of the ? lepton lifetime  

Microsoft Academic Search

A new measurement of the mean lifetime of the ? lepton is presented. Three different analysis methods are applied to a sample of 90 000 ? pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement and those previously published by ALEPH is ?? = 290.1 ± 1.5 ± 1.1 fs.

R. Barate; D. Buskulic; D. Decamp; P. Ghez; C. Goy; J.-P. Lees; A. Lucotte; M.-N. Minard; J.-Y. Nief; B. Pietrzyk; M. P. Casado; M. Chmeissani; P. Comas; J. M. Crespo; M. Delfino; E. Fernandez; M. Fernandez-Bosman; Ll. Garrido; A. Juste; M. Martinez; G. Merino; R. Miquel; Ll. M. Mir; C. Padilla; I. C. Park; A. Pascual; J. A. Perlas; I. Riu; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; G. Gelao; G. Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Nuzzo; A. Ranieri; G. Raso; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; A. Tricomi; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; D. Abbaneo; R. Alemany; U. Becker; A. O. Bazarko; P. Bright-Thomas; M. Cattaneo; F. Cerutti; G. Dissertori; H. Drevermann; R. W. Forty; M. Frank; R. Hagelberg; J. B. Hansen; J. Harvey; P. Janot; B. Jost; E. Kneringer; J. Knobloch; I. Lehraus; P. Mato; A. Minten; L. Moneta; A. Pacheco; J.-F. Pusztaszeri; F. Ranjard; G. Rizzo; L. Rolandi; D. Rousseau; D. Schlatter; M. Schmitt; O. Schneider; W. Tejessy; I. R. Tomalin; H. Wachsmuth; A. Wagner; Z. Ajaltouni; A. Barrès; C. Boyer; A. Falvard; C. Ferdi; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J. C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; P. Rosnet; J.-M. Rossignol; T. Fearnley; J. D. Hansen; P. H. Hansen; B. S. Nilsson; B. Rensch; A. Wäänänen; G. Daskalakis; A. Kyriakis; C. Markou; E. Simopoulou; I. Siotis; A. Vayaki; 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; K. Zachariadou; 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; J. M. Scarr; K. Smith; P. Teixeira-Dias; A. S. Thompson; E. Thomson; F. Thomson; R. M. Turnbull; O. Buchmüller; S. Dhamotharan; C. Geweniger; G. Graefe; P. Hanke; G. Hansper; V. Hepp; E. E. Kluge; A. Putzer; J. Sommer; K. Tittel; S. Werner; M. Wunsch; R. Beuselinck; D. M. Binnie; W. Cameron; P. J. Dornan; M. Girone; S. Goodsir; E. B. Martin; A. Moutoussi; J. Nash; J. K. Sedgbeer; P. Spagnolo; A. M. Stacey; M. D. Williams; V. M. Ghete; P. Girtler; D. Kuhn; G. Rudolph; A. P. Betteridge; C. K. Bowdery; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; R. W. L. Jones; T. Sloan; M. I. Williams; A. Galla; I. Giehl; A. M. Greene; C. Hoffmann; K. Jakobs; K. Kleinknecht; G. Quast; B. Renk; E. Rohne; H.-G. Sander; P. van Gemmeren; C. Zeitnitz; J. J. Aubert; C. Benchouk; A. Bonissent; G. Bujosa; J. Carr; P. Coyle; C. Diaconu; F. Etienne; N. Konstantinidis; O. Leroy; F. Motsch; P. Payre; M. Talby; A. Sadouki; M. Thulasidas; K. Trabelsi; M. Aleppo; M. Antonelli; F. Ragusa; R. Berlich; W. Blum; V. Büscher; H. Dietl; G. Ganis; C. Gotzhein; 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; H. Stenzel; W. Wiedenmann; G. Wolf; J. Boucrot; O. Callot; S. Chen; Y. Choi; A. Cordier; M. Davier; L. Duflot; J.-F. Grivaz; Ph. Heusse; A. Höcker; A. Jacholkowska; M. Jacquet; D. W. Kim; F. Le Diberder; J. Lefrançois; A.-M. Lutz; I. Nikolic; M.-H. Schune; S. Simion; E. Tournefier; J.-J. Veillet; I. Videau; D. Zerwas; 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; F. Palla; G. Sanguinetti; A. Sciabà; J. Steinberger; R. Tenchini; G. Tonelli; C. Vannini; A. Venturi; P. G. Verdini; G. A. Blair; L. M. Bryant; 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. R. Norton; J. C. Thompson; A. E. Wright; B. Bloch-Devaux; P. Colas; S. Emery; W. Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; 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; M. S. Kelly; M. Lehto; W. M. Newton; J. Reeve; L. F. Thompson; A. Böhrer; S. Brandt; G. Cowan; C. Grupen; G. Lutters; P. Saraiva; L. Smolik; F. Stephan; M. Apollonio; L. Bosisio; R. Della Marina; G. Giannini; B. Gobbo; G. Musolino; J. Putz; J. Rothberg; S. Wasserbaech; S. R. Armstrong; E. Charles; P. Elmer; D. P. S. Ferguson; S. González; T. C. Greening; O. J. Hayes; H. Hu; S. Jin

1997-01-01

73

Positron annihilation measurements of Pr-containing superconductor compounds  

SciTech Connect

Positron annihilation lifetime and Doppler broadening energy spectra have been measured in Pr-containing YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} as a function of temperature between 18 and 295 K. The defect-related positron lifetime component {tau}{sub 2} was independent of temperature for the PrBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} compound and was very close to the value {tau}{sub 1} associated with bulk or defect-free material. These results indicate that the structure of this compound is nearly free of defects which trap positrons and that there is no electronic structure change during cooling. There was a slight temperature dependence below {ital T}{sub {ital c}} for the Y{sub 0.5}Pr{sub 0.5}Ba{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} compound. It was also found that a change in the positron Doppler line-shape parameter {ital S} occurred at the superconducting transition temperature for 0.5 Pr-containing compound but not for the 1.0 Pr-containing compound. These results show that the average electron momentum at the annihilation sites increases as temperature is lowered across the superconducting transition range for the 0.5 Pr-containing compound but not for the PrBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} compound. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Jung, K.; Byrne, J.G. [Department of Metallurgical Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); de Andrade, M.C.; Maple, M.B. [Department of Physics and Institute for Pure and Applied Physical Sciences, University of California at San Diego, La Jolla, California 92093-0360 (United States)

1995-11-01

74

Measurements of the b baryon lifetime  

NASA Astrophysics Data System (ADS)

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 ?l- combinations containing a b baryon sample of 290 decays, the measured b baryon lifetime is ?b-baryon = 1.05+0.12-0.11 (stat) +/- 0.09 (syst) ps. The lifetime of the ?0b baryon from a maximum likelihood fit to the proper time distribution of 58 ?+cl- candidates containing a ?0b sample of 44 decays, is ??0b = 1.02+0.23-0.18 (stat) +/- 0.06 (syst) ps.

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

1995-02-01

75

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

76

A measurement of the KS lifetime  

NASA Astrophysics Data System (ADS)

A measurement of the KS lifetime is presented using data recorded by the NA48 experiment at the CERN-SPS during 1998 and 1999. The KS lifetime is derived from the ratio of decay time distributions in simultaneous, collinear KS and KL beams, giving a result which is approximately independent of the detector acceptance and with reduced systematic errors. The result obtained is ?S=(0.89598+/-0.00048+/-0.00051)×10-10 s, where the first error is statistical and the second systematic.

NA48 Collaboration; Lai, A.; Marras, D.; Batley, J. R.; Bevan, A.; Dosanjh, R. S.; Gershon, T. J.; Hay, B.; Kalmus, G. E.; Lazzeroni, C.; Munday, D. J.; Needham, M. D.; Olaiya, E.; Parker, M. A.; White, T. O.; Wotton, S. A.; Barr, G.; Bocquet, G.; Ceccucci, A.; Cuhadar-Dönszelmann, T.; Cundy, D.; D'Agostini, G.; Doble, N.; Falaleev, V.; Funk, W.; Gatignon, L.; Gonidec, A.; Gorini, B.; Govi, G.; Grafström, P.; Kubischta, W.; Lacourt, A.; Lenti, M.; Luitz, S.; Matheys, J. P.; Mikulec, I.; Norton, A.; Palestini, S.; Panzer-Steindel, B.; Schinzel, D.; Tatishvili, G.; Taureg, H.; Velasco, M.; Vossnack, O.; Wahl, H.; Cheshkov, C.; Gaponenko, A.; Hristov, P.; Kekelidze, V.; Madigojine, D.; Molokanova, N.; Potrebenikov, Yu.; Tkatchev, A.; Zinchenko, A.; Knowles, I.; Martin, V.; Parsons, H.; Sacco, R.; Walker, A.; Contalbrigo, M.; Dalpiaz, P.; Duclos, J.; Frabetti, P. L.; Gianoli, A.; Martini, M.; Petrucci, F.; Savrié, M.; Scarpa, M.; Bizzeti, A.; Calvetti, M.; Collazuol, G.; Graziani, G.; Iacopini, E.; Martelli, F.; Veltri, M.; Becker, H. G.; Blümer, H.; Coward, D.; Eppard, M.; Fox, H.; Hirstius, A.; Holtz, K.; Kalter, A.; Kleinknecht, K.; Koch, U.; Köpke, L.; Lopes da Silva, P.; Marouelli, P.; Pellmann, I.; Peters, A.; Schmidt, S. A.; Schönharting, V.; Schué, Y.; Wanke, R.; Winhart, A.; Wittgen, M.; Chollet, J. C.; Crépé, S.; Fayard, L.; Iconomidou-Fayard, L.; Ocariz, J.; Unal, G.; Wingerter-Seez, I.; Anzivino, G.; Cenci, P.; Imbergamo, E.; Lubrano, P.; Mestvirishvili, A.; Nappi, A.; Pepe, M.; Piccini, M.; Bertanza, L.; Bigi, A.; Calafiura, P.; Carosi, R.; Casali, R.; Cerri, C.; Cirilli, M.; Costantini, F.; Fantechi, R.; Giudici, S.; Mannelli, I.; Pierazzini, G.; Sozzi, M.; Cheze, J. B.; Cogan, J.; De Beer, M.; Debu, P.; Derue, F.; Formica, A.; Granier de Cassagnac, R.; Mazzucato, E.; Peyaud, B.; Turlay, R.; Vallage, B.; Augustin, I.; Bender, M.; Holder, M.; Maier, A.; Ziolkowski, M.; Arcidiacono, R.; Biino, C.; Cartiglia, N.; Guida, R.; Marchetto, F.; Menichetti, E.; Pastrone, N.; Nassalski, J.; Rondio, E.; Szleper, M.; Wislicki, W.; Wronka, S.; Dibon, H.; Fischer, G.; Jeitler, M.; Markytan, M.; Neuhofer, G.; Pernicka, M.; Taurok, A.; Widhalm, L.

2002-06-01

77

Lifetime measurements in {sup 178}Hf  

SciTech Connect

Lifetimes of levels from K{sup {pi}} = 2{sup +}, K{sup {pi}} = 4{sup +} and several K{sup {pi}} = 0{sup +} bands have been measured in the {sup 178}Hf nucleus using the GRID technique. Lifetimes of the 2{sup +} and 3{sup +} levels were measured within the K{sup {pi}} = 2{sup +} {gamma} band. A lower limit was established for the lifetime of the 4{sup +} level of the K{sup {pi}} = 4{sup +} band. The resulting upper limits for the absolute B(E2) values exclude collective transitions from the K{sup {pi}} = 4{sup +} to the ground state band but not to the K{sup {pi}} = 2{sup +} {gamma} band. Level lifetimes were also measured for several states within three separate K{sup {pi}} = 0{sup +} bands. Evidence is presented for a previously unobserved case of two excited K{sup {pi}} = 0{sup +} bands being connected via collective E2 transitions.

Haan, R.C. de; Aprahamian, A.; Boerner, H.G.; Doll, C.; Jentschel, M.; Bruce, A.M.; Lesher, S.R.

2000-02-01

78

High Precision Measurement of the Neon-19 Lifetime  

NASA Astrophysics Data System (ADS)

The lifetime of 19Ne is an important parameter in precision tests of the Standard Model. Improvement in the uncertainty of experimental observables of this and other T = ½ mirror isotopes would allow for an extraction of Vud at a similar precision to that obtained by superallowed 0+ ? 0 + Fermi decays. We report on a new high precision measurement of the lifetime of 19Ne, performed at the Kernfysich Versneller Instituut (KVI) in Groningen, the Netherlands. A 10.5 MeVA 19F beam was used to produce 19Ne using inverse reaction kinematics in a H2 gas target. Contaminant productions were eliminated using the TRImuP magnetic isotope separator. The 19Ne beam was implanted into a thick aluminum tape, which was translated to a shielded detection region by a custom tape drive system. Collinear annihilation radiation from the emitted decay positrons were detected by two high purity germanium (HPGe) detectors. Event pulse waveforms were digitized and stored using a CAEN V1724 Digitizer. Systematic studies were performed to characterize rate-dependent data acquisition effects, diffusion, backgrounds, and contamination from the separator. We have obtained the result for the lifetime of tau = 24.9344 +/- 0.0073(stat) +/- 0.0083( sys) seconds.

Broussard, Leah Jacklyn

79

Measurement of the BS0 lifetime  

Microsoft Academic Search

The lifetime of the Bs0 meson has been measured with the OPAL detector at LEP. A sample of Bs0 (B¯s0) decays has been obtained using Ds- l+ (and charge conjugate, where l denotes a lepton) combinations, where the Ds- was reconstructed in either the phipi- of K*0K- channel. The decay lengths of Ds- l+ combinations were measured using vertex reconstruction.

P. D. Acton; R. Akers; Gideon Alexander; J. Allison; K. J. Anderson; S. Arcelli; Alan Astbury; D. Axen; Georges Azuelos; J. T. M. Baines; A. H. Ball; J. Banks; R. J. Barlow; S. Barnett; R. Bartoldus; J Richard Batley; G. Beaudoin; A. Beck; G. A. Beck; J. Becker; C. Beeston; T. Behnke; K. W. Bell; G. Bella; P. Bentkowski; P. Berlich; Siegfried Bethke; O. Biebel; Ian J Bloodworth; P. Bock; B. Boden; H. M. Bosch; M. Boutemeur; H. Breuker; P G Bright-Thomas; R. M. Brown; A. Buijs; Helfried J Burckhart; C. Burgard; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; D. G. Charlton; S. L. Chu; P. E. L. Clarke; J. C. Clayton; I. Cohen; J. E. Conboy; M. Cooper; M. Coupland; M. Cuffiani; S. Dado; G. M. Dallavalle; S. de Jong; L. A. del Pozo; H. Deng; A. Dieckmann; Michael Dittmar; M. S. Dixit; E. Do Couto E Silva; J. E. Duboscq; E. Duchovni; G. Duckeck; I. P. Duerdoth; D. J. P. Dumas; P. A. Elcombe; P. G. Estabrooks; E. Etzion; H. G. Evans; Franco Luigi Fabbri; B. Fabbro; M. Fierro; Margret Fincke-Keeler; H. M. Fischer; D. G. Fong; M. Foucher; A. Gaidot; J. W. Gary; J. Gascon; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; G. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; J. D. Gillies; J. Goldberg; D. M. Gingrich; M. J. Goodrick; W. Gorn; C. Grandi; F. C. Grant; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. F. Harrison; J. Hart; P. M. Hattersley; M. Hauschild; C. M. Hawkes; E. Heflin; Richard J Hemingway; G. Herten; R. D. Heuer; J. C. Hill; S. J. Hillier; T. Hilse; D. A. Hinshaw; J. D. Hobbs; P. R. Hobson; D. Hochman; R James Homer; A. K. Honma; R. E. Hughes-Jones; R. Humbert; P. Igo-Kemenes; H. Ihssen; D. C. Imrie; A. C. Janissen; A. Jawahery; P. W. Jeffreys; H. Jeremie; Martin Paul Jimack; M. Jones; R. W. L. Jones; P. Jovanovic; C. Jui; D. Karlen; K. Kawagoe; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; S. Kluth; T. Kobayashi; D. S. Koetke; T. P. Kokott; S. Komamiya; L. Köpke; J. F. Kral; R. Kowalewski; J. von Krogh; J. Kroll; M. Kuwano; P. Kyberd; G. D. Lafferty; H. Lafoux; R. Lahmann; F. Lamarche; J. G. Layter; P. Leblanc; A. M. Lee; M. H. Lehto; Daniel Lellouch; C. Leroy; J. Letts; S. Levegrün; L. Levinson; S. L. Lloyd; F. K. Loebinger; J. M. Lorah; B. Lorazo; Michael J Losty; X. C. Lou; J. Ludwig; M. Mannelli; S. Marcellini; C. Markus; A. J. Martin; J. P. Martin; T. Mashimo; P. Mättig; U. Maur; J. McKenna; T. J. McMahon; J. R. McNutt; F. Meijers; D. Menszner; F. S. Merritt; H. Mes; A. Michelini; R. P. Middleton; G. Mikenberg; J. Mildenberger; D. J. Miller; R. Mir; W. Mohr; C. Moisan; A. Montanari; T. Mori; M. Morii; U. Müller; B. Nellen; H. H. Nguyen; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; C. J. Oram; M. J. Oreglia; S. Orito; J. P. Pansart; B. Panzer-Steindel; P. Paschievici; G. N. Patrick; N. Paz-Jaoshvili; M. J. Pearce; P. Pfister; J. E. Pilcher; J. Pinfold; D. Pitman; D. E. Plane; P. Poffenberger; B. Poli; A. Pouladdej; T. W. Pritchard; H. Przysiezniak; G. Quast; M. W. Redmond; D. L. Rees; G. E. Richards; S. A. Robins; D. Robinson; A. Rollnik; J. M. Roney; E. Ros; S. Rossberg; A. M. Rossi; M. Rosvick; P. Routenburg; K. Runge; O. Runolfsson; D. R. Rust; M. Sasaki; C. Sbarra; A. D. Schaile; O. Schaile; W. Schappert; P. Scharff-Hansen; B. Schmitt; H. von der Schmitt; M. Schröder; C. Schwick; J. Schwiening; W. G. Scott; M. Settles; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; G. P. Siroli; A. Skillman; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; Randall J Sobie; R. W. Springer; M. Sproston; A. Stahl; C. Stegmann; K. Stephens; J. Steuerer; R. Ströhmer; D. Strom; H. Takeda; T. Takeshita; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; M. A. Thomson; E. Torrente-Lujan; S. Towers; G. Transtromer; N. J. Tresilian; T. Tsukamoto; M. F. Turner; D. van den Plas; R. van Kooten; G. J. Vandalen; G. Vasseur; C. J. Virtue; A. Wagner; D. L. Wagner; C. Wahl; C. P. Ward; D. R. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; M. Weber; P. Weber; P. S. Wells; N. Wermes; M. A. Whalley; B. Wilkens; G. W. Wilson; J. A. Wilson; V.-H. Winterer; T. Wlodek; G. Wolf; S. Wotton; T. R. Wyatt; R. Yaari; A. Yeaman; G. Yekutieli; M. Yurko; W. Zeuner; G. T. Zorn; Roberto Tenchini; G Tonelli; G Triggiani; Andrea Valassi; C Vannini; A Maltezos; P G Verdini; J Marco; A P Betteridge; J C Marin; A Markou; D L Johnson; P V March; L G Mathis; F Matorras; C Matteuzzi; Giorgio Matthiae; M Mazzucato; David R Botterill; R W Clifft; T R Edgecock; S Haywood; M Edwards; P R Norton; M Michelotto; B Bloch-Devaux; L Mirabito; Winfried A Mitaroff; G Mitselmakher; Witold Kozanecki; E Lançon; M C Lemaire; K Mönig; M R Monge; P Morettini; H Müller; J F Renardy; Gerald Myatt; Francesco Luigi Navarria; J P Schuller; J Schwindling; D Si Mohand; V Nikolaenko

1993-01-01

80

Measurement of the tau lepton lifetime  

Microsoft Academic Search

The tau lepton lifetime has been measured using two independent techniques; an impact parameter analysis of the 1-prong decays and a decay length analysis of the 3-prong decays. Approximately 5 000 Z0 decays to tau+tau- have been selected from the data collected with the OPAL detector at LEP during 1990. The results of the two statistically independent measurements are, respectively,

P. D. Acton; Gideon Alexander; J. Allison; P. P. Allport; K. J. Anderson; S. Arcelli; P. Ashton; Alan Astbury; D A Axen; Georges Azuelos; G. A. Bahan; J. T. M. Baines; A. H. Ball; J. Banks; G. J. Barker; R. J. Barlow; J Richard Batley; G. Beaudoin; A. Beck; J. Becker; T. Behnke; K. W. Bell; G. Bella; P. Berlich; Siegfried Bethke; O. Biebel; U. Binder; Ian J Bloodworth; P. Bock; B. Boden; H. M. Bosch; S. Bougerolle; B. B. Brabson; Horst Breuker; R. M. Brown; R. Brun; A. Buijs; Helfried J Burckhart; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; D. G. Charlton; P. E. L. Clarke; I. Cohen; W. J. Collins; J. E. Conboy; M. Cooper; M. Couch; M. Coupland; M. Cuffiani; S. Dado; G. M. Dallavalle; S. de Jong; P. Debu; L. A. del Pozo; M. M. Deninno; A. Dieckmann; Michael Dittmar; M. S. Dixit; E. Duchovni; G. Duckeck; I. P. Duerdoth; D. J. P. Dumas; G. Eckerlin; P. A. Elcombe; P. G. Estabrooks; E. Etzion; Franco Luigi Fabbri; Margret Fincke-Keeler; H. M. Fischer; D. G. Fong; C. Fukunaga; A. Gaidot; O. Ganel; J. W. Gary; J. Gascon; R. F. McGowan; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; G. Giacomelli; V. Gibson; W. R. Gibson; James D Gillies; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; F. C. Grant; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. F. Harrison; J. Hart; P. M. Hattersley; M. Hauschild; C. M. Hawkes; E. Heflin; Richard J Hemingway; R. D. Heuer; J. C. Hill; S. J. Hillier; D. A. Hinshaw; C. Ho; J. D. Hobbs; P. R. Hobson; D. Hochman; B. Holl; R James Homer; A. K. Honma; S. R. Hou; C. P. Howarth; R. E. Hughes-Jones; R. Humbert; P. Igo-Kemenes; H. Ihssen; D. C. Imrie; A. C. Janissen; A. Jawahery; P. W. Jeffreys; H. Jeremie; Martin Paul Jimack; M. Jobes; R. W. L. Jones; P. Jovanovic; D A Karlen; K. Kawagoe; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; C. Kleinwort; D. E. Klem; T. Kobayashi; T. P. Kokott; S. Komamiya; L. Köpke; J. F. Kral; R V Kowalewski; H. Kreutzmann; J. von Krogh; J. Kroll; M. Kuwano; P. Kyberd; G. D. Lafferty; F. Lamarche; W. J. Larson; J. G. Layter; P. Le Du; P. Leblanc; A. M. Lee; M. H. Lehto; Daniel Lellouch; P. Lennert; C. Leroy; J. Letts; S. Levegrün; L. Levinson; S. L. Lloyd; F. K. Loebinger; J. M. Lorah; B. Lorazo; Michael J Losty; X. C. Lou; J. Ludwig; M. Mannelli; S. Marcellini; G. Maringer; A. J. Martin; J. P. Martin; T. Mashimo; P. Mättig; U. Maur; J A McKenna; T. J. McMahon; J. R. McNutt; F. Meijers; D. Menszner; F. S. Merritt; H. Mes; Aldo Michelini; R. P. Middleton; G. Mikenberg; J L Mildenberger; D. J. Miller; R. Mir; W. Mohr; C. Moisan; A. Montanari; T. Mori; M. W. Moss; T. Mouthuy; B. Nellen; H. H. Nguyen; M. Nozaki; S. W. O'Neale; B. P. O'Neill; F. G. Oakham; F. Odorici; M. Ogg; H. O. Ogren; H. Oh; C. J. Oram; M. J. Oreglia; S. Orito; J. P. Pansart; B. Panzer-Steindel; P. Paschievici; G. N. Patrick; S. J. Pawley; P. Pfister; J. E. Pilcher; James L Pinfold; D. Pitman; D. E. Plane; P R Poffenberger; B. Poli; A. Pouladdej; E J Prebys; T. W. Pritchard; H. Przysiezniak; G. Quast; M. W. Redmond; D. L. Rees; K. Riles; S. A. Robins; D. Robinson; A. Rollnik; J. M. Roney; E. Ros; S. Rossberg; A. M. Rossi; M. Rosvick; P. Routenburg; K. Runge; O. Runolfsson; D. R. Rust; S. Sanghera; M. Sasaki; A. D. Schaile; O. Schaile; W. Schappert; P. Scharff-Hansen; P. Schenk; H. von der Schmitt; S. Schreiber; J. Schwiening; W. G. Scott; M. Settles; B. C. Shen; P. Sherwood; R. Shypit; A. Simon; P. Singh; G. P. Siroli; A M Smith; A. M. Smith; T. J. Smith; G. A. Snow; R W Springer; R. W. Springer; M. Sproston; K. Stephens; H. E. Stier; R. Ströhmer; D. Strom; H. Takeda; T. Takeshita; P. Taras; S. Tarem; P. Teixeira-Dias; N. J. Thackray; G. Transtromer; T. Tsukamoto; M. F. Turner; G. Tysarczyk-Niemeyer; D. van den Plas; R. van Kooten; G. J. Vandalen; G. Vasseur; C. J. Virtue; A. Wagner; C P Ward; J. P. Walker; D. R. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; M. Weber; P S Wells; S. Weisz; N. Wermes; M A Whalley; G. W. Wilson; J. A. Wilson; I. Wingerter; V.-H. Winterer; N. C. Wood; S. Wotton; T. R. Wyatt; R. Yaari; Y. Yang; G. Yekutieli; M. Yurko; I. Zacharov; W. Zeuner; G. T. Zorn

1991-01-01

81

Mass and Lifetime Measurements in Storage Rings  

SciTech Connect

Masses of nuclides covering a large area of the chart of nuclides can be measured in storage rings where many ions circulate at the same time. In this paper the recent progress in the analysis of Schottky mass spectrometry data is presented as well as the technical improvements leading to higher accuracy for isochronous mass measurements with a time-of-flight detector. The high sensitivity of the Schottky method down to single ions allows to measure lifetimes of nuclides by observing mother and daughter nucleus simultaneously. In this way we investigated the decay of bare and H-like 140Pr. As we could show the lifetime can be even shortened compared to those of atomic nuclei despite of a lower number of electrons available for internal conversion or electron capture.All these techniques will be implemented with further improvements at the storage rings of the new FAIR facility at GSI in the future.

Weick, H.; Beckert, K.; Beller, P.; Bosch, F.; Dimopoulou, C.; Kozhuharov, C.; Kurcewicz, J.; Mazzocco, M.; Nociforo, C.; Nolden, F.; Steck, M.; Sun, B.; Winkler, M. [Gesellschaft fuer Schwerionenforschung mbH, 64291 Darmstadt (Germany); Brandau, C.; Chen, L.; Geissel, H.; Knoebel, R.; Litvinov, S. A.; Litvinov, Yu. A.; Scheidenberger, C. [Gesellschaft fuer Schwerionenforschung mbH, 64291 Darmstadt (Germany); II. Phys. Institut, Justus-Liebig-Universitaet Giessen, 35392 Giessen (Germany)] (and others)

2007-05-22

82

Structural study of polymer hydrogel contact lenses by means of positron annihilation lifetime spectroscopy and UV-vis-NIR methods.  

PubMed

A study has been conducted in order to determine presence of free volume gaps in the structure of structure of polymer hydrogel contact lenses made in phosphoryl choline technology and of the degree of defect of its structure. The study was made by means of positron annihilation lifetime spectroscopy. As a result of the conducted measurements, curves were obtained, which described numbers of counts of the acts of annihilation in the time function. The conducted studies revealed existence of three components ?(1), ?(2) and ?(3). The ?(3) component is attributed to the pick-off annihilation of o-Ps orthopositronium trapping by free volume gaps and provides information about geometrical parameters of the volumes. At the same time, the UV-vis-NIR spectrometry examination was conducted on the same samples in the spectral range 200-1,000 nm. PMID:23695358

Filipecki, J; Kocela, A; Korzekwa, P; Miedzinski, R; Filipecka, K; Golis, E; Korzekwa, W

2013-05-22

83

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

84

Chemical environment in halogenated styrene polymers studied by using positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Polystyrene samples, incorporated with halogen elements (F, Cl, Br, I) on the para-position of the benzene ring, were studied using positron annihilation lifetime spectroscopy. It was found that the free-volume hole size is significantly affected by the internal Coulombic interaction of the halogen group, and is mainly related to the electronegativity of halogen-carbon bonds. In addition, it is found that the free-volume is secondarily modified by the steric effect of the side groups. The intensity of o-Ps has a linear relationship with the strength of the C-X bond and is strongly affected by the chemical environment in a halogenated styrene polymer system.

Zhang, R.; Wu, Y. C.; Chen, H.; Zhang, J.; Li, Y.; Sandreczki, T. C.; Jean, Y. C.

2003-10-01

85

Measurement of the B0-meson lifetime  

Microsoft Academic Search

We report a measurement of the lifetime of the B0 meson based upon 29-GeV e+e- annihilation data taken with the Mark II detector at the SLAC storage ring PEP. The B0 mesons are tagged by their decays into D*-e+nu and D*-mu+nu, where the D*- is tagged by its decay into pi-D¯ 0. We reconstruct the decay vertices of 15 B0-meson

S. R. Wagner; D. A. Hinshaw; R. A. Ong; A. Snyder; G. Abrams; C. E. Adolphsen; C. Akerlof; J. P. Alexander; M. Alvarez; D. Amidei; A. R. Baden; J. Ballam; B. C. Barish; T. Barklow; B. A. Barnett; J. Bartelt; D. Blockus; G. Bonvicini; A. Boyarski; J. Boyer; B. Brabson; A. Breakstone; J. M. Brom; F. Bulos; P. R. Burchat; D. L. Burke; F. Butler; F. Calvino; R. J. Cence; J. Chapman; D. Cords; D. P. Coupal; H. C. Destaebler; D. E. Dorfan; J. M. Dorfan; P. S. Drell; G. J. Feldman; E. Fernandez; R. C. Field; W. T. Ford; C. Fordham; R. Frey; D. Fujino; K. K. Gan; G. Gidal; L. Gladney; T. Glanzman; M. S. Gold; G. Goldhaber; A. Green; P. Grosse-Wiesmann; J. Haggerty; G. Hanson; R. Harr; F. A. Harris; C. M. Hawkes; K. Hayes; D. Herrup; C. A. Heusch; T. Himel; R. J. Hollebeek; D. Hutchinson; J. Hylen; W. R. Innes; M. Jaffre; J. A. Jaros; I. Juricic; J. A. Kadyk; D. Karlen; J. Kent; S. R. Klein; W. Koska; W. Kozanecki; A. J. Lankford; R. R. Larsen; B. W. Leclaire; M. E. Levi; A. M. Litke; N. S. Lockyer; V. Lüth; J. A. Matthews; D. I. Meyer; B. D. Milliken; K. C. Moffeit; L. Müller; J. Nash; M. E. Nelson; D. Nitz; H. Ogren; K. F. O'shaughnessy; S. I. Parker; C. Peck; M. L. Perl; A. Petersen; M. Petradza; F. C. Porter; P. Rankin; B. Richter; K. Riles; P. C. Rowson; D. R. Rust; H. F. Sadrozinski; T. Schaad; T. L. Schalk; H. Schellman; W. B. Schmidke; A. S. Schwarz; A. Seiden; P. D. Sheldon; J. G. Smith; E. Soderstrom; D. P. Stoker; R. Stroynowski; R. Thun; G. H. Trilling; R. Tschirhart; R. van Kooten; H. Veltman; P. Voruganti; P. Weber; A. J. Weinstein; S. Weisz; S. L. White; E. Wicklund; A. J. Weir; D. R. Wood; D. Y. Wu; J. M. Yelton

1990-01-01

86

Lifetime measurements in {sup 112}Sb  

SciTech Connect

Lifetimes of some high-spin states in the negative parity magnetic dipole band in {sup 112}Sb were determined using the Doppler-shift attenuation method. The deduced M1 transition rates show a small decrease with increasing spin. This decrease is reasonably accounted for within the framework of the tilted axis cranking (TAC) model. There also appears to be a considerable contribution from collective rotation. This is the first indication of such behavior in the A{approx_equal}110 mass region, determined through lifetime measurements. The TAC calculations based on a {pi}g{sub 9/2}{sup -1}x{nu}h{sub 11/2} configuration reproduce the magnetic dipole band.

Deo, A.Y.; Tandel, S.K.; Patel, S.B.; Madhusudhana Rao, P.V.; Muralithar, S.; Singh, R.P.; Kumar, R.; Bhowmik, R.K.; Amita [Department of Physics, University of Mumbai, Vidyanagari, Mumbai 400 098 (India); Department of Nuclear Physics, Andhra University, Visakhapatnam 530 003 (India); Nuclear Science Centre, P.O. Box 10502, New Delhi 110 067 (India); Department of Physics, RBS College, Agra 282 002 (India)

2005-01-01

87

A measurement of the tau lifetime  

NASA Astrophysics Data System (ADS)

The tau lepton lifetime is measured using four different methods with the DELPHI detector. Three measurements using one prong decays are combined, accounting for correlations, resulting in ??=298 +/-7 (stat.)+/-4 (syst.) fs while the decay length distribution of three prong decays gives ??=298+/-13 (stat)+/-(syst.) fs. The combined result is ??=298+/-7 fs. The ratio of the Fermi coupling constant from tau decay relative to that from muon decay is found to be 0.985+/-0.013, compatible with lepton universality.

Abreu, P.; Adam, W.; Adye, T.; Agasi, E.; Aleksan, R.; Alekseev, G. D.; Algeri, A.; Allen, P.; Almehed, S.; Alvsvaag, S. J.; Amaldi, U.; Anassontzis, E. G.; Andreazza, A.; Antilogus, P.; Apel, W.-D.; Apsimon, R. J.; Arnoud, Y.; Å, B.; Augustin, J.-E.; Augustinus, A.; Baillon, P.; Bambade, P.; Barao, F.; Barate, R.; Barbiellini, G.; Bardin, D. Y.; Barker, G. J.; Baroncelli, A.; Barring, O.; Barrio, J. A.; Bartl, W.; Bates, M. J.; Battaglia, M.; Baubillier, M.; Becks, K.-H.; Beeston, C. J.; Begalli, M.; Beilliere, P.; Belokopytov, Yu.; Beltran, P.; Benedic, D.; Benvenuti, A. C.; Berggren, M.; Bertrand, D.; Bianchi, F.; Bilenky, M. S.; Billoir, P.; Bjarne, J.; Bloch, D.; Blyth, S.; Bocci, V.; Bogolubov, P. N.; Bolognese, T.; Bonesini, M.; Bonivento, W.; Booth, P. S. L.; Borisov, G.; Borner, H.; Bosio, C.; Bostjancic, B.; Bosworth, S.; Botner, O.; Bouquet, B.; Bourdarios, C.; Bowcock, T. J. V.; Bozzo, M.; Braibant, S.; Branchini, P.; Brand, K. D.; Brenner, R. A.; Briand, H.; Bricman, C.; Brown, R. C. A.; Brummer, N.; Brunet, J.-M.; Bugge, L.; Buran, T.; Burmeister, H.; Buytaert, J. A. M. A.; Caccia, M.; Calvi, M.; Camacho Rozas, A. J.; Campion, R.; Camporesi, T.; Canale, V.; Cao, F.; Carena, F.; Carroll, L.; Castillo Gimenez, M. V.; Cattai, A.; Cavallo, F. R.; Cerrito, L.; Chabaud, V.; Chan, A.; Charpentier, Ph.; Chaussard, L.; Chauveau, J.; Checchia, P.; Chelkov, G. A.; Chevalier, L.; Chliapnikov, P.; Chorowicz, V.; Chrin, J. T. M.; Clara, M. P.; Collins, P.; Contreras, J. L.; Contri, R.; Cortina, E.; Cosme, G.; Couchot, F.; Crawley, H. B.; Crennell, D.; Crosetti, G.; Crozon, M.; Cuevas Maestro, J.; Czellar, S.; Dahl-Jensen, E.; Dalmagne, B.; Dam, M.; Damgaard, G.; Darbo, G.; Daubie, E.; Daum, A.; Dauncey, P. D.; Davenport, M.; David, P.; Davies, J.; da Silva, W.; Defoix, C.; Delpierre, P.; Demaria, N.; de Angelis, A.; de Boeck, H.; de Boer, W.; de Clercq, C.; de Fez Laso, M. D. M.; de Groot, N.; de La Vaissiere, C.; de Lotto, B.; de Min, A.; Dijkstra, H.; di Ciaccio, L.; Djama, F.; Dolbeau, J.; Donszelmann, M.; Doroba, K.; Dracos, M.; Drees, J.; Dris, M.; Dufour, Y.; Dupont, F.; Eek, L.-O.; Eerola, P. A.-M.; Ehret, R.; Ekelof, T.; Ekspong, G.; Elliot Peisert, A.; Engel, J.-P.; Ershaidat, N.; Fassouliotis, D.; Feindt, M.; Fenyuk, A.; Fernandez Alonso, M.; Ferrer, A.; Filippas, T. A.; Firestone, A.; Foeth, H.; Fokitis, E.; Fontanelli, F.; Forbes, K. A. J.; Fousset, J.-L.; Francon, S.; Franek, B.; Frenkiel, P.; Fries, D. C.; Frodesen, A. G.; Fruhwirth, R.; Fulda-Quenzer, F.; Furnival, K.; Furstenau, H.; Fuster, J.; Gamba, D.; Garcia, C.; Garcia, J.; Gaspar, C.; Gasparini, U.; Gavillet, Ph.; Gazis, E. N.; Gerber, J.-P.; Giacomelli, P.; Gokieli, R.; Golob, B.; Golovatyuk, V. M.; Gomez Y Cadenas, J. J.; Goobar, A.; Gopal, G.; Gorski, M.; Gracco, V.; Grant, A.; Grard, F.; Graziani, E.; Grosdidier, G.; Gross, E.; Grosse-Wiesmann, P.; Grossetete, B.; Gumenyuk, S.; Guy, J.; Haedinger, U.; Hahn, F.; Hahn, M.; Haider, S.; Hajduk, Z.; Hakansson, A.; Hallgren, A.; Hamacher, K.; Hamel de Monchenault, G.; Hao, W.; Harris, F. J.; Hedberg, V.; Henkes, T.; Hernandez, J. J.; Herquet, P.; Herr, H.; Hessing, T. L.; Hietanen, I.; Higgins, C. O.; Higon, E.; Hilke, H. J.; Hodgson, S. D.; Hofmokl, T.; Holmes, R.; Holmgren, S.-O.; Holthuizen, D.; Honore, P. F.; Hooper, J. E.; Houlden, M.; Hrubec, J.; Huet, K.; Hulth, P. O.; Hultqvist, K.; Ioannou, P.; Iversen, P.-S.; Jackson, J. N.; Jalocha, P.; Jarlskog, G.; Jarry, P.; Jean-Marie, B.; Johansson, E. K.; Johnson, D.; Jonker, M.; Jonsson, L.; Juillot, P.; Kalkanis, G.; Kalmus, G.; Kapusta, F.; Karlsson, M.; Karvelas, E.; Katsanevas, S.; Katsoufis, E. C.; Keranen, R.; Kesteman, J.; Khomenko, B. A.; Khovanski, N. N.; King, B.; Kjaer, N. J.; Klein, H.; Klovning, A.; Kluit, P.; Koch-Mehrin, A.; Koehne, J. H.; Koene, B.; Kokkinias, P.; Koratzinos, M.; Korcyl, K.; Korytov, A. V.; Kostioukhine, V.; Kourkoumelis, C.; Kouznetsov, O.; Kramer, P. H.; Krolikowski, J.; Kronkvist, I.; Kruener-Marquis, U.; Kucewicz, W.; Kulka, K.; Kurvinen, K.; Lacasta, C.; Lambropoulos, C.; Lamsa, J. W.; Lanceri, L.; Lapin, V.; Laugier, J.-P.; Lauhakangas, R.; Leder, G.; Ledroit, F.; Leitner, R.; Lemoigne, Y.; Lemonne, J.; Lenzen, G.; Lepeltier, V.; Lesiak, T.; Levy, J. M.; Lieb, E.; Liko, D.; Lindgren, J.; Lindner, R.; Lipniacka, A.; Lippi, I.; Loerstad, B.; Lokajicek, M.; Loken, J. G.; Lopez-Fernandez, A.; Lopez Aguera, M. A.; Los, M.; Loukas, D.; Lozano, J. J.; Lutz, P.; Lyons, L.; Maehlum, G.; Maillard, J.; Maio, A.; Maltezos, A.; Mandl, F.; Marco, J.; Margoni, M.; Marin, J.-C.; Markou, A.; Maron, T.; Marti, S.; Mathis, L.; Matorras, F.; Matteuzzi, C.; Matthiae, G.; Mazzucato, M.; Mc Cubbin, M.; Mc Nay, R.; Mc Nulty, R.; Meola, G.; Meroni, C.; Meyer, W. T.; Michelotto, M.; Mikulec, I.

