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1

Positron lifetimes of polycrystalline metals: A positron source correction study  

NASA Astrophysics Data System (ADS)

Positron lifetime measurements have been made on a series of polycrystalline metals with atomic numbers varying from 13 to 82, using positron sources deposited on Ni, Al, and Kapton support foils. Bulk positron lifetimes for Al, Ni, Zr, In, and Pb are reported. The results support previous assignments of monovacancy lifetimes for Ag, Ta, and Pb. A method for obtaining the extrinsic positron lifetime components due to the radionuclide source is developed, and the experimentally determined source lifetime components are studied as a function of the sample atomic number. The Z dependence of the source foil component intensities were fitted using known expressions for positron backscatter and multiple scattering within the source sample geometry, neglecting backscatter from the foil. The foil material positron absorption coefficients were obtained and found to be comparable with the results of previous transmission experiments.

McGuire, S.; Keeble, D. J.

2006-11-01

2

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

3

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

NASA Astrophysics Data System (ADS)

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

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

2014-11-01

4

Temperature dependence of free volume of polyacrylamide gels studied by positron lifetime measurements  

NASA Astrophysics Data System (ADS)

Changes of positronium (Ps) cavity radii in polyacrylamide and poly( N-isopropylacrylamide) gels were studied from 120 to 300 K by positron lifetime technique and it has been shown that the Ps cavity radius in the hydrogels changes by three or four stages. Temperature dependence of the Ps cavity radius exhibits variations similar to common polymers around the glass transition temperature. Hydrophilicity of the polymer chains significantly affects the Ps cavity radius just below 273 K. These results suggest an important role of free volume on the state of water in hydrogels.

Ito, Kenji; Ujihira, Yusuke; Yamashita, Takashi; Horie, Kazuyuki

2000-06-01

5

Positron lifetime spectroscopy in thin polymer coatings  

NASA Technical Reports Server (NTRS)

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

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

1990-01-01

6

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

7

The free volume in dried and H2O-loaded biopolymers studied by positron lifetime measurements.  

PubMed

We present experiments on glucose-gelatin compounds using positron annihilation lifetime spectroscopy (PALS) in order to study the behavior of the free volume dependent on H2O loading, drying, and uniaxial pressure. A semiempirical quantum mechanical model was applied in order to correlate the lifetime of orthopositronium in nanoscaled voids to the void size. This allowed us to determine the absolute value of the mean void radius in the biopolymer samples. In addition, the variation of the total free volume of the differently treated samples is quantified and illustrated by a log-normal distribution function. Most interesting results have been obtained after saturation loading with H2O that leads to the formation of voids with a mean size of 84.3(1.9) Ĺ(3) and to an increase of the total free volume by a factor of 2.5. This observation in the swelled sample is explained by the entropy elastic regime well above the glass transition temperature that greatly facilitates the formation of free volume. Differential scanning calorimetry (DSC) measurements were performed in order to determine the glass transition temperature and to support the interpretation of the results obtained by PALS. PMID:25046083

Hugenschmidt, Christoph; Ceeh, Hubert

2014-08-01

8

Microstructural Characterization of Thin Polyimide Films by Positron Lifetime Spectroscopy  

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

9

Moisture dependence of positron lifetime in Kevlar-49  

NASA Technical Reports Server (NTRS)

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

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

1984-01-01

10

Microstructural Characterization of Polymers by Positron Lifetime Spectroscopy  

NASA Technical Reports Server (NTRS)

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

Singh, Jag J.

1996-01-01

11

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

12

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

NASA Astrophysics Data System (ADS)

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

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

2011-08-01

13

Moisture determination in composite materials using positron lifetime techniques  

NASA Technical Reports Server (NTRS)

A technique was developed which has the potential of providing information on the moisture content as well as its depth in the specimen. This technique was based on the dependence of positron lifetime on the moisture content of the composite specimen. The positron lifetime technique of moisture determination and the results of the initial studies are described.

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

1980-01-01

14

Positron lifetime setup based on DRS4 evaluation board  

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

15

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 Foŕ; F Forti; A Giassi; M A Giorgi; A Gregorio; F Ligabue; A Lusiani; P S Marrocchesi; A Messineo; G Rizzo; G Sanguinetti; A Sciabŕ; 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

16

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

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

17

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

PubMed

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

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

2014-12-01

18

Investigation of nanocrystalline CoFe2O4 by positron annihilation lifetime spectroscopy  

Microsoft Academic Search

Nanoparticles of cobalt ferrite prepared by the co-precipitation method with crystallite size varying from 4.7 to 41 nm have been characterized by positron annihilation lifetime spectroscopy. Three lifetime components are fitted to the lifetime data. The shortest lifetime component is attributed to the delocalized positron lifetime shortened by defect trapping. The intermediate lifetime is assigned to the positron annihilation in