1993-03-01

88

Positron annihilation lifetime and Doppler broadening study in 50 MeV Li3+ ion irradiated polystyrene films  

NASA Astrophysics Data System (ADS)

Swift heavy ion (SHI) irradiation of polymeric materials results in the change of their free volume properties which have strong correlation with their macroscopic properties. The modification depends on the polymer and ion beam parameters, namely ion energy, fluence and ion species. Polystyrene films were irradiated with Li3+ ions of energy 50 MeV from 15 UD Pelletron accelerators at Inter University Accelerator Centre (IUAC), New Delhi, India to the fluences of 1011, 1012 and 1013 ions/cm2. Nanosized free volume parameters in the polymer have been studied by positron annihilation lifetime spectroscopy (PALS) and Doppler broadening spectroscopy (DBS). From o-Ps lifetime ?3, free volume hole radius, mean free volume of microvoids and fractional free volume are computed and modification in free volume with the fluence is studied. Free volume parameters change slowly with ion fluence with a decrease at the highest fluence of 1013 ions/cm2. The decrease in ?3 and I3 (reflecting the number of free volume holes) may be interpreted on the process of cross-linking. S parameter obtained from DBS measurements showed a minor decrease with increasing fluence.

Asad Ali, S.; Kumar, Rajesh; Nambissan, P. M. G.; Singh, F.; Prasad, Rajendra

2010-06-01

89

Level Lifetime Measurements in ^150Sm  

NASA Astrophysics Data System (ADS)

Shape/phase coexistence and the evolution of structure in the region around ^152Sm have recently been of great interest. Experiments performed at WNSL, Yale University, measured the lifetime of low spin states in a target of ^150Sm with the recoil distance method (RDM) and the Doppler-shift attenuation method (DSAM). The low spin states, both yrast and non-yrast, were populated via Coulomb excitation with a beam of ^16O. The experiments were performed with the NYPD plunger in conjunction with the SPEEDY ?-ray array. The SCARY array of solar cells was used to detect backward scattered projectiles, selecting forward flying Coulomb excited target nuclei. The measured lifetimes yield, for example, B(E2) values for transitions such as the 2^+2 arrow 2^+1 and the 2^+3 arrow 0^+_1. Data from the RDM measurment and the DSAM experiment will be presented. This work was supported by the US DOE under grants DE-FG02-91ER-40609 and DE-FG02-88ER-40417.

Barton, C. J.; Krücken, R.; Beausang, C. W.; Caprio, M. A.; Casten, R. F.; Cooper, J. R.; Hecht, A. A.; Newman, H.; Novak, J. R.; Pietralla, N.; Wolf, A.; Zyromski, K. E.; Zamfir, N. V.; Börner, H. G.

2000-10-01

90

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

91

Electron and positron densities and the temperature dependence of the positron lifetime in a vacancy in aluminum  

Microsoft Academic Search

The results of an augmented-plane-wave calculation of the electron and positron density distributions in a vacancy in Al are reported. The environment of the vacancy was simulated by a super cell with a volume 27 times that of the primative unit cell. These results show that jellium-model calculations overestimate the electron density in a vacancy. The variation of the positron

Raju Gupta; R. W. Siegel

1977-01-01

92

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

93

Lifetime measurements in 129,131Xe  

NASA Astrophysics Data System (ADS)

Lifetimes of positive-parity levels in 129,131Xe have been measured by a new technique based on the recoil-distance method. The reduced E2 and M1 transition probabilities B(E2) and B(M1) deduced from these data have been compared with the predictions of nuclear models, in particular the interacting boson-fermion model (IBFM). Some dynamical symmetries of the latter are shown to display limited successes for the B(E2)'s but complete failures for the B(M1)'s, whereas calculations based on the full IBFM hamiltonian are in reasonable agreement with experiment for the two kinds of experimental data.

Naviliat-Cuncic, O.; Loiselet, M.; Vervier, J.

1990-07-01

94

Chromium–manganese iron alloy system design cast in metal and sand moulds for erosion resistance: a positron lifetime study  

Microsoft Academic Search

Erosion characteristics of high chromium (Cr, 16–19%) alloy cast iron with 5% and 10% manganese (Mn) prepared in metal and\\u000a sand moulds through induction melting are investigated using jet erosion test setup in both as-cast and heat-treated conditions.\\u000a The samples were characterised for hardness and microstructural properties. A new and novel non-destructive evaluation technique\\u000a namely positron lifetime spectroscopy has also

P. Sampathkumaran; C. Ranganathaiah; S. Seetharamu; Kishore

2011-01-01

95

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

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

Two-photon exchange measurements with positrons and electrons  

SciTech Connect

Two-photon exchange contributions have potentially broad ranging impact on several charged lepton scattering measurements. Previously believed to be extremely small, based in part on comparisons of positron scattering and electron scattering in the 1950s and 1960s, recent data suggest that the corrections may be larger than expected, in particular in kinematic regions that were inaccessible in these early positron scattering measurements. Additional measurements using positron beams at Jefferson Lab would allow for a detailed investigation of these contributions in a range of reactions and observables.

Arrington, John [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2009-09-02

98

Improved measurement of the lifetime of the ? lepton  

NASA Astrophysics Data System (ADS)

A new measurement of the ? lifetime is presented. It uses data collected with the Opal detector during 1994, which almost doubles the size of the opal ? sample. Two statistically independent techniques are used: an impact parameter analysis of one-prong decay tracks and a fit to the decay length distribution of three-prong decays. The lifetime obtained from the 1994 data by combining the results of these methods is ?? = 289.7 +/- 2.5 (stat) +/- 1.5 (sys) fs. When combined with the previous opal ? lifetime measurement the improved ? lifetime is ?? = 289.2 +/- 1.7 (stat.) +/- 1.2 (sys.) fs.

Alexander, G.; Allison, J.; Altekamp, N.; Ametewee, K.; Anderson, K. J.; Anderson, S.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Ball, A. H.; Barberio, E.; Barlow, R. J.; Bartoldus, R.; Batley, J. R.; Beaudoin, G.; Bechtluft, J.; Beeston, C.; Behnke, T.; Bell, A. N.; Bell, K. W.; Bella, G.; Bentvelsen, S.; Berlich, P.; Bethke, S.; Biebel, O.; Blobel, V.; Bloodworth, I. J.; Bloomer, J. E.; Bock, P.; Bosch, H. M.; Boutemeur, M.; Bouwens, B. T.; Braibant, S.; Bright-Thomas, P.; Brown, R. M.; Burckhart, H. J.; Burgard, C.; Bürgin, R.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlesworth, C.; Charlton, D. G.; Chrisman, D.; Chu, S. L.; Clarke, P. E. L.; Cohen, I.; Conboy, J. E.; Cooke, O. C.; Cuffiani, M.; Dado, S.; Dallapiccola, C.; Dallavalle, G. M.; Darling, C.; de Jong, S.; del Pozo, L. A.; Dixit, M. S.; Do Couto E Silva, E.; Doucet, M.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Edwards, J. E. G.; Estabrooks, P. G.; Evans, H. G.; Evans, M.; Fabbri, F.; Fath, P.; Fiedler, F.; Fierro, M.; Fischer, H. M.; Folman, R.; Fong, D. G.; Foucher, M.; Fukui, H.; Fürtjes, A.; Gagnon, P.; Gaidot, A.; Gary, J. W.; Gascon, J.; Gascon-Shotkin, S. M.; Geddes, N. I.; Geich-Gimbel, C.; Gensler, S. W.; Gentit, F. X.; Geralis, T.; Giacomelli, G.; Giacomelli, P.; Giacomelli, R.; Gibson, V.; Gibson, W. R.; Gingrich, D. M.; Goldberg, J.; Goodrick, M. J.; Gorn, W.; Grandi, C.; Gross, E.; Gruwé, M.; Hajdu, C.; Hanson, G. G.; Hansroul, M.; Hapke, M.; Hargrove, C. K.; Hart, P. A.; Hartmann, C.; Hauschild, M.; Hawkes, C. M.; Hawking, R.; Hemingway, R. J.; Herten, G.; Heuer, R. D.; Hildreth, M. D.; Hill, J. C.; Hillier, S. J.; Hilse, T.; Hobson, P. R.; Homer, R. J.; Honma, A. K.; Horváth, D.; Howard, R.; Hughes-Jones, R. E.; Hutchcroft, D. E.; Igo-Kemenes, P.; Imrie, D. C.; Ingram, M. R.; Jawahery, A.; Jeffreys, P. W.; Jeremie, H.; Jimack, M.; Joly, A.; Jones, G.; Jones, M.; Jones, R. W. L.; Jost, U.; Jovanovic, P.; Kanzaki, J.; Karlen, D.; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; King, J.; Kirk, J.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D. S.; Kokott, T. P.; Komamiya, S.; Kowalewski, R.; Kress, T.; Krieger, P.; von Krogh, J.; Kyberd, P.; Lafferty, G. D.; Lafoux, H.; Lahmann, R.; Lai, W. P.; Lanske, D.; Lauber, J.; Layter, J. G.; Lee, A. M.; Lefebvre, E.; Lellouch, D.; Letts, J.; Levinson, L.; Lewis, C.; Lloyd, S. L.; Loebinger, F. K.; Long, G. D.; Lorazo, B.; Losty, M. J.; Ludwig, J.; Luig, A.; Malik, A.; Mannelli, M.; Marcellini, S.; Markus, C.; Martin, A. J.; Martin, J. P.; Martinez, G.; Mashimo, T.; Matthews, W.; Mättig, P.; McDonald, W. J.; McKenna, J.; McKigney, E. A.; McMahon, T. J.; McNab, A. I.; Meijers, F.; Menke, S.; Merritt, F. S.; Mes, H.; Meyer, J.; Michelini, A.; Mikenberg, G.; Miller, D. J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Morii, M.; Müller, U.; Nellen, B.; Nijjhar, B.; Nisius, R.; O'Neale, S. W.; Oakham, F. G.; Odorici, F.; Ogren, H. O.; Omori, T.; Oreglia, M. J.; Orito, S.; Palazzo, M.; Pálinkás, J.; Pansart, J. P.; Pásztor, G.; Pater, J. R.; Patrick, G. N.; Pearce, M. J.; Petzold, S.; Pilcher, J. E.; Pinfold, J.; Plane, D. E.; Poffenberger, P.; Poli, B.; Posthaus, A.; Przysiezniak, H.; Rees, D. L.; Rigby, D.; Rison, M. G.; Robins, S. A.; Rodning, N.; Roney, J. M.; Rooke, A.; Ros, E.; Rossi, A. M.; Rosvick, M.; Routenburg, P.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D. R.; Rylko, R.; Sarkisyan, E. K. G.; Sasaki, M.; Sbarra, C.; Schaile, A. D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schenk, P.; Schmitt, B.; Schröder, M.; Schultz-Coulon, H. C.; Schulz, M.; Schütz, P.; Schwiening, J.; Scott, W. G.; Shears, T. G.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Sherwood, P.; Siroli, G. P.; Sittler, A.; Skillman, A.; Skuja, A.; Smith, A. M.; Smith, T. J.; Snow, G. A.; Sobie, R.; Söldner-Rembold, S.; Springer, R. W.; Sproston, M.; Stahl, A.; Starks, M.; Stephens, K.; Steuerer, J.; Stockhausen, B.; Strom, D.; Strumia, F.; Szymanski, P.; Tafirout, R.; Takeda, H.; Taras, P.; Tarem, S.; Tecchio, M.; Tesch, N.; Thiergen, M.; Thomson, M. A.; von Törne, E.; Towers, S.; Tscheulin, M.; Tsur, E.; Turcot, A. S.; Turner-Watson, M. F.; Utzat, P.; van Kooten, R.; Vasseur, G.; Verzocchi, M.; Vikas, P.; Vincter, M.; Vokurka, E. H.; Wäckerle, F.; Wagner, A.; Ward, C. P.; Ward, D. R.; Ward, J. J.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Weber, P.; Wells, P. S.; Wermes, N.; White, J. S.; Wilkens, B.; Wilson, G. W.; Wilson, J. A.; Wlodek, T.; Wolf, G.; Wotton, S.; Wyatt, T. R.; Xella, S.; Yamashita, S.; Yekutieli, G.; Yoshimura, K.; Zacek, V.

1996-02-01

99

Interpretation of microwave-detected photoconductance decay lifetime measurements  

Microsoft Academic Search

The microwave-detected photoconductance decay technique is potentially useful for its ability to make rapid, contactless measurements of carrier lifetimes. However, there are questions as to the effects of nonuniform excitation of the sample and resultant two-dimensional carrier distributions on the measured microwave reflectance transients, and therefore, the deduced carrier lifetimes. Also, it is not possible to nondestructively distinguish between bulk

F. P. Giles; R. J. Schwartz; J. L. Gray

1993-01-01

100

Positron annihilation studies of moisture in graphite-reinforced composites  

SciTech Connect

The positron lifetime technique of monitoring absorbed moisture is applied to several composites, including graphite/polymides which are candidates for high-temperature (over 260 C) applications. The experimental setup is a conventional fast-slow coincidence system wherein the positron lifetime is measured with respect to a reference time determined by the detection of a nuclear gamma ray emitted simultaneously with the positron. From the experiments, a rate of change of positron mean lifetime per unit mass of water can be determined for each type of specimen. Positron lifetime spectra are presented for a graphite/polyimide composite and for a pure polyimide.

Singh, J.J. (NASA, Langley Research Center, Hampton, Va.); Holt, W.H. (U.S. Navy, Naval Surface Weapons Center, Dahlgren, Va.); Mock, W., Jr. (Vought Corp., Dallas, Tex.)

1980-07-01

101

Cosmic-Ray Positron Energy Spectrum Measured by PAMELA.  

PubMed

Precision measurements of the positron component in the cosmic radiation provide important information about the propagation of cosmic rays and the nature of particle sources in our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy. The combined measurements of the cosmic-ray positron energy spectrum and fraction provide a unique tool to constrain interpretation models. During the recent solar minimum activity period from July 2006 to December 2009, approximately 24?500 positrons were observed. The results cannot be easily reconciled with purely secondary production, and additional sources of either astrophysical or exotic origin may be required. PMID:24010424

Adriani, O; Barbarino, G C; Bazilevskaya, G A; Bellotti, R; Bianco, A; Boezio, M; Bogomolov, E A; Bongi, M; Bonvicini, V; Bottai, S; Bruno, A; Cafagna, F; Campana, D; Carbone, R; Carlson, P; Casolino, M; Castellini, G; De Donato, C; De Santis, C; De Simone, N; Di Felice, V; Formato, V; Galper, A M; Karelin, A V; Koldashov, S V; Koldobskiy, S A; Krutkov, S Y; Kvashnin, A N; Leonov, A; Malakhov, V; Marcelli, L; Martucci, M; Mayorov, A G; Menn, W; Mergé, M; Mikhailov, V V; Mocchiutti, E; Monaco, A; Mori, N; Munini, R; Osteria, G; Palma, F; Papini, P; Pearce, M; Picozza, P; Pizzolotto, C; Ricci, M; Ricciarini, S B; Rossetto, L; Sarkar, R; Scotti, V; Simon, M; Sparvoli, R; Spillantini, P; Stochaj, S J; Stockton, J C; Stozhkov, Y I; Vacchi, A; Vannuccini, E; Vasilyev, G I; Voronov, S A; Yurkin, Y T; Zampa, G; Zampa, N; Zverev, V G

2013-08-19

102

NEUTRON LIFETIME MEASUREMENTS IN THE FAST REACTORS ZEUS AND ZEPHYR  

Microsoft Academic Search

Measurements of mean prompt neutron lifetime were made by a perturbation ; technique, by the use of a reactivity oscillator, and by the Rossi- alpha method ; in which the time correlation of fission chamber pulses is studied. The lifetime ; in Zeus was found to be 7 x 10⁻⁸ sec and in the graphite reflected version ; of Zephyr,

G. Ingram; D. B. McCulloch; J. E. Sanders

1959-01-01

103

Fluorescence lifetime measurements of boronate derivatives to determine glucose concentration  

Microsoft Academic Search

A novel investigation into the fluorescence lifetimes of molecules, both established and newly designed, was performed. These molecules are the basis of a continuous, minimally invasive, glucose sensor based on fluorescence lifetime measurements. This sensor, if coupled with an automated insulin delivery device, would effectively create an artificial pancreas allowing for the constant monitoring and control of glucose levels in

Gable

2000-01-01

104

A measurement of the lifetime of the tau lepton  

Microsoft Academic Search

The lifetime of the tau lepton has been measured by two independent methods using a silicon microvertex detector installed in the DELPHI detector. The signed impact parameter distribution of the one prong decays yielded a lifetime of tautau = 321 +\\/- 36 (stat.) +\\/- 16 (syst.) fs, while the decay length distribution of three prong decays gave the result tautau

P. Abreu; W. Adam; F. Adami; T. Adye; T. Akesson; G. D. Alekseev; P. Allen; S. Almehed; S. J. Alvsvaag; Ugo Amaldi; E G Anassontzis; P. Antilogus; W.-D. Apel; R.-J. Apsimon; B. Åsman; Pierre Astier; J.-E. Augustin; A. Augustinus; Paul Baillon; P. Bambade; F. Barao; Guido Barbiellini; Dimitri Yuri Bardin; A. Baroncelli; O. Barring; Walter Bartl; Marco Battaglia; M. J. Bates; M. Baubillier; K.-H. Becks; C. J. Beeston; M. Begalli; P. Beilliere; Yu A Belokopytov; P. Beltran; D. Benedic; J. M. Benlloch; M. Berggren; D. Bertrand; F. Bianchi; J. H. Bibby; M. S. Bilenky; P. Billoir; J. Bjarne; D. Bloch; S. Blyth; P. N. Bogolubov; T. Bolognese; M. Bonapart; M. Bonesini; W. Bonivento; P. S. L. Booth; M. Boratav; P. Borgeaud; G. Borisov; H. Borner; C. Bosio; B. Bostjancic; O. Botner; B. Bouquet; M. Bozzo; S. Braibant; P. Branchini; K. D. Brand; R. A. Brenner; C. Bricman; R. C. A. Brown; N. Brummer; J.-M. Brunet; L. Bugge; T. Buran; H. Burmeister; J. A. M. A. Buytaert; M. Caccia; M. Calvi; A. J. Camacho Rozas; J.-E. Campagne; A. Campion; T. Camporesi; V. Canale; F. Cao; F. Carena; L. Carroll; Carlo Caso; Edoardo Castelli; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; L. Cerrito; A. Chan; P. Charpentier; P. Checchia; G. A. Chelkov; L. Chevalier; P V Chliapnikov; V. Chorowicz; R. Cirio; M. P. Clara; P. Collins; J. L. Contreras; R. Contri; G. Cosme; F. Couchot; H. B. Crawley; D J Crennell; G. Crosetti; N. Crosland; M. Crozon; J. Cuevas Maestro; S. Czellar; S. Dagoret; Erik Dahl-Jensen; B. Dalmagne; M. Dam; G. Damgaard; G. Darbo; Evelyne Daubie; P. D. Dauncey; Martyn Davenport; P. David; A. de Angelis; M. de Beer; H. de Boeck; Wim de Boer; C. de Clercq; M. D. M. de Fez Laso; N. de Groot; C. de La Vaissiere; B. de Lotto; A. de Min; C. Defoix; D. Delikaris; S. Delorme; P A Delpierre; N. Demaria; J E Derkaoui; Lucia Di Ciaccio; H. Dijkstra; F. Djama; J. Dolbeau; M. Donszelmann; K. Doroba; M. Dracos; J. Drees; M. Dris; Y. Dufour; W. Dulinski; L.-O. Eek; Paule Anna Mari Eerola; T J C Ekelöf; Gösta Ekspong; A. Elliot Peisert; J.-P. Engel; V P Falaleev; D. Fassouliotis; M. Fernandez Alonso; A. Ferrer; T. A. Filippas; A. Firestone; H. Foeth; E. Fokitis; P. Folegati; F. Fontanelli; K. A. J. Forbes; H. Forsbach; B J Franek; P. Frenkiel; D E C Fries; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; K. Furnival; H. Furstenau; J A Fuster; J. M. Gago; G. Galeazzi; D. Gamba; C. Garcia; J. Garcia; U. Gasparini; P. Gavillet; E. N. Gazos; J.-P. Gerber; P. Giacomelli; K.-W. Glitza; R. Gokieli; V. M. Golovatyuk; J. J. Gomez Y Cadenas; A. Goobar; Gian P Gopal; M. Gorski; Valerio Gracco; A. Grant; F. Grard; E. Graziani; M.-H. Gros; G. Grosdidier; E. Gross; B. Grossetete; S A Gumenyuk; J. Guy; F. Hahn; M. Hahn; S. Haider; Z. Hajduk; A. Hakansson; A. Hallgren; K. Hamacher; G. Hamel de Monchenault; F. J. Harris; B. W. Heck; T. Henkes; I. Herbst; J. J. Hernandez; P. Herquet; H. Herr; I. Hietanen; C. O. Higgins; E. Higon; H. J. Hilke; S. D. Hodgson; T. Hofmokl; R. Holmes; S.-O. Holmgren; D. Holthuizen; P. F. Honore; J. E. Hooper; R. Horisberger; M. Houlden; J. Hrubec; P. O. Hulth; K. Hultqvist; D. Husson; B. D. Hyams; P. Ioannou; D. Isenhower; P.-S. Iversen; J. N. Jackson; P. Jalocha; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; D. Johnson; M. Jonker; L. Jonsson; P. Juillot; G. Kalkanis; G Kantardjian; F. Kapusta; S. Katsanevas; E. C. Katsoufis; R. Keranen; J. Kesteman; B. A. Khomenko; N. N. Khovanski; B. King; N. J. Kjaer; H. Klein; W. Klempt; A. Klovning; P. Kluit; J. H. Koehne; B. Koene; P. Kokkinias; M Koratzinos; M. Koratzinos; K. Korcyl; A. V. Korytov; B. Korzen; V. Kostukhin; C. Kourkoumelis; T. Kreuzberger; J. Krolikowski; U. Kruener-Marquis; W. Krupinski; W. Kucewicz; K. Kurvinen; C Lambropoulos; J. W. Lamsa; L. Lanceri; V. Lapin; J.-P. Laugier; R. Lauhakangas; G. Leder; F. Ledroit; J. Lemonne; G. Lenzen; V. Lepeltier; A. Letessier-Selvon; D. Liko; E Lillethun; J. Lindgren; A. Lipniacka; I. Lippi; R. Llosa; B. Loerstad; M. Lokajicek; J. G. Loken; M. A. Lopez Aguera; A. Lopez-Fernandez; M. Los; D. Loukas; A. Lounis; J. J. Lozano; R. Lucock; P. Lutz; L. Lyons; G. Maehlum; J. Maillard; A. Maltezos; S. Maltezos; F. Mandl; J. Marco; M. Margoni; J.-C. Marin; A. Markou; S. Marti; L. Mathis; F. Matorras; C. Matteuzzi; G. Matthiae; M Mazzucato; M. Mc Cubbin; R. Mc Nulty; E. Menichetti; G. Meola; C. Meroni; W. T. Meyer; M. Michelotto; W. A. Mitaroff; G. V. Mitselmakher; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; H. Muller; W. J. Murray; G. Myatt; F. Naraghi; U. Nau-Korzen; F. L. Navarria; P. Negri; B. S. Nielsen; B. Nijjhar; V. Nikolaenko; V. Obraztsov; A. G. Olshevski; R. Orava; A. Ostankov; A. Ouraou; R. Pain; H. Palka; T. Papadopoulou; L. Pape; A. Passeri; M. Pegoraro; V. Perevozchikov; M. Pernicka; A. Perrotta

1991-01-01

105

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

NASA Astrophysics Data System (ADS)

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 ? decay. The neutron lifetime obtained, 878.5±0.7stat±0.3sys s, is the most accurate experimental measurement to date.

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

2008-09-01

106

Quantitative carrier lifetime images optically measured on rough silicon wafers  

NASA Astrophysics Data System (ADS)

Results of optical carrier lifetime measurements like carrier density imaging significantly depend on surface conditions of the sample under test. Rough or textured surfaces have a severe impact on the measurement quality since they cause blurring and overestimation of the lifetime measurement. We propose a correction method for both, the adjustment of the absolute value and the restoration of the spatial distribution of the recombination lifetime. The absolute value is corrected by taking the emissivity of the sample into account. The unblurred signal distribution is obtained by mathematical deconvolution via Wiener filtering. For this purpose an appropriate point spread function is experimentally determined.

Schubert, Martin C.; Pingel, Sebastian; The, Manuel; Warta, Wilhelm

2007-06-01

107

Measurement of the Bs0 Lifetime Using Semileptonic Decays  

Microsoft Academic Search

We report a measurement of the Bs0 lifetime in the semileptonic decay channel Bs0-->Ds-mu+nuX (and its charge conjugate), using approximately 0.4fb-1 of data collected with the D0 detector during 2002 2004. Using 5176 reconstructed Ds-mu+ signal events, we have measured the Bs0 lifetime to be tau(Bs0)=1.398±0.044(stat)-0.025+0.028(syst)ps. This is the most precise measurement of the Bs0 lifetime to date.

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; M. S. Anzelc; Y. Arnoud; M. Arov; A. Askew; B. Åsman; A. C. S. Assis Jesus; O. Atramentov; C. Autermann; C. Avila; C. Ay; F. Badaud; A. Baden; L. Bagby; B. Baldin; D. V. Bandurin; P. Banerjee; S. Banerjee; E. Barberis; P. Bargassa; P. Baringer; C. Barnes; J. Barreto; J. F. Bartlett; U. Bassler; D. Bauer; A. Bean; M. Begalli; C. Belanger-Champagne; A. Bellavance; J. A. Benitez; S. B. Beri; G. Bernardi; R. Bernhard; L. Berntzon; 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; K. Bloom; 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; D. Brown; N. J. Buchanan; D. Buchholz; M. Buehler; V. Buescher; S. Burdin; S. Burke; T. H. Burnett; E. Busato; C. P. Buszello; J. M. Butler; S. Calvet; J. Cammin; S. Caron; M. A. Carrasco-Lizarraga; 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; F. Chevallier; D. K. Cho; S. Choi; B. Choudhary; L. Christofek; D. Claes; B. Clément; C. Clément; Y. Coadou; M. Cooke; W. E. Cooper; D. Coppage; M. Corcoran; M.-C. Cousinou; B. Cox; S. Crépé-Renaudin; D. Cutts; M. Cwiok; H. da Motta; A. Das; 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; 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; A. Dominguez; H. Dong; 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; J. Estrada; H. Evans; A. Evdokimov; V. N. Evdokimov; S. N. Fatakia; L. Feligioni; A. V. Ferapontov; T. Ferbel; F. Fiedler; F. Filthaut; W. Fisher; H. E. Fisk; I. Fleck; M. Ford; 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; C. E. Gerber; Y. Gershtein; D. Gillberg; G. Ginther; N. Gollub; B. Gómez; K. Gounder; A. Goussiou; P. D. Grannis; H. Greenlee; Z. D. Greenwood; E. M. Gregores; G. Grenier; Ph. Gris; J.-F. Grivaz; S. Grünendahl; M. W. Grünewald; F. Guo; J. Guo; G. Gutierrez; P. Gutierrez; A. Haas; N. J. Hadley; P. Haefner; S. Hagopian; J. Haley; I. Hall; R. E. Hall; L. Han; K. Hanagaki; K. Harder; A. Harel; R. Harrington; J. M. Hauptman; R. Hauser; J. Hays; T. Hebbeker; D. Hedin; J. G. Hegeman; 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; V. Hynek; I. Iashvili; R. Illingworth; A. S. Ito; S. Jabeen; M. Jaffré; S. Jain; K. Jakobs; C. Jarvis; A. Jenkins; R. Jesik; K. Johns; C. Johnson; M. Johnson; A. Jonckheere; P. Jonsson; A. Juste; D. Käfer; S. Kahn; E. Kajfasz; A. M. Kalinin; J. M. Kalk; J. R. Kalk; S. Kappler; D. Karmanov; J. Kasper; I. Katsanos; D. Kau; R. Kaur; R. Kehoe; S. Kermiche; S. Kesisoglou; A. Khanov; A. Kharchilava; Y. M. Kharzheev; D. Khatidze; H. Kim; T. J. Kim; M. H. Kirby; 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; T. Kuhl; A. Kumar; S. Kunori; A. Kupco; T. Kurca; J. Kvita; S. Lager; S. Lammers; G. Landsberg; J. Lazoflores; A.-C. Le Bihan; P. Lebrun; W. M. Lee; A. Leflat; F. Lehner; C. Leonidopoulos; V. Lesne; J. Leveque; P. Lewis; J. Li; Q. Z. Li; J. G. R. Lima; D. Lincoln; J. Linnemann; V. V. Lipaev; R. Lipton; Z. Liu; L. Lobo; A. Lobodenko; M. Lokajicek; A. Lounis; P. Love; H. J. Lubatti; 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; R. McCarthy; R. McCroskey; D. Meder; A. Melnitchouk; A. Mendes; L. Mendoza; M. Merkin; K. W. Merritt; A. Meyer; J. Meyer; M. Michaut; H. Miettinen; T. Millet; J. Mitrevski; J. Molina; N. K. Mondal; J. Monk; R. W. Moore; T. Moulik; G. S. Muanza; M. Mulders; M. Mulhearn; 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; V. O'Dell; D. C. O'Neil; G. Obrant; V. Oguri; N. Oliveira; N. Oshima; R. Otec; G. J. Otero Y Garzón; M. Owen; P. Padley

2006-01-01

108

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

109

Lifetime measurement of excited states in 109Cd  

NASA Astrophysics Data System (ADS)

The levels up to 1135 keV in 109Cd were excited via 109Ag(p, n?) reaction. For the first time, the lifetimes of energy levels at 673, 721, 821, 891, 997, 1106, and 1135 keV have been measured using Doppler shift attenuation technique. NUCLEAR REACTION 109Ag(p, n?), Ep=3.4 and 3.9 MeV; measured lifetime; DSA technique.

Avasthi, D. K.; Mittal, V. K.; Govil, I. M.

1982-09-01

110

Improved measurements of the B0 and B+ meson lifetimes  

NASA Astrophysics Data System (ADS)

Updated measurements of the B0 and B+ meson lifetimes are presented. From a data sample of 1.72 million hadronic Z0 decays recorded during the period 1991 to 1993, a sample of approximately 1000 semileptonic B meson decays containing a D0, D+ or D*+ has been isolated. From the distribution of decay times in the different samples the lifetimes of the B0 and B+ mesons are determined to be 1.53±0.12±0.08 ps and 1.52±0.14±0.09 ps, respectively, where the first error is statistical and the second systematic. The ratio of the B+ to B0 lifetimes is measured to be 0.99±0.14{-0.04/+0.05}, confirming expectations that the lifetimes are similar.

Akers, R.; Alexander, G.; Allison, J.; Ametewee, K.; Anderson, K. J.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Ball, A. H.; Barberio, E.; Barlow, R. J.; Bartoldus, R.; Batley, J. R.; Beaudoin, G.; Beck, A.; Beck, G. A.; Beeston, C.; Behnke, T.; Bell, K. W.; Bella, G.; Bentvelsen, S.; Berlich, P.; Bethke, S.; Biebel, O.; Bloodworth, I. J.; Bock, P.; Bosch, H. M.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brown, R. M.; Buijs, A.; Burckhart, H. J.; Bürgin, R.; Burgard, C.; Capdevielle, N.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlesworth, C.; Charlton, D. G.; Chu, S. L.; Clarke, P. E. L.; Clayton, J. C.; Clowes, S. G.; Cohen, I.; Conboy, J. E.; Cooke, O. C.; Cuffiani, M.; Dado, S.; Dallapiccola, C.; Dallavalle, G. M.; Darling, C.; de Jong, S.; Del Pozo, L. A.; Deng, H.; Dittmar, M.; Dixit, M. S.; Do Couto E Silva, E.; Duboscq, J. E.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Dunwoody, U. C.; Edwards, J. E. G.; Elcombe, P. A.; Estabrooks, P. G.; Etzion, E.; Evans, H. G.; Fabbri, F.; Fabbro, B.; Fanti, M.; Fath, P.; Fierro, M.; Fincke-Keeler, M.; Fischer, H. M.; Fischer, P.; Folman, R.; Fong, D. G.; Foucher, M.; Fukui, H.; Fürtjes, A.; Gagnon, P.; Gaidot, A.; Gary, J. W.; Gascon, J.; Geddes, N. I.; Geich-Gimbel, C.; Gensler, S. W.; Gentit, F. X.; Geralis, T.; Giacomelli, G.; Giacomelli, P.; Giacomelli, R.; Gibson, V.; Gibson, W. R.; Gillies, J. D.; Goldberg, J.; Gingrich, D. M.; Goodrick, M. J.; Gorn, W.; Grandi, C.; Gross, E.; Hagemann, J.; Hanson, G. G.; Hansroul, M.; Hargrove, C. K.; Hart, P. A.; Hauschild, M.; Hawkes, C. M.; Heflin, E.; Hemingway, R. J.; Herten, G.; Heuer, R. D.; Hill, J. C.; Hillier, S. J.; Hilse, T.; Hobson, P. R.; Hochman, D.; Homer, R. J.; Honma, A. K.; Howard, R.; Hughes-Jones, R. E.; Igo-Kemenes, P.; Imrie, D. C.; Jawahery, A.; Jeffreys, P. W.; Jeremie, H.; Jimack, M.; Jones, M.; Jones, R. W. L.; Jovanovic, P.; Jui, C.; Karlen, D.; Kanzaki, J.; Kawagoe, K.; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; King, B.; King, J.; Kirk, J.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D. S.; Kokott, T. P.; Komamiya, S.; Kowalewski, R.; Kress, T.; Krieger, P.; von Krogh, J.; Kyberd, P.; Lafferty, G. D.; Lafoux, H.; Lahmann, R.; Lai, W. P.; Lauber, J.; Layter, J. G.; Leblanc, P.; Lee, A. M.; Lefebvre, E.; Lellouch, D.; Leroy, C.; Letts, J.; Levinson, L.; Lloyd, S. L.; Loebinger, F. K.; Long, G. D.; Lorazo, B.; Losty, M. J.; Lou, X. C.; Ludwig, J.; Luig, A.; Mannelli, M.; Marcellini, S.; Markus, C.; Martin, A. J.; Martin, J. P.; Mashimo, T.; Matthews, W.; Mättig, P.; Maur, U.; McKenna, J.; McMahon, T. J.; McNab, A. I.; Meijers, F.; Merritt, F. S.; Mes, H.; Michelini, A.; Middleton, R. P.; Mikenberg, G.; Miller, D. J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Morii, M.; Müller, U.; Nellen, B.; Nijjhar, B.; O'Neale, S. W.; Oakham, F. G.; Odorici, F.; Ogren, H. O.; Oldershaw, N. J.; Oram, C. J.; Oreglia, M. J.; Orito, S.; Palmonari, F.; Pansart, J. P.; Patrick, G. N.; Pearce, M. J.; Phillips, P. D.; Pilcher, J. E.; Pinfold, J.; Plane, D. E.; Poffenberger, P.; Poli, B.; Posthaus, A.; Pritchard, T. W.; Przysiezniak, H.; Redmond, M. W.; Rees, D. L.; Rigby, D.; Rison, M. G.; Robins, S. A.; Robinson, D.; Rodning, N.; Roney, J. M.; Ros, E.; Rossi, A. M.; Rosvick, M.; Routenburg, P.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D. R.; Sasaki, M.; Sbarra, C.; Schaile, A. D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schenk, P.; Schmitt, B.; Schröder, M.; Schultz-Coulon, H. C.; Schütz, P.; Schulz, M.; Schwick, C.; Schwiening, J.; Scott, W. G.; Settles, M.; Shears, T. G.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Sherwood, P.; Siroli, G. P.; Skillman, A.; Skuja, A.; Smith, A. M.; Smith, T. J.; Snow, G. A.; Sobie, R.; Söldner-Rembold, S.; Springer, R. W.; Sproston, M.; Stahl, A.; Starks, M.; Stegmann, C.; Stephens, K.; Steuerer, J.; Stockhausen, B.; Strom, D.; Szymanski, P.; Tafirout, R.; Takeda, H.; Takeshita, T.; Taras, P.; Tarem, S.; Tecchio, M.; Teixeira-Dias, P.; Tesch, N.; Thomson, M. A.; Tousignant, O.; Towers, S.; Tscheulin, M.; Tsukamoto, T.; Turcot, A. S.; Turner-Watson, M. F.; Utzat, P.; van Kooten, R.; Vasseur, G.; Vikas, P.; Vincter, M.; Wagner, A.; Wagner, D. L.; Ward, C. P.; Ward, D. R.; Ward, J. J.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Weber, P.; Wells, P. S.; Wermes, N.; Wilkens, B.; Wilson, G. W.; Wilson, J. A.; Winterer, V.-H.; Wlodek, T.; Wolf, G.; Wotton, S.; Wyatt, T. R.; Yeaman, A.; Yekutieli, G.; Yurko, M.; Zacek, V.; Zeuner, W.; Zorn, G. T.

1995-09-01

111

Precision Measurement of the ?b0 Baryon Lifetime  

NASA Astrophysics Data System (ADS)

The ratio of the ?b0 baryon lifetime to that of the B¯0 meson is measured using 1.0fb-1 of integrated luminosity in 7 TeV center-of-mass energy pp collisions at the LHC. The ?b0 baryon is observed for the first time in the decay mode ?b0?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 ?b0 lifetime is found to be 1.482±0.018±0.012ps. In both cases, the first uncertainty is statistical and the second systematic.

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., Jr.; 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.

2013-09-01

112

Uncertainty analysis in lifetime measurement for white light emitting diodes  

NASA Astrophysics Data System (ADS)

Lifetime is one of the most important characteristics of white LEDs for the solid state lighting industry and end users. The measurement uncertainties should be controlled well to ensure consistent measurement results. This paper gives uncertainty analysis in the measurement for the L50 lifetime of white LEDs. The exponential model is assumed for LEDs' light output degradation, and an Eyring model is used for accelerated life test. The influences of photometric measurement instruments, measurement duration and interval, junction temperature, input current, current accelerating index and activation energy are analysed. The analysis method introduced in this paper can be referenced for other related analysis, and the results are important to the practices in LED lifetime measurement.

Shen, Haiping; Zhou, Xiaoli; Zhang, Wanlu; Liu, Muqing

2012-10-01

113

Improved measurements of the B 0 and B + meson lifetimes  

Microsoft Academic Search

Updated measurements of the B0 and B+ meson lifetimes are presented. From a data sample of 1.72 million hadronic Z0 decays recorded during the period 1991 to 1993, a sample of approximately 1000 semileptonic B meson decays containing a D0, D+ or D*+ has been isolated. From the distribution of decay times in the different samples the lifetimes of the

R J Akers; Gideon Alexander; J. Allison; K A Ametewee; K. J. Anderson; S. Arcelli; S. Asai; D A Axen; Georges Azuelos; A. H. Ball; E. Barberio; R. J. Barlow; R. Bartoldus; J Richard Batley; G. Beaudoin; A. Beck; G. A. Beck; C. Beeston; T. Behnke; K. W. Bell; G. Bella; Stanislaus Cornelius Maria Bentvelsen; P. Bright-Thomas; Siegfried Bethke; O. Biebel; Ian J Bloodworth; P. Bock; H. M. Bosch; M. Boutemeur; S. Braibant; R. M. Brown; A. Buijs; Helfried J Burckhart; R. Bürgin; C. Burgard; N. Capdevielle; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; C. Charlesworth; D. G. Charlton; S. L. Chu; P. E. L. Clarke; J. C. Clayton; S. G. Clowes; I. Cohen; J. E. Conboy; O. C. Cooke; M. Cuffiani; S. Dado; C. Dallapiccola; G. M. Dallavalle; C L Darling; S. De Jong; L. A. del Pozo; H. Deng; Michael Dittmar; M. S. Dixit; E. do Couto e Silva; J. E. Duboscq; E. Duchovni; G. Duckeck; I. P. Duerdoth; U. C. Dunwoody; J. E. G. Edwards; P. A. Elcombe; P. G. Estabrooks; E. Etzion; H. G. Evans; Franco Luigi Fabbri; B. Fabbro; M. Fanti; P. Fath; M. Fierro; Margret Fincke-Keeler; H. M. Fischer; P. Fischer; R. Folman; D. G. Fong; M. Foucher; H. Fukui; A. Fürtjes; P. Gagnon; A. Gaidot; J. W. Gary; J. Gascon; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; T. Geralis; G. Giacomelli; P. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; James D Gillies; J. Goldberg; D. M. Gingrich; M. J. Goodrick; W. Gorn; C. Grandi; E. Gross; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. A. Hart; M. Hauschild; C. M. Hawkes; E. Heflin; Richard J Hemingway; G. Herten; R. D. Heuer; J. C. Hill; S. J. Hillier; T. Hilse; P. R. Hobson; D. Hochman; R James Homer; A. K. Honma; R. Howard; R. E. Hughes-Jones; P. Igo-Kemenes; D. C. Imrie; A. Jawahery; P. W. Jeffreys; H. Jeremie; Martin Paul Jimack; M. Jones; R. W. L. Jones; P. Jovanovic; C. Jui; D A Karlen; J I Kanzaki; K. Kawagoe; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; B J King; J. King; J. Kirk; S. Kluth; T. Kobayashi; M. Kobel; D. S. Koetke; T. P. Kokott; S. Komamiya; R V Kowalewski; T. Kress; P. Krieger; J. von Krogh; P. Kyberd; G. D. Lafferty; H. Lafoux; R. Lahmann; W. P. Lai; J. Lauber; J. G. Layter; P. Leblanc; A. M. Lee; E. Lefebvre; Daniel Lellouch; C. Leroy; J. Letts; L. Levinson; S. L. Lloyd; F. K. Loebinger; G. D. Long; B. Lorazo; Michael J Losty; X. C. Lou; J. Ludwig; A. Luig; M. Mannelli; S. Marcellini; C. Markus; A. J. Martin; J. P. Martin; T. Mashimo; W. Matthews; P. Mättig; U. Maur; J A McKenna; T. J. McMahon; A. I. McNab; F. Meijers; F. S. Merritt; H. Mes; Aldo Michelini; R. P. Middleton; G. Mikenberg; D. J. Miller; R. Mir; W. Mohr; A. Montanari; T. Mori; M. Morii; U. Müller; B. Nellen; B. Nijjhar; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; N. J. Oldershaw; C. J. Oram; M. J. Oreglia; S. Orito; F. Palmonari; J. P. Pansart; G. N. Patrick; M. J. Pearce; P. D. Phillips; J. E. Pilcher; J L Pinfold; D. E. Plane; P R Poffenberger; B. Poli; A. Posthaus; T. W. Pritchard; H. Przysiezniak; M. W. Redmond; D. L. Rees; D. Rigby; M. G. Rison; S. A. Robins; D. Robinson; N L Rodning; J. M. Roney; E. Ros; A. M. Rossi; M. Rosvick; P. Routenburg; Y. Rozen; K. Runge; O. Runolfsson; D. R. Rust; M. Sasaki; C. Sbarra; A. D. Schaile; O. Schaile; F. Scharf; P. Scharff-Hansen; P. Schenk; B. Schmitt; M. Schröder; H. C. Schultz-Coulon; P. Schütz; M. Schulz; C. Schwick; J. Schwiening; W. G. Scott; M. Settles; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; G. P. Siroli; A. Skillman; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; Randall J Sobie; S. Söldner-Rembold; R. W. Springer; M. Sproston; A. Stahl; M. Starks; C. Stegmann; K. Stephens; J. Steuerer; B. Stockhausen; D. Strom; P. Szymanski; R. Tafirout; H. Takeda; T. Takeshita; P. Taras; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; M. A. Thomson; O. Tousignant; S. Towers; M. Tscheulin; T. Tsukamoto; A. S. Turcot; M. F. Turner-Watson; P. Utzat; R. Van Kooten; G. Vasseur; P. Vikas; M G Vincter; A. Wagner; D. L. Wagner; C. P. Ward; D. R. Ward; J. J. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; P. Weber; P. S. Wells; N. Wermes; B. Wilkens; G. W. Wilson; J. A. Wilson; V. H. Winterer; T. Wlodek; G. Wolf; S A Wotton; T. R. Wyatt; A. Yeaman; G. Yekutieli; M. Yurko; V. Zacek; W. Zeuner; G. T. Zorn

1995-01-01

114

A measurement of the average bottom hadron lifetime  

Microsoft Academic Search

The average b hadron lifetime, $\\\\tau_{{\\\\rm b}}$, has been measured using approximately 3.5 million hadronic events collected with the OPAL detector at LEP between 1991 and 1994. A lifetime tag based on a neural network algorithm was used to select ${\\\\rm Z}^0\\\\rightarrow {\\\\rm b\\\\bar b}$ events. A secondary vertex reconstructed on the opposite side from the b-tag was used to

Gideon Alexander; J Allison; N Altekamp; K A Ametewee; K J Anderson; S. Anderson; S. Arcelli; S. Asai; D A Axen; Georges Azuelos; A H Ball; E Barberio; R J Barlow; R Bartoldus; J Richard Batley; J Bechtluft; C Beeston; T Behnke; A N Bell; K W Bell; G Bella; Stanislaus Cornelius Maria Bentvelsen; P Berlich; Siegfried Bethke; O Biebel; Volker Blobel; Ian J Bloodworth; J E Bloomer; M Bobinski; P Bock; H M Bosch; M Boutemeur; B T Bouwens; S Braibant; R M Brown; Helfried 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; M Cuffiani; S Dado; C Dallapiccola; G M Dallavalle; S De Jong; L A del Pozo; Klaus Desch; M S Dixit; E do Couto e Silva; M Doucet; E Duchovni; G Duckeck; I P Duerdoth; J E G Edwards; P G Estabrooks; H G Evans; M Evans; Franco Luigi Fabbri; P Fath; F Fiedler; M Fierro; H M Fischer; R Folman; D G Fong; M Foucher; A Fürtjes; P Gagnon; A Gaidot; J W Gary; J Gascon; S M Gascon-Shotkin; N I Geddes; C Geich-Gimbel; F X Gentit; T Geralis; G Giacomelli; P Giacomelli; R Giacomelli; V Gibson; W R Gibson; D M Gingrich; D A Glenzinski; J Goldberg; M J Goodrick; W Gorn; C Grandi; E Gross; Jacob 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; Richard J Hemingway; M Herndon; G Herten; R D Heuer; M D Hildreth; J C Hill; S J Hillier; T Hilse; P R Hobson; R James Homer; A K Honma; D Horváth; R Howard; R E Hughes-Jones; D E Hutchcroft; P Igo-Kemenes; D C Imrie; M R Ingram; K Ishii; A Jawahery; P W Jeffreys; H Jeremie; Martin Paul Jimack; A Joly; C R Jones; G Jones; M Jones; R W L Jones; U Jost; P Jovanovic; T R Junk; D A Karlen; K Kawagoe; T Kawamoto; Richard K Keeler; R G Kellogg; B W Kennedy; B J King; J Kirk; 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; H Lafoux; R Lahmann; W P Lai; D Lanske; J Lauber; S R Lautenschlager; J G Layter; D Lazic; A M Lee; E Lefebvre; Daniel Lellouch; J Letts; L Levinson; C Lewis; S L Lloyd; F K Loebinger; G D Long; Michael J Losty; J Ludwig; A Malik; M Mannelli; S Marcellini; C Markus; A J Martin; J P Martin; G Martínez; T Mashimo; W Matthews; P Mättig; W J McDonald; J A McKenna; E A McKigney; T J McMahon; A I McNab; R A McPherson; F Meijers; S Menke; F S Merritt; H Mes; J Meyer; Aldo Michelini; G Mikenberg; D J Miller; R Mir; W Mohr; A Montanari; T Mori; M Morii; U Müller; K Nagai; I Nakamura; H A Neal; B Nellen; B Nijjhar; R Nisius; S W O'Neale; F G Oakham; F Odorici; H O Ögren; N J Oldershaw; T Omori; M J Oreglia; S Orito; J Pálinkás; G Pásztor; J R Pater; G N Patrick; J Patt; M J Pearce; S Petzold; P Pfeifenschneider; J E Pilcher; J L Pinfold; D E Plane; P R Poffenberger; B Poli; A Posthaus; H Przysiezniak; D L Rees; D Rigby; S Robertson; S A Robins; N L Rodning; J M Roney; A M Rooke; E Ros; A M Rossi; M Rosvick; P Routenburg; Y Rozen; K Runge; O Runólfsson; U Ruppel; D R Rust; R Rylko; K Sachs; E Sarkisyan-Grinbaum; M Sasaki; C Sbarra; A D Schaile; O Schaile; F Scharf; P Scharff-Hansen; P Schenk; B Schmitt; S Schmitt; M Schröder; H C Schultz-Coulon; M Schulz; M Schumacher; P Schütz; 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; T J Smith; G A Snow; Randall J Sobie; S Söldner-Rembold; R W Springer; M Sproston; A Stahl; M Steiert; K Stephens; J Steuerer; B Stockhausen; D Strom; F Strumia; P Szymanski; R Tafirout; S D Talbot; S Tanaka; P Taras; S Tarem; M Thiergen; M A Thomson; E Von Törne; S Towers; I Trigger; T Tsukamoto; E Tsur; A S Turcot; M F Turner-Watson; P Utzat; R Van Kooten; G Vasseur; M Verzocchi; P Vikas; M G Vincter; E H Vokurka; F Wäckerle; A Wagner; C P Ward; D R Ward; J J 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; G Wolf; S A Wotton; T R Wyatt; S Yamashita; G Yekutieli; V Zacek

1997-01-01

115

Measurement of the lifetime of the tau lepton  

Microsoft Academic Search

The tau lepton lifetime is measured with the L3 detector at LEP using the complete data taken at centre-of-mass energies around the Z pole resulting in ??=293.2±2.0(stat)±1.5(syst)fs. The comparison of this result with the muon lifetime supports lepton universality of the weak charged current at the level of six per mille. Assuming lepton universality, the value of the strong coupling

M. Acciarri; P. Achard; O. Adriani; M. Aguilar-Benitez; J. Alcaraz; G. Alemanni; J. Allaby; A. Aloisio; M. G. Alviggi; G. Ambrosi; H. Anderhub; V. P. Andreev; T. Angelescu; F. Anselmo; A. Arefiev; T. Azemoon; T. Aziz; P. Bagnaia; A. Bajo; L. Baksay; A. Balandras; S. Banerjee; A. Barczyk; R. Barillère; L. Barone; P. Bartalini; M. Basile; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; L. Bellucci; R. Berbeco; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; S. Bhattacharya; M. Biasini; A. Biland; J. J. Blaising; S. C. Blyth; G. J. Bobbink; A. Böhm; L. Boldizsar; B. Borgia; D. Bourilkov; M. Bourquin; S. Braccini; J. G. Branson; V. Brigljevic; F. Brochu; A. Buffini; A. Buijs; J. D. Burger; W. J. Burger; 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; F. Cesaroni; M. Chamizo; Y. H. Chang; U. K. Chaturvedi; M. Chemarin; A. Chen; G. Chen; H. F. Chen; H. S. Chen; G. Chiefari; L. Cifarelli; F. Cindolo; C. Civinini; I. Clare; R. Clare; G. Coignet; A. P. Colijn; N. Colino; S. Costantini; F. Cotorobai; B. Cozzoni; B. de la Cruz; A. Csilling; S. Cucciarelli; T. S. Dai; J. A. van Dalen; R. D'Alessandro; R. de Asmundis; P. Déglon; A. Degré; K. Deiters; D. della Volpe; P. Denes; F. DeNotaristefani; A. De Salvo; M. Diemoz; D. van Dierendonck; F. Di Lodovico; C. Dionisi; M. Dittmar; A. Dominguez; A. Doria; M. T. Dova; D. Duchesneau; D. Dufournaud; P. Duinker; I. Duran; H. El Mamouni; A. Engler; F. J. Eppling; F. C. Erné; P. Extermann; M. Fabre; R. Faccini; M. A. Falagan; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; F. Ferroni; H. Fesefeldt; E. Fiandrini; J. H. Field; F. Filthaut; P. H. Fisher; I. Fisk; G. Forconi; L. Fredj; K. Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. S. Gau; S. Gentile; N. Gheordanescu; S. Giagu; Z. F. Gong; G. Grenier; O. Grimm; M. W. Gruenewald; M. Guida; R. van Gulik; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; A. Hasan; D. Hatzifotiadou; T. Hebbeker; A. Hervé; P. Hidas; J. Hirschfelder; H. Hofer; G. Holzner; H. Hoorani; S. R. Hou; Y. Hu; I. Iashvili; B. N. Jin; L. W. Jones; P. de Jong; I. Josa-Mutuberr??a; R. A. Khan; M. Kaur; M. N. Kienzle-Focacci; D. Kim; J. K. Kim; J. Kirkby; D. Kiss; W. Kittel; A. Klimentov; A. C. König; A. Kopp; V. Koutsenko; M. Kräber; R. W. Kraemer; W. Krenz; A. Krüger; A. Kunin; P. Ladron de Guevara; I. Laktineh; G. Landi; K. Lassila-Perini; M. Lebeau; A. Lebedev; P. Lebrun; P. Lecomte; P. Lecoq; P. Le Coultre; H. J. Lee; J. M. Le Goff; R. Leiste; E. Leonardi; P. Levtchenko; C. Li; S. Likhoded; C. H. Lin; W. T. Lin; F. L. Linde; L. Lista; Z. A. Liu; W. Lohmann; E. Longo; Y. S. Lu; K. Lübelsmeyer; C. Luci; D. Luckey; L. Lugnier; L. Luminari; W. Lustermann; W. G. Ma; M. Maity; L. Malgeri; A. Malinin; C. Maña; D. Mangeol; J. Mans; P. Marchesini; G. Marian; J. P. Martin; F. Marzano; G. G. G. Massaro; K. Mazumdar; R. R. McNeil; S. Mele; L. Merola; M. Meschini; W. J. Metzger; M. von der Mey; A. Mihul; H. Milcent; G. Mirabelli; J. Mnich; G. B. Mohanty; P. Molnar; B. Monteleoni; R. Moore; T. Moulik; G. S. Muanza; F. Muheim; A. J. M. Muijs; M. Musy; M. Napolitano; F. Nessi-Tedaldi; H. Newman; T. Niessen; A. Nisati; H. Nowak; G. Organtini; A. Oulianov; C. Palomares; D. Pandoulas; S. Paoletti; P. Paolucci; R. Paramatti; H. K. Park; I. H. Park; G. Pascale; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; M. Pedace; S. Pensotti; D. Perret-Gallix; B. Petersen; D. Piccolo; F. Pierella; M. Pieri; P. A. Piroué; E. Pistolesi; V. Plyaskin; M. Pohl; V. Pojidaev; H. Postema; J. Pothier; N. Produit; D. Prokofiev; J. Quartieri; G. Rahal-Callot; M. A. Rahaman; P. Raics; N. Raja; R. Ramelli; P. G. Rancoita; A. Raspereza; G. Raven; P. Razis; D. Ren; M. Rescigno; S. Reucroft; T. van Rhee; S. Riemann; K. Riles; A. Robohm; J. Rodin; B. P. Roe; L. Romero; A. Rosca; S. Rosier-Lees; J. A. Rubio; D. Ruschmeier; H. Rykaczewski; S. Saremi; S. Sarkar; J. Salicio; E. Sanchez; M. P. Sanders; M. E. Sarakinos; C. Schäfer; V. Schegelsky; S. Schmidt-Kaerst; D. Schmitz; H. Schopper; D. J. Schotanus; G. Schwering; C. Sciacca; D. Sciarrino; A. Seganti; L. Servoli; S. Shevchenko; N. Shivarov; V. Shoutko; E. Shumilov; A. Shvorob; T. Siedenburg; D. Son; B. Smith; P. Spillantini; M. Steuer; D. P. Stickland; A. Stone; B. Stoyanov; A. Straessner; K. Sudhakar; G. Sultanov; L. Z. Sun; H. Suter; J. D. Swain; Z. Szillasi; T. Sztaricskai; X. W. Tang; L. Tauscher; L. Taylor; B. Tellili; C. Timmermans; Samuel C. C. Ting; S. M. Ting; S. C. Tonwar; J. Tóth; C. Tully; K. L. Tung; Y. Uchida; J. Ulbricht; E. Valente; G. Vesztergombi; I. Vetlitsky; D. Vicinanza; G. Viertel; S. Villa; M. Vivargent; S. Vlachos; I. Vodopianov; H. Vogel; H. Vogt; I. Vorobiev; A. A. Vorobyov

2000-01-01

116

A precise measurement of the average b hadron lifetime  

NASA Astrophysics Data System (ADS)

An improved measurement of the average b hadron lifetime is performed using a sample of 1.5 million hadronic Z decays, collected during the 1991-1993 runs of ALEPH, with the silicon vertex detector fully operational. This uses the three-dimensional impact parameter distribution of lepton tracks coming from semileptonic b decays and yields an averageb hadron lifetime of 1.533 +/- 0.013 +/- 0.022 ps.

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

1996-02-01

117

A preliminary measurement of the average B hadron lifetime  

Microsoft Academic Search

The average B hadron lifetime was measured using data collected with the SLD detector at the SLC in 1993. From a sample of (approximately)50,000 Z(sup 0) events, a sample enriched in Z(sup 0) (yields) b(bar b) was selected by applying an impact parameter tag. The lifetime was extracted from the decay length distribution of inclusive vertices reconstructed in three dimensions.

Steven L. Manly; K Abe; I Abt; T Akagi; William W Ash; D Aston; N Bacchetta; K G Baird; C Baltay; H R Band; M B Barakat; G J Baranko; O Bardon; Timothy L Barklow; A O Bazarko; R Ben-David; Alberto C Benvenuti; T Bienz; 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 H 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 de Oliveira; C J S Damerell; S Dasu; R De Sangro; P De Simone; R Dell'Orso; M Dima; P Y C Du; R Dubois; B I Eisenstein; R Elia; D Falciai; C Fan; M J Fero; R Frey; K Furuno; T Gillman; G E Gladding; S González; G D Hallewell; E L Hart; Y Hasegawa; S J Hedges; S S Hertzbach; M D Hildreth; J Huber; M E Huffer; E W Hughes; H Hwang; Y Iwasaki; P Jacques; J A Jaros; A S Johnson; J R Johnson; R A Johnson; T R Junk; R Kajikawa; M S Kalelkar; I Karliner; H Kawahara; H W Kendall; 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 G S Leith; X Liu; M Loreti; A Lu; H L Lynch; J Ma; G Mancinelli; G C 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 Müller; T Nagamine; U Nauenberg; H A Neal; M Nussbaum; Y Ohnishi; L S Osborne; R S Panvini; T J Pavel; I Peruzzi; L Pescara; 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; P E Rensing; L S Rochester; J E Rothberg; P C Rowson; J J Russell; O H Saxton; T L Schalk; R H Schindler; U Schneekloth; B A Schumm; A Seiden; S Sen; M H Saevitz; J T Shank; G Shapiro; S L Shapiro; D J Sherden; C Simopoulos; S R Smith; N B Sinev; J A Snyder; M D Sokoloff; P E 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; A Yu Tolstykh; E Torrence; J Turk; T Usher; J Vavra; C Vannini; E N Vella; J P Venuti; P G Verdini; S R Wagner; A P Waite; S J Watts; A W Weidemann; 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 Q Yang; S J Yellin; C C Young; H Yuta; G H Zapalac; R W Zdarko; C Zeitlin; J Zhou

1994-01-01

118

Creation and uses of positron plasmas  

SciTech Connect

Advances in positron trapping techniques have led to room-temperature plasmas of 10[sup 7] positrons with lifetimes of 10[sup 3] s. Improvements in plasma manipulation and diagnostic methods make possible a variety of new experiments, including studies just being initiated of electron--positron plasmas. The large numbers of confined positrons have also opened up a new area of positron annihilation research, in which the annihilation cross sections for positrons with a variety of molecules have been measured, as well as the energy spread of the resulting gamma rays. Such measurements are of interest for fundamental physics and for the modeling of astrophysical plasmas.

Greaves, R.G.; Tinkle, M.D.; Surko, C.M. (Physics Department, University of California, San Diego, La Jolla, California 92093-0319 (United States))

1994-05-01

119

Spectral and lifetime domain measurements of rat brain tumours  

NASA Astrophysics Data System (ADS)

During glioblastoma surgery, delineation of the brain tumour margins remains difficult especially since infiltrated and normal tissues have the same visual appearance. This problematic constitutes our research interest. We developed a fibre-optical fluorescence probe for spectroscopic and time domain measurements. First measurements of endogenous tissue fluorescence were performed on fresh and fixed rat tumour brain slices. Spectral characteristics, fluorescence redox ratios and fluorescence lifetime measurements were analysed. Fluorescence information collected from both, lifetime and spectroscopic experiments, appeared promising for tumour tissue discrimination. Two photon measurements were performed on the same fixed tissue. Different wavelengths are used to acquire two-photon excitation-fluorescence of tumorous and healthy sites.

Abi Haidar, D.; Leh, B.; Allaoua, K.; Genoux, A.; Siebert, R.; Steffenhagen, M.; Peyrot, D.; Sandeau, N.; Vever-Bizet, C.; Bourg-Heckly, G.; Chebbi, I.; Collado-Hilly, M.

2012-02-01

120

Positron emission tomography, Borel measures and weak convergence  

Microsoft Academic Search

In this paper, we develop a refined version of the usual Poisson model for positron emission tomography (PET), in which the data space is finite dimensional, but the unknown emission intensity is represented by a Borel measure on the region of interest. We demonstrate that maximum likelihood (ML) estimators exist in the space of Borel measures and analyse an extension

B. A. Mair; Murali Rao; J. M. M. Anderson

1996-01-01

121

Measurement of the Lambdab0 Lifetime Using Semileptonic Decays  

Microsoft Academic Search

We report a measurement of the Lambdab0 lifetime using a sample corresponding to 1.3fb-1 of data collected by the D0 experiment in 2002 2006 during run II of the Fermilab Tevatron collider. The Lambdab0 baryon is reconstructed via the decay Lambdab0-->munu¯Lambdac+X. Using 4437±329 signal candidates, we measure the Lambdab0 lifetime to be tau(Lambdab0)=1.290-0.110+0.119(stat)-0.091+0.087(syst)ps, which is among the most precise measurements

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

2007-01-01

122

Measurement of the Tau Lepton Lifetime with BaBar  

SciTech Connect

The mean lifetime of the tau lepton is measured from the decay length distribution of 3-prong tau decays from e{sup +}e{sup -} collisions at the {Upsilon}(4S) resonance. A data sample of 80.0 fb{sup -1} collected with the BABAR detector at the PEP-II B Factory is used for this measurement. The measured tau lifetime is: {tau}{sub {tau}} = 289.40 {+-} 0.91 (stat.) {+-} 0.90 (syst.) fs. All the results are preliminary.

Lusiani, A.; /Pisa, Scuola Normale Superiore /INFN, Pisa

2005-06-27

123

Structure of Dipole Bands in 112In: Through Lifetime Measurement  

NASA Astrophysics Data System (ADS)

High-spin states of the 112In nucleus have been populated via 100Mo(16O, p3n) reaction at 80 MeV beam energy. Lifetimes of excited states of dipole bands have been measured using Doppler-shift attenuation method. The B(M1) transition rates deduced from the measured lifetimes show a rapid decrease with increasing angular momentum. The decrease in B(M1) values are well accounted by the prediction of tilted axis cranking calculations. These measurements confirm the presence of shears mechanism in this nuclei.

Trivedi, T.; Palit, R.; Sethi, J.; Saha, S.; Kumar, S.; Naik, Z.; Parkar, V. V.; Naidu, B. S.; Deo, A. Y.; Raghav, A.; Joshi, P. K.; Jain, H. C.; Sihotra, S.; Mehta, D.; Jain, A. K.; Choudhury, D.; Negi, D.; Roy, S.; Chattopadhyay, S.; Singh, A. K.; Singh, P.; Biswas, D. C.; Bhowmik, R. K.; Muralithar, S.; Singh, R. P.; Kumar, R.; Rani, K.

2012-09-01

124

A measurement of Rb using a lifetime-mass tag  

NASA Astrophysics Data System (ADS)

ALEPH's published measurement of Rb = ?(Z -> bb)/?(Z -> hadrons) using a lifetime tag is updated using the full LEP 1 data sample. Considerable effort has been devoted to understanding systematic effects. Charm background is better controlled by combining the lifetime tag with a tag based on the b/c hadron mass difference. Furthermore, the algorithm used to reconstruct the event primary vertex is designed so as to reduce correlations between the two hemispheres of an event. The value of Rb is measured to be 0.2167 +/- 0.0011 (stat) +/- 0.0013 (syst).

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

1997-02-01

125

Measurements of Metastable Lifetimes of Highly-Charged Ions  

NASA Astrophysics Data System (ADS)

Measurements have been made of the lifetimes and f -values of metastable levels of singly- and highly-charged positive ions (HCI). These contribute to the optical absorption, emission and energy balance in the ISM, stellar and solar atmospheres, etc. These ions and charge states are important for interpretations of data obtained from HST, EUVE, FUSE, Chandra and Newton missions. The vast majority of the millions of transition probabilities are presently being calculated by theory. However, the use of theory alone, unchecked by experimental verification, can lead to orders of magnitude error in the calculated electron densities and temperatures determined from diagnostic line ratios. The experimental lifetime measurements are carried out using the 14.0 GHz electron cyclotron ion source at the JPL facility. [1,2] The ECR ion source provides microampere current of ions such as O(1-6)+ and Mg(1-6)+. Ions are injected into a Kingdon ion trap and stored for times longer than the metastable lifetimes. Decay channels include intercombination, E2, M1 and 2E transitions. The UV photons are filtered by an interference filter and detected by a UV grade photomultiplier tube using a UV grade optical system. For wavelengths less than 180 nm, a cesium-iodide coated microchannel plate enhanced for UV performance is used. The Kingdon trap was constructed in collaboration with Texas A & M University. [3] Base vacuum is 4 x 10-10 Torr, hence quenching corrections are negligible. We have previously reported [1] lifetimes for the 2Po-4P intercombination transitions of C+ and have recently presented lifetime measurements of the 1S0 M1 transition of O2+ at 232 nm. [4] The measured lifetime of 541 ± 40 ms is in good agreement with previous measurements and a number of theoretical calculations. Additional metastable lifetimes have been measured and will be presented for Mg+6 , Fe9+, Fe10+ and Fe13+ metastable states. Additional lifetime measurements are planned for SIII, Ne V, Fe II and Fe XIII This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, and was supported by the National Aeronautics and Space Administration.

Smith, Steven J.; Chutjian, A.; Lozano, J.

2002-11-01

126

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

127

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

128

Lifetime measurements in neutral and singly ionized vanadium  

SciTech Connect

Radiative lifetimes of ten odd-parity levels of V I belonging to the 3d{sup 3}4s4p and 3d{sup 4}4p configurations and of 11 odd-parity levels of V II belonging to the 3d{sup 3}4p configuration are reported. The lifetimes were measured with use of single-step excitation and time-resolved fluorescence spectroscopy. The neutral and singly ionized vanadium atoms were produced in a laser-induced vanadium plasma.

Xu Huailiang; Jiang Zhankui; Lundberg, Hans [Department of Physics, Jilin University, Changchun 130023, China, Department of Physics, Lund Institute of Technology, S-221 00 Lund, Sweden, and Department of Physics, Laval University, Quebec, QC, G1K 7P4 (Canada); Department of Physics, Jilin University, Changchun 130023, China, and Department of Physics, Yantai University, Yantai, 264005 (China); Department of Physics, Lund Institute of Technology, S-221 00 Lund (Sweden)

2006-12-15

129

Low-spin lifetime measurements in {sup 74}Kr  

SciTech Connect

The nucleus {sup 74}Kr has been populated in the {sup 40}Ca({sup 40}Ca,2p{alpha}){sup 74}Kr fusion-evaporation reaction at a beam energy of 165 MeV and studied using the Gammasphere and Microball multidetector arrays. The lifetimes for low-spin states in the ground-state and two signature-split negative-parity bands were determined using the Doppler-shift attenuation method. These results are discussed together with the lifetimes measured for the high-spin states of these bands and compared with theoretical calculations.

Valiente-Dobon, J. J. [INFN Laboratori Nazionale di Legnaro, Legnaro (Italy); Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Svensson, C. E.; Grinyer, G. F.; Hyland, B.; Phillips, A. A.; Schumaker, M. A. [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Afanasjev, A. V. [Department of Physics and Astronomy, Mississippi State University, Mississippi 39762 (United States); Ragnarsson, I. [Lund Institute of Technology, P. O. Box 118 S-221 00 Lund (Sweden); Andreoiu, C. [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 3BX (United Kingdom); Appelbe, D. E. [CLRC Daresbury Laboratory, Daresbury, Warrington WA4 4AD (United Kingdom); Austin, R. A. E.; Cameron, J. A.; Waddington, J. C. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4K1 (Canada); Ball, G. C.; Hodgson, D. F.; Smith, M. B. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (Canada); Carpenter, M. P.; Moore, F.; Mukherjee, G.; Seweryniak, D. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] (and others)

2008-02-15

130

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

131

Polarization measurement of stored electron beam using Touschek lifetime  

NASA Astrophysics Data System (ADS)

Touschek lifetime of an electron beam in a storage ring depends on the beam polarization through the intrabeam scattering effect. Therefore, the electron beam polarization can be determined from the Touschek lifetime measurement. In this paper, we report on a systematic experimental procedure we developed to study the radiative polarization of a stored electron beam. Using this technique, we successfully observed the radiative polarization 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, C.; Zhang, J.; Li, J.; Wu, W. Z.; Mikhailov, S. F.; Popov, V. G.; Xu, H. L.; Chao, A. W.; Wu, Y. K.

2010-03-01

132

Lifetime measurements and decay of superdeformed bands in Hg isotopes  

Microsoft Academic Search

The lifetimes of states in Superdeformed (SD) bands in 192,194Hg have been measured using the Doppler shift attenuation method. Intrinsic quadrupole moments have been extracted for band 1 of 192Hg and for bands 1, 2, and 3 of 194Hg. It was found that the quadrupole moments for the \\

E. F. Moore; M. P. Carpenter; R. V. F. Janssens; T. L. Khoo; T. Lauritsen; D. Ackermann; I. Ahmad; H. Amro; D. Blumenthal; S. Fischer; G. Hackman; D. Nisius; F. Hannachi; A. Lopez-Martens; S. J. Asztalos; R. M. Clark; M. A. Deleplanque; R. M. Diamond; P. Fallon; R. Krueken; I.-Y. Lee; A. O. Macciavelli; F. S. Stephens; J. A. Becker; L. Bernstein; L. P. Farris; E. A. Henry; A. Korichi

1997-01-01

133

Measurement of masses and lifetimes of B hadrons  

SciTech Connect

We present recent measurements by the CDF and D{O} Collaborations at the Tevatron Collider on the masses and lifetimes of B hadrons. The results are compared to predictions based on Heavy Quark Effective Theory, lattice gauge theory, and quark models.

Filthaut, F.; /Nijmegen U.

2007-05-01

134

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

135

Measuring the Neutron Lifetime Using Magnetically Trapped Ultracold Neutrons  

Microsoft Academic Search

The neutron lifetime is an important parameter for tests of standard model and big bang nucleosynthesis. Our collaboration has successfully demonstrated the feasibility of using magnetically trapped ultracold neutrons for this measurement. In this experiment ultracold neutrons are loaded into an Ioffe-type superconducting magnetic trap as they are produced through the superthermal technique in superfluid helium-3. Trapped neutrons are then

Christopher O'Shaughnessy; Kevin Coakley; John Doyle; Robert Golub; Paul Huffman; Ekaterina Korobkina; Steve Lamoreaux; Hans Mumm; Karl Schelhammer; Pil-Neo Seo; Christopher Swank; Alan Thompson; Grace Yang; Liang Yang

2007-01-01

136

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

137

Measurement of the neutron lifetime by counting trapped protons  

SciTech Connect

The neutron lifetime {tau}{sub {ital n}} has been measured by counting decay protons stored in a Penning trap whose magnetic axis coincided with a neutron-beam axis. The result of the measurement is {tau}{sub {ital n}}=893.6{plus minus}5.3 s, which agrees well with the value predicted by precise measurements of the {beta}-decay asymmetry parameter {ital A} and the standard model.

Byrne, J.; Dawber, P.G.; Spain, J.A.; Williams, A.P. (University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom)); Dewey, M.S.; Gilliam, D.M.; Greene, G.L.; Lamaze, G.P. (National Institute of Standards and Technology, Gaithersburg, MD (USA)); Scott, R.D. (Scottish Universities Research and Reactor Center, East Kilbride, Glasgow G75 0QU (United Kingdom)); Pauwels, J.; Eykens, R.; Lamberty, A. (Commission of the European Communities, Joint Research Center, Central Bureau for Nuclear Measurements, B-2440 Geel (Belgium))

1990-07-16

138

Investigations on exponential lifetime measurements for fluorescence thermometry  

NASA Astrophysics Data System (ADS)

Lifetime-based methods have been, on the whole, one of the most successful schemes for fiber optic temperature sensing, using fluorescent materials whose response is intensity independent. Several approaches for determining the fluorescence lifetime, and with that the measurand, have been investigated. An experimental comparison of direct and indirect measurement methods, i.e., involving actual signals from representative optical media instead of simply using Monte Carlo simulations, has been carried out. Direct fitting methods, including Marquardt, log-fit and Prony, were used to estimate the fluorescence lifetime of a Cr3+:YAG-based sensor system and the results were compared. An agreement to better than 0.5% between Marquardt and log-fit algorithms and an agreement of about 1.5% between Marquardt and Prony approaches was found. Thus, a temperature reproducibility, of 0.5 and 1.2 °C, respectively, can be obtained with the Cr3+:YAG sensor system. An indirect measurement approach based on a phase-locked (analog-to-digital signal processor) (A-DSP) was also tested. It was found that when the A-DSP output is used to estimate the lifetime, it performs only slightly better than using direct fitting methods. On the contrary, when the whole A-DSP sensor system was directly calibrated against temperature, the measurement accuracy improves by at least a factor of 10.

Fernicola, V. C.; Rosso, L.; Galleano, R.; Sun, T.; Zhang, Z. Y.; Grattan, K. T. V.

2000-07-01

139

Defects in virgin and N+ -implanted ZnO single crystals studied by positron annihilation, Hall effect, and deep-level transient spectroscopy  

Microsoft Academic Search

High-quality single crystals of ZnO in the as-grown and N+ ion-implanted states have been investigated using a combination of three experimental techniques---namely, positron lifetime\\/slow positron implantation spectroscopy accompanied by theoretical calculations of the positron lifetime for selected defects, temperature-dependent Hall (TDH) measurements, and deep level transient spectroscopy (DLTS). The positron lifetime in bulk ZnO is measured to be (151±2)ps and

G. Brauer; W. Anwand; W. Skorupa; J. Kuriplach; O. Melikhova; C. Moisson; H. von Wenckstern; H. Schmidt; M. Lorenz; M. Grundmann

2006-01-01

140

Using a Mode-Locked Laser for Atomic Lifetime Measurements  

Microsoft Academic Search

We present a new technique for measuring atomic lifetimes, in which a single pulse from a mode-locked Ti:Sapphire laser excites atoms in a thermal beam to an excited state. A subsequent laser pulse is frequency-doubled and used to ionize any atoms remaining in the excited state, which are collected using a charged particle detector. The measurement is repeated using excitation

B. M. Patterson; G. Brooke; T. Takekoshi; R. J. Knize

2003-01-01

141

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

142

Reinforcement Mechanism Of Polyurethane-Urea/Clay Nanocomposites Probed By Positron Annihilation Lifetime Spectroscopy And Dynamic Mechanical Analysis  

SciTech Connect

A basis for quantitative analysis of the reinforcement mechanism of polyurethane-urea/clay nanocomposites using two characterization methods, positron annihilation life time spectroscopy (PALS) and dynamic mechanical analysis (DMA) is provided. DMA was used to measure the constrained volume fraction of amorphous soft segments induced by nanoclay and the storage modulus of the nanocomposites. The interfacial interactions in the nanocomposites were investigated by PALS. The modulus enhancement of the organoclay nanocomposites was found to have a good correlation with the volume fraction of the constrained region and the interfacial interactions.

Rath, S. K.; Patri, M. [Naval Materials Research Laboratory, Shil-Badlapur Road, Ambernath 421506, Maharastra (India); Sudarshan, K.; Pujari, P. K. [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai-400085 (India); Khakhar, D. V. [Department of Chemical Engineering, Indian Institute of Technology, Powai-76 (India)

2010-12-01

143

Microwave irradiation induced modifications on the interfaces in SAN/EVA/PVC and PVAc/BPA/PVP ternary polymer blends: Positron lifetime study  

NASA Astrophysics Data System (ADS)

Ternary polymer blends of poly(styrene-co-acrylonitrile)/poly(ethylene-co-vinylacetate)/poly(vinyl chloride) (SAN/EVA/PVC) and poly(vinyl acetate)/bisphenol A/polyvinylpyrrolidone (PVAc/BPA/PVP) with different compositions have been prepared by solvent casting method and characterized by positron lifetime spectroscopy and differential scanning calorimetry DSC. Phase modifications have been induced by irradiating the blends with microwave radiation. These changes have been monitored by measuring the free-volume content in the blends. The results clearly show improved interactions between the constituent polymers of the blends upon microwave irradiation. However, the free-volume data and DSC measurements are found to be inadequate to reveal the changes at the interfaces and the interfaces determine the final properties of the blend. For this we have used hydrodynamic interaction (?ij) approach developed by us to measure strength of hydrodynamic interaction at the interfaces. These results show that microwave irradiation stabilizes the interfaces if the blend contains strong polar groups. SAN/EVA/PVC blend shows an increased effective hydrodynamic interaction from ?3.18 to ?4.85 at composition 50/35/15 upon microwave irradiation and PVAc/BPA/PVP blend shows an increased effective hydrodynamic interaction from ?3.81 to ?7.57 at composition 20/50/30 after irradiation.

Dinesh, Meghala; Chikkakuntappa, Ranganathaiah

2013-09-01

144

Direct measurement of the parapositronium lifetime in alpha-SiO2.  

PubMed

The mean lifetime of delocalized parapositronium in alpha-SiO2 has been determined directly for the first time using a newly developed positron lifetime spectrometer based on BaF2 scintillators and a fast digital oscilloscope. The lifetime is found to be 156+/-4 ps, which is much longer than its intrinsic lifetime of 125 ps. This indicates clearly that the primary many-body effect on positronium in alpha-SiO2 is the screening of the Coulomb interaction between the constituent particles by electrons of the medium and that the average distance between the electron and positron in positronium becomes larger than its vacuum value. PMID:12785944

Saito, Haruo; Hyodo, Toshio

2003-05-13

145

Effect of free volume and temperature on the structural relaxation in polymethylphenylsiloxane: A positron lifetime and pressure-volume-temperature study  

Microsoft Academic Search

The microstructure of the free volume and its temperature dependence in polymethylphenylsiloxane (PMPS) have been examined using positron annihilation lifetime spectroscopy (PALS) and pressure-volume-temperature experiments. The hole-free volume fraction h and the specific hole-free and occupied volumes, Vf=hV and Vocc=(1-h)V, were estimated employing the Simha-Somcynsky (SS) lattice-hole theory. From the PALS spectra analyzed with the new routine LT9.0 the hole

G. Dlubek; M. Q. Shaikh; R. Krause-Rehberg; M. Paluch

2007-01-01

146

Measurements of cross sections for positrons scattered by Cs atoms^*  

NASA Astrophysics Data System (ADS)

We report our most recent measurements of total and positronium (Ps) formation cross sections (Q_Ps's) for positrons scattered by Cs atoms. These results are found to be in reasonable agreement with the theoretical calculations by Kernoghan et al.^1 The total cross sections and the upper limit on the Q_Ps's are measured using a beam transmission technique. The lower limit on the Q_Ps's and an additional contribution from ortho-Ps decay are measured by detecting two coincident ? rays in different energy windows. We are also making first estimates of Cs excitation cross sections. These results are obtained from the analysis of the energy spectrum of positrons that have passed through the scattering region. We resolve the fraction of positrons that have lost energy due to the excitation of Cs atoms. ^*Research supported by NSF Grant PHY 99-88093. ^1 A.A. Kernoghan, M.T. McAlinden, H.R.J. Walters, J. Phys. B 29, 3971 (1996).

Surdutovich, E.; Kauppila, W. E.; Miller, E. G.; Price, K. A.; Stein, T. S.

2004-05-01

147

Measurement of the average lifetime of hadrons containing bottom quarks  

SciTech Connect

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/sup +/e/sup -/ 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 Cherenkov counter assisted by a lead/scintillator electromagnetic shower counter. The lifetime measured is 1.17 psec, 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 V/sub cb/ element of the Kobayashi-Maskawa matrix to the range 0.042 (+0.005 or -0.004 (stat.), +0.004 or -0.002 (sys.)), where the errors reflect the uncertainty on tau/sub b/ only and not the uncertainties in the calculations which relate the b-lifetime and the element of the Kobayashi-Maskawa matrix.

Klem, D.E.

1986-06-01

148

Lifetime Measurements of Tagged Exotic- and Unbound Nuclear States  

NASA Astrophysics Data System (ADS)

A new Differential Plunger device for measuring pico-second lifetimes of Unbound Nuclear States (DPUNS) is being built at The University of Manchester. DPUNS has been designed to work with alpha-, beta- and isomer-tagging methods using the existing JUROGAM II--RITU--GREAT infrastructure at the University of Jyvaskyla, Finland. The importance of proton emission from nuclei is that it provides valuable nuclear-structure information as direct input to nuclear models beyond the drip line. New experimental data beyond the drip line can provide new extensions to these models especially with the possible coupling of weakly bound and unbound states to the continuum. The results of the first experiments to measure lifetimes of unbound nuclear states with this method was discussed along with possible future experiments which can be addressed with DPUNS using proton-, isomer- and alpha-tagging.

Cullen, D. M.

2011-11-01

149

Improved measurement of the B 0 and B + meson lifetimes  

NASA Astrophysics Data System (ADS)

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*- orbar D^0 meson. The second method used fully reconstructed B 0 and B + mesons. The third method, used to measure the B 0 lifetime, employed a partial reconstruction technique to identify B 0? D*- ? + X decays. The combined results are begin{gathered} tau _0 = 1.55 ± 0.06 ± 0.03 ps, \\ tau _ + = 1.58 ± 0.09 ± 0.03 ps, \\ tfrac{{tau _ + }}{{tau _0 }} = 1.03 ± 0.08 ± 0.02. \\ .