S. Bandyopadhyay; A. Roy; D. Das; S. S. Ghugre; J. Ghose

2003-01-01

19

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

20

Customer Lifetime Value Measurement  

Microsoft Academic Search

The measurement of customer lifetime value is important because it is used as a metric in evaluating decisions in the context of customer relationship management. For a firm, it is important to form some expectations as to the lifetime value of each customer at the time a customer starts doing business with the firm, and at each purchase by the

Sharad Borle; Siddharth S. Singh; Dipak C. Jain

2008-01-01

21

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

22

Study of defects in electron irradiated CuInSe{sub 2} by positron lifetime spectroscopy  

SciTech Connect

CuInSe{sub 2} was studied in the as-grown state and after low-temperature (4 K) 2 MeV electron irradiation. The positron bulk lifetime of 235 ps was measured for the unirradiated sample. The positron bulk lifetime was theoretically calculated and is in good agreement with the experimental value. In addition, the defect-related lifetimes for mono-, di-, and trivacancies are theoretically determined. An increased average positron lifetime indicated after electron irradiation the appearance of open-volume defects, most probably of divacancy type. The disappearance of this defect was observed during annealing below 250 K. Other defects were formed leading to a divacancy signal at least stable up to 600 K in the temperature range above 450 K. {copyright} {ital 1998 American Institute of Physics.}

Polity, A.; Krause-Rehberg, R.; Staab, T.E. [Fachbereich Physik, Universitaet Halle, D-06099 Halle (Saale) (Germany)] [Fachbereich Physik, Universitaet Halle, D-06099 Halle (Saale) (Germany); Puska, M.J. [Laboratory of Physics, Helsinki University of Technology, 02150 Espoo (Finland)] [Laboratory of Physics, Helsinki University of Technology, 02150 Espoo (Finland); Klais, J.; Moeller, H.J. [Fachbereich Physik, Technische Universitaet Bergakademie Freiberg, D-09599 Freiberg (Germany)] [Fachbereich Physik, Technische Universitaet Bergakademie Freiberg, D-09599 Freiberg (Germany); Meyer, B.K. [Fachbereich Physik, Justus--Liebig--Universitaet Giessen, D-35392 Giessen (Germany)] [Fachbereich Physik, Justus--Liebig--Universitaet Giessen, D-35392 Giessen (Germany)

1998-01-01

23

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

NASA Astrophysics Data System (ADS)

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

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

2014-11-01

24

Muon lifetime measurement  

NASA Astrophysics Data System (ADS)

A simple experimental setup to measure the muon lifetime is presented. The muon detector consists of a sealed container with liquid scintillator coupled to a 2.5'' photomultiplier (PMT). A home-made electronics module controlled by the parallel port of a personal computer (PC) digitizes the time interval between two consecutive PMT pulses in a time window of 25.6 ?s. The muon lifetime is obtained by analysing thousands of double-pulse events in which the first pulse corresponds to a cosmic ray muon that stops inside the detector and the second to the decay electron coming from the weak decay of the muon. The background noise comes from random coincidences of pulses due to muons crossing the detector within the same time window. The PC is used as the data adquisition (DAQ) and data analysis computer. In addition to the muon lifetime, the charge ratio of cosmic ray muons and the capture rate of negative muons by carbon nuclei can be measured if the number of events is sufficiently high.

Villaseńor, Luis

1998-02-01

25

Study of Chemical Carcinogens by Positron Annihilation Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

We have used positron annihilation lifetime spectroscopy to study the carcinogens C21H20BrN3, C4H7Cl2O4P, CCl4, CHCl3, AlF3, C8H12N4O, C6H4Cl2 and the non-carcinogens H2O, AlCl3, CH2Cl2, C2H6OS. We have established a correlation between the annihilation characteristics of the studied compounds and their degree of carcinogenicity.

Pivtsaev, A. A.; Razov, V. I.; Karasev, A. O.

2013-11-01

26

Formation Energy in Al-Mg Alloy by Positron Annihilation Lifetime Technique (PALT)  

NASA Astrophysics Data System (ADS)

The propose of the present work is to study the interaction of positrons with quenched-in defects and clustered atoms to estimate formation enthalpy in series 50xx of commercial Al-Mg alloys, namely, 5049, 5051,5052 and 5083 at various concentrations: 1.9, 2.09, 2.46 and 4.44 wt % of Mg, respectively. Typically additional impurities were mainly Si, Fe, Cu, Cr and Ti. The monvacancy formation energy of Al-Mg alloys was measured from a trapping model analysis of the T-dependence of the positron lifetime.