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

1996-03-01

150

An improved measurement of the B S 0 lifetime  

Microsoft Academic Search

This letter presents an updated measurement of the lifetime of the Bs0 meson using 3.6 million hadronic Z0 decays recorded by the OPAL detector at LEP from 1990 to 1994. A sample of Bs0 decays is obtained using Ds??+ combinations, where the Ds? is reconstructed in either the ??? or K?0K? decay mode. From 79 ± 13 Dx? combinations attributed

R J Akers; Gideon Alexander; J. Allison; K A Ametewee; K. J. Anderson; S. Arcelli; D A Axen; Georges Azuelos; A. H. Ball; E. Barberio; R. J. Barlow; R. Bartoldus; J Richard Batley; G. Beaudoin; A. Beck; G. A. Bekc; C. Beeston; T. Behnke; K. W. Bell; G. Bella; Stanislaus Cornelius Maria Bentvelsen; P. Berlich; Siegfried Bethke; O. Biebel; Ian J Bloodworth; P. Bock; H. M. Bosch; M. Boutemeur; S. Braibant; P G Bright-Thomas; R. M. Brown; A. Buijs; Helfried J Burckhart; R. Bürgin; C. Burgard; N. Capdevielle; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; C. Charlesworth; D. G. Charlton; S. L. Chu; P. E. L. Clarke; J. C. Clayton; S. G. Clowes; I. Cohen; J. E. Conboy; O. C. Cooke; M. Cuffiani; S. Dado; C. Dallapiccola; G. M. Dallavalle; C L Darling; S. De Jong; L. A. del Pozo; H. Deng; Michael Dittmar; M. S. Dixit; E. do Couto e Silva; J. E. Duboscq; E. Duchovni; G. Duckeck; I. P. Duerdoth; U. C. Dunwoody; J. E. G. Edwards; P. A. Elcombe; P. G. Estabrooks; E. Etzion; H. G. Evans; Franco Luigi Fabbri; B. Fabbro; M. Fanti; P. Fath; M. Fierro; Margret Fincke-Keeler; H. M. Fischer; P. Fischer; R. Folman; D. G. Fong; M. Foucher; H. Fukui; A. Fürtjes; P. Gagnon; A. Gaidot; J. W. Gary; J. Gascon; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; T. Geralis; G. Giacomelli; P. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; James D Gillies; J. Goldberg; D. M. Gingrich; M. J. Goodrick; W. Gorn; C. Grandi; E. Gross; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. A. Hart; M. Hauschild; C. M. Hawkes; E. Heflin; Richard J Hemingway; G. Herten; R. D. Heuer; J. C. Hill; S. J. Hillier; T. Hilse; P. R. Hobson; D. Hochman; R James Homer; A. K. Honma; R. Howard; R. E. Hughes-Jones; P. Igo-Kemenes; D. C. Imrie; A. Jawahery; P. W. Jeffreys; H. Jeremie; Martin Paul Jimack; M. Jones; R. W. L. Jones; P. Jovanovic; C. Jui; D A Karlen; J I Kanzaki; K. Kawagoe; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; B J King; J. King; J. Kirk; S. Kluth; T. Kobayashi; M. Kobel; D. S. Koetke; T. P. Kokott; S. Komamiya; R V Kowalewski; T. Kress; P. Krieger; J. von Krogh; P. Kyberd; G. D. Lafferty; H. Lafoux; R. Lahmann; W. P. Lai; J. Lauber; J. G. Layter; P. Leblanc; A. M. Lee; E. Lefebvre; Daniel Lellouch; C. Leroy; J. Letts; L. Levinson; S. L. Lloyd; F. K. Loebinger; G. D. Long; B. Lorazo; Michael J Losty; X. C. Lou; J. Ludwig; A. Luig; M. Mannelli; S. Marcellini; C. Markus; A. J. Martin; J. P. Martin; T. Mashimo; W. Matthews; P. Mättig; U. Maur; J A McKenna; T. J. McMahon; A. I. McNab; F. Meijers; F. S. Merritt; H. Mes; Aldo Michelini; R. P. Middleton; G. Mikenberg; D. J. Miller; R. Mir; W. Mohr; A. Montanari; T. Mori; M. Morii; U. Müller; B. Nellen; B. Nijjhar; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Orgen; N. J. Oldershaw; C. J. Oram; M. J. Oreglia; S. Orito; F. Palmonari; J. P. Pansart; G. N. Patrick; M. J. Pearce; P. D. Phillips; J. E. Pilcher; J L Pinfold; D. E. Plane; P R Poffenberger; B. Poli; A. Posthaus; T. W. Pritchard; H. Przysiezniak; M. W. Redmond; D. L. Rees; D. Rigby; M. G. Rison; S. A. Robins; D. Robinson; N L Rodning; J. M. Roney; E. Ros; A. M. Rossi; M. Rosvick; P. Routenburg; Y. Rozen; K. Runge; O. Runolfsson; D. R. Rust; M. Sasaki; C. Sbarra; A. D. Schaile; O. Schaile; F. Scharf; P. Scharff-Hansen; P. Schenk; B. Schmitt; M. Schröder; H. C. Schultz-Coulon; P. Schütz; M. Schulz; C. Schwick; J. Schwiening; W. G. Scott; M. Settles; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; G. P. Siroli; A. Skillman; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; Randall J Sobie; S. Söldner-Rembold; R. W. Springer; M. Sproston; A. Stahl; M. Starks; C. Stegmann; K. Stephens; J. Steuerer; B. Stockhausen; D. Strom; P. Szymanski; R. Tafirout; H. Takeda; T. Takeshita; P. Taras; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; M. A. Thomson; O. Tousignant; S. Towers; M. Tscheulin; T. Tsukamoto; A. S. Turcot; M. F. Turner-Watson; P. Utzat; R. Van Kooten; G. Vasseur; P. Vikas; M G Vincter; A. Wagner; D. L. Wagner; C. P. Ward; D. R. Ward; J. J. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; P. Weber; P. S. Wells; N. Wermes; B. Wilkens; G. W. Wilson; J. A. Wilson; V. H. Winterer; T. Wlodek; G. Wolf; S A Wotton; T. R. Wyatt; A. Yeaman; G. Yekutieli; M. Yurko; V. Zacek; W. Zeuner; G. T. Zorn

1995-01-01

151

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

152

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

153

Measurements of the B s 0 and ? b 0 lifetimes  

Microsoft Academic Search

This paper presents updated measurements of the lifetimes of the Bs0 meson and the ?b0 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??+ combinations, where the Ds? is fully reconstructed in the ???, 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

154

Measurement of the average lifetime of B hadrons at SLD  

Microsoft Academic Search

The authors present preliminary measurements of the average B hadron lifetime using a sample of 50,000 Z(sup 0) events collected by SLD at the SLC in 1993. Their first technique uses the impact parameter of tracks in jets opposite tagged b jets. They obtain (tau)(sub B)(Sigma (delta)) = 1.617 (+\\/-) 0.048 (+\\/-) 0.086 ps, and (tau)(sub B)((Sigma)(delta)) = 1.627 (+\\/-)

Greg Punkar; K Abe; I Abt; T Akagi; William W Ash; D Aston; N Bacchetta; K G Baird; C Baltay; H R Band; M B Barakat; G J Baranko; O Bardon; Timothy L Barklow; A O Bazarko; R Ben-David; Alberto C Benvenuti; T Bienz; 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 H 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 de Oliveira; C J S Damerell; S Dasu; R De Sangro; P De Simone; R Dell'Orso; M Dima; P Y C Du; R Dubois; B I Eisenstein; R Elia; D Falciai; C Fan; M J Fero; R Frey; K Furuno; T Gillman; G E Gladding; S González; G D Hallewell; E L Hart; Y Hasegawa; S J Hedges; S S Hertzbach; M D Hildreth; J Huber; M E Huffer; E W Hughes; H Hwang; Y Iwasaki; P Jacques; J A Jaros; A S Johnson; J R Johnson; R A Johnson; T R Junk; R Kajikawa; M S Kalelkar; I Karliner; H Kawahara; H W Kendall; 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 G S Leith; X Liu; M Loreti; A Lu; H L Lynch; J Ma; G Mancinelli; S L Manly; G C 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 Müller; T Nagamine; U Nauenberg; H A Neal; M Nussbaum; Y Ohnishi; L S Osborne; R S Panvini; T J Pavel; I Peruzzi; L Pescara; M Piccolo; L Piemontese; E Pieroni; K T Pitts; R J Plano; R Prepost; C Y Prescott; J Quigley; B N Ratcliff; T W Reeves; P E Rensing; L S Rochester; J E Rothberg; P C Rowson; J J Russell; O H Saxton; T L Schalk; R H Schindler; U Schneekloth; B A Schumm; A Seiden; S Sen; M H Shaevitz; J T Shank; G Shapiro; S L Shapiro; D J Sherden; N B Sinev; C Simopoulos; S R Smith; J A Snyder; M D Sokoloff; P E 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; A Yu Tolstykh; E Torrence; J Turk; T Usher; J Vavra; C Vannini; E N Vella; J P Venuti; P G Verdini; S R Wagner; A P Waite; S J Watts; A W Weidemann; 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; S J Yellin; C C Young; H Yuta; G H Zapalac; R W Zdarko; C Zeitlin; J Zhou

1994-01-01

155

SCATHA measurements of electron lifetimes at 5 < L < 8  

NASA Astrophysics Data System (ADS)

It is well known that the outer radiation belt is highly dynamic due to an imbalance between acceleration and loss processes, particularly during enhanced magnetic activity. Many loss mechanisms have been suggested since the beginning of space age, such as Coulomb collisions with atmospheric constituents, lightning generated whistler waves, man-made VLF transmitter signals, plasmaspheric hiss, chorus waves, electromagnetic ion cyclotron waves, and magnetopause shadowing. The electron lifetime is associated with loss processes, and is important in determination of pitch angle diffusion rates. Electron lifetimes have been studied by many satellites, such as SAMPEX, HEO, GOES, POLAR, Akebono, CRRES, SAC-C, DEMETER, and etc. We will reanalyze an old dataset from Spacecraft Charging AT High Altitudes (SCATHA) to determine the electron lifetime at 5 < L < 8. SCATHA was a NASA/Air Force satellite launched in early 1979 and the mission lasted approximately 10 year. It was placed in a near-synchronous, near-equatorial earth orbit with an inclination of 8.5 degree. The SC3 spectrometer measured the fluxes and pitch-angle distributions of the energetic electrons in the energy range 50 keV to 5 MeV. Although only a small fraction of data were fully analyzed, we take advantage of a relatively large dataset to systematically determine the decay timescales as function of L-shell, electron energy, and pitch angle during magnetically disturbed periods. Initial results indicate that the electron lifetime decrease with increasing L. In addition, the lifetime increases with increasing electron energy at L < 6.5, especially for low energy channels (0.06-0.45 MeV). We will also compare our results with previous publications.

Su, Y.; Ginet, G. P.; Starks, M. J.; O'Brien, T. P.; Roth, C. J.

2011-12-01

156

Fluorescence lifetime measurements of boronate derivatives to determine glucose concentration  

SciTech Connect

A novel investigation into the fluorescence lifetimes of molecules, both established and newly designed, was performed. These molecules are the basis of a continuous, minimally invasive, glucose sensor based on fluorescence lifetime measurements. This sensor, if coupled with an automated insulin delivery device, would effectively create an artificial pancreas allowing for the constant monitoring and control of glucose levels in a person with diabetes. The proposed sensor includes a fluorescent molecule that changes its' fluorescence properties upon binding selectively and reversibly to glucose. One possible sensor molecule is N-methyl-N-(9-methylene anthryl)-2-methylenephenylboronic acid (AB). The fluorescence intensity of AB was shown to change in response to changing glucose concentrations. (James, 1994) James proposed that when glucose binds to AB the fluorescence intensity increases due to an enhancement of the N{yields}B dative bond which prevents photoinduced electron transfer (PET). PET from the amine (N) to the fluorophore (anthracene) quenches the fluorescence. The dative bond between the boron and the amine can prevent PET by involving the lone pair of electrons on the amine in interactions with the boron rather than allowing them to be transferred to the fluorophore. Results of this research show the average fluorescence lifetime of AB also changes with glucose concentration. It is proposed that fluorescence is due to two components: (1) AB with an enhanced N{yields}B interaction, and no PET, and (2) AB with a weak N{yields}B interaction, resulting in fluorescence quenching by PET. Lifetime measurements of AB as a function of both the pH of the solvent and glucose concentration in the solution were made to characterize this two component system and investigate the nature of the N{yields}B bond. Measurements of molecules similar to AB were also performed in order to isolate behavior of specific AB constituents. These molecules are 9-(Methylaminomethyl)-anthracene (MAMA), and N-benzyl-N-methyl-N-methyl anthracene (AB-B). Fluorescence lifetime measurements confirmed the two species of AB, with and without PET. Fluorescence lifetimes were approximately 11 nsec without PET and 3 nsec with PET. The degree of the interaction between the N and the B atoms was also determined by fluorescence lifetime measurements. Electron transfer rates of AB were measured to be on the order of 10{sup 8} sec{sup -1}. Analysis of AB as a glucose sensor shows it has the potential for measuring glucose concentrations in solution with less than 5% error. Two novel glucose sensing molecules, Chloro-oxazone boronate (COB) and Napthyl-imide boronate (NIB), were synthesized. Both molecules have a N{yields}B dative bond similar to AB, but with longer wavelength fluorophores. COB and NIB were found to be unacceptable for use as glucose sensor molecules due to the small changes in average fluorescence lifetime.

Gable, J H

2000-06-01

157

Cosmic electron and positron spectra measured in 2002  

NASA Astrophysics Data System (ADS)

In August of 2002 we successfully carried out two balloon flights, extending our series of measurements of the time evolution of the spectra of cosmic ray electrons and positrons up to 2.5 GeV. Our positron detector, AESOP, flew for over 40 hours on a conventional balloon. On another flight, the electron detector LEE reached an altitude of 161,000 feet on a newly designed NASA balloon, which was the largest balloon ever successfully launched. Both flights, from Lynn Lake, Manitoba, were technically successful. We will report the preliminary analysis (now in progress) of the data from these flights in a continuation of our efforts to understand the origin of charge sign dependent effects in solar modulation.

Evenson, P.; Clem, J.

2003-04-01

158

Cosmic Electron and Positron Spectra Measured in 2002  

NASA Astrophysics Data System (ADS)

In August of 2002 we successfully carried out two balloon flights, extending our series of measurements of the time evolution of the spectra of cosmic ray electrons and positrons up to 2.5 GeV. Our positron detector, AESOP, flew for over 40 hours on a conventional balloon. On another flight, the electron detector LEE reached an altitude of 161,000 feet on a newly designed NASA balloon, which was the largest balloon ever successfully launched. Both flights, from Lynn Lake, Manitoba, were technically successful. We will report the preliminary analysis (now in progress) of the data from these flights in a continuation of our efforts to understand the origin of charge sign dependent effects in solar modulation. clem/aesoplee.html

Evenson, P.; Clem, J.

2002-12-01

159

Measurement of resolution and recovery in recent generation positron tomographs.  

PubMed

In positron tomographic images, the ability to differentiate closely lying structures, the spillover of activity from a region into adjacent regions and the reduction in apparent isotope concentration in small structures are all dependent on spatial resolution. Resolution in the reconstructed image is affected by (i) detector size, (ii) the spatial sampling used (e.g. stationary, wobble), (iii) the amount of smoothing in the reconstruction process (or subsequent to reconstruction) and (iv) the image pixel size. Under ideal conditions, modern commercial tomographs can produce a reconstructed spatial resolution of 5 mm or less. However, this is rarely realizable in a clinical study due to the inadequacy of counting statistics and the amplification of statistical noise. In practice, a smoother filter has to be used. This paper presents a summary of practical measurements of spatial resolution, and the related count recovery, performed on recent generation positron tomographs. It is intended to contribute to the definition of methods of measuring these parameters which is part of an on going concerted action in positron tomography supported by the European Commission. PMID:2583206

Spinks, T; Guzzardi, R; Bellina, C R

1989-01-01

160

New measurement of b-hadron lifetimes at CDF  

SciTech Connect

A measurement of b-hadron lifetimes in the fully reconstructed decay modes B{sup +} {yields} J/{Psi} K{sup +}, B{sup 0} {yields} J/{Psi} K*{sup 0}, B{sup 0} {yields} J/{Psi} K{sub s}{sup 0}, and {Lambda}{sub b}{sup 0} {yields} J/{Psi} {Lambda}{sup 0} is reported using data corresponding to an integrated luminosity of 4.3 fb{sup -1}, collected by the CDF II detector at the Fermilab Tevatron. The measured values are {tau}(B{sup +}) = 1.639 {+-} 0.009(stat) {+-} 0.009(syst) ps, {tau}(B{sup 0}) = 1.507 {+-} 0.010(stat) {+-} 0.008(syst) ps and {tau}({Lambda}{sub b}{sup 0}) = 1.537 {+-} 0.045(stat) {+-} 0.014(syst) ps. The lifetime ratios are {tau}(B{sup +})/{tau}(B{sup 0}) = 1.088 {+-} 0.009(stat) {+-} 0.004(syst) and {tau}({Lambda}{sub b}{sup 0})/{tau}(B{sup 0}) = 1.020 {+-} 0.030(stat) {+-} 0.008(syst). These are the most precise measurements of these lifetimes and ratios.

Fernandez, Juan Pablo; /Madrid, CIEMAT

2010-01-01

161

The direct measurement of the lifetime of the heavy ? hypernuclei  

NASA Astrophysics Data System (ADS)

The experiment E02-017 for direct measurement of the lifetime of heavy ? hypernuclei was carried out at Jefferson Lab Hall C in 2009. Fe, Cu, Ag, Au, Bi and U were employed as the target materials.The delayed fission from heavy hypernuclei produced by photon-nuclei reaction has been measured in this experiment.The only and recent COSY-13 result on the lifetime of heavy hypernuclei in the A range of 180-230 claimed to have the best accuracy but appeared quite controversial to the conclusion obtained from the studies of light hypernuclei. This work will provide observable lifetime in the high A range as an independant measurement to help further understanding on this issue. We have extracted the timing spectrum, the fitting strategy is under investigation. The data analysis status will be presented and the prelimilary result is expected in the near future which will either confirm or challenge the COSY-13 result, either way has significant impact in helping to fully understand the ?N->NN weak interaction and non-mesonic decay.

Qiu, Xiyu

2012-03-01

162

Lifetime measurements and shape coexistence in {sup 144}Dy  

SciTech Connect

The known level scheme of {sup 144}Dy has been extended and lifetime measurements have been made with the recoil-distance Doppler-shift method. Reduced transition probabilities and deformations have been determined for four low-lying transitions. These states form part of the first observed band crossing, giving information on the change in nuclear deformation resulting from the rearrangement of h{sub 11/2} protons in the nucleus. Two bands built upon excited 10{sup +} states have been assigned pi(h{sub 11/2}){sup 2} prolate and nu(h{sub 11/2}){sup -2} oblate configurations with tau=12(2)ps and 0.01lifetimes are reasoned to be a result of shape coexistence at low energy and moderate spin. A known four-quasiparticle dipole band has been extended to higher spin and lifetime measurements suggest a long-lived bandhead state. In this case, the excited states in the band may be consistent with a shears model interpretation of a magnetic dipole rotor. However, the measured B(M1)/B(E2) branching ratios reveal a larger than expected deformed rotational component compared with that in the analogous band in the lower mass isotone {sup 142}Gd.

Procter, M. G.; Cullen, D. M.; Niclasen, B.; Mason, P. J. R.; Rigby, S. V.; Dare, J. A.; Lumley, N. M. [Schuster Laboratory, University of Manchester, Manchester M13 9PL (United Kingdom); Scholey, C.; Greenlees, P. T.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nyman, M.; Puurunen, A.; Rahkila, P.; Ruotsalainen, P.; Saren, J. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland)

2010-05-15

163

Measurements of the Bs0 and ?b0 lifetimes  

NASA Astrophysics Data System (ADS)

This paper presents updated measurements of the lifetimes of the Bs0 meson and the ?b0 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 ??-, K*0K- and K-K0S decay channels and partially reconstructed in the ?l-?¯X decay mode. A sample of ?b0 decays is obtained using ?c+l- combinations, where the ?c+ is fully reconstructed in its decay to a pK-?+ final state and partially reconstructed in the ?l+?X decay channel. From 172+/-28 Ds-l+ combinations attributed to Bs0 decays, the measured lifetime is ?(Bs0)=1.50+0.16-0.15+/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129+/-25 ?c+l- combinations attributed to ?b0 decays, the measured lifetime is ?(?b0)=1.29+0.24- 0.22+/-0.06 ps, where the errors are statistical and systematic, respectively.

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

1998-04-01

164

Temperature dependence of positron annihilation characteristics on the surfaces of graphite powders  

Microsoft Academic Search

Positron lifetime measurements have been made on graphite powders, grafoils, and pyrolytic graphite crystals with different surface areas in the temperature range between 25° and 600 °C. Three positron lifetimes were found in these systems: a short-lived component (~0.2 ns) due to positrons in the bulk; a component (~0.45 ns) due to surface-trapped positrons; and a long-lived component (~2 ns)

Y. C. Jean; K. Venkateswaran; E. Parsai; K. L. Cheng

1984-01-01

165

Temperature dependence of positron annihilation characteristics on the surfaces of graphite powders  

Microsoft Academic Search

Positron lifetime measurements have been made on graphite powders, grafoils, and pyrolytic graphite crystals with different surface areas in the temperature range between 25° and 600 °C. Three positron lifetimes were found in these systems: a short-lived component (˜0.2 ns) due to positrons in the bulk; a component (˜0.45 ns) due to surface-trapped positrons; and a long-lived component (˜2 ns)

Y. C. Jean; K. Venkateswaran; E. Parsai; K. L. Cheng

1984-01-01

166

Lifetime Measurements and Coulomb Excitation of Light Hg Nuclei  

SciTech Connect

Two complementary experimental programs have taken place to investigate the origin and evolution of shape coexistence in the light mercury region. Recoil Distance Doppler-shift measurements were performed at the University of Jyvaeskylae utilizing the Koeln plunger device in conjunction with the JUROGAM+RITU+GREAT setup. In addition, Coulomb excitation measurements of {sup 184,186,188}Hg were performed at REX-ISOLDE using the MINIBALL Ge-detector array. The results of the lifetime measurements of the yrast states up to I{sup {pi}} = 10{sup +} in {sup 182}Hg are reported. Preliminary analysis of the Coulomb excitation data is also discussed.

Petts, A.; Butler, P. A.; Grahn, T.; Herzberg, R.-D.; Page, R. D.; Pakarinen, J.; Scheck, M. [Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool, L69 7ZE (United Kingdom); Blazhev, A.; Bruyneel, B.; Dewald, A.; Eberth, J.; Fransen, C.; Jolie, J.; Melon, B.; Pascovici, G.; Pissulla, Th.; Reiter, P.; Warr, N.; Weisshaar, D. [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); Bree, N. [Instituut voor Kern-en Stralingsfysica, Katholieke Universiteit Leuven, B-3001 Leuven (Belgium)] (and others)

2009-01-28

167

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

168

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

169

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

170

Energy migration alters the fluorescence lifetime of Cerulean: implications for fluorescence lifetime imaging Forster resonance energy transfer measurements.  

PubMed

Forster resonance energy transfer (FRET) is a physical phenomenon used to study molecular interactions in living cells. Changes in the fluorescence lifetime of proteins genetically tagged with a donor fluorophore, such as cyan fluorescent protein or Cerulean, are used to measure energy transfer to a protein tagged with an acceptor fluorophore (yellow fluorescent protein or Venus). Increased transfer efficiency is usually interpreted as closer proximity. Resonance energy transfer is also possible between identical fluorophores. This form of FRET is called energy migration resonance energy transfer (EM-RET). Theoretically, EM-RET should not alter the lifetime or emission spectrum measured from a population of fluorophores. We find a change in the fluorescent lifetime of Cerulean that correlates with energy migration and can result in significant errors when using Cerulean as a donor to measure FRET efficiencies based on fluorescence lifetimes [corrected] PMID:18601528

Koushik, Srinagesh V; Vogel, Steven S

171

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

172

Free volume in imidazolium triflimide ([C3MIM][NTf2]) ionic liquid from positron lifetime: amorphous, crystalline, and liquid states.  

PubMed

Positron annihilation lifetime spectroscopy (PALS) is used to study the ionic liquid 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)imide [C(3)MIM][NTf(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 Fürth's classical hole theory of liquids when taking into account Fürth'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 Å(3) at 150 K and 250 Å(3) at 265-300 K. From a comparison with the macroscopic volume, the hole density is estimated to be constant at 0.20×10(21) g(-1) corresponding to 0.30 nm(-3) at 265 K. The hole free volume fraction varies from 0.023 at 185 K to 0.073 at T(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 and standard deviation ?(3) of the o-Ps lifetime distribution and an increase in the o-Ps intensity I(3). The parameters of the second lifetime component and ?(2) behave parallel to the o-Ps parameters, which also shows the positron's (e(+)) 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(3) is attributed to the solvation of e(-) and e(+) particles. Different possible interpretations of the o-Ps lifetime in the crystalline state are briefly discussed. PMID:20886945

Dlubek, G; Yu, Yang; Krause-Rehberg, R; Beichel, W; Bulut, S; Pogodina, N; Krossing, I; Friedrich, Ch

2010-09-28

173

Laser spectroscopy and lifetime measurements on trapped francium  

NASA Astrophysics Data System (ADS)

This work describes the first experiments on laser cooled and trapped francium, the heavy alkali atom with no stable isotopes. We have created Fr in a nuclear fusion reaction at the Stony Brook LINAC and have confined a few thousand atoms in a volume of approximately 1 mm3. The cold atoms are an excellent source for laser spectroscopy. We have found the 8S1/2 and 9S1/2 energy levels and measured the hyperfine splitting of the 8S 1/2 level using two-step excitation. The 7S1/2 to 8S1/2 transition is promising for a future measurement of atomic parity nonconservation in this atom. We have performed the first Fr radiative lifetime measurements of the D 1 and D2 transitions using time-correlated single-photon counting. The lifetimes of the 7P3/2 and 7P1/2 levels are 21.02(11) ns and 29.45(11) ns respectively. The measurements are in excellent agreement with ab initio calculations. We have also observed a hyperfine anomaly in the splittings of the 7P1/2 level in a chain of isotopes, 208,209,210,211Fr.

Simsarian, John Edward

174

The lifetime of a beautiful and charming meson: B(c) meson lifetime measured using the D0 detector  

NASA Astrophysics Data System (ADS)

Using approximately 1.3 fb--1 of data collected by the DO detector between 2002 and 2006, the lifetime of the B+/-c meson is studied in the B+/-c ? J/psimu+/- + 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: t(B+/-c)=0. 448+0.038-0.036(stat)+/- 0.032(sys)ps.

Welty-Rieger, Leah

175

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

176

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

177

Comparison of Minority Carrier Lifetimes Measured by Photoconductive Decay and ac Photovoltaic Method  

Microsoft Academic Search

Minority carrier lifetimes measured by both ac photovoltaic and photoconductive decay methods are compared. The calculated results indicate that the maximum measurable lifetime for the ac photovoltaic method is about 7 times larger than that for the photoconductive decay method when surface recombination velocity is assumed to be infinite. The lifetimes for both p-type and n-type silicon rectangular samples measured

Noriaki Honma; Chusuke Munakata; Hirofumi Shimizu

1988-01-01

178

B(S) LIFETIME DIFFERENCE MEASUREMENTS FROM THE TEVATRON.  

SciTech Connect

The two collider experiments at the Tevatron, CDF and D0, have made a lot of progress in B{sub s} lifetime difference measurements. Here, they have included 3 different channels of measurements, namely, B{sub s} {yields} J/{psi} + {phi}, B{sub s} {yields} K{sup +}K{sup -} and B{sub s} {yields} D{sub s}{sup (*)+}D{sub s}{sup (*)-}. Combining all the available measurements, they have obtained {Delta}{Lambda}{sub s} = 0.097{sub -0.042}{sup +0.041} ps{sup -1} and {bar {tau}} = 1/{Lambda}{sub s} = 1.461 {+-} 0.030 ps. {Delta}{Lambda}{sub s} is now 2.3 {sigma} away from zero.

YIP, K.

2006-07-02

179

Lifetime measurements in the transitional nucleus 138Gd  

NASA Astrophysics Data System (ADS)

Lifetime measurements have been made in the ground-state band of the transitional nucleus 138Gd from coincidence recoil-distance Doppler-shift data. 138Gd nuclei were produced using the 106Cd (36Ar, 2p2n) reaction with a beam energy of 190 MeV. Reduced transition probabilities have been extracted from the lifetime data collected with the Köln plunger placed at the target position of the JUROGAM-II array. The B(E2) values have been compared with predictions from X(5) critical-point calculations, which describe the phase transition between vibrational and axially symmetric nuclear shapes, as well as with IBM-1 calculations at the critical point. While the excitation energies in 138Gd are consistent with X(5) predictions, the large uncertainties associated with the measured B(E2) values cannot preclude vibrational and rotational contributions to the low-lying structure of 138Gd. Although experimental knowledge for the low-lying ? and ?-vibrational bands in 138Gd is limited, potential-energy surface calculations suggest an increase in ? softness in the ground-state band. In order to more fully account for the effects of ? softness, the X(5) and IBM-1 calculations need to be extended to include the ? degree of freedom for 138Gd.

Procter, M. G.; Cullen, D. M.; Ruotsalainen, P.; Braunroth, T.; Dewald, A.; Fransen, C.; Grahn, T.; Greenlees, P. T.; Hackstein, M.; Hauschild, K.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Lopez-Martens, A.; Leino, M.; Litzinger, J.; Mason, P. J. R.; Nieminen, P.; Peura, P.; Rahkila, P.; Reed, M. W.; Rice, S.; Rinta-Antilla, S.; Rother, W.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Taylor, M. J.; Uusitalo, J.; Vitturi, A.; Shi, Y.; Xu, F. R.

2011-08-01

180

Lifetime measurements in the transitional nucleus {sup 138}Gd  

SciTech Connect

Lifetime measurements have been made in the ground-state band of the transitional nucleus {sup 138}Gd from coincidence recoil-distance Doppler-shift data. {sup 138}Gd nuclei were produced using the {sup 106}Cd ({sup 36}Ar, 2p2n) reaction with a beam energy of 190 MeV. Reduced transition probabilities have been extracted from the lifetime data collected with the Koeln plunger placed at the target position of the JUROGAM-II array. The B(E2) values have been compared with predictions from X(5) critical-point calculations, which describe the phase transition between vibrational and axially symmetric nuclear shapes, as well as with IBM-1 calculations at the critical point. While the excitation energies in {sup 138}Gd are consistent with X(5) predictions, the large uncertainties associated with the measured B(E2) values cannot preclude vibrational and rotational contributions to the low-lying structure of {sup 138}Gd. Although experimental knowledge for the low-lying {gamma} and {beta}-vibrational bands in {sup 138}Gd is limited, potential-energy surface calculations suggest an increase in {gamma} softness in the ground-state band. In order to more fully account for the effects of {gamma} softness, the X(5) and IBM-1 calculations need to be extended to include the {gamma} degree of freedom for {sup 138}Gd.

Procter, M. G.; Cullen, D. M.; Taylor, M. J. [Schuster Laboratory, University of Manchester, Manchester, M13 9PL (United Kingdom); Ruotsalainen, P.; Grahn, T.; Greenlees, P. T.; Hauschild, K.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Lopez-Martens, A.; Leino, M.; Nieminen, P.; Peura, P.; Rahkila, P.; Rinta-Antilla, S.; Sandzelius, M.; Saren, J. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland)

2011-08-15

181

Measurement of the B0 and B- meson lifetimes  

NASA Astrophysics Data System (ADS)

The lifetimes of the B0 and B- mesons are measured using a sample of about four million hadronic /Z decays collected from 1991 to 1995 with the Aleph detector at LEP. The data sample has been recently reprocessed, achieving a substantial improvement in the tracking performance. Semileptonic decays of B0 and B- mesons are partially reconstructed by identifying events containing a lepton with an associated D*+ or D0 meson. The proper time of the /B meson is estimated from the measured decay length and the momentum of the /D-lepton system. A fit to the proper time of 1880 D*+l- and 2856 D0l- candidates yields the following results: ?B^0=1.518+/-0.053+/-0.034 ps, ?B^-=1.648+/-0.049+/-0.035 ps, ?B^-/?B^0=1.085+/- 0.059+/-0.018.

Barate, R.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Merle, E.; Minard, M.-N.; Pietrzyk, B.; Bravo, S.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Graugés, E.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L. M.; Pacheco, A.; Ruiz, H.; Colaleo, A.; Creanza, D.; de Palma, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Boix, G.; Buchmüller, O.; Cattaneo, M.; Cerutti, F.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Greening, T. C.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Lehraus, I.; Mato, P.; Minten, A.; Moutoussi, A.; Ranjard, F.; Rolandi, L.; Schlatter, D.; Schmitt, M.; Schneider, O.; Spagnolo, P.; Tejessy, W.; Teubert, F.; Tournefier, E.; Wright, A. E.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J.-C.; Rougé, A.; Rumpf, M.; Swynghedauw, M.; Verderi, M.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Antonelli, A.; Antonelli, M.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Chiarella, V.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Halley, A. W.; Lynch, J. G.; Negus, P.; O'Shea, V.; Raine, C.; Teixeira-Dias, P.; Thompson, A. S.; Cavanaugh, R.; Dhamotharan, S.; Geweniger, C.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Marinelli, N.; Sedgbeer, J. K.; Thompson, J. C.; Thomson, E.; Ghete, V. M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Buck, P. G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W. L.; Robertson, N. A.; Giehl, I.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; Wachsmuth, H.; Zeitnitz, C.; Bonissent, A.; Carr, J.; Coyle, P.; Leroy, O.; Payre, P.; Rousseau, D.; Talby, M.; Aleppo, M.; Ragusa, F.; Dietl, H.; Ganis, G.; Heister, A.; Hüttmann, K.; Lütjens, G.; Mannert, C.; Männer, W.; Moser, H.-G.; Schael, S.; Settles, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Azzurri, P.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, P.; Jacholkowska, A.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Yuan, C.; Zerwas, D.; Bagliesi, G.; Boccali, T.; Calderini, G.; Ciulli, V.; Foà, L.; Giassi, A.; Ligabue, F.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sciabà, A.; Sguazzoni, G.; Tenchini, R.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Cowan, G.; Green, M. G.; Medcalf, T.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Clifft, R. W.; Edgecock, T. R.; Norton, P. R.; Tomalin, I. R.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M.-C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Konstantinidis, N.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Cartwright, S.; Combley, F.; Lehto, M.; Thompson, L. F.; Affholderbach, K.; Böhrer, A.; Brandt, S.; Grupen, C.; Misiejuk, A.; Prange, G.; Sieler, U.; Giannini, G.; Gobbo, B.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Cranmer, K.; Elmer, P.; Ferguson, D. P. S.; Gao, Y.; González, S.; Hayes, O. J.; Hu, H.; Jin, S.; Kile, J.; McNamara, P. A., III; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; Wu, S.; Wu, X.; Zobernig, G.

2000-01-01

182

Measuring the Neutron Lifetime using Magnetically Trapped Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

The neutron beta-decay lifetime is important in both theoretical predictions of the primordial abundance of ^4He and providing a strong unitarity test of the CKM mixing matrix. We have previously demonstrated trapping of Ultracold Neutrons (UCN) in a magnetic trap, and, though statistically limited, measured a lifetime consistent with the world average. A major upgrade of the apparatus has now been completed at NIST. In our unique approach, a 0.89 nm neutron beam is incident on a superfluid ^4He target within the minimum field region of an Ioffe-type magnetic trap. Neutrons are downscattered by single phonon scattering in liquid helium to near rest and trapped; at sufficiently low temperatures, the low phonon density in the helium suppresses upscatter. The electron accompanying neutron decay produces scintillation in the superfluid helium and can be detected in real time. Previous statistical limitations as well as systematics related to neutron material bottling will be reduced by significant increases in field strength and trap volume. Details of analyses of the systematics as well as the initial performance benchmarks of the new apparatus will be presented.

Mumm, H. P.; Coakley, K. J.; Dewey, M. S.; Huber, M. G.; Hughes, P. P.; Thompson, A. K.; Golub, R.; Huffer, C. R.; Huffman, P. R.; O'Shaughnessy, C. M.; Schelhammer, K. W.

2010-11-01

183

Ligament coarsening in nanoporous gold: Insights from positron annihilation study  

NASA Astrophysics Data System (ADS)

Positron lifetime experiments, coupled with scanning electron microscopy studies, have been used to follow the coarsening of the ligaments of nanoporous Au (np-Au), prepared by electrochemical dealloying of Ag75Au25. Positron lifetime measurements in the as-prepared np-Au indicate two lifetime components, identified with annihilation at vacancies within the ligaments and at the ligament-pore interface. The variation of these lifetime parameters with annealing temperature indicates distinct changes that correlate the migration of vacancies to the growth of ligaments. The lifetime component, corresponding to the annihilation at the ligament-pore interface, shows signature of ligament surface instability.

Viswanath, R. N.; Chirayath, V. A.; Rajaraman, R.; Amarendra, G.; Sundar, C. S.

2013-06-01

184

Free volume of an epoxy resin and its relation to structural relaxation: Evidence from positron lifetime and pressure-volume-temperature experiments  

NASA Astrophysics Data System (ADS)

The microstructure of the free volume and its temperature dependence in the epoxy resin diglycidyl ether of bisphenol-A (DGEBA) have been examined using positron annihilation lifetime spectroscopy (PALS, 80-350K , 10-5Pa ) and pressure-volume-temperature (PVT, 293-470K , 0.1-200MPa ) experiments. Employing the Simha-Somcynsky lattice-hole theory (S-S eos), the excess (hole) free volume fraction h and the specific free and occupied volumes, Vf=hV and Vocc=(1-h)V , were estimated. From the PALS spectra analyzed with the new routine LT9.0 the hole size distribution, its mean, ?vh? , and mean dispersion, ?h , were calculated. ?vh? varies from 35to130Å3 . From a comparison of ?vh? with V and Vf , the specific hole number Nh' was estimated to be independent of the temperature [Nh(300K)=Nh'/V=0.65nm-3] . From comparison with reported dielectric and viscosity measurements, we found that the structural relaxation slows down faster than the shrinkage of the hole free volume Vf would predict on the basis of the free volume theory. Our results indicate that the structural relaxation in DGEBA operates via the free-volume mechanism only when liquidlike clusters of cells of the S-S lattice appear which contain a local free volume of ˜1.5 or more empty S-S cells. The same conclusion follows from the pressure dependency of the structural relaxation and Vf . It is shown that PALS mirrors thermal volume fluctuations on a subnanometer scale via the dispersion in the ortho-positronium lifetimes. Using a fluctuation approach, the temperature dependency of the characteristic length of dynamic heterogeneity, ? , is estimated to vary from ?=1.9nm at Tg to 1.0nm at T/Tg>1.2 . A model was proposed which relates the spatial structure of the free volume as concluded from PALS to the known mobility pattern of the dynamic glass transition at low (cooperative ? -relaxation) and high ( a -relaxation) temperatures. We discuss possible reasons for the differences between the results of our method and the conclusion from dynamic heat capacity.

Dlubek, Günter; Hassan, E. M.; Krause-Rehberg, Reinhard; Pionteck, Jürgen

2006-03-01

185

Lifetime Measurements in 134Pr and Chirality in Nuclei  

NASA Astrophysics Data System (ADS)

Lifetimes of exited states in 134Pr were measured be means of the recoil distance Doppler-shift and Doppler-shift attenuation techniques. The experiments were performed at IReS, Strasbourg using the EUROBALL IV spectrometer, in conjunction with the inner BGO ball and the Cologne coincidence plunger apparatus. Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F, 4n)134Pr. Reduced transition probabilities in 134Pr are compared to the predictions of the two quasiparticle+triaxial rotor and interacting boson fermion-fermion models. The experimental results do not support the presence of static chirality in 134Pr underlying the importance of shape fluctuations. Only within a dynamical context the presence of intrinsic chirality in 134Pr can be supported.

Tonev, D.; Petkov, P.; Balabanski, D. L.; de Angelis, G.; Gadea, A.; Napoli, D. R.; Marginean, N.; Dewald, A.; Pejovic, P.; Fitzler, A.; Möller, O.; Zell, K. O.; Brant, S.; Frauendorf, S.; Bazzacco, D.; Lenzi, S.; Lunardi, S.; Bednarczyk, P.; Curien, D.; Petrache, C.; Zhong, Q.; Zhang, Y. H.; Zhang, Jing-Ye

186

Search for thermally generated monovacancies in silicon using monoenergetic positrons  

NASA Astrophysics Data System (ADS)

Using a monoenergetic, variable-energy positron beam, measurements of Doppler broadening and positronium fraction for positron-annihilation radiation from high-resistivity silicon have been made up to the melting point. The measurements show no clear evidence of positron trapping into thermally generated monovacancies which Dannefaer, Mascher, and Kerr observed by measuring the lifetimes of positrons emitted by an in situ source. A lower limit of about 3.6 eV is placed on the formation enthalpy of a neutral monovacancy, subject to assumptions about positron-trapping rate, binding energy, and monovacancy formation entropy.

Throwe, J.; Leung, T. C.; Nielsen, B.; Huomo, H.; Lynn, K. G.

1989-12-01

187

Measurements of cross-sections for positrons and electrons scattered by Cs atoms  

NASA Astrophysics Data System (ADS)

Total scattering cross-sections have been measured for 1-60 eV positrons and 6-200 eV electrons scattered by Cs atoms using a beam-transmission technique with a heated scattering cell. For 0.5-25 eV positron scattering we have measured both upper and lower limits on positronium formation cross-sections.

Surdutovich, E.; Kauppila, W. E.; Kwan, C. K.; Miller, E. G.; Parikh, S. P.; Price, K. A.; Stein, T. S.

2004-07-01

188

Carrier recombination lifetime measurement of bonded SOI wafers by microwave photoconductivity decay method  

Microsoft Academic Search

Microwave photoconductivity decay (?PCD) method was used for the measurement of bulk carrier recombination lifetime of bonded silicon-on-insulator (SOI) wafers in order to evaluate the quality of the starting material from different vendors and to monitor the degradation of lifetime during processing of the wafers. The goal of the investigation was to determine a correlation between the carrier lifetime of

S. Ahmed; B. Catarini; S. Lizotte; K. Iba; H. Hashizume; S. Sumie

1997-01-01

189

Atomic Oscillator Strengths by Emission Spectroscopy and Lifetime Measurements  

NASA Astrophysics Data System (ADS)

Over the last seven years, we have carried out numerous oscillator strength measurements for some light and medium heavy elements (Musielok et al. 1995, 1996, 1997, 1999, 2000; Veres & Wiese 1996; Griesmann et al. 1997; Bridges & Wiese 1998; Kling et al. 2001; Kling & Gries- mann 2000; Bridges & Wiese to be published). Most recently we have determined numerous transitions of Mu II (Kling et al. 2001; Kling & Griesmann 2000) and are now working on Cl I (Bridges & Wiese to be published). See the summary statement at the end of the text. For the emission measurements, we have applied either a high-current wall-stabilized arc (described for example, in Musielok et al. (1999)), or a high-current hollow cathode, or a Penning discharge. The latter two sources were used for branching ratio measurements from common upper 1ev- els, while the wall-stabilized arc was operated at atmospheric pressure under the condition of partial local thermodynamic equilibrium, which allows the measurement of relative transition probabilities. Absolute data were obtained by combining the emission results with lifetime data measured by other research groups, especially the University of Hannover, with which we have closely collaborated. This group uses the laser induced fluorescence (LIF) technique. Our emission spectra were recorded for the light elements with a 2 m grating spectrometer, or, for Mu II, with an FT 700 vacuum ultraviolet Fourier transform spectrometer. The radiometric calibration was carried out with a tungsten strip lamp for the visible part of the spectrum and with a deuterium lamp for the ultraviolet. All measurements were made under optically thin conditions, which was checked by doubling the path length with a focusing mirror setup. Typical uncertainties of the measured oscillator strengths are estimated to be in the range 15%-20% (one-standard deviation). However, discrepancies with advanced atomic structure theories are sometimes much larger. In Tables 1-3 and Fig. 1, we present some sample com- parisons, mainly with such advanced calculations.

Wiese, W. L.; Griesmann, U.; Kling, R.; Musielok, J.

2002-11-01

190

Evolution of the positron annihilation lifetime for ageing in {beta} phase Cu-Al-Ni-(Ti)-(Mn) shape memory alloys  

SciTech Connect

During the last years, the positron annihilation technique has proven to be a sensitive tool for the characterization of phase transitions, and in particular of the martensitic transformation in Cu-based alloys. The differences in structure between the high temperature phase (cubic) and the martensite (monoclinic) produce distinctive positron annihilation characteristics which allow the determination of the transformation temperature range. In the present article the influence of these parameters on the positron annihilation characteristics of three Cu-Al-Ni shape memory alloys is discussed. Two of the chosen compositions contain Ti and Mn, which have been added to the ternary Cu-Al-Ni alloy in order to improve its mechanical properties. The effect of those elements has also been evaluated.

Hurtado, I.; Van Humbeeck, J. [Katholieke Universiteit Leuven (Belgium). Dept. Metaalkunde en Toegepaste Materiaalkunde; Segers, D.; Dorikens-Vanpraet, L.; Dauwe, C. [Rijksuniversiteit Gent (Belgium). Vakgroep Subatomaire en Stralingsfysica

1995-09-01

191

Lifetime measurements of TSD bands in ^174Hf  

NASA Astrophysics Data System (ADS)

Four new bands in ^174Hf were identified in a previous experiment performed at ANL using GAMMASPHERE teM1. These bands exhibit large dynamic moments of inertia which indicate that the bands are strongly deformed. Ultimate Cranker calculations suggest that these new bands have significant triaxial deformation as well. A lifetime measurement was performed to determine the quadrupole moments of the new sequences at LBNL with GAMMASPHERE. The reaction ^130Te(^48Ca,4n) was used at a beam energy of 200 MeV. The recoils were stopped in a thick Au backing of the target. In the consequent sort, approximately 3.5 billion events were collected and stored into a BLUE teM2 database. The Doppler Shift Attenuation Method (DSAM) was performed by measuring the centroid shifts of the in-band TSD transitions in the forward and backward angles of GAMMASPHERE. Results from this analysis and a comparison with the predicted Ultimate Cranker calculations will be presented. This work is funded by the U. S. Department of Energy through contracts no. DE-FG02-96ER40983 (University of Tennessee) and W-31-109-ENG-38 (Argonne National Laboratory). 9 M1 M. K. Djongolov et al., Phys. Lett. B (submitted). M2 M. Cromaz et al., Nucl. Instrum. Methods Phys. Res. A 462, 519 (2001). thebibliography

Djongolov, M. K.; Hartley, D. J.; Riedinger, L. L.; Bingham, C. B.; Goon, J. Tm.; Park, H. I.; Janssens, R. V. F.; Kondev, F. G.; Moore, E. F.; Cromaz, M.; Fallon, P.; Macchiavelli, A. O.; Riley, M. A.; Campbell, D.

2003-04-01

192

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

Microsoft Academic Search

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

Hidetaka Takato; Isao Sakata; Ryuichi Shimokawa

2002-01-01

193

The cosmic-ray positron and electron spectra measured by PAMELA  

NASA Astrophysics Data System (ADS)

The 15^{th} of June 2006, the satellite-borne experiment PAMELA was launched from the Baikonur cosmodrome and, since then, it is continuously taking data. The apparatus is optimized for the study of the cosmic-ray antimatter component in order to measure accurately the antiproton and positron energy spectra to investigate the nature of dark matter; in addition to these it is revealing protons, electrons and light nuclei. Positrons and electrons are a small but not negligible component of the cosmic radiation. They provide information regarding the origin and propagation of cosmic rays in the Galaxy. A particle classification system for the imaging calorimeter with a multivariate approach was adopted to significantly improve the positron selection. We will reported new measurements of the cosmic-ray electron and positron spectra and of the positron fraction, extending previously published PAMELA measurements up to 200 GeV.

Bellotti, Roberto; Mocchiutti, Emiliano; Bianco, Andrea; Rossetto, Laura; Monaco, Alfonso

2012-07-01

194

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

195

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

196

High-K decays and lifetime measurements in 172Hf  

NASA Astrophysics Data System (ADS)

The known level scheme of 172Hf has been extended with three new collective rotational bands. Many new transitions have also been observed which link the known bands into the lower-spin states, thereby permitting unambiguous spin and parity assignments to be made for the first time. In particular seven low-intensity ?-ray transitions have been established which link the K=12 intrinsic state into a series of lower-K states. The half-life of the K=12 state has been determined to be less than 2 ns and reduced hindrance factors have been calculated for each of the new decay transitions. In apparent conflict with the K-selection rule, most of these new decays have small reduced hindrance factors. The reasons for this apparent breakdown in the K-selection rule are discussed in terms of a mixing between states of both low- and high-K. In addition the mean lifetimes of the states in four of the collective rotational bands have been determined using the Doppler shift attenuation method. The deformations extracted from these measurements are in good agreement with predictions from theoretical Total Routhian Surface calculations based on the proposed configuration assignments.

Cullen, D. M.; Reed, A. T.; Appelbe, D. E.; Wilson, A. N.; Paul, E. S.; Clark, R. M.; Fallon, P.; Lee, I. Y.; Macchiavelli, A. O.; MacLeod, R. W.

1998-08-01

197

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

198

Lifetime Based Temperature and Velocity Measurement using High-Speed Camera and Temperature Sensitive Particles  

Microsoft Academic Search

A simultaneous measurement technique of velocity and temperature distribution in a fluid flow was developed. Particle image velocimetry (PIV) was combined with a lifetime based scalar measurement technique. A measurement method based on the luminescent lifetime is appropriate for detecting the transient temperature field. Developed method needs a high speed camera, a laser (one excitation wave length) and temperature sensitive

Satoshi Someya; Mitsunori Uchida; Kaoru Tominaga; Keiko Ishii; Yanrong Li; Koji Okamoto

2009-01-01

199

Measurement of the Lifetime of the Bc± Meson in the Semileptonic Decay Channel  

Microsoft Academic Search

Using approximately 1.3fb-1 of data collected by the D0 detector between 2002 and 2006, we measure the lifetime of the Bc± meson in the Bc±-->J\\/psimu±+X final state. A simultaneous unbinned likelihood fit to the J\\/psi+mu 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.

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

2009-01-01

200

Positron annihilation study on ZnO-based scintillating glasses  

NASA Astrophysics Data System (ADS)

Positron lifetime of ZnO-based scintillating glasses (55 - x)SiO 2-45ZnO- xBaF 2 ( x = 5, 10, 15 mol%) were measured with a conventional fast-fast spectrometer. Three positron lifetime components ?1, ? 2, and ?3 are ˜0.23 ns, ˜0.45 ns, and ˜1.6 ns, respectively. All the three positron lifetime components first increase with increasing BaF 2 concentration from 5 mol% to 10 mol%, then decreases as BaF 2 further increases to 15 mol%. The result suggests that the glass sample with 10 mol% BaF 2 contains the highest defect density, and is in excellent agreement with glass chemistry, glass density, thermal properties, and calculated crystallinity. Therefore, positron annihilation lifetime measurement is an effective tool for analyzing defects in ZnO-based scintillating glasses.

Nie, Jiaxiang; Yu, Runsheng; Wang, Baoyi; Ou, Yuwen; Zhong, Yurong; Xia, Fang; Chen, Guorong

2009-04-01

201

Sensitive measurement of positron emitters eluted from HPLC.  

PubMed

For sensitive analysis of the radioactive-metabolite in human PET, a radio-HPLC system coupled to a newly designed positron detector was constructed. The detector had the advantages of low noise level (1.7 +/- 1.0 cpm) and high sensitivity (32 +/- 1%) due to coincidence counting and large BGO crystals. Furthermore, the detector was easy to move, since a pair of the BGO housings coupled to photomultipliers was effectively arranged in parallel and a HPLC cell with different volume could be inserted between the BGO housing. This radio-HPLC system was useful for analyzing samples with low radioactivity. It was applied to the measurement of [11C]FLB457 in plasma, having high affinity and high selectivity with dopamine D2 receptors. Extremely low radioactivity of [11C]FLB457 (2500 dpm) could be analyzed by using the radio-HPLC system. The performance of this detector was compared with those of commercially available systems that had been used as sensitive detectors for HPLC. PMID:11393764

Takei, M; Kida, T; Suzuki, K

2001-08-01

202

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

203

Positron annihilation and cluster formation in nitrogen fluid  

Microsoft Academic Search

The annihilation of positrons in nitrogen has been studied both experimentally and theoretically. Lifetime measurements over the temperature range 60 to 400 K and at pressures up to 80 bar show that below 300 K, clustering of nitrogen molecules occurs around the positron. Experimental data are compared to those in other gases. Results of density functional calculations are in very

K. Rytsola; K. Rantapuska; P. Hautojarvi

1984-01-01

204

Comparison of Minority Carrier Lifetimes Measured by Photoconductive Decay and ac Photovoltaic Method  

NASA Astrophysics Data System (ADS)

Minority carrier lifetimes measured by both ac photovoltaic and photoconductive decay methods are compared. The calculated results indicate that the maximum measurable lifetime for the ac photovoltaic method is about 7 times larger than that for the photoconductive decay method when surface recombination velocity is assumed to be infinite. The lifetimes for both p-type and n-type silicon rectangular samples measured by the ac photovoltaic method are in good agreement with the lifetimes ranging from 90 ?s to 1 ms measured by the photoconductive decay method standardized by the Japanese Industrial Standard Committee. However, lifetimes measured by a noncontact photoconductive decay method using microwaves are far shorter than those measured by the above two methods.

Honma, Noriaki; Munakata, Chusuke; Shimizu, Hirofumi

1988-08-01

205

Study of applicability of AC photovoltaic method and photoconductive decay method using microwaves as noncontact methods for bulk lifetime measurement  

Microsoft Academic Search

The applicability of the ac photovoltaic method and photoconductive decay method using microwaves (mu-PCD method) as bulk lifetime measurement methods were studied. Lifetimes measured by these two methods were compared with bulk lifetimes measured by the photoconductive decay method standardized by ASTM:F28-75. Lifetimes measured by the ac photovoltaic method were in good agreement with the bulk lifetimes of less than

Masato Toda; Yutaka Kitagawara; Takao Takenaka

1993-01-01

206

Carrier Lifetime Measurements by Microwave Photoconductive Decay Method at Low Injection Levels  

NASA Astrophysics Data System (ADS)

The minority carrier lifetime of Si wafers has been measured at very low injection levels by employing a newly developed microwave photoconductive decay (?-PCD) technique. It is found that the effective lifetime is dramatically increased for the case of p-type Si when the injection level is reduced to two orders of magnitude less than the equilibrium value. In contrast to this, the n-type wafer lifetime remains almost un-changed even upon lowering the injection level. Also, it is shown that the different contamination levels of Fe in Si wafers are clearly discriminated by the measured lifetime.

Fujihira, Chiyo; Morin, Michel; Hashizume, Hidehisa; Friedt, Jean; Nakai, Yasuhide; Hirose, Masataka

1993-09-01

207

First lifetime measurement of dipole collective bands in neutron-deficient lead nuclei  

Microsoft Academic Search

Lifetimes of states in two DeltaI=1 bands in 198Pb have been measured using the Doppler-shift attenuation method. The in-band reduced transition probabilities are ~1-2 Weisskopf units assuming magnetic dipole transitions. The measured lifetimes in conjunction with the partial level scheme support an oblate collective interpretation for these structures.

T. F. Wang; E. A. Henry; J. A. Becker; A. Kuhnert; M. A. Stoyer; S. W. Yates; M. J. Brinkman; J. A. Cizewski; A. O. Macchiavelli; F. S. Stephens; M. A. Deleplanque; R. M. Diamond; J. E. Draper; F. A. Azaiez; W. H. Kelly; W. Korten; E. Rubel; Y. A. Akovali

1992-01-01

208

Efforts to develop excess-carrier recombination lifetime measurement standards for silicon PV  

Microsoft Academic Search

The excess carrier recombination lifetime in silicon solar cells is a critical indicator of material and passivation quality. This property can be measured on silicon crystals and then at every stage of production. As the silicon PV field has developed, many methods of measuring this carrier lifetime are coming into use, including mapping methods such as microwave-photoconductance decay, imaging methods

Ronald A. Sinton; Sinton Instruments

2010-01-01

209

Measurement of the B0 and B+ lifetimes  

Microsoft Academic Search

From a data sample of approximately 240 000 hadronic Z0 decays recorded during 1991 a sample of about 130 semileptonic B hadron decays containing a D0, D+ or D*+ has been isolated. Using silicon microvertex detector information the decay vertices in these events have been reconstructed. The average B hadron lifetime of the mix of B hadrons in this event

P. D. Acton; Gideon Alexander; J. Allison; P. P. Allport; K. J. Anderson; S. Arcelli; Alan Astbury; D A Axen; Georges Azuelos; G. A. Bahan; J. T. M. Baines; A. H. Ball; J. Banks; R. J. Barlow; S. Barnett; J Richard Batley; G. Beaudoin; A. Beck; G. A. Beck; J. Becker; T. Behnke; K. W. Bell; G. Bella; P. Bentkowski; P. Berlich; Siegfried Bethke; O. Biebel; U. Binder; Ian J Bloodworth; P. Bock; B. Boden; H. M. Bosch; Horst Breuker; P G Bright-Thomas; R. M. Brown; A. Buijs; Helfried J Burckhart; C. Burgard; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; D. G. Charlton; S. L. Chu; P. E. L. Clarke; I. Cohen; J. C. Clayton; W. J. Collins; J. E. Conboy; M. Cooper; M. Coupland; M. Cuffiani; S. Dado; G M Dallavalle; S. de Jong; L. A. del Pozo; H. Deng; A. Dieckmann; Michael Dittmar; M. S. Dixit; E. Do Couto E Silva; J. E. Duboscq; E. Duchovni; G. Duckeck; I. P. Duerdoth; D. J. P. Dumas; P. A. Elcombe; P. G. Estabrooks; E. Etzion; H. G. Evans; Franco Luigi Fabbri; M. Fierro; Margret Fincke-Keeler; H. M. Fischer; D. G. Fong; M. Foucher; A. Gaidot; O. Ganel; J. W. Gary; J. Gascon; R. F. McGowan; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; G. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; James D Gillies; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; F. C. Grant; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. F. Harrison; J. Hart; P. M. Hattersley; M. Hauschild; C. M. Hawkes; E. Heflin; Richard J Hemingway; R. D. Heuer; J. C. Hill; S. J. Hillier; T. Hilse; D. A. Hinshaw; J. D. Hobbs; P. R. Hobson; D. Hochman; R James Homer; A. K. Honma; R. E. Hughes-Jones; R. Humbert; P. Igo-Kemenes; H. Ihssen; D. C. Imrie; A. C. Janissen; A. Jawahery; P. W. Jeffreys; H. Jeremie; Martin Paul Jimack; M. Jobes; R. W. L. Jones; P. Jovanovic; C. Jui; D A Karlen; K. Kawagoe; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; S. Kluth; T. Kobayashi; D. S. Koetke; T. P. Kokott; S. Komamiya; L. Köpke; J. F. Kral; R V Kowalewski; J. von Krogh; J. Kroll; M Kuwano; P. Kyberd; G. D. Lafferty; R. Lahmann; F. Lamarche; J. G. Layter; P. Leblanc; A. M. Lee; M. H. Lehto; Daniel Lellouch; C. Leroy; J. Letts; S. Levegrün; L. Levinson; S. L. Lloyd; F. K. Loebinger; J. M. Lorah; B. Lorazo; Michael J Losty; X. C. Lou; J. Ludwig; M. Mannelli; S. Marcellini; G. Maringer; C. Markus; A. J. Martin; J. P. Martin; T. Mashimo; P. Mättig; U. Maur; J A McKenna; T. J. McMahon; J. R. McNutt; F. Meijers; D. Menszner; F. S. Merritt; H. Mes; Aldo Michelini; R. P. Middleton; G. Mikenberg; J L Mildenberger; D. J. Miller; R. Mir; W. Mohr; C. Moisan; A. Montanari; T. Mori; M. Morii; T. Mouthuy; B. Nellen; H. H. Nguyen; M. Nozaki; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; C. J. Oram; M. J. Oreglia; S. Orito; J. P. Pansart; B. Panzer-Steindel; P. Paschievici; G. N. Patrick; N. Paz-Jaoshvili; P. Pfister; J. E. Pilcher; James L Pinfold; D. Pitman; D. E. Plane; P R Poffenberger; B. Poli; A. Pouladdej; T. W. Pritchard; H. Przysiezniak; G. Quast; M. W. Redmond; D. L. Rees; G. E. Richards; D. Robinson; A. Rollnik; J. M. Roney; E. Ros; S. Rossberg; A. M. Rossi; M. Rosvick; P. Routenburg; K. Runge; O. Runolfsson; D. R. Rust; M. Sasaki; C. Sbarra; A. D. Schaile; O. Schaile; W. Schappert; P. Scharff-Hansen; P. Schenk; B. Schmitt; H. von der Schmitt; S. Schreiber; C. Schwick; J. Schwiening; W. G. Scott; M. Settles; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; R L Shypit; A. Simon; P. Singh; G. P. Siroli; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; Randall J Sobie; R. W. Springer; M. Sproston; K. Stephens; J. Steuerer; R. Ströhmer; D. Strom; T. Takeshita; P. Taras; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; N. J. Thackray; M. A. Thomson; E. Torrente-Lujan; G. Transtromer; N. J. Tresilian; T. Tsukamoto; M. F. Turner; G. Tysarczyk-Niemeyer; D. van den Plas; R. van Kooten; G. J. Vandalen; G. Vasseur; C. J. Virtue; A. Wagner; D. L. Wagner; C. Wahl; J. P. Walker; C. P. Ward; D. R. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; M. Weber; P. Weber; P. S. Wells; N. Wermes; M. A. Whalley; G. W. Wilson; J. A. Wilson; V.-H. Winterer; T. Wlodek; S A Wotton; T. R. Wyatt; R. Yaari; A. Yeaman; G. Yekutieli; M. Yurko; W. Zeuner; G. T. Zorn

1993-01-01

210

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

211

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...

212

Wavelength-resolved measurements of fluorescence lifetime of indocyanine green  

NASA Astrophysics Data System (ADS)

We study fluorescence lifetime of indocyanine green (ICG) using femtosecond laser and sensitive detection based on time-correlated single-photon counting. A time-resolved multichannel spectral system is constructed and applied for determination of the fluorescence lifetime of the ICG in different solvents. Emission properties of ICG in water, milk, and 1% intralipid solution are investigated. Fluorescence of the fluorophore of different concentrations (in a range of 1.7-160 ?M) dissolved in different solutions is excited by femtosecond pulses generated with the use of Ti:Sa laser tuned within the range of 740-790 nm. It is observed that fluorescence lifetime of ICG in water is 0.166 +/- 0.02 ns and does not depend on excitation and emission wavelengths. We also show that for the diffusely scattering solvents (milk and intralipid), the lifetime may depend on the dye concentration (especially for large concentrations of ICG). This effect should be taken into account when analyzing changes in the mean time of arrival of fluorescence photons excited in ICG dissolved in such optically turbid media.

Gerega, Anna; Zolek, Norbert; Soltysinski, Tomasz; Milej, Daniel; Sawosz, Piotr; Toczylowska, Beata; Liebert, Adam

2011-06-01

213

Comparison of the Electron Momentum Distribution of Solid and Liquid Ni as Measured by Positrons.  

National Technical Information Service (NTIS)

This paper compares the measured electron momentum densities seen by positrons annihilating in the defect-free Ni lattice, in vacancies and in liquid Ni. The experimental techniques and analysis method are also described. (ERA citation 06:027355)

M. J. Fluss L. C. Smedskjaer M. K. Chason

1980-01-01

214

Towards a precise measurement of the cosmic-ray positron fraction  

NASA Astrophysics Data System (ADS)

This thesis deals with detector concepts aiming at a precise measurement of the cosmic-ray positron fraction extending to an as yet unreached range of energy. The indirect search for dark matter is the main motivation for this endeavour.

Gast, Henning

2009-03-01

215

Proximity getterihg by MeV-implantation of carbon: microstructure and carrier lifetime measurements  

Microsoft Academic Search

The gettering efficiency of silicon implanted with carbon at a dose of 1 × 1016 cm-2 and energies in the range of 0.33-10 MeV was tested by carrier lifetime measurements. After an intentional contamination of the sample back side with gold as a lifetime killer, on the front side we found values for the generation lifetime of the minority carriers

W. Skorupa; R. Kögler; K. Schmalz; H. Bartsch

1991-01-01

216

Rotational band structures and lifetime measurements in 130Ce  

Microsoft Academic Search

The deformed nucleus 130Ce has been studied using the techniques of in-beam gamma -ray spectroscopy. Beams of 16O and 18O were used on targets of 116,117,118Sn to obtain excitation energies, mean lifetimes, spins, parities, mixing ratios and branching ratios. The gamma - gamma coincidence data necessary to determine the decay scheme were obtained using an array of five escape-suppressed spectrometers.

D M Todd; R Aryaeinejad; D J G Love; A H Nelson; P J Nolan; P J Smith; P J Twin

1984-01-01

217

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

NASA Astrophysics Data System (ADS)

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 obtained in the conventional way from one of the annihilation ? quanta. Compared with the conventional ?? lifetime-measurement technique, this ß+? lifetime spectrometer does not only give a substantially better time resolution but also, owing to the ß+ detector efficiency unity, a much higher coincidence count rate. This will permit routine age-momentum-correlation (AMOC) measurements, using the second annihilation photon. The positron clock can handle very high positron beam fluxes such as they will become available in e+ factories. In the Stuttgart setup we hope to reach, by using solid rare-gas moderators in the accelerator terminal, positron fluxes of about 106e+/s. A comparison between the moderation efficiencies of tungsten and rare-gas moderators under the vacuum conditions of the accelerator terminal is presented. AMOC measurements allow us to obtain time-resolved information on the evolution of the positron states (e.g., trapping of positrons at defects or positronium formation). As a surprising effect, “giant” Doppler broadening of the annihilation quanta of “young” positrons in diamond has been observed by means of a beam-based AMOC technique.

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

1992-05-01

218

Measurement of the average B hadron lifetime in Z0 decays  

Microsoft Academic Search

A sample of 689 muon candidates and 665 electron candidates identified in multihadronic Z0 decays has been used to measure the average B hadron lifetime. These data were recorded with the OPAL detector during 1990. Maximum likelihood fits to the distributions of the lepton impact parameters yield an average B hadron lifetime of taub = 1.37 +\\/- 0.07 +\\/- 0.06

P. D. Acton; G. Alexander; J. Allison; P. P. Allport; K. J. Anderson; S. Arcelli; P. Ashton; A. Astbury; D. Axen; G. Azuelos; G. A. Bahan; J. T. M. Baines; A. H. Ball; J. Banks; G. J. Barker; R. J. Barlow; J. R. Batley; G. Beaudoin; A. Beck; J. Becker; T. Behnke; K. W. Bell; G. Bella; P. Berlich; S. Bethke; O. Biebel; U. Binder; I. J. Bloodworth; P. Bock; B. Boden; H. M. Bosch; S. Bougerolle; B. B. Brabson; H. Breuker; R. M. Brown; R. Brun; A. Buijs; H. J. Burckhart; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; D. G. Charlton; P. E. L. Clarke; I. Cohen; W. J. Collins; J. E. Conboy; M. Cooper; M. Couch; M. Coupland; M. Cuffiani; S. Dado; G. M. Dallavalle; S. de Jong; P. Debu; L. A. del Pozo; M. M. Deninno; A. Dieckmann; M. Dittmar; M. S. Dixit; E. Duchovni; G. Duckeck; I. P. Duerdoth; D. J. P. Dumas; G. Eckerlin; P. A. Elcombe; P. G. Estabrooks; E. Etzion; F. Fabbri; M. Fincke-Keeler; H. M. Fischer; D. G. Fong; C. Fukunaga; A. Gaidot; O. Ganel; J. W. Gary; J. Gascon; R. F. McGowan; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; G. Giacomelli; V. Gibson; W. R. Gibson; J. D. Gillies; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; F. C. Grant; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; P. F. Harrison; J. Hart; P. M. Hattersley; M. Hauschild; C. M. Hawkes; E. Heflin; R. J. Hemingway; R. D. Heuer; J. C. Hill; S. J. Hillier; D. A. Hinshaw; C. Ho; J. D. Hobbs; P. R. Hobson; D. Hochman; B. Holl; R. J. Homer; A. K. Honma; S. R. Hou; C. P. Howarth; R. E. Hughes-Jones; R. Humbert; P. Igo-Kemenes; H. Ihssen; D. C. Imrie; A. C. Janissen; A. Jawahery; P. W. Jeffreys; H. Jeremie; M. Jimack; M. Jobes; R. W. L. Jones; P. Jovanovic; D. Karlen; K. Kawagoe; T. Kawamoto; R. K. Keeler; R. G. Kellogg; B. W. Kennedy; C. Kleinwort; D. E. Klem; T. Kobayashi; T. P. Kokott; S. Komamiya; L. Köpke; J. F. Kral; R. Kowalewski; H. Kreutzmann; J. von Krogh; J. Kroll; M. Kuwano; P. Kyberd; G. D. Lafferty; F. Lamarche; W. J. Larson; J. G. Layter; P. Le Du; P. Leblanc; A. M. Lee; M. H. Lehto; D. Lellouch; P. Lennert; C. Leroy; J. Letts; S. Levegrün; L. Levinson; S. L. Lloyd; F. K. Loebinger; J. M. Lorah; B. Lorazo; M. J. Losty; X. C. Lou; J. Ludwig; M. Mannelli; S. Marcellini; G. Maringer; A. J. Martin; J. P. Martin; T. Mashimo; P. Mättig; U. Maur; J. McKenna; T. J. McMahon; J. R. McNutt; F. Meijers; D. Menszner; F. S. Merritt; H. Mes; A. Michelini; R. P. Middleton; G. Mikenberg; J. Mildenberger; D. J. Miller; R. Mir; W. Mohr; C. Moisan; A. Montanari; T. Mori; M. W. Moss; T. Mouthuy; B. Nellen; H. H. Nguyen; M. Nozaki; S. W. O'Neale; B. P. O'Neill; F. G. Oakham; F. Odorici; M. Ogg; H. O. Ogren; H. Oh; C. J. Oram; M. J. Oreglia; S. Orito; J. P. Pansart; B. Panzer-Steindel; P. Paschievici; G. N. Patrick; S. J. Pawley; P. Pfister; J. E. Pilcher; J. L. Pinfold; D. Pitman; D. E. Plane; P. Poffenberger; B. Poli; A. Pouladdej; E. Prebys; T. W. Pritchard; H. Przysiezniak; G. Quast; M. W. Redmond; D. L. Rees; K. Riles; S. A. Robins; D. Robinson; A. Rollnik; J. M. Roney; E. Ros; S. Rossberg; A. M. Rossi; M. Rosvick; P. Routenburg; K. Runge; O. Runolfsson; D. R. Rust; S. Sanghera; M. Sasaki; A. D. Schaile; O. Schaile; W. Schappert; P. Scharff-Hansen; P. Schenk; H. von der Schmitt; S. Schreiber; J. Schwiening; W. G. Scott; M. Settles; B. C. Shen; P. Sherwood; R. Shypit; A. Simon; P. Singh; G. P. Siroli; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; R. Sobie; R. W. Springer; M. Sproston; K. Stephens; H. E. Stier; R. Ströhmer; D. Strom; H. Takeda; T. Takeshita; P. Taras; S. Tarem; P. Teixeira-Dias; N. J. Thackray; G. Transtromer; T. Tsukamoto; M. F. Turner; G. Tysarczyk-Niemeyer; D. van den Plas; R. van Kooten; G. J. Vandalen; G. Vasseur; C. J. Virtue; A. Wagner; C. Wahl; J. P. Walker; C. P. Ward; D. R. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; M. Weber; P. Weber; S. Weisz; P. S. Wells; N. Wermes; M. Weymann; M. A. Whalley; G. W. Wilson; J. A. Wilson; I. Wingerter; V.-H. Winterer; N. C. Wood; S. Wotton; T. R. Wyatt; R. Yaari; Y. Yang; G. Yekutieli; M. Yurko; I. Zacharov; W. Zeuner; G. T. Zorn

1992-01-01

219

A measurement of R b using a lifetime-mass tag  

Microsoft Academic Search

ALEPH's published measurement of Rb = ?(Z ? bb)?(Z ? hadrons) using a lifetime tag is updated using the full LEP 1 data sample. Considerable effort has been devoted to understanding systematic effects. Charm background is better controlled by combining the lifetime tag with a tag based on the bc hadron mass difference. Furthermore, the algorithm used to reconstruct the

R. Barate; Damir Buskulic; D. Decamp; P. Ghez; C. Goy; J.-P. Lees; A. Lucotte; M.-N. Minard; J.-Y. Nief; B. Pietrzyk; M. P. Casado; M. Chmeissani; P. Comas; J. M. Crespo; M C Delfino; E. Fernandez; M. Fernandez-Bosman; Ll. Garrido; A. Juste; M. Martinez; R. Miquel; Ll. M. Mir; S. Orteu; C. Padilla; I. C. Park; A. Pascual; J. A. Perlas; I. Riu; F. Sanchez; F. Teubert; A. Colaleo; D. Creanza; M. de Palma; G. Gelao; Giuseppe Iaselli; G. Maggi; M. Maggi; N. Marinelli; S. Nuzzo; A. Ranieri; G. Raso; F. Ruggieri; G. Selvaggi; L. Silvestris; P. Tempesta; A. Tricomi; G. Zito; X. Huang; J. Lin; Q. Ouyang; T. Wang; Y. Xie; R. Xu; S. Xue; J. Zhang; L. Zhang; W. Zhao; D. Abbaneo; R. Alemany; U. Becker; A. O. Bazarko; P G Bright-Thomas; M. Cattaneo; F. Cerutti; H. Drevermann; Roger W Forty; M. Frank; R. Hagelberg; J. Harvey; P. Janot; B. Jost; E. Kneringer; J. Knobloch; Ivan Lehraus; G. Lutters; P. Mato; Adolf G Minten; L. Moneta; A. Pacheco; J.-F. Pusztaszeri; F. Ranjard; P E Rensing; G. Rizzo; Luigi Rolandi; D. Schlatter; M. Schmitt; O. Schneider; W. Tejessy; I. R. Tomalin; H W Wachsmuth; A. Wagner; Ziad J Ajaltouni; A. Barrès; C. Boyer; A. Falvard; C. Ferdi; P. Gay; C. Guicheney; P. Henrard; J. Jousset; B. Michel; S. Monteil; J. C. Montret; D. Pallin; P. Perret; F. Podlyski; J. Proriol; P. Rosnet; J.-M. Rossignol; Tom Fearnley; J. B. Hansen; J. D. Hansen; P. H. Hansen; B. S. Nilsson; B. Rensch; A. Wäänänen; G. Daskalakis; A. Kyriakis; C. Markou; Errietta Simopoulou; I. Siotis; Anna Vayaki; A. Blondel; G R Bonneaud; J. C. Brient; P. Bourdon; A. Rougé; M. Rumpf; Andrea Valassi; M. Verderi; H L Videau; D. J. Candlin; M. I. Parsons; E. Focardi; G. Parrini; K. Zachariadou; M. Corden; C H Georgiopoulos; D. E. Jaffe; A. Antonelli; G. Bencivenni; G. Bologna; F. Bossi; P. Campana; G. Capon; David William 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; J. M. Scarr; K. Smith; P. Teixeira-Dias; A. S. Thompson; E. Thomson; F. Thomson; R. M. Turnbull; C. Geweniger; G. Graefe; P. Hanke; G. Hansper; V. Hepp; E. E. Kluge; A. Putzer; M. Schmidt; J. Sommer; K. Tittel; S. Werner; M. Wunsch; R. Beuselinck; David M Binnie; W. Cameron; Peter J Dornan; M. Girone; S M Goodsir; E. B. Martin; A. Moutoussi; J. Nash; J. K. Sedgbeer; A. M. Stacey; M. D. Williams; G. Dissertori; V. M. Ghete; P. Girtler; D. Kuhn; G. Rudolph; A. P. Betteridge; C. K. Bowdery; P. Colrain; G. Crawford; A. J. Finch; F. Foster; G. Hughes; Terence Sloan; M. I. Williams; A. Galla; I. Giehl; A. M. Greene; C. Hoffmann; K. Jakobs; K. Kleinknecht; G. Quast; B. Renk; E. Rohne; H.-G. Sander; P. van Gemmeren; C. Zeitnitz; Jean-Jacques Aubert; C. Benchouk; A. Bonissent; G. Bujosa; D. Calvet; J. Carr; P. Coyle; C A Diaconu; F. Etienne; N P Konstantinidis; O. Leroy; F. Motsch; P. Payre; D. Rousseau; M. Talby; A. Sadouki; M. Thulasidas; K. Trabelsi; M. Aleppo; F. Ragusa; R. Berlich; Walter Blum; D. Brown; V. Büscher; H. Dietl; Friedrich Dydak; G. Ganis; C. Gotzhein; 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. St. Denis; H. Stenzel; W. Wiedenmann; G. Wolf; J. Boucrot; O. Callot; S. Chen; Y. Choi; A. Cordier; M. Davier; L. Duflot; J.-F. Grivaz; Ph. Heusse; A. Höcker; A. Jacholkowska; M. Jacquet; D. W. Kim; F R Le Diberder; J. Lefrançois; A.-M. Lutz; I A Nikolic; M.-H. Schune; S. Simion; E. Tournefier; J.-J. Veillet; I. Videau; D. Zerwas; 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; Fabrizio Palla; G. Sanguinetti; A. Sciabà; P. Spagnolo; Jack Steinberger; Roberto Tenchini; G. Tonelli; C. Vannini; A. Venturi; P. G. Verdini; G. A. Blair; L. M. Bryant; J. T. Chambers; Y. Gao; M. G. Green; T. Medcalf; P. Perrodo; J. A. Strong; J. H. von Wimmersperg-Toeller; David 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; Witold Kozanecki; E. Lançon; M. C. Lemaire; E. Locci; 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 L Cartwright; F. Combley; M. S. Kelly; M H Lehto; W. M. Newton; J. Reeve; L. F. Thompson; A. Böhrer; S. Brandt; G D Cowan; Claus Grupen; P. Saraiva; L. Smolik; F. Stephan; M. Apollonio; L. Bosisio; R. Della Marina; G. Giannini; B. Gobbo; G. Musolino; J E Rothberg

1997-01-01

220

QSS-?PCD measurement of lifetime in silicon wafers: advantages and new applications  

Microsoft Academic Search

We present a version of microwave photoconductance decay, ?PCD, measurement of lifetime in silicon photovoltaics which enables simultaneous determination of the carrier decay lifetime, ?eff, and injection level, ?n, with the capability of scanning over a broad range of steady state generation including 1 sun. The present ?PCD version, referred to as QSS-?PCD, is a refined bias light PCD. It

Marshall Wilson; Alexandre Savtchouk; Jacek Lagowski; Krisztian Kis-Szabo; Ferenc Korsos; Atilla Toth; Radovan Kopecek; Valentin Mihailetchi

2011-01-01

221

Minority Carrier Lifetime Measurement in HF Solution to Evaluate Si Substrates for Solar Cells  

Microsoft Academic Search

Minority carrier lifetime measurement using a microwave photoconductivity decay method was examined. A simple method of immersing a silicon wafer in a toxic HF solution by using a plastic envelope is introduced. An effective lifetime in 50% HF solution is much higher than that in air due to reduction of the surface recombination velocity and is almost the same compared

Takayuki Nammori; Koji Okamoto; Tohru Nunoi; Yutaka Hayashi

1990-01-01

222

Carrier Lifetime Measurements by Microwave Photoconductive Decay Method at Low Injection Levels  

Microsoft Academic Search

The minority carrier lifetime of Si wafers has been measured at very low injection levels by employing a newly developed microwave photoconductive decay (mu-PCD) technique. It is found that the effective lifetime is dramatically increased for the case of p-type Si when the injection level is reduced to two orders of magnitude less than the equilibrium value. In contrast to

Chiyo Fujihira; Michel Morin; Hidehisa Hashizume; Jean Friedt; Yasuhide Nakai; Masataka Hirose

1993-01-01

223

Study of Applicability of AC Photovoltaic Method and Photoconductive Decay Method Using Microwaves as Noncontact Methods for Bulk Lifetime Measurement  

NASA Astrophysics Data System (ADS)

The applicability of the ac photovoltaic method and photoconductive decay method using microwaves (?-PCD method) as bulk lifetime measurement methods were studied. Lifetimes measured by these two methods were compared with bulk lifetimes measured by the photoconductive decay method standardized by ASTM:F28-75. Lifetimes measured by the ac photovoltaic method were in good agreement with the bulk lifetimes of less than 3 ms for both n-type and p-type samples. However, lifetimes measured by the ?-PCD method were significantly lower than the bulk lifetimes. It is concluded that the ac photovoltaic method is a reliable noncontact method for the bulk lifetime measurement of the samples with bulk lifetimes less than 3 ms.

Toda, Masato; Kitagawara, Yutaka; Takenaka, Takao

1993-07-01

224

Study of applicability of AC photovoltaic method and photoconductive decay method using microwaves as noncontact methods for bulk lifetime measurement  

NASA Astrophysics Data System (ADS)

The applicability of the ac photovoltaic method and photoconductive decay method using microwaves (mu-PCD method) as bulk lifetime measurement methods were studied. Lifetimes measured by these two methods were compared with bulk lifetimes measured by the photoconductive decay method standardized by ASTM:F28-75. Lifetimes measured by the ac photovoltaic method were in good agreement with the bulk lifetimes of less than 3 ms for both n-type and p-type samples. However, lifetimes measured by the mu-PCD method were significantly lower than the bulk lifetimes. It is concluded that the ac photovoltaic method is a reliable noncontact method for the bulk lifetime measurement of the samples with bulk lifetimes less than 3 ms.

Toda, Masato; Kitagawara, Yutaka; Takenaka, Takao

1993-07-01

225

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

Microsoft Academic Search

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

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

1997-01-01

226

Measurement of the Lambdab Lifetime in the Exclusive Decay Lambdab-->J\\/psiLambda  

Microsoft Academic Search

We have measured the Lambdab lifetime using the exclusive decay Lambdab-->J\\/psiLambda, based on 1.2fb-1 of data collected with the D0 detector during 2002 2006. From 171 reconstructed Lambdab decays, where the J\\/psi and Lambda are identified via the decays J\\/psi-->mu+mu- and Lambda-->ppi, we measured the Lambdab lifetime to be tau(Lambdab)=1.218-0.115+0.130(stat)±0.042(syst)ps. We also measured the B0 lifetime in the decay B0-->J\\/psi(mu+mu-)KS0(pi+pi-)

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

2007-01-01

227

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

228

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

229

In Pursuit of Highly Accurate Atomic Lifetime Measurements of Multiply Charged Ions  

SciTech Connect

Accurate atomic lifetime data are useful for terrestrial and astrophysical plasma diagnostics. At accuracies higher than those required for these applications, lifetime measurements test atomic structure theory in ways complementary to spectroscopic energy determinations. At the highest level of accuracy, the question arises whether such tests reach the limits of modern theory, a combination of quantum mechanics and QED, adn possibly point to physics beyond the Standard Model. If high-precision atomic lifetime measurements, especially on multiply charged ions, have not quite reached this high accuracy yet, then what is necessary to attain this goal?

Tr?bert, E

2009-06-01

230

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

231

Carrier lifetime measurement in n- 4H-SiC epilayers  

NASA Astrophysics Data System (ADS)

The effects of measurement technique and measurement conditions (e.g., injection level, temperature) on measured carrier lifetimes in n- 4H-SiC epilayers are investigated both experimentally and through detailed carrier dynamics simulations to better understand differences between reported lifetimes. Three common, optically based techniques are compared: time resolved photoluminescence, transient free carrier absorption, and microwave photoconductivity decay. From the details of these measurement techniques it is shown from both theory and experiment that for the limits of high or low injection, these techniques can reflect very different lifetimes. The effect of measurement conditions on the carrier lifetime was approached by simulating the carrier dynamics assuming a dominant Z1/Z2 defect in order to calculate the evolution of the lifetimes and the carrier and defect charge state concentrations for arbitrary injection level or temperature, as a closed-form solution to this problem does not exist. The simulated behavior was found to be in reasonable agreement with experiment and the resulting values for the electron and hole capture cross sections for the 0/+ transition of Z1/Z2 were found to be ?n2~(2-4)×10-15 cm2 and ?p2~(1-2)×10-14 cm2, respectively. The simulations provide insight into the dominant processes controlling the lifetime and identify four distinct stages of decay. A simple expression for the ratio of high- to low-injection lifetimes is presented which compares well with experiment. The temperature dependence of the lifetime is found to be relatively weak below 500 K and thermally activated immediately above this temperature due to electron emission from the Z0 state. Electron emission from Z- and hole emission become important only at higher temperatures. Simulations with both Z1/Z2 and EH6/EH7 defects suggest the latter does not contribute significantly to the lifetime in as-grown epilayers, due primarily to a small capture cross section for holes.