Abedl-Rahman, Mamduh; Badawi, Emad A.; Hassan, Essmat Mahmoud; Yahya, Gamal

2002-09-01

27

Voids in mixed-cation silicate glasses: Studies by positron annihilation lifetime and Fourier transform infrared spectroscopies  

NASA Astrophysics Data System (ADS)

PALS in comparison with FTIR studies have been applied to investigate the structure of different oxide glasses. Three components of the positron lifetime ? (?1 para- and ?3 ortho-positronium and ?2 intermediate lifetime component) and their intensities were obtained. The results of the calculation of mean values of positron lifetimes for the investigated glasses showed the existence of a long-living component on the positron annihilation lifetime spectra. From the Tao-Eldrup formula we can estimate the size of free volume. On the basis of the measurements we can conclude that the size and fraction of free volume reaches the biggest value for the fused silica glass. The degree of network polymerisation increases void size.

Reben, M.; Golis, E.; Filipecki, J.; Sitarz, M.; Kotynia, K.; Jele?, P.; Grelowska, I.

2014-08-01

28

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

29

Ion implantation induced defects in Fe-Cr alloys studied by conventional positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

The influence of chromium on the radiation damage resistance of the iron based alloys has been studied using conventional positron annihilation lifetime spectroscopy (PALS). Experimental data evaluation has been supported by the former theoretical calculation of positron lifetimes in the studied materials and well-defined types of defects. For this purpose, density functional theory (DFT) computation method has been applied. The spectrum of used 22Na positron source was decomposed into discrete fractions to better calculate efficiency of near surface layers study. For the experimental simulation of a-radiation and obtaining of defined cascade collisions in the materials, helium implantation was used. Different level of the implanted dose (6.24×1017 - 3.12×1018 cm-2) corresponds to local damage up to 90 DPA acquired in thin <1 ?m region. Experimental measurement has been performed using the PALS technique on the four different Fe-Cr binary alloys (2.36; 4.62; 8.39; 11.62 wt% of Cr). The results showed that chromium has a significant effect on the size and density of the implanted defects and specific Cr content should prevent the vacancy clusters formation.

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

2011-01-01

30

Lifetime Measurements in ^162Dy  

NASA Astrophysics Data System (ADS)

There has been great debate over the existence of low-lying vibrational excitations in deformed nuclei -- The original picture presented by Bohr & Mottelson was one of collective vibrations superimposed on a deformed ground state shape, however empirically, it has been difficult to determine if the observed excitations are indeed vibrational in nature or excitations built on two-single particle states. One signature of collectivity is the extraction of absolute B(E2) transition probabilities from measured lifetimes. The complete spectroscopy of ^162Dy was recently published up to 4 MeV [1], we have measured the lifetimes of several levels in the ^162Dy nucleus using the GRID technique at The Institut Laue-Langevin in Grenoble, France. The Dy target was inserted into the core of a 60 MW high flux beam reactor and the line width was measured using a double flat crystal spectrometer (GAMS4) of perfect Silicon crystals. The GRID technique allows measurements of lifetimes from a few picoseconds and lower. Preliminary lifetime measurements will be presented.[4pt][1] A. Aprahamian, et al., Nucl. Phys. A 764 42 (2006). This work was supported by the NSF under contract number PHY07-58100.

Lesher, S. R.; Aprahamian, A.; de Haan, R. C.; Börner, H. G.; Jentschel, M.; Warner, D. D.; Casten, R. F.

2010-11-01

31

Measurement of charm meson lifetimes  

E-print Network

) fs, 1033.6 +/- 22.1(-12.7)(+9.9) fs, and 486.3 +/- 15.0(-5.1)(+4.9) 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...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Davis, Robin E. P.; Kravchenko, I.; Kwak, Nowhan; Zhao, L.

1999-06-01

32

Optimization of BaF2 positron-lifetime spectrometer geometry based on the Geant4 simulations  

NASA Astrophysics Data System (ADS)

Incorrect choice of measuring experimental geometry and energy windows for a positron-lifetime spectrometer with BaF2 scintillators can lead to a significant distortion in a measured spectrum. Contribution of the distorted events for a non-optimal geometry may exceed 50%. It reduces the measured lifetimes of the spectral components and redistributes their intensities. The Geant4 simulation allows to estimate an influence of the measuring geometry on the spectrum distortion and to choose the most appropriate energy windows. The optimal geometry with a lead absorber between detectors suppresses contribution of the distorted coincidences down to 1% providing sufficiently high count rate of true events.

Dubov, L. Yu.; Grafutin, V. I.; Funtikov, Yu. V.; Shtotsky, Yu. V.; Elnikova, L. V.