Klein, P. B.

2008-02-01

232

Measurement of the lifetime in pp collisions at TeV  

NASA Astrophysics Data System (ADS)

A measurement of the lifetime using the decay in protonproton collisions at TeV is presented. The data set, corresponding to an integrated luminosity of about 5 fb-1, was recorded with the CMS experiment at the Large Hadron Collider using triggers that selected dimuon events in the J/ ? mass region. The lifetime is measured to be 1.503 ± 0.052 (stat.) ± 0.031 (syst.) ps. [Figure not available: see fulltext.

Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Knünz, V.; Krammer, M.; Krätschmer, I.; Liko, D.; Mikulec, I.; Rabady, D.; Rahbaran, B.; Rohringer, C.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Taurok, A.; Treberer-Treberspurg, W.; Waltenberger, W.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Alderweireldt, S.; Bansal, M.; Bansal, S.; Cornelis, T.; De Wolf, E. A.; Janssen, X.; Knutsson, A.; Luyckx, S.; Mucibello, L.; Ochesanu, S.; Roland, B.; Rougny, R.; Van Haevermaet, H.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Blekman, F.; Blyweert, S.; D'Hondt, J.; Kalogeropoulos, A.; Keaveney, J.; Maes, M.; Olbrechts, A.; Tavernier, S.; Van Doninck, W.; Van Mulders, P.; Van Onsem, G. P.; Villella, I.; Clerbaux, B.; De Lentdecker, G.; Favart, L.; Gay, A. P. R.; Hreus, T.; Léonard, A.; Marage, P. E.; Mohammadi, A.; Reis, T.; Seva, T.; Thomas, L.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Adler, V.; Beernaert, K.; Benucci, L.; Cimmino, A.; Costantini, S.; Dildick, S.; Garcia, G.; Klein, B.; Lellouch, J.; Marinov, A.; Mccartin, J.; Ocampo Rios, A. A.; Ryckbosch, D.; Sigamani, M.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Walsh, S.; Yazgan, E.; Zaganidis, N.; Basegmez, S.; Beluffi, C.; Bruno, G.; Castello, R.; Caudron, A.; Ceard, L.; Delaere, C.; du Pree, T.; Favart, D.; Forthomme, L.; Giammanco, A.; Hollar, J.; Lemaitre, V.; Liao, J.; Militaru, O.; Nuttens, C.; Pagano, D.; Pin, A.; Piotrzkowski, K.; Popov, A.; Selvaggi, M.; Vizan Garcia, J. M.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Alves, G. A.; Correa Martins, M.; Martins, T.; Pol, M. E.; Souza, M. H. G.; Aldá, W. L.; Carvalho, W.; Chinellato, J.; Custódio, A.; Da Costa, E. M.; De Jesus Damiao, D.; De Oliveira Martins, C.; Fonseca De Souza, S.; Malbouisson, H.; Malek, M.; Matos Figueiredo, D.; Mundim, L.; Nogima, H.; Prado Da Silva, W. L.; Santoro, A.; Soares Jorge, L.; Sznajder, A.; Tonelli Manganote, E. J.; Vilela Pereira, A.; Anjos, T. S.; Bernardes, C. A.; Dias, F. A.; Fernandez Perez Tomei, T. R.; Gregores, E. M.; Lagana, C.; Marinho, F.; Mercadante, P. G.; Novaes, S. F.; Padula, Sandra S.; Genchev, V.; Iaydjiev, P.; Piperov, S.; Rodozov, M.; Sultanov, G.; Vutova, M.; Dimitrov, A.; Hadjiiska, R.; Kozhuharov, V.; Litov, L.; Pavlov, B.; Petkov, P.; Bian, J. G.; Chen, G. M.; Chen, H. S.; Jiang, C. H.; Liang, D.; Liang, S.; Meng, X.; Tao, J.; Wang, J.; Wang, X.; Wang, Z.; Xiao, H.; Xu, M.; Asawatangtrakuldee, C.; Ban, Y.; Guo, Y.; Li, W.; Liu, S.; Mao, Y.; Qian, S. J.; Teng, H.; Wang, D.; Zhang, L.; Zou, W.; Avila, C.; Carrillo Montoya, C. A.; Gomez, J. P.; Gomez Moreno, B.; Sanabria, J. C.; Godinovic, N.; Lelas, D.; Plestina, R.; Polic, D.; Puljak, I.; Antunovic, Z.; Kovac, M.; Brigljevic, V.; Duric, S.; Kadija, K.; Luetic, J.; Mekterovic, D.; Morovic, S.; Tikvica, L.; Attikis, A.; Mavromanolakis, G.; Mousa, J.; Nicolaou, C.; Ptochos, F.; Razis, P. A.; Finger, M.; Finger, M.; Assran, Y.; Ellithi Kamel, A.; Mahmoud, M. A.; Mahrous, A.; Radi, A.; Kadastik, M.; Müntel, M.; Murumaa, M.; Raidal, M.; Rebane, L.; Tiko, A.; Eerola, P.; Fedi, G.; Voutilainen, M.; Härkönen, J.; Karimäki, V.; Kinnunen, R.; Kortelainen, M. J.; Lampén, T.; Lassila-Perini, K.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Peltola, T.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Wendland, L.; Korpela, A.; Tuuva, T.; Besancon, M.; Choudhury, S.; Couderc, F.; Dejardin, M.; Denegri, D.; Fabbro, B.; Faure, J. L.; Ferri, F.; Ganjour, S.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Locci, E.; Malcles, J.; Millischer, L.; Nayak, A.; Rander, J.; Rosowsky, A.; Titov, M.; Baffioni, S.; Beaudette, F.; Benhabib, L.; Bianchini, L.; Bluj, M.; Busson, P.; Charlot, C.; Daci, N.; Dahms, T.; Dalchenko, M.; Dobrzynski, L.; Florent, A.; Granier de Cassagnac, R.; Haguenauer, M.; Miné, P.; Mironov, C.; Naranjo, I. N.; Nguyen, M.; Ochando, C.; Paganini, P.; Sabes, D.; Salerno, R.; Sirois, Y.; Veelken, C.; Zabi, A.; Agram, J.-L.; Andrea, J.; Bloch, D.; Bodin, D.; Brom, J.-M.; Chabert, E. C.; Collard, C.; Conte, E.; Drouhin, F.; Fontaine, J.-C.; Gelé, D.; Goerlach, U.; Goetzmann, C.; Juillot, P.; Le Bihan, A.-C.; Van Hove, P.; Gadrat, S.; Beauceron, S.; Beaupere, N.; Boudoul, G.; Brochet, S.; Chasserat, J.; Chierici, R.; Contardo, D.; Depasse, P.; El Mamouni, H.; Fay, J.; Gascon, S.; Gouzevitch, M.; Ille, B.; Kurca, T.; Lethuillier, M.; Mirabito, L.; Perries, S.; Sgandurra, L.; Sordini, V.; Tschudi, Y.; Vander Donckt, M.; Verdier, P.; Viret, S.; Tsamalaidze, Z.; Autermann, C.; Beranek, S.; Calpas, B.; Edelhoff, M.; Feld, L.; Heracleous, N.; Hindrichs, O.

2013-07-01

233

Measurement of the b baryon lifetime and branching fractions in Z decays  

Microsoft Academic Search

Using approximately 4 million hadronic Z decays recorded with the Aleph detector from 1991 through 1995, the lifetime of the b baryon is measured with three independent methods. From the impact parameter distribution of candidate leptons in 1063 events with Lambda-lepton combinations, the average b baryon lifetime is measured to be 1.20 +-0.08 +-0.06 ps. From a sample of 193

R Barate; Damir Buskulic; D Décamp; P Ghez; C Goy; J P Lees; A Lucotte; M N Minard; J Y Nief; B Pietrzyk; M P Casado; M Chmeissani; P Comas; J M Crespo; M C Delfino; E Fernández; M Fernández-Bosman; L Garrido; A Juste; M Martínez; G Merino; R Miquel; L M Mir; C Padilla; I C Park; A Pascual; J A Perlas; I Riu; F Sánchez; A Colaleo; D Creanza; M De Palma; G Gelao; Giuseppe Iaselli; G Maggi; M Maggi; N Marinelli; S Nuzzo; A Ranieri; G Raso; F Ruggieri; G Selvaggi; L Silvestris; P Tempesta; A Tricomi; G Zito; X Huang; J Lin; Q Ouyang; T Wang; Y Xie; R Xu; S Xue; J Zhang; L Zhang; W Zhao; D Abbaneo; R Alemany; U Becker; A O Bazarko; P G Bright-Thomas; M Cattaneo; F Cerutti; G Dissertori; H Drevermann; Roger W Forty; M Frank; R Hagelberg; J B Hansen; J Harvey; P Janot; B Jost; E Kneringer; J Knobloch; Ivan Lehraus; P Mato; Adolf G Minten; L Moneta; A Pacheco; J F Pusztaszeri; F Ranjard; G Rizzo; Luigi Rolandi; D Rousseau; W D Schlatter; M Schmitt; O Schneider; W Tejessy; F Teubert; I R Tomalin; H W Wachsmuth; A Wagner; Ziad J Ajaltouni; A Barrès; C Boyer; A Falvard; C Ferdi; P Gay; C Guicheney; P Henrard; J Jousset; B Michel; S Monteil; J C Montret; D Pallin; P Perret; F Podlyski; J Proriol; P Rosnet; J M Rossignol; Tom Fearnley; J D Hansen; J R Hansen; P H Hansen; B S Nilsson; B Rensch; A Wäänänen; G Daskalakis; A Kyriakis; C Markou; Errietta Simopoulou; I Siotis; Anna Vayaki; A Blondel; G R Bonneaud; J C Brient; P Bourdon; A Rougé; M Rumpf; Andrea Valassi; M Verderi; H L Videau; D J Candlin; M I Parsons; E Focardi; G Parrini; K Zachariadou; M Corden; C H Georgiopoulos; D E Jaffe; A Antonelli; G Bencivenni; G Bologna; F Bossi; P Campana; G Capon; David William Casper; V Chiarella; G Felici; P Laurelli; G Mannocchi; F Murtas; G P Murtas; L Passalacqua; M Pepé-Altarelli; L Curtis; S J Dorris; A W Halley; I G Knowles; J G Lynch; V O'Shea; C Raine; J M Scarr; K Smith; P Teixeira-Dias; A S Thompson; E Thomson; F Thomson; R M Turnbull; O L Buchmüller; S Dhamotharan; C Geweniger; G Graefe; P Hanke; G Hansper; V Hepp; E E Kluge; A Putzer; J Sommer; K Tittel; S Werner; M Wunsch; R Beuselinck; David M Binnie; W Cameron; Peter J Dornan; M Girone; S M Goodsir; E B Martin; A Moutoussi; J Nash; J K Sedgbeer; P Spagnolo; A M Stacey; M D Williams; V M Ghete; P Girtler; D Kuhn; G Rudolph; A P Betteridge; C K Bowdery; P G Buck; P Colrain; G Crawford; A J Finch; F Foster; G Hughes; R W L Jones; Terence Sloan; M I Williams; I Giehl; A M Greene; C Hoffmann; K Jakobs; K Kleinknecht; G Quast; B Renk; E Rohne; H G Sander; P Van Gemmeren; C Zeitnitz; Jean-Jacques Aubert; C Benchouk; A Bonissent; G Bujosa; J Carr; P Coyle; C A Diaconu; F Etienne; N P Konstantinidis; O Leroy; F Motsch; P Payre; M Talby; A Sadouki; M Thulasidas; K Trabelsi; M Aleppo; M Antonelli; F Ragusa; R Berlich; Walter Blum; V Büscher; H Dietl; G Ganis; C Gotzhein; 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; H Stenzel; W Wiedenmann; G Wolf; J Boucrot; O Callot; S Chen; Y Choi; A Cordier; M Davier; L Duflot; J F Grivaz; P Heusse; A Höcker; A Jacholkowska; M Jacquet; D W Kim; F R Le Diberder; J Lefrançois; A M Lutz; I A Nikolic; M H Schune; S Simion; E Tournefier; J J Veillet; I Videau; D Zerwas; 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; Fabrizio Palla; G Sanguinetti; A Sciabà; Jack Steinberger; Roberto Tenchini; G Tonelli; C Vannini; A Venturi; P G Verdini; G A Blair; L M Bryant; J T Chambers; Y Gao; M G Green; T Medcalf; P Perrodo; J A Strong; J H Von Wimmersperg-Töller; David R Botterill; R W Clifft; T R Edgecock; S Haywood; P R Norton; J C Thompson; A E Wright; B Bloch-Devaux; P Colas; S Emery; Witold Kozanecki; E Lançon; M C Lemaire; E Locci; P Pérez; 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 L Cartwright; F Combley; M S Kelly; M H Lehto; W M Newton; J Reeve; L F Thompson; A Böhrer; S Brandt; G D Cowan; Claus Grupen; G Lutters; P Saraiva; L Smolik; F Stephan; M Apollonio; L Bosisio; R Della Marina; G Giannini; B Gobbo; G Musolino; J E Rothberg; S R Wasserbaech; S R Armstrong; E Charles; P Elmer; D P S Ferguson; S González; T C Greening; O J Hayes; H Hu; S Jin; P A McNamara; J M Nachtman; J Nielsen; W Orejudos; Y B Pan; Y Saadi; I J Scott; J Walsh; Wu Sau Lan; X Wu; J M Yamartino; G Zobernig

1997-01-01

234

Measurement of the average b-baryon lifetime and the product branching ratio  

Microsoft Academic Search

The average lifetime of b-flavoured baryons measured with the OPAL detector is updated to include data collected between 1990\\u000a and 1994 at LEP. Bottom-flavoured baryons that decay semileptonically and produce a? baryon are identified through the correlation of the baryon number of the? and the electric charge of the lepton. To measure the lifetime, the decay point of the b

R. Akers; G. Alexander; J. Allison; N. Altekamp; K. Ametewee; K. J. Anderson; S. Anderson; S. Arcelli; S. Asai; D. Axen; G. Azuelos; A. H. Ball; E. Barberio; R. J. Barlow; R. Bartoldus; J. R. Batley; G. Beaudoin; J. Bechtluft; A. Beck; G. A. Beck; C. Beeston; T. Behnke; K. W. Bell; G. Bella; S. Bentvelsen; P. Bright-Thomas; S. Bethke; O. Biebel; I. J. Bloodworth; P. Bock; H. M. Bosch; M. Boutemeur; S. Braibant; R. M. Brown; A. Buijs; H. J. Burckhart; C. Burgard; R. Bürgin; P. Capiluppi; R. K. Carnegie; A. A. Carter; J. R. Carter; C. Y. Chang; C. Charlesworth; D. G. Charlton; S. L. Chu; P. E. L. Clarke; J. C. Clayton; S. G. Clowes; I. Cohen; J. E. Conboy; O. C. Cooke; M. Cuffiani; S. Dado; C. Dallapiccola; G. M. Dallavalle; C. Darling; S. De Jong; L. A. del Pozo; H. Deng; M. S. Dixit; E. do Couto e Silva; J. E. Duboscq; E. Duchovni; G. Duckeck; I. P. Duerdoth; U. C. Dunwoody; J. E. G. Edwards; P. G. Estabrooks; H. G. Evans; F. Fabbri; B. Fabbro; M. Fanti; P. Fath; F. Fiedler; M. Fierro; M. Fincke-Keeler; H. M. Fischer; R. Folman; D. G. Fong; M. Foucher; H. Fukui; A. Fürtjes; P. Gagnon; A. Gaidot; J. W. Gary; J. Gascon; S. M. Gascon-Shotkin; N. I. Geddes; C. Geich-Gimbel; S. W. Gensler; F. X. Gentit; T. Geralis; G. Giacomelli; P. Giacomelli; R. Giacomelli; V. Gibson; W. R. Gibson; J. D. Gillies; D. M. Gingrich; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; E. Gross; 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; G. Herten; R. D. Heuer; J. C. Hill; S. J. Hillier; T. Hilse; P. R. Hobson; D. Hochman; R. J. Homer; A. K. Honma; R. Howard; R. E. Hughes-Jones; D. E. Hutchcroft; P. Igo-Kemenes; D. C. Imrie; A. Jawahery; P. W. Jeffreys; H. Jeremie; M. Jimack; A. Joly; M. Jones; R. W. L. Jones; P. Jovanovic; J. Kanzaki; D. Karlen; K. Kawagoe; T. Kawamoto; R. K. Keeler; R. G. Kellogg; B. W. Kennedy; B. J. King; J. King; J. Kirk; S. Kluth; T. Kobayashi; M. Kobel; D. S. Koetke; T. P. Kokott; S. Komamiya; R. Kowalewski; T. Kress; P. Krieger; J. von Krogh; P. Kyberd; G. D. Lafferty; H. Lafoux; R. Lahmann; W. P. Lai; D. Lanske; J. Lauber; J. G. Layter; A. M. Lee; E. Lefebvre; D. Lellouch; J. Letts; L. Levinson; S. L. Lloyd; F. K. Loebinger; G. D. Long; B. Lorazo; M. J. Losty; J. Ludwig; A. Luig; A. Malik; M. Mannelli; S. Marcellini; C. Markus; A. J. Martin; J. P. Martin; T. Mashimo; W. Matthews; P. Mättig; J. McKenna; E. A. Mckigney; T. J. McMahon; A. I. McNab; F. Meijers; S. Menke; F. S. Merritt; H. Mes; A. Michelini; G. Mikenberg; D. J. Miller; R. Mir; W. Mohr; A. Montanari; T. Mori; M. Morii; U. Müller; B. Nellen; B. Nijjhar; S. W. O’Neale; F. G. Oakham; F. Odorici; H. O. Ogren; N. J. Oldershaw; C. J. Oram; M. J. Oreglia; S. Orito; F. Palmonari; J. P. Pansart; G. N. Patrick; M. J. Pearce; P. D. Phillips; J. E. Pilcher; J. Pinfold; D. E. Plane; P. Poffenberger; B. Poli; A. Posthaus; T. W. Pritchard; H. Przysiezniak; M. W. Redmond; D. L. Rees; D. Rigby; M. G. Rison; S. A. Robins; N. Rodning; J. M. Roney; E. Ros; A. M. Rossi; M. Rosvick; P. Routenburg; Y. Rozen; K. Runge; O. Runolfsson; D. R. Rust; M. Sasaki; C. Sbarra; A. D. Schaile; O. Schaile; F. Scharf; P. Scharff-Hansen; P. Schenk; B. Schmitt; M. Schröder; H. C. Schultz-Coulon; M. Schulz; P. Schütz; J. Schwiening; W. G. Scott; M. Settles; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; G. P. Siroli; A. Skillman; A. Skuja; A. M. Smith; T. J. Smith; G. A. Snow; R. Sobie; S. Söldner-Rembold; R. W. Springer; M. Sproston; A. Stahl; M. Starks; C. Stegmann; K. Stephens; J. Steuerer; B. Stockhausen; D. Strom; P. Szymanski; R. Tafirout; P. Taras; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; M. A. Thomson; E. von Törne; S. Towers; M. Tscheulin; T. Tsukamoto; A. S. Turcot; M. F. Turner-Watson; P. Utzat; R. Van Kooten; G. Vasseur; P. Vikas; M. Vincter; F. Wäckerle; A. Wagner; D. L. Wagner; C. P. Ward; D. R. Ward; J. J. Ward; P. M. Watkins; A. T. Watson; N. K. Watson; P. Weber; P. S. Wells; N. Wermes; B. Wilkens; G. W. Wilson; J. A. Wilson; T. Wlodek; G. Wolf; S. Wotton; T. R. Wyatt; G. Yekutieli; V. Zacek; W. Zeuner; G. T. Zorn

1995-01-01

235

B physics: measurement of the lifetime difference between b_s mass eigenstates  

SciTech Connect

We present measurements of the lifetimes and polarization amplitudes for B{sub s}{sup 0} {yields} J/{psi}{phi} and B{sub d}{sup 0} {yields} J/{psi} K*{sup 0} decays. Lifetimes of the heavy (H) and light (L) mass eigenstates in the B{sub s}{sup 0} 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.

Acosta, D.; The CDF Collaboration

2005-04-28

236

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

237

Bulk carrier lifetime measurement by the microwave reflectance photoconductivity decay method with external surface electric field  

Microsoft Academic Search

We attempted to measure the bulk carrier recombination lifetime of Si wafers by the microwave reflectance photoconductivity decay (PCD) method. Voltage was applied between an external electrode and a Si wafer to suppress surface recombination. Before the measurement, the surface state density was reduced by a chemical treatment using NH4OH-H2O2-H2O and diluted HF solutions. Carrier lifetime as long as 1

Masaya Ichimura; Atsushi Tada; Eisuke Arai; Hiroyuki Takamatsu; Shingo Sumie

2002-01-01

238

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

239

Level lifetimes in the stable Zr nuclei: Effects of chemical properties in Doppler-shift measurements  

NASA Astrophysics Data System (ADS)

The lifetime of the second excited 2+ state of 94Zr at 1671 keV was determined with the Doppler-shift attenuation method (DSAM) following the (n,n'?) reaction on scattering samples of Zr metal and ZrO2 of natural isotopic abundance. The measured lifetime, ?=368?23+27 fs, is considerably longer than the previous measurement, as are measured lifetimes of other levels in 94Zr. However, lifetimes of low-lying, low-spin states in 90,91,92,96Zr were also determined and found to be in good agreement with measurements employing non-DSAM methods. Possible reasons for the discrepant lifetimes measured for 94Zr are discussed and focus on the chemical properties of the scattering sample, specifically, the effects of using amorphous materials, or those composed of small particles as scattering samples. These properties have been investigated by x-ray powder diffraction and scanning electron microscopy. The effects of using these materials for lifetime measurements were investigated by employing, as scattering samples, Zr(OH)4 (a known amorphous material) and ZrO2 with various crystalline domain sizes.

Peters, E. E.; Chakraborty, A.; Crider, B. P.; Davis, B. H.; Gnanamani, M. K.; McEllistrem, M. T.; Prados-Estévez, F. M.; Vanhoy, J. R.; Yates, S. W.

2013-08-01

240

New measurement of the cosmic-ray positron fraction from 5 to 15 GeV.  

PubMed

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 nonstandard 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. PMID:15697790

Beatty, J J; Bhattacharyya, A; Bower, C; Coutu, S; Duvernois, M A; McKee, S; Minnick, S A; Müller, D; Musser, J; Nutter, S; Labrador, A W; Schubnell, M; Swordy, S; Tarlé, G; Tomasch, A

2004-12-09

241

Characterization of free volume during vulcanization of styrene butadiene rubber by means of positron annihilation lifetime spectroscopy and dynamic mechanical test.  

PubMed

An experimental investigation was performed to study the effect on the free volume of the advance of the cross-linking reaction in a copolymer of styrene butadiene rubber by sulfur vulcanization. The dynamic modulus and loss tangent were evaluated over samples cured for different times at 433 K by dynamic mechanical tests over a range of frequencies between 5 and 80 Hz at temperatures between 200 and 300 K. Using the William-Landel-Ferry relationship, master curves were obtained at a reference temperature of 298 K and the coefficients c(0)(1) and c(0)(2) were evaluated. From these parameters the dependence of the free volume on the cure time is obtained. Positron annihilation lifetime spectroscopy was also used to estimate the size and number density of free volume sites in the material. The spectra were analyzed in terms of continuous distributions of free volume size. The results suggest an increase of the lower free volume size when cross linking takes place. Both techniques give similar results for the dependence of free volume on the time of cure of the polymer. PMID:11863549

Marzocca, A J; Cerveny, S; Salgueiro, W; Somoza, A; Gonzalez, L

2002-01-15

242

Characterization of free volume during vulcanization of styrene butadiene rubber by means of positron annihilation lifetime spectroscopy and dynamic mechanical test  

NASA Astrophysics Data System (ADS)

An experimental investigation was performed to study the effect on the free volume of the advance of the cross-linking reaction in a copolymer of styrene butadiene rubber by sulfur vulcanization. The dynamic modulus and loss tangent were evaluated over samples cured for different times at 433 K by dynamic mechanical tests over a range of frequencies between 5 and 80 Hz at temperatures between 200 and 300 K. Using the William-Landel-Ferry relationship, master curves were obtained at a reference temperature of 298 K and the coefficients c01 and c02 were evaluated. From these parameters the dependence of the free volume on the cure time is obtained. Positron annihilation lifetime spectroscopy was also used to estimate the size and number density of free volume sites in the material. The spectra were analyzed in terms of continuous distributions of free volume size. The results suggest an increase of the lower free volume size when cross linking takes place. Both techniques give similar results for the dependence of free volume on the time of cure of the polymer.

Marzocca, A. J.; Cerveny, S.; Salgueiro, W.; Somoza, A.; Gonzalez, L.

2002-02-01

243

Positron Annihilation Lifetime Spectroscopy Study of Neutron Irradiated High Temperature Superconductors YBa2Cu3O7-? for Application in Fusion Facilities  

NASA Astrophysics Data System (ADS)

This study focuses on the crystallographic defects introduced by neutron irradiation and the resulting changes of the superconducting properties in the high temperature superconductor YBa2Cu3O7-?. This material is considered to be most promising for magnet systems in future fusion reactors. Two different bulk samples, pure non-doped YBa2Cu3O7-? (YBCO) and multi-seed YBa2Cu3O7-? doped by platinum (MS2F) were studied prior to and after irradiation in the TRIGA MARK II reactor in Vienna. Neutron irradiation is responsible for a significant enhancement of the critical current densities as well as for a reduction in critical temperature. The accumulation of small open volume defects (<0.5 nm) partially causes those changes. These defects were studied by positron annihilation lifetime spectroscopy at room temperature. A high concentration of Cu-O di-vacancies was found in both samples, which increased with neutron fluence. The defect concentration was significantly reduced after a heat treatment.

Veterníková, J.; Chudý, M.; Sluge?, V.; Eisterer, M.; Weber, H. W.; Sojak, S.; Petriska, M.; Hinca, R.; Degmová, J.; Sabelová, V.

2012-02-01

244

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

245

Simultaneous one-dimensional fluorescence lifetime measurements of OH and CO in premixed flames  

NASA Astrophysics Data System (ADS)

A method for simultaneous measurements of fluorescence lifetimes of two species along a line is described. The experimental setup is based on picosecond laser pulses from two tunable optical parametric generator/optical parametric amplifier systems together with a streak camera. With an appropriate optical time delay between the two laser pulses, whose wavelengths are tuned to excite two different species, laser-induced fluorescence can be both detected temporally and spatially resolved by the streak camera. Hence, our method enables one-dimensional imaging of fluorescence lifetimes of two species in the same streak camera recording. The concept is demonstrated for fluorescence lifetime measurements of CO and OH in a laminar methane/air flame on a Bunsen-type burner. Measurements were taken in flames with four different equivalence ratios, namely ? = 0.9, 1.0, 1.15, and 1.25. The measured one-dimensional lifetime profiles generally agree well with lifetimes calculated from quenching cross sections found in the literature and quencher concentrations predicted by the GRI 3.0 mechanism. For OH, there is a systematic deviation of approximately 30 % between calculated and measured lifetimes. It is found that this is mainly due to the adiabatic assumption regarding the flame and uncertainty in H2O quenching cross section. This emphasizes the strength of measuring the quenching rates rather than relying on models. The measurement concept might be useful for single-shot measurements of fluorescence lifetimes of several species pairs of vital importance in combustion processes, hence allowing fluorescence signals to be corrected for quenching and ultimately yield quantitative concentration profiles.

Jonsson, Malin; Ehn, Andreas; Christensen, Moah; Aldén, Marcus; Bood, Joakim

2013-07-01

246

Charm and beauty lifetime measurements with the MARK II vertex detector  

SciTech Connect

We have measured the lifetime of the D/sup 0/ meson and the average lifetime of b-flavored hadrons with the MARK II vertex detector at PEP. We find tau/sub D/sup 0// = (4.0 +- 1.4/1.1 +- 1.0) x 10/sup -13/ sec and tau/sub b/ = (12.0 +- 4.5/3.6 +- 3.0 x 10/sup -13/ sec. 11 references.

Jaros, J.A.

1983-10-01

247

Precision Lifetime Measurement of 2{sub 1}{sup +} State in {sup 120}Te  

SciTech Connect

The lifetime of the {sup 120}Te first-excited 2{sup +} state is measured using the recoil distance Doppler shift (RDDS) method after population by inverse-kinematics Coulomb excitation. The resulting mean lifetime of 10.4(2) ps provides a factor of ten improvement in precision relative to the previously accepted value. A number of necessary corrections are discussed stemming from relativistic effects due to large recoil velocities.

Terry, J. R.; Werner, V.; Casperson, R. J.; Casten, R. F.; Heinz, A.; McCutchan, E. A.; Qian, J.; Williams, E.; Winkler, R. [Wright Nuclear Structure Lab, Yale University, New Haven CT 06520-8124 (United States); Berant, Z. [Wright Nuclear Structure Lab, Yale University, New Haven CT 06520-8124 (United States); Nuclear Research Center Negev, Beer-Sheva, 84190 Israel (Israel); Henning, G. [Wright Nuclear Structure Lab, Yale University, New Haven CT 06520-8124 (United States); Department of Physics, ENS de Cachan, 94230 Cachan (France); Luettke, R. [Wright Nuclear Structure Lab, Yale University, New Haven CT 06520-8124 (United States); Technische Universitaet Darmstadt, 63289 Darmstadt (Germany); Shoraka, B. [Wright Nuclear Structure Lab, Yale University, New Haven CT 06520-8124 (United States); Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)

2009-01-28

248

First measurement of lifetimes in the yrast band of Pd100  

Microsoft Academic Search

Lifetimes of the yrast states up to 12+ and of a negative parity 5- state in Pd100 were measured by means of the recoil distance Doppler shift technique. The experiment was performed at the Cologne FN Tandem accelerator with the Cologne Plunger using the reaction Mo92(B11,p2n) to populate excited states in Pd100. Lifetimes were determined by analyzing the transitions in

D. Radeck; A. Blazhev; M. Albers; C. Bernards; A. Dewald; C. Fransen; M. Heidemann; J. Jolie; B. Melon; D. Mücher; Th. Pissulla; W. Rother; K. O. Zell; O. Möller

2009-01-01

249

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

250

Lifetime measurement in the proton-unbound nucleus {sup 109}I  

SciTech Connect

The Recoil-Distance Doppler-shift method has been combined with Recoil-Decay Tagging for the first time to measure a lifetime in the proton-unbound nucleus {sup 109}I. The lifetime value was determined using the Differential Decay-Curve method in singles mode. The result has been compared to theoretical shell-model calculations in order to better understand the nature of unbound valence nucleons at the proton drip line.

Procter, M. G.; Lumley, N. M.; Mason, P. J. R.; Taylor, M. J. [Schuster Laboratory, University of Manchester, Manchester M13 9PL (United Kingdom); Cullen, D. M. [Schuster Laboratory, University of Manchester, Manchester M13 9PL (United Kingdom); Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland); Ruotsalainen, P.; Scholey, C.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nieminen, P.; Peura, P.; Rahkila, P.; Sandzelius, M.; Saren, J.; Sorri, J.; Uusitalo, J. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland); and others

2011-11-30

251

Measurement of the average B hadron lifetime with the CDF detector  

SciTech Connect

The authors will report on a precision measurement of the average B hadron lifetime using the 1992-1993 CDF data with the new Silicon Vertex Detector. B hadrons are partially reconstructed through the decay B {r_arrow}J/{psi}X, J/{psi}{r_arrow}{mu}{sup +}{mu}{sup {minus}}. A lifetime is extracted from a fit to the 2D decay length of the J/{psi}.

Yao, Wei-Ming [Lawrence Berkeley Lab., CA (United States)

1993-04-01

252

ATOMIC AND MOLECULAR PHYSICS: Lifetime Measurement of Cold Atoms in an Integrating Sphere  

NASA Astrophysics Data System (ADS)

We present an experimental measurement of the lifetime of the cold 87Rb atoms in an integrating sphere. The atoms are cooled by the diffuse light which is generated by the diffuse reflection of laser beams in the integrating sphere. Our result shows that the lifetime is primarily determined by the free fall of the cold 87Rb atoms, and its half-life can reach 40 ms, which is suitable for many experiments, especially for a cold atom clock.

Zhang, Wen-Zhuo; Wang, Xu-Cheng; Cheng, Hua-Dong; Xiao, Ling; Liu, Liang; Wang, Yu-Zhu

2009-08-01

253

Lifetime measurements of even and odd states in neutral terbium (Tb I)  

NASA Astrophysics Data System (ADS)

Radiative lifetimes of 7 odd and 11 even parity states of Tb I (Z = 65) have been measured by the time resolved laser induced fluorescence method (TR-LIF). Experimental data for 9 out of the 18 states are obtained for the first time. The radiative lifetimes presented in this study are in good agreement with previous TR-LIF experimental results but systematically shorter than those obtained by the delayed coincidence technique.

Malcheva, G.; Engström, L.; Lundberg, H.; Nilsson, H.; Hartman, H.; Blagoev, K.

2013-10-01

254

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.

Tr?bert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

2008-10-09

255

Systematics associated with positronium fractions as measured with variable-energy positron beams  

SciTech Connect

Positronium fraction measurements using positron beams have been utilized to extract information about the diffusion properties of positrons as well as defect concentrations in the near surface region of materials under a variety of experimental conditions. Owing to this recent interest we have undertaken to study some of the systematics and uncertainties associated with measurements of the positronium fraction, f. We restrict our discussion to determinations of f based on the peak:total ratio of counting rates for a single detector, only briefly considering alternate ways of obtaining f. We conclude with several recommendations that should be of particular interest to practitioners in the field.

Schultz, P.J.; Lynn, K.G.; Jorch, H.H.

1984-11-01

256

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.

1995-11-01

257

Design Studies for Flux and Polarization Measurements of Photons and Positrons for SLAC Proposal E166: An experiment to test polarized positron production in the FFTB (LCC-0107)  

SciTech Connect

We present results from design studies carried out to investigate measurements of the flux, spectrum and polarization of undulator photons for SLAC Proposal E166. A transmission Compton polarimeter is considered for measuring the photon circular polarization. We also present results for measuring the flux and spectrum of positrons produced by the undulator photons in an 0.5X{sub 0} Titanium target. And we present some considerations for use of a transmission Compton polarimeter to measure the circular polarization of bremsstrahlung photons emitted by the polarized positrons in a thin radiator.

Woods, M

2003-10-02

258

Generation and recombination lifetime measurement in silicon wafers using impedance spectroscopy  

NASA Astrophysics Data System (ADS)

Minority carrier lifetime in silicon wafers has been measured by applying an impedance spectroscopy technique (IST). Induced p+-p and p-n junctions were formed on both sides of the silicon wafer by thermally evaporating semitransparent metal layers of palladium and aluminium respectively. As such, no thermal treatment was given to the device, and therefore there is no diffusion of impurities inside the semiconductor and the two junctions are induced in the form of accumulation and depletion regions of charge carriers respectively. Both generation and recombination lifetimes applicable under the reverse and forward bias conditions respectively have been measured. The generation lifetime was estimated to be around 73 µs, whereas the recombination lifetime has been found to be about 11 µs. It is shown that the effective recombination lifetime is determined mainly by surface recombination velocity at the silicon-palladium interface. The effective minority carrier lifetime as measured by the microwave-detected photoconductive decay method on the same sample is 12 µs which is close to the measured recombination value by the IST. This shows that impedance spectroscopy can be used to measure effective lifetime of the wafer using an induced junction structure prior to the formation of an actual device like the solar cell. Moreover, the series resistance (Rs), diode ideality factor (n) and barrier height (Vbi) obtained from C-V (using the IST) data as well as the I-V measurement of the device show agreement with the expected device parameters. Thus, the IST can be effectively employed as a tool in extracting many relevant characteristic parameters of the material and the device.

Kumar, Sanjai; Singh, P. K.; Chilana, G. S.; Dhariwal, S. R.

2009-09-01

259

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

NASA Astrophysics Data System (ADS)

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; Siemek, Krzysztof

2013-08-01

260

Measurement of optoelectronic lifetime in imaging process of silver halide material  

NASA Astrophysics Data System (ADS)

The optoelectron lifetimes in imaging process are directly related to photographic efficiency of silver halide emulsion. The lifetime of the free electrons and shallow trapped electrons decide the sensitivity and other efficiency of silver halide emulsion. Modern emulsion technology uses the incorporation of well-defined phase boundaries in emulsion crystals to reduce the recombination rate of optoelectrons and optoholes after actinic exposure. This process leads to an enhanced photographic efficiency due to the increasing optoelectron lifetime. Microwave absorption and dielectric spectrum detection technology is a powerful tool that could quickly detect the change of dielectric function of emulsion film. This technology enables contactless measurement of the optoelectron lifetime. YAG super-fast pulse laser (355 nm, 35 ps) is used as an exposure source. Signals of the free optoelectrons and shallow trapped electrons are the decay curve versus the time. The concentration of the optoelectrons depends on the maximum concentration and decay rate constant. The reciprocal of the slop of this straight line is the lifetime of the optoelectrons. The lifetime and decay curve of the free optoelectrons and shallow trapped electrons of different emulsion samples have been measured and analyzed.

Fu, Guangsheng; Yang, Shaopeng; Li, Xiao-Wei; Hu, Xiaoyong

2001-10-01

261

Lifetime measurement of low-lying excited states in neutron-rich B and C isotopes  

SciTech Connect

Lifetime measurements of low-lying excited states in neutron-rich B and C isotopes are presented. Firstly we report on lifetime measurements of the first 2{sup +} states in {sup 16,18}C by means of the recoil-shadow method applied to a radioactive-ion beam produced at RIKEN. The observed lifetimes show suppressed collectivity of around 1 W.u. for both the isotopes. Secondly, a lifetime measurement of bound excited states in {sup 13}B with N = 8, which include the low-lying E1 state at 3.68 MeV, is discussed. The measured mean lifetime of 30(10) fs corresponds to a small E1 strength of about 1.2x10{sup -3} W.u., which makes a sharp contrast in strength to the large low-lying E1 strength observed in the neighboring isotone {sup 12}Be. Both results are discussed in terms of neutron-decoupling phenomena for low-lying E1 and E2 collective motion in neutron-rich nuclei.

Iwasaki, H. [Institut fuer Kernphysik, Universitaet zu Koeln, Koeln (Germany)

2009-01-28

262

Magnetic-field-free measurements of the total cross sections for positron scattering from neon  

NASA Astrophysics Data System (ADS)

Magnetic-field-free measurements of the absolute total cross sections (TCS) for positron-neon scattering have been performed. In the energy range of 9-15 eV, the present results are larger than those of the other groups except for the Toronto group.

Nagumo, K.; Nitta, Y.; Hoshino, M.; Tanaka, H.; Nagashima, Y.

2012-03-01

263

Non-invasive measurement of left ventricular volumes and function by gated positron emission tomography  

Microsoft Academic Search

To date cardiac positron emission tomography (PET) studies have focussed on the measurement of myocardial blood flow, metabolism and receptors while left ventricular (LV) function and dimensions have been derived from other modalities. The main drawback of this approach is the difficulty of data co-registration, which limits clinical interpretation. The aim of this study was to evaluate whether it is

Heather L. Boyd; Roger N. Gunn; Norma V. S. Marinho; Stefan P. Karwatowski; Dale L. Bailey; Durval C. Costa; Paolo G. Camici

1996-01-01

264

A Gravito-Magnetic Trap for Measuring the Neutron Lifetime using Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

There continues to be a significant discrepancy amongst the most precise measurements of the neutron lifetime. To help resolve this, the lifetime experiment at the Los Alamos Neutron Science Center (LANSCE) will use polarized ultracold neutrons (UCN) trapped by gravity in an asymmetric compound toroidal trap made of permanent magnets arranged in a high field gradient configuration called a Halbach array. Progress has been made on constructing the LANL experiment which removes marginally trapped UCN, a problematic systematic effect in previous measurements, with a compound toroid and a rippled multipole field that can quickly reduce the fraction of phase space of the trap that is quasi-bound, decreasing the probability that UCN escape or have material interactions during the lifetime measuring period.

Hickerson, Kevin

2009-10-01

265

Optimum sensitivity and two-dimensional modeling of microwave detected photoconductance decay carrier lifetime measurement  

Microsoft Academic Search

Optimization of the measurement sensitivity using closed form analytical expressions derived from an electrical equivalent circuit is carried out for microwave detected photoconductance decay system used for nondestructive carrier lifetime measurement in silicon wafers. The effect of transverse inhomogeneity in the sample conductivity on the microwave power reflection is discussed using the equivalent circuit model. The effect of lateral inhomogeneity

Moustafa Y. Ghannam; Samir F. Mahmoud; Johan F. Nijs

1997-01-01

266

Characterizing microstructural changes in ferritic steels by positron annihilation spectroscopy: Studies on modified 9Cr-1Mo steel  

NASA Astrophysics Data System (ADS)

Applicability of positron annihilation spectroscopy in probing the microstructural changes in ferritic steels has been investigated with thermal treatment studies on modified 9Cr-1Mo steel, during 300-1273 K. Positron lifetime results are compared with those of ultrasonic velocity and hardness techniques with two initial microstructural conditions i.e., normalized and tempered condition as well as only normalized condition. In first case, positron lifetime is found to be sensitive to small changes in metal carbide precipitation which could not be probed by other two techniques. In later case, positron lifetime is found to be sensitive to defect annealing until 673 K and in distinguishing the growth and coarsening of metal carbide precipitation stages during 773-1073 K. The present study suggests that by combining positron lifetime, ultrasonic velocity and hardness measurements, it is possible to distinguish distinct microstructures occurring at different stages.

Hari Babu, S.; Rajkumar, K. V.; Hussain, S.; Amarendra, G.; Sundar, C. S.; Jayakumar, T.

2013-01-01

267

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

268

Lifetime Measurement of the First Excited 2+ State in C16  

Microsoft Academic Search

The lifetime of the 21+ state in C16 has been measured with the recoil distance method using the Be9(Be9,2p) fusion-evaporation reaction at a beam energy of 40 MeV. The mean lifetime was measured to be 11.7(20) ps corresponding to a B(E2;21+-->0+) value of 4.15(73)e2fm4 [1.73(30) W.u.], consistent with other even-even closed shell nuclei. Our result does not support an interpretation

M. Wiedeking; P. Fallon; A. O. Macchiavelli; J. Gibelin; M. S. Basunia; R. M. Clark; M. Cromaz; M.-A. Deleplanque; S. Gros; H. B. Jeppesen; P. T. Lake; I.-Y. Lee; L. G. Moretto; J. Pavan; L. Phair; E. Rodriguez-Vietiez; L. A. Bernstein; D. L. Bleuel; J. T. Burke; S. R. Lesher; B. F. Lyles; N. D. Scielzo

2008-01-01

269

Lifetime measurement of the first excited 2+ state in 16C.  

PubMed

The lifetime of the 2_+(1) state in 16C has been measured with the recoil distance method using the 9Be(9Be,2p) fusion-evaporation reaction at a beam energy of 40 MeV. The mean lifetime was measured to be 11.7(20) ps corresponding to a B(E2;2_+(1)-->0+) value of 4.15(73)e_2 fm_4 [1.73(30) W.u.], consistent with other even-even closed shell nuclei. Our result does not support an interpretation for "decoupled" valence neutrons. PMID:18518099

Wiedeking, M; Fallon, P; Macchiavelli, A O; Gibelin, J; Basunia, M S; Clark, R M; Cromaz, M; Deleplanque, M-A; Gros, S; Jeppesen, H B; Lake, P T; Lee, I-Y; Moretto, L G; Pavan, J; Phair, L; Rodriguez-Vietiez, E; Bernstein, L A; Bleuel, D L; Burke, J T; Lesher, S R; Lyles, B F; Scielzo, N D

2008-04-16

270

Lifetime Measurement of the First Excited 2{sup +} State in {sup 16}C  

SciTech Connect

The lifetime of the 2{sub 1}{sup +} state in {sup 16}C has been measured with the recoil distance method using the {sup 9}Be({sup 9}Be,2p) fusion-evaporation reaction at a beam energy of 40 MeV. The mean lifetime was measured to be 11.7(20) ps corresponding to a B(E2; 2{sub 1}{sup +}{yields}0{sup +}) value of 4.15(73)e{sup 2} fm{sup 4} [1.73(30) W.u.], consistent with other even-even closed shell nuclei. Our result does not support an interpretation for ''decoupled'' valence neutrons.

Wiedeking, M.; Fallon, P.; Macchiavelli, A. O.; Gibelin, J.; Basunia, M. S.; Clark, R. M.; Cromaz, M.; Deleplanque, M.-A.; Gros, S.; Jeppesen, H. B.; Lake, P. T.; Lee, I.-Y.; Moretto, L. G.; Pavan, J.; Phair, L.; Rodriguez-Vietiez, E.; Bernstein, L. A.; Bleuel, D. L.; Burke, J. T.; Lesher, S. R. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] (and others)

2008-04-18

271

Measurement of the Bc+ meson lifetime using the decay mode Bc+ --> J/Psie+nue.  

PubMed

We present a measurement of the Bc+ meson lifetime in the decay mode Bc+ --> J/Psie+nue using the Collider Detector at Fermilab II detector at the Fermilab Tevatron Collider. From a sample of about of 360 pb(-1) of pp collisions at square root of s = 1.96 TeV, we reconstruct J/Psie+ pairs with invariant mass in the kinematically allowed range 4< M(J/Psie) < 6 GeV/c2. A fit to the decay-length distribution of 238 signal events yields a measured Bc+ meson lifetime of 0.463(-0.065)(+0.073)(stat) +/- 0.036(syst) ps. PMID:16907366

Abulencia, A; Acosta, D; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Ben Haim, E; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carlsmith, D; Carosi, R; Carron, S; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chapman, J; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Chu, P H; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Cresciolo, F; Cruz, A; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cyr, D; DaRonco, S; D'Auria, S; D'Onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'Orso, M; Delli Paoli, F; Demers, S; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Devlin, T; Dionisi, C; Dittmann, J R; DiTuro, P; Dörr, C; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Ebina, K; Efron, J; Ehlers, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garcia Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giokaris, N; Giolo, K; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, S R; Hahn, K; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hatakeyama, K; Hauser, J; Hays, C; Heijboer, A; Heinemann, B; Heinrich, J; Herndon, M; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kamon, T; Kang, J; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kobayashi, H; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kovalev, A; Kraan, A; Kraus, J; Kravchenko, I; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Liss, T M; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Maki, T; Maksimovic, P; Malde, S; Manca, G; Margaroli, F; Marginean, R; Marino, C; Martin, A; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; von der Mey, M; Miao, T; Miladinovic, N; Miles, J; Miller, R; Miller, J S; Mills, C; Milnik, M; Miquel, R; Mitra, A; Mitselmakher, G; Miyamoto, A; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Naganoma, J; Nahn, S; Nakano, I; Napier, A; Naumov, D; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Nurse, E; Ogawa, T; Oh, S H; Oh, Y D; Okusawa, T; Oldeman, R; Orava, R

2006-07-07

272

DPUNS--A Differential-Plunger For Lifetime Measurements Of Tagged Exotic/Unbound Nuclear States  

SciTech Connect

This contribution focused on research to measure the lifetimes of unbound nuclear states using a differential-plunger technique combined with recoil-proton decay tagging. The results of the first lifetime measurements of unbound states in the spherical proton emitter, {sup 109}I, were discussed along with the limits to the technique. In order to proceed further, a new differential-plunger device, DPUNS, has been designed and is currently being built at the University of Manchester. DPUNS has been optimised to work with the GREAT/RITU/TDR setup at the University of Jyvaeskylae and the status of the new device is discussed.

Cullen, D. M. [Schuster Laboratory, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL (United Kingdom)

2011-10-28

273

Measurement of the Bc+ Meson Lifetime Using the Decay Mode Bc+?J/?e+?e  

NASA Astrophysics Data System (ADS)

We present a measurement of the Bc+ meson lifetime in the decay mode Bc+?J/?e+?e using the Collider Detector at Fermilab II detector at the Fermilab Tevatron Collider. From a sample of about 360pb-1 of pp¯ collisions at s=1.96TeV, we reconstruct J/?e+ pairs with invariant mass in the kinematically allowed range 4measured Bc+ meson lifetime of 0.463(+0.073)/(-0.065)(stat)±0.036(syst)ps.

Abulencia, A.; Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; Annovi, A.; Antos, J.; Aoki, M.; Apollinari, G.; Arguin, J.-F.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Attal, A.; Azfar, F.; Azzi-Bacchetta, P.; Azzurri, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Baroiant, S.; Bartsch, V.; Bauer, G.; Bedeschi, F.; Behari, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Belloni, A.; Ben Haim, E.; Benjamin, D.; Beretvas, A.; Beringer, J.; Berry, T.; Bhatti, A.; Binkley, M.; Bisello, D.; Blair, R. E.; Blocker, C.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boisvert, V.; Bolla, G.; Bolshov, A.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brau, B.; Bromberg, C.; Brubaker, E.; Budagov, J.; Budd, H. S.; Budd, S.; Burkett, K.; Busetto, G.; Bussey, P.; Byrum, K. L.; Cabrera, S.; Campanelli, M.; Campbell, M.; Canelli, F.; Canepa, A.; Carlsmith, D.; Carosi, R.; Carron, S.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chang, S. H.; Chapman, J.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Chlebana, F.; Cho, I.; Cho, K.; Chokheli, D.; Chou, J. P.; Chu, P. H.; Chuang, S. H.; Chung, K.; Chung, W. H.; Chung, Y. S.; Ciljak, M.; Ciobanu, C. I.; Ciocci, M. A.; Clark, A.; Clark, D.; Coca, M.; Compostella, G.; Convery, M. E.; Conway, J.; Cooper, B.; Copic, K.; Cordelli, M.; Cortiana, G.; Cresciolo, F.; Cruz, A.; Cuenca Almenar, C.; Cuevas, J.; Culbertson, R.; Cyr, D.; Daronco, S.; D'Auria, S.; D'Onofrio, M.; Dagenhart, D.; de Barbaro, P.; de Cecco, S.; Deisher, A.; de Lentdecker, G.; Dell'Orso, M.; Delli Paoli, F.; Demers, S.; Demortier, L.; Deng, J.; Deninno, M.; de Pedis, D.; Derwent, P. F.; Devlin, T.; Dionisi, C.; Dittmann, J. R.; Dituro, P.; Dörr, C.; Donati, S.; Donega, M.; Dong, P.; Donini, J.; Dorigo, T.; Dube, S.; Ebina, K.; Efron, J.; Ehlers, J.; Erbacher, R.; Errede, D.; Errede, S.; Eusebi, R.; Fang, H. C.; Farrington, S.; Fedorko, I.; Fedorko, W. T.; Feild, R. G.; Feindt, M.; Fernandez, J. P.; Field, R.; Flanagan, G.; Flores-Castillo, L. R.; Foland, A.; Forrester, S.; Foster, G. W.; Franklin, M.; Freeman, J. C.; Furic, I.; Gallinaro, M.; Galyardt, J.; Garcia, J. E.; Garcia Sciveres, M.; Garfinkel, A. F.; Gay, C.; Gerberich, H.; Gerdes, D.; Giagu, S.; Giannetti, P.; Gibson, A.; Gibson, K.; Ginsburg, C.; Giokaris, N.; Giolo, K.; Giordani, M.; Giromini, P.; Giunta, M.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldschmidt, N.; Goldstein, J.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González, O.; Gorelov, I.; Goshaw, A. T.; Gotra, Y.; Goulianos, K.; Gresele, A.; Griffiths, M.; Grinstein, S.; Grosso-Pilcher, C.; Group, R. C.; Grundler, U.; Guimaraes da Costa, J.; Gunay-Unalan, Z.; Haber, C.; Hahn, S. R.; Hahn, K.; Halkiadakis, E.; Hamilton, A.; Han, B.-Y.; Han, J. Y.; Handler, R.; Happacher, F.; Hara, K.; Hare, M.; Harper, S.; Harr, R. F.; Harris, R. M.; Hatakeyama, K.; Hauser, J.; Hays, C.; Heijboer, A.; Heinemann, B.; Heinrich, J.; Herndon, M.; Hidas, D.; Hill, C. S.; Hirschbuehl, D.; Hocker, A.; Holloway, A.; Hou, S.; Houlden, M.; Hsu, S.-C.; Huffman, B. T.; Hughes, R. E.; Huston, J.; Incandela, J.; Introzzi, G.; Iori, M.; Ishizawa, Y.; Ivanov, A.; Iyutin, B.; James, E.; Jang, D.; Jayatilaka, B.; Jeans, D.; Jensen, H.; Jeon, E. J.; Jindariani, S.; Jones, M.; Joo, K. K.; Jun, S. Y.; Junk, T. R.; Kamon, T.; Kang, J.; Karchin, P. E.; Kato, Y.; Kemp, Y.; Kephart, R.; Kerzel, U.; Khotilovich, V.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kirsch, L.; Klimenko, S.; Klute, M.; Knuteson, B.; Ko, B. R.; Kobayashi, H.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Korytov, A.; Kotwal, A. V.; Kovalev, A.; Kraan, A.; Kraus, J.; Kravchenko, I.; Kreps, M.; Kroll, J.; Krumnack, N.; Kruse, M.; Krutelyov, V.; Kuhlmann, S. E.; Kusakabe, Y.; Kwang, S.; Laasanen, A. T.; Lai, S.; Lami, S.; Lammel, S.; Lancaster, M.; Lander, R. L.; Lannon, K.; Lath, A.; Latino, G.; Lazzizzera, I.; Lecompte, T.; Lee, J.; Lee, J.; Lee, Y. J.; Lee, S. W.; Lefèvre, R.; Leonardo, N.; Leone, S.; Levy, S.; Lewis, J. D.; Lin, C.; Lin, C. S.; Lindgren, M.; Lipeles, E.; Liss, T. M.; Lister, A.; Litvintsev, D. O.; Liu, T.; Lockyer, N. S.; Loginov, A.; Loreti, M.; Loverre, P.; Lu, R.-S.; Lucchesi, D.; Lujan, P.; Lukens, P.; Lungu, G.; Lyons, L.; Lys, J.; Lysak, R.; Lytken, E.; Mack, P.; MacQueen, D.; Madrak, R.; Maeshima, K.; Maki, T.; Maksimovic, P.; Malde, S.; Manca, G.; Margaroli, F.; Marginean, R.; Marino, C.; Martin, A.; Martin, V.; Martínez, M.; Maruyama, T.; Matsunaga, H.; Mattson, M. E.; Mazini, R.; Mazzanti, P.; McFarland, K. S.; McIntyre, P.; McNulty, R.; Mehta, A.; Menzemer, S.; Menzione, A.; Merkel, P.; Mesropian, C.

2006-07-01

274

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

275

Plunger lifetime measurements after Coulomb excitation at intermediate beam energies  

NASA Astrophysics Data System (ADS)

Absolute transition probabilities of the first 2+ state in 110,114Pd were remeasured using the recoil distance Doppler shift technique following projectile Coulomb excitation at intermediate beam energies for the first time. The 110Pd experiment served to check the novel technique as well as the method used for the data analysis which is based on the examination of ?-ray lineshapes. Whereas the measured B(E2) value for 110Pd agrees very well with the literature, the value obtained for 114Pd 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.; Starosta, K.; Petkov, P.; Hackstein, M.; Rother, W.; 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.; Jolie, J.; Melon, B.; Miller, D.; Moeller, V.; Norris, R. P.; Pissulla, T.; Portillo, M.; Shimbara, Y.; Stolz, A.; Vaman, C.; Voss, P.; Weisshaar, D.

2009-01-01

276

Positron annihilation in low-temperature rare gases. II. Argon and neon  

Microsoft Academic Search

Lifetime measurements of slow-positron and ortho-positronium (o-Ps) annihilation have been made in argon and neon gases at room temperature and below. The argon experiments cover the temperature range 115-300 K and the density range 0.0356-0.0726 g\\/cm3 (~= 20-40 amagat). The slow-positron spectra in argon exhibit a departure from free-positron annihilation below 200 K. The departure becomes more marked as the

K. F. Canter; L. O. Roellig

1975-01-01

277

Positron annihilation in low-temperature rare gases. II. Argon and neon  

Microsoft Academic Search

Lifetime measurements of slow-positron and ortho-positronium (o-Ps) ; annihilation were made in argon and neon gases at room temperature and below. ; The argon experiments cover the temperature range 115 to 300°K and the ; density range 0.0356 to 0.0726 g\\/cm³ (approximately equal to 20 to 40 ; amagat). The slow-positron spectra in argon exhibit a departure from free-; positron

K. F. Canter; L. O. Roellig

1975-01-01

278

Implantation profile of {sup 22}Na continuous energy spectrum positrons in silicon  

SciTech Connect

The implantation profile of positrons emitted from a continuous energy spectrum source of {sup 22}Na in close proximity to a silicon target is modeled. The primary motivation is the use of positron lifetime spectroscopy to characterize layers of defects such as those created by ion irradiation, usually deemed accessible only to techniques which utilize slow positrons. The model combines the Makhov profile, used with considerable success to describe the profile of low energy (<30 keV) monoenergetic positrons, with the well-established, universal {beta}-decay energy spectrum. The success of this approach is verified by measuring the fractions of positrons absorbed in thinned silicon samples. This verification utilizes lifetime measurements performed on silicon in a bilayer sandwich configuration with copper as a backing. The model accounts for the uncertainty in the positron backscattering at the silicon/copper interface. An optimal fit of the model to the experimental data requires that the parameter defining the mean depth of the Makhov profile (usually denoted r) is energy dependent. An example of application is provided in the form of a positron lifetime measurement of defects in silicon introduced by 1.5 MeV proton irradiation. Excellent agreement is found between the lifetime data and those obtained using a slow positron technique.

Foster, P. J.; Mascher, P.; Knights, A. P.; Coleman, P. G. [Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L7 (Canada); Department of Physics, University of Bath, Bath, BA2 7AY (United Kingdom)

2007-02-15

279

Measuring Lifetimes of Long-Lived Charged Massive Particles Stopped in LHC Detectors  

NASA Astrophysics Data System (ADS)

Long-lived charged massive particles (CHAMPs) appear in various particle physics models beyond the standard model. In this Letter, we discuss the prospects for studying the stopping and decaying events of such long-lived CHAMPs at the LHC detectors, and show that the lifetime measurement (and the study of decay products) is possible with the LHC detectors for a wide range of the lifetime O(0.1)-O(1010)sec?, by using periods of no pp collision. Even a short lifetime of order 1 sec can be measured by (i) identifying the stopping event with the on-line event filter, (ii) immediately making a beam-dump signal which stops the pp collision of the LHC, and at the same time (iii) changing the trigger menu to optimize it for the detection of a CHAMP decay in the calorimeter. Other possibilities are also discussed.

Asai, Shoji; Hamaguchi, Koichi; Shirai, Satoshi

2009-10-01

280

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

281

High current pulsed positron microprobe  

SciTech Connect

We are developing a low energy, microscopically focused, pulsed positron beam for defect analysis by positron lifetime spectroscopy to provide a new defect analysis capability at the 10{sup 10} e{sup +}s{sup -l} beam at the Lawrence Livermore National Laboratory electron linac. When completed, the pulsed positron microprobe will enable defect specific, 3-dimensional maps of defect concentrations with sub-micron resolution of defect location. By coupling these data with first principles calculations of defect specific positron lifetimes and positron implantation profiles we will both map the identity and concentration of defect distributions.

Howell, R.H.; Stoeffl, W.; Kumar, A.; Sterne, P.A.; Cowan, T.E.; Hartley, J.

1997-05-01

282

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

283

Fluorine18 deoxyglucose uptake in sarcoidosis measured with positron emission tomography  

Microsoft Academic Search

Regional pulmonary glucose metabolism (MRglu; µmol h-1 g-1), extravascular lung density (DEV; g cm-3) and vascular volume (VB; ml cm-3) were measured in a single midthoracic transaxial slice (˜2 cm thick) using positron emission tomography (PET) in seven patients with histologically proven sarcoidosis. The measurements were repeated 1–7 months later after steroid therapy (in two cases, no treatment) in order

Lars H. Brudin; Sven-Olof Valind; Christopher G. Rhodes; Charles F. Panting; Martin Sweatmang; Terry Jones; J. M. B. Hughes

1994-01-01

284

First measurement of lifetimes in the yrast band of Pd100  

NASA Astrophysics Data System (ADS)

Lifetimes of the yrast states up to 12+ and of a negative parity 5- state in Pd100 were measured by means of the recoil distance Doppler shift technique. The experiment was performed at the Cologne FN Tandem accelerator with the Cologne Plunger using the reaction Mo92(B11,p2n) to populate excited states in Pd100. Lifetimes were determined by analyzing the transitions in coincidence mode employing the differential decay curve method. The obtained E2 transition strengths were compared to predictions from collective models and the shell model.

Radeck, D.; Blazhev, A.; Albers, M.; Bernards, C.; Dewald, A.; Fransen, C.; Heidemann, M.; Jolie, J.; Melon, B.; Mücher, D.; Pissulla, Th.; Rother, W.; Zell, K. O.; Möller, O.

2009-10-01

285

Measurement of the lifetime of rubidium atoms in a dark magneto-optical trap  

SciTech Connect

The lifetimes of rubidium atoms in a dark magneto-optical trap are measured at different populations of the 'bright' and 'dark' hyperfine states of captured atoms. It is found that the lifetime of atoms in the trap decreases if they spend more time in the bright state. A simple explanation of this effect is proposed which is based on the increase in the transport cross section for collisions of thermal rubidium atoms surrounding the trap with cold rubidium atoms upon their electronic excitation. (laser cooling)

Permyakova, O I; Yakovlev, A V; Chapovskii, P L [Institute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation)

2008-09-30

286

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

287

First measurement of lifetimes in the yrast band of {sup 100}Pd  

SciTech Connect

Lifetimes of the yrast states up to 12{sup +} and of a negative parity 5{sup -} state in {sup 100}Pd were measured by means of the recoil distance Doppler shift technique. The experiment was performed at the Cologne FN Tandem accelerator with the Cologne Plunger using the reaction {sup 92}Mo({sup 11}B,p2n) to populate excited states in {sup 100}Pd. Lifetimes were determined by analyzing the transitions in coincidence mode employing the differential decay curve method. The obtained E2 transition strengths were compared to predictions from collective models and the shell model.

Radeck, D.; Blazhev, A.; Albers, M.; Bernards, C.; Dewald, A.; Fransen, C.; Heidemann, M.; Jolie, J.; Melon, B.; Muecher, D.; Pissulla, Th.; Rother, W.; Zell, K. O.; Moeller, O. [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln (Germany); Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstr. 9, D-64289 Darmstadt (Germany)

2009-10-15

288

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

289

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

290

DSA lifetime measurements and structure of positive-parity bands of 120Xe  

NASA Astrophysics Data System (ADS)

Lifetimes of excited states in 120Xe have been measured by the Doppler-shift attenuation method in the 111Cd( 12C,3n) reaction at a beam energy of E = 56 MeV. Lifetime values for 22 states were obtained. The excitation energies and E2-transition probabilities of the yrast band, ?-band and its continuation are interpreted in the framework of a version of IBFM (IBM + 2 q.p.). A reasonable description of the B(E2) behavior in the backbending region is achieved.

Pasternak, A. A.; Sasaki, Y.; Efimov, A. D.; Mikhajlov, V. M.; Hayakawa, T.; Toh, Y.; Oshima, M.; Hatsukawa, Y.; Katakura, J.; Shinohara, N.; Liu, Z.; Furuno, K.

291

Combinatorial fluorescence lifetime measuring system for developing Er-doped transparent glass ceramics  

Microsoft Academic Search

Fluorescence lifetime of Er3+ was measured for F-doped tellurite glasses with parallel heat treatment under a temperature gradient atmosphere in order to find the annealing condition to make transparent glass ceramics in which Er3+ ions are located in the precipitated crystals. The preparation and annealing of the samples were performed in a vertical temperature gradient furnace, where molten glass was

S. Todoroki; S. Inoue

2004-01-01

292

Fluorescence-lifetime measurements in monodispersed suspensions of polystyrene particles: Comment  

NASA Astrophysics Data System (ADS)

This paper discusses the results and observations published in another paper with respect to fluorescence-lifetime measurements on other similar systems. The effect of photon diffusion in the estimation of radiation rate by techniques using emitted photon detection methods is discussed.

Lawandy, N. M.

1993-11-01

293

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

294

A High Throughput Approach to Measuring Carrier Mobility and Lifetime of Thin Film Semiconductors  

NASA Astrophysics Data System (ADS)

A new technique has been developed to measure the carrier mobility and lifetime based on current transients produced by a sub-picosecond laser pulse. The theoretical model we proposed agrees well with the experimental data. This technique has been applied to the material libraries fabricated by the combinatorial growth technique.

Mao, S. S.; Ma, Z. X.; Oehlerking, L. J.; Chen, Z. Y.; Yu, P. Y.

2011-12-01

295

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

296

Improved measurement of the $\\\\overline{B}^{0}$ and B$^{-}$ meson lifetimes  

Microsoft Academic Search

The lifetimes of the \\\\b0 \\\\ and \\\\bp\\\\ 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 \\\\b0 \\\\ and \\\\bp\\\\ mesons were partially reconstructed by identifying events containing a lepton with an associated \\\\ds\\\\ or \\\\d0 \\\\

Damir Buskulic; I De Bonis; D Décamp; 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 C Delfino; I Efthymiopoulos; E Fernández; M Fernández-Bosman; L Garrido; A Juste; M Martínez; S Orteu; A Pacheco; C Padilla; A Pascual; J A Perlas; I Riu; F Sánchez; F Teubert; A Colaleo; D Creanza; M De Palma; G Gelao; M Girone; Giuseppe 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; Roger W Forty; M Frank; R Hagelberg; J Harvey; P Janot; B Jost; E Kneringer; J Knobloch; Ivan Lehraus; E B Martin; P Mato; Adolf G Minten; R Miquel; L M Mir; L Moneta; T Oest; Fabrizio Palla; J R Pater; J F Pusztaszeri; F Ranjard; P E Rensing; Luigi Rolandi; W D Schlatter; M Schmelling; O Schneider; W Tejessy; I R Tomalin; A Venturi; H W Wachsmuth; A Wagner; T Wildish; Ziad J 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; Tom Fearnley; J B Hansen; J D Hansen; J R Hansen; P H Hansen; B S Nilsson; A Wäänänen; A Kyriakis; C Markou; Errietta Simopoulou; I Siotis; Anna Vayaki; K Zachariadou; A Blondel; G R Bonneaud; J C Brient; P Bourdon; A Rougé; M Rumpf; Andrea Valassi; M Verderi; H L Videau; D J Candlin; M I Parsons; E Focardi; G Parrini; M Corden; C H Georgiopoulos; D E Jaffe; A Antonelli; G Bencivenni; G Bologna; F Bossi; P Campana; G Capon; David William Casper; V Chiarella; G Felici; P Laurelli; G Mannocchi; F Murtas; G P Murtas; L Passalacqua; M Pepé-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; David M Binnie; W Cameron; Peter 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; Terence 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; Jean-Jacques Aubert; A M Bencheikh; C Benchouk; A Bonissent; G Bujosa; D Calvet; J Carr; C A Diaconu; F Etienne; N P Konstantinidis; P Payre; D Rousseau; M Talby; A Sadouki; M Thulasidas; K Trabelsi; M Aleppo; F Ragusa; I Abt; R W Assmann; C Bauer; Walter Blum; 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; W Wiedenmann; G Wolf; J Boucrot; O Callot; A Cordier; M Davier; L Duflot; J F Grivaz; P Heusse; M Jacquet; D W Kim; F R Le Diberder; J Lefrançois; A M Lutz; I A 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; Jack Steinberger; Roberto 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-Töller; David 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; 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; 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 L Cartwright; F Combley; A Köksal; M Letho; W M Newton; J Reeve; L F Thompson; A Böhrer; S Brandt; V Büscher; G D Cowan; 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; G Musolino; J E Rothberg; S R 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; M Schmitt; I J Scott; V Sharma; A M Walsh; Wu Sau Lan; X Wu; J M Yamartino; M Zheng; G Zobernig

1996-01-01

297

Bulk lifetime and surface recombination velocity measurement method in semiconductor wafers  

Microsoft Academic Search

A noncontact and nondestructive measurement method is proposed to separately determine the bulk lifetime ?b, and the front and backsurface recombination velocities S0 and Sw in the semiconductor wafer with different surface recombination velocities in the front and backsurfaces. The method is deduced based on a new analytical solution for photoconductivity decays derived for the wafer with different surface recombination

Yoh-Ichiro Ogita

1996-01-01

298

Direct Measurement of the Radiative Lifetime of Vibrationally Excited OH Radicals  

Microsoft Academic Search

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

Sebastiaan Y. van de Meerakker; Nicolas Vanhaecke; Mark P. van der Loo; Gerrit C. Groenenboom; Gerard Meijer

2005-01-01

299

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

300

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

301

Measurement of upper level lifetime in presence of radiation trapping: A revisitation of the pinhole method  

NASA Astrophysics Data System (ADS)

In this work we expose a recently developed theoretical model for the analysis of the measurements obtained with the so-called pinhole method, for the determination of the upper level lifetime in materials where the superimposition between fluorescence and absorption spectra determines significant radiation trapping effect. Under fairly general conditions the fluorescence decay curve after a pulsed excitation of the sample obtained with this experimental set-up can be conveniently described by a double exponential functional form. The faster of the two decay times is close to the intrinsic fluorescence lifetime, with a difference that can be calculated with geometrical considerations. The theoretical results were tested with a suitably designed experiment, where the upper level lifetime of the laser transition of some Yb doped samples were investigated, obtaining results that are consistent with literature data and in good agreement with the theoretical results as for the temporal dependence of the fluorescence decay.

Toci, G.; Pirri, A.; Alderighi, D.; Vannini, M.

2012-12-01

302

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

303

Non-invasive evaluation of dermal elastosis by in vivo multiphoton tomography with autofluorescence lifetime measurements.  

PubMed

The non-invasive differentiation of dermal elastic fibres from solar elastosis in vivo is of great interest in dermatologic research, especially for efficacy testing of anti-ageing products. To date, no studies on multiphoton excited fluorescence lifetime characteristics of human elastic fibres and solar elastosis are reported. The goal of the present work was the identification of differential criteria for elastic fibres and solar elastosis by the analysis of fluorescence decay curves acquired by time-correlated single photon counting in vivo multiphoton tomography. For this purpose, fluorescence lifetime measurements (FLIM) were performed with 47 volunteers of different age groups at sun-protected and sun-exposed localizations. Bi-exponential curve fitting was applied to the FLIM data, and characteristic differences between age groups and localizations were found in both relevant fit parameters describing the decay slope. The FLIM analyses have shown that dermal autofluorescence has different lifetimes depending on age and in part on localization. PMID:22151391

Koehler, Martin J; Preller, Anja; Elsner, Peter; König, Karsten; Hipler, Uta C; Kaatz, Martin

2012-01-01

304

Effect of free volume and temperature on the structural relaxation in polymethylphenylsiloxane: a positron lifetime and pressure-volume-temperature study.  

PubMed

The microstructure of the free volume and its temperature dependence in polymethylphenylsiloxane (PMPS) have been examined using positron annihilation lifetime spectroscopy (PALS) and pressure-volume-temperature experiments. The hole-free volume fraction h and the specific hole-free and occupied volumes, Vf=hV and Vocc=(1-h)V, were estimated employing the Simha-Somcynsky (SS) lattice-hole theory. From the PALS spectra analyzed with the new routine LT9.0 the hole size distribution, its mean, , and mean dispersion, sigmah, were calculated. A comparison of with V and Vf delivered a constant specific hole number Nh'. Using a fluctuation approach the temperature dependency of the volume of the smallest representative freely fluctuating subsystem, , is estimated to vary from approximately 8.5 nm3 at Tg to approximately 3 nm3 at T/Tg>or=1.15. Unlike other polymers, the segmental relaxation from dielectric spectroscopy of PMPS follows the Cohen-Turnbull free volume theory almost perfectly in the temperature and pressure ranges between 243 and 279 K and 0 and approximately 100 MPa. This behavior correlates with the small mass of the SS lattice mer which indicates the high flexibility of the PMPS chain. Above 293 K and approximately 150 MPa, the free volume prediction gives relaxation times that are too small, which indicates that effects of thermal energy must be included in the analysis. To quantify the degree to which volume and thermal energy govern the structural dynamics the ratio of the activation enthalpies, Ei=R[(d ln taudT1)]i (tau-relaxation time of alpha relaxation), at constant volume V and constant pressure P, EV/EP, is frequently determined. The authors present arguments for necessity to substitute EV with EVf, the activation enthalpy at constant (hole) free volume, and show that EVf/EP changes as expected: increasing with increasing free volume, i.e., with increasing temperature and decreasing pressure. EVf/EP (=0.04-0.1) exhibits remarkably smaller values than EV/EP (=0.44-0.53), which leads to the inference that the free volume plays a distinctly larger role in dynamics than traditionally concluded from EV/EP. This conclusion is in agreement with the results of our more direct Cohen-Turnbull free volume analysis. PMID:17228972

Dlubek, G; Shaikh, M Q; Krause-Rehberg, R; Paluch, M

2007-01-14

305

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

NASA Astrophysics Data System (ADS)

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+ states in the neutron-rich 62,64,66Fe 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 66Fe 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

2013-04-01

306

Effect on radiation trapping on measured excited-state lifetimes in solids  

SciTech Connect

A refractive index matched experimental setup that largely eliminates the effects of radiation trapping on measured excited-state lifetimes in high refractive index solids is presented. An index-matched glass sphere was used to measure the room-temperature lifetimes of {sup 2}F{sub 5/2} in YAG:l%Yb{sup 3+} and {sup 4}I{sub 1/2} in YLF:5%Er{sup 3+}, yielding the record low values of 948.9{plus_minus}0.6 {mu}s and 3.85{plus_minus}0.01 ms, respectively. It is concluded that lifetimes from non index-matched experiments are most likely to be significantly over estimated in high refractive-index solids for excited states with a large radiative component to the ground-state multiplet and a high reabsorption cross section. The presented technique is easily applicable to room-temperature excited-state lifetime measurements of many luminescent solids.

Hehlen, M.P.

1996-04-01

307

Bulk carrier lifetime measurement by the microwave reflectance photoconductivity decay method with external surface electric field  

NASA Astrophysics Data System (ADS)

We attempted to measure the bulk carrier recombination lifetime of Si wafers by the microwave reflectance photoconductivity decay (PCD) method. Voltage was applied between an external electrode and a Si wafer to suppress surface recombination. Before the measurement, the surface state density was reduced by a chemical treatment using NH4OH-H2O2-H2O and diluted HF solutions. Carrier lifetime as long as 1 ms was measured by the present method for a wafer with a bare surface. Comparison with results for oxidized wafers show that the present method can suppress surface recombination more effectively than thermal oxidation, which has been often used for surface passivation in PCD measurements.

Ichimura, Masaya; Tada, Atsushi; Arai, Eisuke; Takamatsu, Hiroyuki; Sumie, Shingo

2002-06-01

308

Measuring W Photon Couplings in a 500 GEV Positron - Collider  

NASA Astrophysics Data System (ADS)

The Standard Model gives definite predictions for the W-photon couplings. Measuring them would test an important ingredient of the model. In this work we study the capability of a 500 GeV e^+e^ - collider to measure these couplings. We study the most general C and P conserving WWgamma vertex. This vertex contains two free parameters, kappa and lambda. We look at three processes: e ^+e^-to W^+W^-, egammato Wnu and gammagammato W^+W^-. For each process we present analytical expressions of helicity amplitudes for arbitrary values of kappa and lambda.. We consider three different sources for the initial photon(s). The first two are breamsstrahlung and beamstrahlung (photon radiation induced by the collective fields of the opposite bunch). Both occur naturally in the collider environment. The third is a photon beam generated by scattering low energy laser light off a high energy electron beam. We examine potential observables for each process, calculating their sensitivity to kappa and lambda, and estimating the accuracy with which they can be measured. Assuming Standard Model values are actually measured, we present the region in the kappa-lambda plane to which the W couplings can be restricted with a given confidence level. We find that combining the three processes, one can measure kappa and lambda with accuracy of 0.01 -0.02.

Yehudai, Eran

309

Measurement of the B⁻ and {bar B}° meson lifetimes using semileptonic decays  

Microsoft Academic Search

The lifetimes of the B⁻ and {bar B}° mesons are measured using the partially reconstructed semileptonic decays {bar B}âDl⁻{bar ν}X, where D is either a D° or D{sup *+} meson. The data were collected by the CDF detector at the Fermilab Tevatron collider during 1992â1995 and correspond to about 110thinsppb⁻¹ of {bar p}p collisions at â (s) =1.8thinspTeV. We measure

R. E. Blair; K. L. Byrum; E. Kovacs; S. E. Kuhlmann; T. LeCompte; L. Nodulman; L. Breccia; R. Brunetti; M. Deninno; I. Fiori; P. Mazzanti; S. Behrends; J. Bensinger; C. Blocker; L. Kirsch; J. I. Lamoureux; Y. Bonushkin; J. Hauser; M. Lindgren; A. Amadon; J. Berryhill; M. Contreras; R. Culbertson; C. Grosso-Pilcher; M. Hohlmann; D. Cronin-Hennessy; J. R. Dittmann; A. T. Goshaw; D. Khazins; W. Kowald; S. H. Oh; M. G. Albrow; M. Atac; A. Beretvas; J. P. Berge; K. Biery; M. Binkley; E. Buckley-Geer; A. Byon-Wagner; F. Chlebana; S. Cihangir; J. Cooper; F. DeJongh; R. Demina; P. F. Derwent; J. E. Elias; W. Erdmann; B. Flaugher; G. W. Foster; J. Freeman; S. Geer; S. R. Hahn; R. M. Harris; J. Incandela; H. Jensen; U. Joshi; R. D. Kennedy; R. Kephart; S. Lammel; J. D. Lewis; P. Limon; P. Lukens; K. Maeshima; J. P. Marriner; T. Miao; A. Mukherjee; C. Nelson; C. Newman-Holmes; J. Patrick; S. Klimenko; J. Konigsberg; A. Korytov; A. Nomerotski; M. Barone; S. Bertolucci; M. Cordelli; S. DellAgnello; P. Giromini; F. Happacher; S. Miscetti; A. Parri; A. G. Clark; C. Couyoumtzelis; H. Kambara; T. Baumann; M. Franklin; A. Gordon; J. Huth; D. Kestenbaum

1998-01-01

310

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

311

Excess carrier lifetime of 3C-SiC measured by the microwave photoconductivity decay method  

Microsoft Academic Search

Excess carrier lifetime of 3C–SiC grown on a Si substrate by chemical vapor deposition is measured at room temperature by the noncontact microwave photoconductivity decay method. A N2 laser is used to excite carriers in the SiC layer. The measured decay curves of the excess carrier concentration have fast (? ≈3 ?s) and slow (? >200 ?s) components. The origin

M. Ichimura; H. Tajiri; Y. Morita; N. Yamada; A. Usami

1997-01-01

312

CMOS direct time interval measurement of long-lived luminescence lifetimes.  

PubMed

We describe a Complementary Metal-Oxide Semiconductor (CMOS) Direct Time Interval Measurement (DTIM) Integrated Circuit (IC) to detect the decay (fall) time of the luminescence emission when analyte-sensitive luminophores are excited with an optical pulse. The CMOS DTIM IC includes 14 × 14 phototransistor array, transimpedance amplifier, regulated gain amplifier, fall time detector, and time-to-digital convertor. We examined the DTIM system to measure the emission lifetime of oxygen-sensitive luminophores tris(4,7-diphenyl-1, 10-phenanthroline) ruthenium(II) ([Ru(dpp)(3)](2+)) encapsulated in sol-gel derived xerogel thin-films. The DTIM system fabricated using TSMC 0.35 ?m process functions to detect lifetimes from 4 ?s to 14.4 ?s but can be tuned to detect longer lifetimes. The system provides 8-bit digital output proportional to lifetimes and consumes 4.5 mW of power with 3.3 V DC supply. The CMOS system provides a useful platform for the development of reliable, robust, and miniaturized optical chemical sensors. PMID:22254237

Yao, Lei; Yung, Ka Yi; Cheung, Maurice C; Chodavarapu, Vamsy P; Bright, Frank V

2011-01-01

313

Study of the Mg-Cd system by positron annihilation methods  

NASA Astrophysics Data System (ADS)

The problem of preferential positron annihilation in binary alloys has not been satisfactorily solved in the past. We examine this effect experimentally in Mg-Cd alloys using the new technique of Doppler broadening measurements with background reduction which allows us to observe positron annihilation with core electrons. Conventional positron lifetime spectroscopy is applied as well. We measure the Doppler spectra and positron lifetimes for selected alloys in the whole concentration range of the Mg-Cd system. The analysis of experimental results is supported by theoretical calculations. The conclusion is given that a small positron preferential annihilation occurs at Mg sites. Besides, the temperature dependencies of the peak counting rate of the angular correlation curve are measured for several samples and the vacancy formation energies are established. In the case of Mg-20 at.% Cd alloy, the increase of the peak counting rate characteristic for generation of thermal vacancies shows a discontinuity close to the order-disorder transition temperature.

Dryzek, E.; Kuriplach, J.; Dryzek, J.

1998-07-01

314

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

315

Multiple bunch longitudinal dynamics measurements at the Cornell Electron-Positron Storage Ring  

Microsoft Academic Search

The Cornell Electron-Positron Storage Ring (CESR) has a longitudinal dipole-coupled-bunch instability that limits the total amount of current that can be stored in the ring without feedback. As a result, it is one of the major limitations for higher stored current and luminosity. This paper reports the measurements of multiple bunch longitudinal dynamics done on CESR with a streak camera.

R. Holtzapple; M. Billing; D. Hartill

2001-01-01

316

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

317

First measurement of charged current cross sections at HERA with longitudinally polarised positrons  

Microsoft Academic Search

Data taken with positrons of different longitudinal polarisation states in collision with unpolarised protons at HERA are used to measure the total cross sections of the charged current process, e+p??¯X, for negative four-momentum transfer squared Q2>400 GeV2 and inelasticity y0.9. Together with the corresponding cross section obtained from the previously published unpolarised data, the polarisation dependence of the charged current cross

A. Aktas; V. Andreev; T. Anthonis; B. Antunovic; S. Aplin; A. Asmone; A. Astvatsatourov; A. Babaev; S. Backovic; J. Bähr; A. Baghdasaryan; P. Baranov; E. Barrelet; W. Bartel; S. Baudrand; S. Baumgartner; J. Becker; M. Beckingham; O. Behnke; O. Behrendt; A. Belousov; Ch. Berger; N. Berger; J. C. Bizot; M.-O. Boenig; V. Boudry; J. Bracinik; G. Brandt; V. Brisson; D. Bruncko; F. W. Büsser; A. Bunyatyan; G. Buschhorn; L. Bystritskaya; A. J. Campbell; F. Cassol-Brunner; K. Cerny; V. Cerny; V. Chekelian; J. G. Contreras; J. A. Coughlan; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; W. D. Dau; K. Daum; Y. de Boer; B. Delcourt; M. Del Degan; A. De Roeck; K. Desch; E. A. De Wolf; C. Diaconu; V. Dodonov; A. Dubak; G. Eckerlin; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Elsen; W. Erdmann; S. Essenov; A. Falkewicz; P. J. W. Faulkner; L. Favart; A. Fedotov; J. Feltesse; L. Finke; M. Fleischer; P. Fleischmann; G. Flucke; A. Fomenko; I. Foresti; G. Franke; T. Frisson; E. Gabathuler; J. Gayler; C. Gerlich; S. Ghazaryan; S. Ginzburgskaya; A. Glazov; I. Glushkov; L. Goerlich; M. Goettlich; N. Gogitidze; S. Gorbounov; C. Goyon; T. Greenshaw; M. Gregori; B. R. Grell; G. Grindhammer; C. Gwilliam; D. Haidt; L. Hajduk; M. Hansson; G. Heinzelmann; R. C. W. Henderson; H. Henschel; G. Herrera; M. Hildebrandt; K. H. Hiller; D. Hoffmann; R. Horisberger; A. Hovhannisyan; T. Hreus; S. Hussain; M. Ibbotson; M. Jacquet; L. Janauschek; X. Janssen; V. Jemanov; L. Jönsson; D. P. Johnson; A. W. Jung; H. Jung; M. Kapichine; J. Katzy; I. R. Kenyon; C. Kiesling; M. Klein; C. Kleinwort; T. Klimkovich; G. Knies; A. Knutsson; V. Korbel; P. Kostka; K. Krastev; J. Kretzschmar; A. Kropivnitskaya; K. Krüger; J. Kückens; M. P. J. Landon; W. Lange; T. Laštovi?ka; G. Laštovi?ka-Medin; P. Laycock; A. Lebedev; G. Leibenguth; V. Lendermann; S. Levonian; L. Lindfeld; K. Lipka; A. Liptaj; B. List; J. List; E. Lobodzinska; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A.-I. Lucaci-Timoce; H. Lueders; D. Lüke; T. Lux; L. Lytkin; A. Makankine; N. Malden; E. Malinovski; S. Mangano; P. Marage; R. Marshall; M. Martisikova; H.-U. Martyn; S. J. Maxfield; D. Meer; A. Mehta; K. Meier; A. B. Meyer; H. Meyer; J. Meyer; V. Michels; S. Mikocki; I. Milcewicz-Mika; D. Milstead; A. Mohamed; F. Moreau; A. Morozov; J. V. Morris; M. U. Mozer; K. Müller; P. Murín; K. Nankov; B. Naroska; Th. Naumann; P. R. Newman; C. Niebuhr; A. Nikiforov; G. Nowak; M. Nozicka; R. Oganezov; B. Olivier; J. E. Olsson; S. Osman; D. Ozerov; V. Palichik; I. Panagoulias; T. Papadopoulou; C. Pascaud; G. D. Patel; H. Peng; E. Perez; D. Perez-Astudillo; A. Perieanu; A. Petrukhin; D. Pitzl; R. Pla?akyt?; B. Portheault; P. Prideaux; A. J. Rahmat; N. Raicevic; P. Reimer; B. Reisert; A. Rimmer; C. Risler; E. Rizvi; P. Robmann; B. Roland; R. Roosen; A. Rostovtsev; Z. Rurikova; S. Rusakov; F. Salvaire; D. P. C. Sankey; E. Sauvan; S. Schätzel; S. Schmidt; C. Schmitz; L. Schoeffel; A. Schöning; H.-C. Schultz-Coulon; K. Sedlák; F. Sefkow; R. N. Shaw-West; I. Sheviakov; L. N. Shtarkov; T. Sloan; P. Smirnov; Y. Soloviev; D. South; V. Spaskov; A. Specka; M. Steder; B. Stella; J. Stiewe; I. Strauch; U. Straumann; D. Sunar; V. Tchoulakov; G. Thompson; P. D. Thompson; F. Tomasz; D. Traynor; P. Truöl; I. Tsakov; G. Tsipolitis; I. Tsurin; J. Turnau; E. Tzamariudaki; K. Urban; M. Urban; A. Usik; D. Utkin; A. Valkárová; C. Vallée; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; C. Veelken; S. Vinokurova; V. Volchinski; K. Wacker; J. Wagner; G. Weber; R. Weber; D. Wegener; C. Werner; M. Wessels; B. Wessling; C. Wigmore; Ch. Wissing; R. Wolf; E. Wünsch; S. Xella; W. Yan; V. Yeganov; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhelezov; Y. C. Zhu; J. Zimmermann; T. Zimmermann; H. Zohrabyan; F. Zomer

2006-01-01

318

Measurement of excited-state lifetime using two-pulse photon echoes in rubidium vapor  

SciTech Connect

We report a measurement of the 5P{sub 3/2} excited-state lifetime using two-pulse photon echoes in Rb vapor. The measurement is precise to {approx}1% and agrees with the best measurement of atomic lifetime in Rb. The results suggest that a measurement precise to {approx}0.25% is possible through additional data acquisition and study of systematic effects. The experiment relies on short optical pulses generated from a cw laser using acousto-optic modulators. The excitation pulses are on resonance with the F=3{yields}F{sup '}=4 transition in {sup 85}Rb or the F=2{yields}F{sup '}=3 transition in {sup 87}Rb. The resulting photon echo signal is detected using a heterodyne detection technique. The excited-state lifetime is determined by measuring the exponential decay of the echo intensity as a function of the time between the excitation pulses. We also present a study of the echo intensity as a function of excitation pulse area and compare the results to simulations based on optical Bloch equations. The simulations include the effects of spontaneous emission as well as spatial and temporal variations of the intensities of excitation pulses.

Rotberg, E. A.; Barrett, B.; Beattie, S.; Chudasama, S.; Weel, M.; Chan, I.; Kumarakrishnan, A. [Department of Physics and Astronomy, York University, Toronto Ontario M3J 1P3 (Canada)

2007-03-15

319

Measuring electron-positron annihilation radiation from laser plasma interactions  

SciTech Connect

We investigated various diagnostic techniques to measure the 511 keV annihilation radiations. These include step-wedge filters, transmission crystal spectroscopy, single-hit CCD detectors, and streaked scintillating detection. While none of the diagnostics recorded conclusive results, the step-wedge filter that is sensitive to the energy range between 100 keV and 700 keV shows a signal around 500 keV that is clearly departing from a pure Bremsstrahlung spectrum and that we ascribe to annihilation radiation.

Chen, Hui; Tommasini, R. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Seely, J.; Szabo, C. I.; Feldman, U.; Pereira, N. [Artep Inc., Ellicott City, Maryland 21042 (United States); Gregori, G.; Falk, K.; Mithen, J.; Murphy, C. D. [Clarendon Laboratory, University of Oxford, Oxford OX1 3PU (United Kingdom)

2012-10-15

320

Determination of the singlet state lifetime of dissolved nitrous oxide from high field relaxation measurements  

PubMed Central

Longitudinal spin relaxation due to modulation of dipolar interactions often limits the development of hyperpolarized magnetic tracers. Recently, it has been demonstrated that transferring spin order to a singlet state significantly increases the polarization lifetimes in systems where nitrous oxide is dissolved in a liquid solvent. Additionally, previous studies have suggested that the longitudinal relaxation of nitrous oxide is largely dominated by the spin-rotation interaction. Models of spin-relaxation under Brownian motion naïvely predict the angular momentum reorienting correlation time of the spin rotation interaction to be inversely proportional to the viscosity of the solution. This dependence implies the singlet lifetime can be lengthened by increasing the dissolving solvent's viscosity—an extension which is not observed. Our work formulates a model which describes the relaxation of nitrous oxide dissolved in various solvents. We investigate the effect of altering the temperature of the solvent, as well as the effect of varying solute-solvent interactions on the singlet state as well as the longitudinal polarization lifetime. We predict the singlet lifetime for nitrous oxide dissolved in several solvents by fitting rotational and angular momentum correlation times measured at high magnetic field, and relate singlet relaxation to translational diffusion constants.

Ghosh, Rajat K.; Kadlecek, Stephen J.; Kuzma, Nicholas N.; Rizi, Rahim R.

2012-01-01

321

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

322

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

323

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

324

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

325

Lifetime measurements using the CLARA-PRISMA setup around the {sup 48}Ca doubly-magic nucleus  

SciTech Connect

The lifetimes of the first excited states of nuclei around the doubly-magic nucleus {sup 48}Ca have been determined using a novel method that combines the Recoil Distance Doppler Shift (RDDS) method with the CLARA-PRISMA spectrometers. This is the first time such a method is applied to measure lifetimes of neutron-rich nuclei populated via a multinucleon transfer reaction. This novel method and some preliminary results on lifetimes are presented.

Valiente-Dobon, J. J.; Gadea, A.; Stefanini, A. M.; Corradi, L.; De Angelis, G.; Fioretto, E.; Grodner, E.; Mason, P.; Napoli, D. R.; Recchia, F.; Sahin, E. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Mengoni, D. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Dipartimento di fisica dell'Universita and INFN sezione di Padova, Padova (Italy); Farnea, E.; Bazzacco, D.; Montagnoli, G.; Ur, C. A. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Lenzi, S. M.; Lunardi, S.; Scarlassara, F. [Dipartimento di fisica dell'Universita and INFN sezione di Padova, Padova (Italy); Dewald, A. [Institut fuer Kernphysik der Universtaet zu Koeln, Koeln (Germany)] (and others)

2008-11-11

326

Precision Measurements of Atomic Lifetimes and Hyperfine Energies in Alkali Like Systems  

SciTech Connect

Financial support of this research project has lead to advances in the study of atomic structure through precision measurements of atomic lifetimes, energy splittings, and transitions energies. The interpretation of data from many areas of physics and chemistry requires an accurate understanding of atomic structure. For example, scientists in the fields of astrophysics, geophysics, and plasma fusion depend on transition strengths to determine the relative abundances of elements. Assessing the operation of discharges and atomic resonance line filters also depends on accurate knowledge of transition strengths. Often relative transition strengths are measured precisely, but accurate atomic lifetimes are needed to obtain absolute values. Precision measurements of atomic lifetimes and energy splittings also provide fundamentally important atomic structure information. Lifetimes of allowed transitions depend most strongly on the electronic wave function far from the nucleus. Alternatively, hyperfine splittings give important information about the electronic wave function in the vicinity of the nucleus as well as the structure of the nucleus. Our main focus throughout this project has been the structure of atomic cesium because of its connection to the study of atomic parity nonconservation (PNC). The interpretation of atomic PNC experiments in terms of weak interaction coupling constants requires accurate knowledge of the electronic wave function near the nucleus as well as far from the nucleus. It is possible to address some of these needs theoretically with sophisticated many-electron atomic structure calculations. However, this program has been able to address these needs experimentally with a precision that surpasses current theoretical accuracy. Our measurements also play the important role of providing a means for testing the accuracy of many-electron calculations and guiding further theoretical development, Atomic systems such as cesium, with a single electron outside of a closed shell, provide the simplest open shell systems for detailed comparisons between experiment and theory. This program initially focused on measurements of excited state atomic lifetimes in alkali atomic systems. Our first measurements of atomic lifetimes in cesium surpassed the precision and accuracy of previous measurements and sparked renewed interest in the need for greater precision in lifetime measurements throughout the atomic physics community. After enhancing the capabilities of the laser systems built for these initial measurements, we began a study hyperfine energy splittings in cesium using a thermal atomic beam. The results surpassed previous measurements by more than an order of magnitude and lead to the first observation of the nuclear magnetic octupole moment in cesium demonstrating the inadequacy of the nuclear shell model for predicting high order nuclear moments. The laser system and atomic beam apparatus developed for these endeavors turned out to be perfectly suited for exploring the possibility of making absolute optical frequency measurements of atomic transitions. We initiated collaboration with researchers at NIST so that the desired optical frequencies could be reference with respect to the primary microwave frequency standard (Cs atomic fountain NIST-FI) via a femtosecond laser frequency comb. Our first absolute optical frequency measurement, of the cesium D2 line, surpassed the accuracy of a previous measurement by more than an order of magnitude. An absolute optical frequency measurement of the cesium D1 line, now near completion, also surpasses previous results and places us in a position to be able to report a new value for the fine structure constant which is the fundamental dimensionless constant that underlies all electromagnetic interactions.

Tanner, Carol E.

2005-03-04

327

Measurements of total and inelastic cross sections in positron-Cs and electron-Cs collisions  

NASA Astrophysics Data System (ADS)

We report measurements of total, positronium (Ps) formation, and excitation cross sections for 0.1 60-eV positrons (e+’s) and total and excitation cross sections for 6 200-eV electrons ( e- ’s) scattered by Cs atoms. Ps formation cross sections are measured by both detecting ? ray coincidences and a beam transmission technique while all other cross sections are measured using beam transmission techniques. We discuss our findings and compare them with other experimental results and theoretical calculations.

Surdutovich, E.; Kauppila, W. E.; Kwan, C. K.; Miller, E. G.; Parikh, S. P.; Price, K. A.; Stein, T. S.

2007-03-01

328

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

329

Measurement of the ?b0 lifetime and mass in the ATLAS experiment  

NASA Astrophysics Data System (ADS)

A measurement of the ?b0 lifetime and mass in the decay channel ?b0?J/?(?+?-)?0(p?-) is presented. The analysis uses a signal sample of about 2200 ?b0 and ?¯b0 decays that are reconstructed in 4.9fb-1 of ATLAS pp collision data collected in 2011 at the LHC center-of-mass energy of 7 TeV. A simultaneous mass and decay time maximum likelihood fit is used to extract the ?b0 lifetime and mass. They are measured to be ??b=1.449±0.036(stat)±0.017(syst)ps and m?b=5619.7±0.7(stat)±1.1(syst)MeV.

Aad, G.; Abajyan, T.; Abbott, B.; Abdallah, J.; Abdel Khalek, S.; Abdelalim, A. A.; Abdinov, O.; Aben, R.; Abi, B.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Acerbi, E.; Acharya, B. S.; Adamczyk, L.; Adams, D. L.; Addy, T. N.; Adelman, J.; Adomeit, S.; Adragna, P.; Adye, T.; Aefsky, S.; Aguilar-Saavedra, J. A.; Agustoni, M.; Aharrouche, M.; Ahlen, S. P.; Ahles, F.; Ahmad, A.; Ahsan, M.; Aielli, G.; Akdogan, T.; Åkesson, T. P. A.; Akimoto, G.; Akimov, A. V.; Alam, M. S.; Alam, M. A.; Albert, J.; Albrand, S.; Aleksa, M.; Aleksandrov, I. N.; Alessandria, F.; Alexa, C.; Alexander, G.; Alexandre, G.; Alexopoulos, T.; Alhroob, M.; Aliev, M.; Alimonti, G.; Alison, J.; Allbrooke, B. M. M.; Allport, P. P.; Allwood-Spiers, S. E.; Almond, J.; Aloisio, A.; Alon, R.; Alonso, A.; Alonso, F.; Alvarez Gonzalez, B.; Alviggi, M. G.; Amako, K.; Amelung, C.; Ammosov, V. V.; Amorim, A.; Amram, N.; Anastopoulos, C.; Ancu, L. S.; Andari, N.; Andeen, T.; Anders, C. F.; Anders, G.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Anduaga, X. S.; Anger, P.; Angerami, A.; Anghinolfi, F.; Anisenkov, A.; Anjos, N.; Annovi, A.; Antonaki, A.; Antonelli, M.; Antonov, A.; Antos, J.; Anulli, F.; Aoki, M.; Aoun, S.; Aperio Bella, L.; Apolle, R.; Arabidze, G.; Aracena, I.; Arai, Y.; Arce, A. T. H.; Arfaoui, S.; Arguin, J.-F.; Arik, E.; Arik, M.; Armbruster, A. J.; Arnaez, O.; Arnal, V.; Arnault, C.; Artamonov, A.; Artoni, G.; Arutinov, D.; Asai, S.; Asfandiyarov, R.; Ask, S.; Åsman, B.; Asquith, L.; Assamagan, K.; Astbury, A.; Aubert, B.; Auge, E.; Augsten, K.; Aurousseau, M.; Avolio, G.; Avramidou, R.; Axen, D.; Azuelos, G.; Azuma, Y.; Baak, M. A.; Baccaglioni, G.; Bacci, C.; Bach, A. M.; Bachacou, H.; Bachas, K.; Backes, M.; Backhaus, M.; Badescu, E.; Bagnaia, P.; Bahinipati, S.; Bai, Y.; Bailey, D. C.; Bain, T.; Baines, J. T.; Baker, O. K.; Baker, M. D.; Baker, S.; Banas, E.; Banerjee, P.; Banerjee, Sw.; Banfi, D.; Bangert, A.; Bansal, V.; Bansil, H. S.; Barak, L.; Baranov, S. P.; Barbaro Galtieri, A.; Barber, T.; Barberio, E. L.; Barberis, D.; Barbero, M.; Bardin, D. Y.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.; Barnett, B. M.; Barnett, R. M.; Baroncelli, A.; Barone, G.; Barr, A. J.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Barrillon, P.; Bartoldus, R.; Barton, A. E.; Bartsch, V.; Bates, R. L.; Batkova, L.; Batley, J. R.; Battaglia, A.; Battistin, M.; Bauer, F.; Bawa, H. S.; Beale, S.; Beau, T.; Beauchemin, P. H.; Beccherle, R.; Bechtle, P.; Beck, H. P.; Becker, A. K.; Becker, S.; Beckingham, M.; Becks, K. H.; Beddall, A. J.; Beddall, A.; Bedikian, S.; Bednyakov, V. A.; Bee, C. P.; Beemster, L. J.; Begel, M.; Behar Harpaz, S.; Beimforde, M.; Belanger-Champagne, C.; Bell, P. J.; Bell, W. H.; Bella, G.; Bellagamba, L.; Bellina, F.; Bellomo, M.; Belloni, A.; Beloborodova, O.; Belotskiy, K.; Beltramello, O.; Benary, O.; Benchekroun, D.; Bendtz, K.; Benekos, N.; Benhammou, Y.; Benhar Noccioli, E.; Benitez Garcia, J. A.; Benjamin, D. P.; Benoit, M.; Bensinger, J. R.; Benslama, K.; Bentvelsen, S.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Berghaus, F.; Berglund, E.; Beringer, J.; Bernat, P.; Bernhard, R.; Bernius, C.; Berry, T.; Bertella, C.; Bertin, A.; Bertolucci, F.; Besana, M. I.; Besjes, G. J.; Besson, N.; Bethke, S.; Bhimji, W.; Bianchi, R. M.; Bianco, M.; Biebel, O.; Bieniek, S. P.; Bierwagen, K.; Biesiada, J.; Biglietti, M.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Biscarat, C.; Bitenc, U.; Black, K. M.; Blair, R. E.; Blanchard, J.-B.; Blanchot, G.; Blazek, T.; Blocker, C.; Blocki, J.; Blondel, A.; Blum, W.; Blumenschein, U.; Bobbink, G. J.; Bobrovnikov, V. B.; Bocchetta, S. S.; Bocci, A.; Boddy, C. R.; Boehler, M.; Boek, J.; Boelaert, N.; Bogaerts, J. A.; Bogdanchikov, A.; Bogouch, A.; Bohm, C.; Bohm, J.; Boisvert, V.; Bold, T.; Boldea, V.; Bolnet, N. M.; Bomben, M.; Bona, M.; Boonekamp, M.; Booth, C. N.; Bordoni, S.; Borer, C.; Borisov, A.; Borissov, G.; Borjanovic, I.; Borri, M.; Borroni, S.; Bortolotto, V.; Bos, K.; Boscherini, D.; Bosman, M.; Boterenbrood, H.; Bouchami, J.; Boudreau, J.; Bouhova-Thacker, E. V.; Boumediene, D.; Bourdarios, C.; Bousson, N.; Boveia, A.; Boyd, J.; Boyko, I. R.; Bozovic-Jelisavcic, I.; Bracinik, J.; Branchini, P.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J. E.; Braun, H. M.; Brazzale, S. F.; Brelier, B.; Bremer, J.; Brendlinger, K.; Brenner, R.; Bressler, S.; Britton, D.; Brochu, F. M.; Brock, I.; Brock, R.; Broggi, F.; Bromberg, C.; Bronner, J.; Brooijmans, G.; Brooks, T.; Brooks, W. K.; Brown, G.; Brown, H.; Bruckman de Renstrom, P. A.; Bruncko, D.; Bruneliere, R.; Brunet, S.; Bruni, A.; Bruni, G.; Bruschi, M.; Buanes, T.; Buat, Q.; Bucci, F.; Buchanan, J.; Buchholz, P.; Buckingham, R. M.; Buckley, A. G.

2013-02-01

330

Differential lifetime measurements and identical superdeformed bands in {sup 192,194}Hg  

Microsoft Academic Search

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 Qâ were extracted for three SD bands in ¹⁹⁴Hg and for the yrast SD band in ¹⁹²Hg. Within experimental uncertainties, all four SD bands have equal Qâ values. These results provide constraints on differences in Qâ values between the

E. F. Moore; H. Amro; T. Lauritsen; R. V. Janssens; T. L. Khoo; D. Ackermann; I. Ahmad; D. Blumenthal; M. P. Carpenter; S. M. Fischer; G. Hackman; D. Nisius; F. Hannachi; A. Lopez-Martens; A. Korichi; S. Asztalos; R. M. Clark; M. A. Deleplanque; R. M. Diamond; P. Fallon; I. Y. Lee; A. O. Macchiavelli; F. S. Stephens; J. A. Becker; L. Bernstein; L. P. Farris; E. A. Henry

1997-01-01

331

Differential lifetime measurements and identical superdeformed bands in 192,194Hg  

Microsoft Academic Search

High-precision lifetime measurements have been performed in superdeformed (SD) bands of 192,194Hg with the Doppler-shift attenuation method. Intrinsic quadrupole moments Q0 were extracted for three SD bands in 194Hg and for the yrast SD band in 192Hg. Within experimental uncertainties, all four SD bands have equal Q0 values. These results provide constraints on differences in Q0 values between the ``identical''

E. F. Moore; T. Lauritsen; R. V. Janssens; T. L. Khoo; D. Ackermann; I. Ahmad; H. Amro; D. Blumenthal; M. P. Carpenter; S. M. Fischer; G. Hackman; D. Nisius; F. Hannachi; A. Lopez-Martens; A. Korichi; S. Asztalos; R. M. Clark; M. A. Deleplanque; R. M. Diamond; P. Fallon; I. Y. Lee; A. O. Macchiavelli; F. S. Stephens; J. A. Becker; L. Bernstein; L. P. Farris; E. A. Henry

1997-01-01

332

Lifetime Measurements in 128Cs and 132La as a Test of Chirality  

Microsoft Academic Search

The lifetime of levels in 128Cs and 132La have been measured in-beam of the Warsaw University Cyclotron using DSA method. The absolute M1 and E2 transition probabilities have been deduced. Two cases have been found: 132La where the B(E2) values in yrast and partner bands differ up to 30 times and 128Cs - the B(E2) values in both bands differ

E. Grodner; I. Zalewska; T. Morek; J. Srebrny; Ch. Droste; M. Kowalczyk; J. Mierzejewski; M. Salata; A. A. Pasternak; J. Kownacki; M. Kisielinski; A. Kordyasz; P. Napiorkowski; M. Wolinska; S. G. Rohozinski; R. Kaczarowski; W. Plóciennik; E. Ruchowska; A. Wasilewski; J. Perkowski

2005-01-01

333

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

334

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

Microsoft Academic Search

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

T. Aaltonen; J. Adelman; B. Álvarez González; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; J. Appel; A. Apresyan; T. Arisawa; A. Artikov; J. Asaadi; W. Ashmanskas; A. Attal; A. Aurisano; F. Azfar; W. Badgett; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; P. Barria; P. Bartos; G. Bauer; P.-H. Beauchemin; F. Bedeschi; D. Beecher; S. Behari; G. Bellettini; J. Bellinger; D. Benjamin; A. Beretvas; A. Bhatti; M. Binkley; D. Bisello; I. Bizjak; R. E. Blair; C. Blocker; B. Blumenfeld; A. Bocci; A. Bodek; V. Boisvert; D. Bortoletto; J. Boudreau; A. Boveia; B. Brau; A. Bridgeman; 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; C. Calancha; S. Camarda; M. Campanelli; M. Campbell; F. Canelli; A. Canepa; B. Carls; D. Carlsmith; R. Carosi; S. Carrillo; S. Carron; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; V. Cavaliere; 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; K. Chung; W. H. Chung; Y. S. Chung; T. Chwalek; C. I. Ciobanu; M. A. Ciocci; A. Clark; D. Clark; G. Compostella; M. E. Convery; J. Conway; M. Corbo; M. Cordelli; C. A. Cox; D. J. Cox; F. Crescioli; C. Cuenca Almenar; J. Cuevas; R. Culbertson; J. C. Cully; D. Dagenhart; N. D'Ascenzo; M. Datta; T. Davies; P. de Barbaro; S. de Cecco; A. Deisher; G. de Lorenzo; M. Dell'Orso; C. Deluca; L. Demortier; J. Deng; M. Deninno; M. D'Errico; A. di Canto; B. di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; P. Dong; T. Dorigo; S. Dube; K. Ebina; A. Elagin; R. Erbacher; D. Errede; S. Errede; N. Ershaidat; 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; M. J. Frank; M. Franklin; J. C. Freeman; I. Furic; M. Gallinaro; J. Galyardt; F. Garberson; J. E. Garcia; A. F. Garfinkel; P. Garosi; H. Gerberich; D. Gerdes; A. Gessler; S. Giagu; V. Giakoumopoulou; P. Giannetti; K. Gibson; J. L. Gimmell; C. M. Ginsburg; N. Giokaris; M. Giordani; P. Giromini; M. Giunta; G. Giurgiu; 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; S. R. Hahn; E. Halkiadakis; B.-Y. Han; J. Y. Han; F. Happacher; K. Hara; D. Hare; M. Hare; R. F. Harr; M. Hartz; K. Hatakeyama; C. Hays; M. Heck; J. Heinrich; M. Herndon; J. Heuser; S. Hewamanage; D. Hidas; C. S. Hill; D. Hirschbuehl; A. Hocker; S. Hou; M. Houlden; S.-C. Hsu; R. E. Hughes; B. T. Huffman; M. Hurwitz; U. Husemann; M. Hussein; J. Huston; J. Incandela; G. Introzzi; M. Iori; A. Ivanov; E. James; D. Jang; B. Jayatilaka; E. J. Jeon; M. K. Jha; 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; W. Ketchum; J. Keung; V. Khotilovich; B. Kilminster; D. H. Kim; H. S. Kim; H. W. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; N. Kimura; L. Kirsch; S. Klimenko; K. Kondo; D. J. Kong; J. Konigsberg; A. Korytov; A. V. Kotwal; M. Kreps; J. Kroll; D. Krop; N. Krumnack; M. Kruse; V. Krutelyov; T. Kuhr; N. P. Kulkarni; M. Kurata; S. Kwang; A. T. Laasanen; S. Lami; S. Lammel; M. Lancaster; R. L. Lander; K. Lannon; A. Lath; G. Latino; I. Lazzizzera; T. Lecompte; E. Lee; H. S. Lee; J. S. Lee; S. W. Lee; S. Leone; J. D. Lewis; C.-J. Lin; J. Linacre; M. Lindgren; E. Lipeles; A. Lister; D. O. Litvintsev; C. Liu; T. Liu; N. S. Lockyer; A. Loginov; L. Lovas; D. Lucchesi; J. Lueck; P. Lujan; P. Lukens; G. Lungu; L. Lyons; J. Lys; R. Lysak; D. MacQueen; R. Madrak; K. Maeshima; K. Makhoul; P. Maksimovic; S. Malde; S. Malik; G. Manca; A. Manousakis-Katsikakis; F. Margaroli; C. Marino; A. Martin; V. Martin; M. Martínez; R. Martínez-Ballarín; P. Mastrandrea; M. Mathis; M. E. Mattson; P. Mazzanti; K. S. McFarland; P. McIntyre; R. McNulty; A. Mehta; P. Mehtala; A. Menzione; C. Mesropian; T. Miao; D. Mietlicki; N. Miladinovic; R. Miller; C. Mills; M. Milnik; A. Mitra; G. Mitselmakher; H. Miyake; S. Moed; N. Moggi; M. N. Mondragon; C. S. Moon; R. Moore; M. J. Morello; J. Morlock; P. Movilla Fernandez; J. Mülmenstädt; A. Mukherjee; Th. Muller; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; J. Naganoma; K. Nakamura; I. Nakano; A. Napier; J. Nett; C. Neu; M. S. Neubauer; S. Neubauer; J. Nielsen; L. Nodulman; M. Norman; O. Norniella; E. Nurse; L. Oakes; S. H. Oh; Y. D. Oh; I. Oksuzian; T. Okusawa; R. Orava; K. Osterberg; S. Pagan Griso; C. Pagliarone; E. Palencia; V. Papadimitriou; A. Papaikonomou; A. A. Paramanov; B. Parks; S. Pashapour; J. Patrick; G. Pauletta; M. Paulini; C. Paus; T. Peiffer; D. E. Pellett

2011-01-01

335

Single molecule spectroscopy. Fluorescence-lifetime measurements of pentacene in p-terphenyl  

NASA Astrophysics Data System (ADS)

The fluorescence lifetime of single pentacene molecules in the O 1 site of p-terphenyl at a temperature of 1.8 K has been measured. Individual molecules were repetitively excited by monochormatic Fourier transform limited light pulses with a duration of 9 ns. The time-correlated single-photon counting technique was employed to generate a histogram of the time distribution of the fluorescence photons emitted by single molecules.

Pirotta, Marco; Gütter, Frank; Gygax, Hansruedi; Renn, Alois; Sepiol, Jerzy; Wild, Urs P.

1993-06-01

336

Characterization of ZnSe(Te) scintillators by frequency domain luminescence lifetime measurements  

NASA Astrophysics Data System (ADS)

Dynamics of photoluminescence (PL) decay in Te-doped ZnSe scintillator crystal is studied using frequency domain luminescence lifetime measurement technique, which enables simultaneous characterization of components in multicomponent PL decay in a wide time window ranging from millisecond to nanosecond domain. Evolution of decay times and relative contributions of the decay components corresponding to different PL decay mechanisms was revealed as a function of temperature.

Mickevi?ius, J.; Tamulaitis, G.; Vitta, P.; Žukauskas, A.; Starzhinskiy, N.; Ryzhikov, V.

2009-10-01

337

Nuclear structure studies of {sup 70}Zn from g-factor and lifetime measurements  

SciTech Connect

The g factors and mean lifetimes of several short-lived low-lying states in {sub 30}{sup 70}Zn{sub 40} have been measured using the techniques of projectile Coulomb excitation in inverse kinematics combined with transient magnetic fields and the Doppler-shift attenuation method. The present results have been interpreted within the framework of large-scale shell-model calculations that include the g{sub 9/2} orbital.

Muecher, D. [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln (Germany); Guerdal, G.; Kumbartzki, G. J.; Benczer-Koller, N.; Sharon, Y. Y.; Zamick, L.; Krieger, B. [Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854 (United States); Speidel, K.-H. [Helmholtz-Institut fuer Strahlen- und Kernphysik, Universitaet Bonn, Nussallee 14-16, D-53115 Bonn (Germany); Robinson, S. J. Q. [Physics Department, Millsaps College, Jackson, Mississippi 39210 (United States); Lisetskiy, A. F. [Department of Physics, University of Arizona, Tucson, Arizona 85721 (United States); Casperson, R. J.; Heinz, A.; Werner, V.; Williams, E.; Winkler, R. [A. W. Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520 (United States); Leske, J. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgartenstr. 9, D-64289 Darmstadt (Germany); Maier-Komor, P. [Physik-Department, Technische Universitaet Muenchen, James-Franck-Str., D-85748 Garching (Germany)

2009-05-15

338

Measurement of the Lambda0b Lifetime Using Lambda0b-->Lambda+cl-nu¯  

Microsoft Academic Search

The lifetime of Lambda0b is measured using the semileptonic decay Lambda0b-->Lambda+cl-nu¯, where the Lambda+c is reconstructed through its decay Lambda+c-->pK-pi+. The data were collected by the CDF detector at the Tevatron Collider during 1992-1995 and correspond to an integrated luminosity of 110 pb-1 of pp¯ collisions at s = 1.8 TeV. From a fit to the decay length distribution of

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. S. Chang; P. T. Chang; 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; R. Demina; 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; H. Kambara; 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; T. Miao; G. Michail; R. Miller; H. Minato; S. Miscetti; M. Mishina; H. Mitsushio; T. Miyamoto; S. Miyashita; N. Moggi; 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. Oliveira; 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; 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; F. D. Snider; T. Song; J. Spalding; T. Speer; 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. van den Brink; S. Vejcik III; G. Velev; R. Vidal

1996-01-01

339

Anomalous photoconductivity decay observed in microwave measurements of carrier lifetime in silicon ingots  

Microsoft Academic Search

A brief description is given of a microwave noncontact method for measuring excess-carrier lifetime in which a base of the\\u000a ingot under investigation is selected for pulsed illumination. The method is employed in an experiment on silicon ingots placed\\u000a between an emitting and a receiving waveguide, with the illumination provided by a 1.06-?m semiconductor laser. With an illuminated\\u000a area of

P. A. Borodovskii; A. F. Buldygin; A. S. Tokarev

2006-01-01

340

Direct measurement of the radiative lifetime of vibrationally excited OH radicals  

Microsoft Academic Search

Neutral molecules, isolated in the gas-phase, can be prepared in a long-lived\\u000aexcited state and stored in a trap. The long observation time afforded by the\\u000atrap can then be exploited to measure the radiative lifetime of this state by\\u000amonitoring the temporal decay of the population in the trap. This method is\\u000ademonstrated here and used to benchmark the

Sebastiaan Y. T. van de Meerakker; N. van Haecke; Gerrit C. Groenenboom; Gerard Meijer

2005-01-01

341

Evaluating electronic decay in wide band gap semiconductors using contactless thermally stimulated lifetime measurements  

NASA Astrophysics Data System (ADS)

Electronic decay behavior in wide band gap semiconductor materials using a contactless method is observed. Experiments are performed to measure electronic decay behavior as a function of temperature and surface quality. Also a mathematical model of the observed electronic behavior is created and assists in the understanding of observed behavior. In the first study a crystal of Cd1-xZnxTe (CZT) is pumped with a 5ns pulsed 1064 nm wavelength laser light and probed by a contactless method. Varying the temperature through a range of 110K to 290 K, the carrier lifetime of CZT decreased from approximately 30 microseconds at 110K to 4 microseconds at 160K, and then remained relatively constant to 290K. The sudden drop in carrier lifetime within a particular temperature range is consistent with thermal activation of a charge trap with a detrapping time longer than the carrier lifetime. The maximum trap activation temperature and the minimum detrapping time are estimated from the lifetime versus temperature curve to be approximately 160K and 10-6 s, respectively. In the next study, a crystal of CZT that has been mechanically cut is gradually etched using a Bromine/Methanol solution. With an improvement of surface quality an increase in carrier lifetime is observed at low temperature. To further assist us in the understanding of the observed electronic behavior in CZT a model of the electronic behavior is created. The modeled behavior plotted along side the experimental data provides a method to calculated trap energies within the band gaps of semiconductor materials. Using the model a recombination center at energy of .600--.700 eV is determined to exist from the bands edge for CZT. The method developed from the investigation of CZT is applied to another wide band gap semiconductor, mercuric iodide. Similar investigations are performed as well as a tentative evaluation of nonstochoimetry has upon electronic behavior of mercuric iodide.

Kessick, Royal Franklin, III

342

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

PubMed

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

2013-07-19

343

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.

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

2013-01-01

344

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

SciTech Connect

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{sup -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; Du Shan [College of Physics, Jilin University, Changchun 130021 (China); Key Lab of Coherent Light, Atomic and Molecular Spectroscopy, Ministry of Education, Changchun 130021 (China); Palmeri, Patrick [Astrophysique et Spectroscopie, Universite de Mons, B-7000 Mons (Belgium); Quinet, Pascal; Biemont, Emile [Astrophysique et Spectroscopie, Universite de Mons, B-7000 Mons (Belgium); IPNAS (Bat. B15), Universite de Liege, Sart Tilman, B-4000 Liege (Belgium); Dai Zhenwen [College of Physics, Jilin University, Changchun 130021 (China); Key Lab of Coherent Light, Atomic and Molecular Spectroscopy, Ministry of Education, Changchun 130021 (China); Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012 (China)

2010-10-15

345

Minority carrier lifetime and iron concentration measurements on p-Si wafers by infrared photothermal radiometry and microwave photoconductance decay  

NASA Astrophysics Data System (ADS)

A comparative study of electronic transport properties of p-Si wafers intentionally contaminated with Fe was performed using infrared photothermal radiometry (PTR) and microwave photoconductance decay (?-PCD). Strong correlations were found between PTR and ?-PCD lifetimes in a lightly contaminated wafer with no significant PTR transient behavior. The absolute PTR lifetime values were larger than the local averaged ?-PCD values, due to the different excitation wavelengths and probe depths. In a heavily contaminated wafer the ?-PCD and PTR lifetime correlation was poorer. PTR measurements were highly sensitive to iron concentration, most likely due to the dependence of the bulk recombination lifetime on it. Rapid-scanned (nonsteady-state) PTR images of the wafer surface exhibited strong correlations with both ?-PCD lifetime and [Fe] concentration images in both heavily and lightly contaminated wafers. For the lightly and uniformly contaminated wafer, PTR scanning imaging was found to be more sensitive to iron concentration and lifetime variations than ?-PCD images.

Rodríguez, M. E.; Mandelis, A.; Pan, G.; García, J. A.; Gorodokin, V.; Raskin, Y.

2000-06-01

346

Noninvasive in vivo measurement of vascular inflammation with F-18 fluorodeoxyglucose positron emission tomography  

Microsoft Academic Search

Background  Fluorine 18 fluorodeoxyglucose (FDG) has been shown to accumulate in inflamed tissues. However, it is not known whether vascular\\u000a inflammation can be measured noninvasively. The aim of this study was to test the hypothesis that vascular inflammation can\\u000a be measured noninvasively by use of positron emission tomography (PET) with FDG.\\u000a \\u000a \\u000a \\u000a Methods and Results  Inflamed atherosclerotic lesions were induced in 9 male

Ahmed Tawakol; Raymond Q. Migrino; Udo Hoffmann; Suhny Abbara; Stuart Houser; Henry Gewirtz; James E. Muller; Thomas J. Brady; Alan J. Fischmanb

2005-01-01

347

Helium bubbles in neutron-irradiated copper-boron studied by positron annihilation  

Microsoft Academic Search

The influence of helium, introduced by the B(n, ?)Li reaction, on the evolution of defect structure in copper containing a few hundred ppm boron has been studied by detailed positron lifetime and two-photon angular correlation measurements, supplemented by TEM studies. In the as-irradiated state of Cu-B, two lifetime components have been resolved. The shorter lifetime, ?1, = 167 ps of

B. Viswanathan; G. Amarendra; K. P. Gopinathan

1989-01-01

348

Positron trapping and possible presence of SO3H clusters in dry fluorinated polymer electrolyte membranes  

NASA Astrophysics Data System (ADS)

The behavior of positrons that do not form positronium in dry fluorinated polymer electrolyte membranes (Nafion®, Fumapem® and Aquivion®) with various ion exchange capacities (IECs) was studied by the combined use of Doppler broadening of annihilation radiation (DBAR) and the positron lifetime technique. The drastic increase of the S parameter, measured by DBAR, with increasing IEC above 0.91 meq/g indicates that increasing numbers of positrons are trapped by oxygen atoms and annihilate with the electrons bound in them. Reversed micelle like SO3H nanoclusters to trap positrons possibly appear at IEC = 0.91 meq/g and their concentration increases with increasing IEC.

Mohamed, Hamdy F. M.; Kobayashi, Y.; Kuroda, S.; Ohira, A.

2012-08-01

349

MEASUREMENTS OF NATURAL SELECTION ON FLORAL TRAITS IN WILD RADISH (RAPHANUS RAPHANISTRUM). I. SELECTION THROUGH LIFETIME FEMALE FITNESS  

Microsoft Academic Search

Although the role of natural selection in the evolution of floral traits has been of great interest to biologists since Darwin, studies of selection on floral traits through differences in lifetime fitness have been rare. We measured selection acting on flower number, flower size, stigma exsertion, and ovule number per flower using field data on lifetime female fitness (seed production)

JEFFREY K. CONNER; PETER JENNET; E. Healey

350

Identification and Quantification of Transition Metal Impurities in Czochralski Silicon Wafers using Microwave Photoconductive Decay Lifetime Measurements  

Microsoft Academic Search

The identification of metallic impurities in p-type silicon has been studied using a microwave photoconductive decay lifetime measurement method at various high injection levels. The light illumination time and carrier injection level dependences of the recombination lifetime show unique characteristics for recombination centers attributed to Fe- and Cr-related levels. The clear identification of iron and chromium is achieved by analyzing

Kazunari Kurita; Takayuki Shingyouji

1998-01-01

351

LIFETIME MEASUREMENT WITH PSEUDO MOVEABLE SEPTUM IN NSLS X-RAY RING  

SciTech Connect

The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source currently under construction at Brookhaven National Laboratory and starts to commission in 2014. The beam injection works with two septa and four fast kicker magnets in an injection section. To improve the injection stability and reproducibility, we plan to implement a slow local bump on top of the fast bump so that the fast kicker strength is reduced. This bump works as a pseudo movable septum. We can also use this 'movable' septum to measure the storage ring beam partial lifetime resulting from the septum edge and possibly increasing the lifetime by moving the stored beam orbit away from the edge. We demonstrate the feasibil