2014-09-01

33

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

E-print Network

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

Elnikova, L V

2009-01-01

34

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

E-print Network

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

L. V. Elnikova

2010-04-26

35

Kinetics of natural aging in Al-Mg-Si alloys studied by positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

The process of natural aging in pure ternary Al-Mg-Si alloys was studied by positron annihilation lifetime spectroscopy in real time in order to clarify the sequence and kinetics of clustering and precipitation. It was found that natural aging takes place in at least five stages in these alloys, four of which were directly observed. This is interpreted as the result of complex interactions between vacancies and solute atoms or clusters. One of the early stages of positron lifetime evolution coincides with a clustering process observed by differential scanning calorimetry (DSC) and involves the formation of a positron trap with ˜0.200 ns lifetime. In later stages, a positron trap with a higher lifetime develops in coincidence with the DSC signal of a second clustering reaction. Mg governs both the kinetics and the lifetime change in this stage. Within the first 10 min after quenching, a period of nearly constant positron lifetime was found for those Mg-rich alloys that later show an insufficient hardness response to artificial aging, the so-called “negative effect.” The various processes observed could be described by two effective activation energies that were found by varying the aging temperature from 10 to 37°C.

Banhart, J.; Lay, M. D. H.; Chang, C. S. T.; Hill, A. J.

2011-01-01

36

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

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

37

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

38

[Positron annihilation lifetime spectrometry (PALS) and its pharmaceutical applications].  

PubMed

PALS is one of the most widely used "nuclear probe" techniques for the tracking of the structural characteristics of materials. The method is based on the matter-energy equivalence principle recognized by Einstein: the electrons and positrons as particle-antiparticle pairs disappear in mutual destruction of particles, they annihilate with high-energy gamma-radiation, thus "particle-energy transition" occurs. The properties of the resulting radiation exactly correspond to the relevant properties of the electron and positron preceding the annihilation. Since electrons occur in all types of materials, the phenomenon of positron annihilation can play in any environment; consequently the method can be used for the analysis of each type of materials (crystalline and amorphous, organic and inorganic, biotic and abiotic). The present paper provides an overview of the theoretical physical background, the practical realization and evaluation of methods, their limitations, and summarizes the pharmaceutical applications published in recent years. PMID:22570984

Sebe, István; Szabó, Barnabás; Zelkó, Romána

2012-01-01

39

Systematics in positron annihilation lifetime analysis of high (Tc) superconducting transitions  

NASA Astrophysics Data System (ADS)

The lifetimes and momentum distributions of annihilating electron-positron pairs are changed in high Tc superconductors cooled below the superconducting transition. Since the initial observation of this phenomena is YBCO the observation of these effects was reproduced and extended to other high (Tc) systems. There is a general consistency of results in most families of superconductors. An exception to this is YBCO which shows strong sample dependence. These consistent features have led to a model relating the pairing of the positive charge carriers and the positron distribution as one explanation for the lifetime changes.

Howell, R. H.; Radousky, H. B.; Wachs, A. L.; Fluss, M. J.; Turchi, P. E. A.; Jean, Y. C.; Sundar, C. S.; Chu, C. W.; Shelton, R. N.; Hinks, D. G.

1989-06-01

40

Measurement of the ?-lepton lifetime at Belle  

SciTech Connect

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

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

2014-01-23

41

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

E-print Network

Z .Applied Surface Science 149 1999 97­102 Unfolding positron lifetime spectra with neural networks developed, a trained network could be a very effective and efficient alternative to the existing methods, with very short identification times. q 1999 Elsevier Science B.V. All rights reserved. Z .Keywords

PĂĄzsit, Imre

42

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

PubMed Central

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

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

2013-01-01

43

Free volume investigation of imidazolium ionic liquids from positron lifetime spectroscopy  

E-print Network

In this work, relationships between the free volume and various fundamental physical properties (density, surface tension and transport properties) of ionic liquids were investigated. Two imidazolium ionic liquids 1-butyl-3-methylimidazolium tris(pentafluoroethyl)trifluoro phosphate ([C4MIM][FAP]) and 1-butyl-3-methylimidazolium bis[bis(pentafluoroethyl)phosphinyl]imide ([C4MIM][FPI]) were measured by positron annihilation lifetime spectroscopy (PALS). Changes of the ortho-positronium lifetime (o-Ps) with different states (amorphous and crystalline) were depicted as completely as possible. The mean local free (hole) volume was calculated from the o-Ps lifetime in amorphous state for the samples. Comparison between and specific volume obtained from the temperature dependent mass density gave the specific hole densities Nf and the occupied volumes Vocc. Thermal expansion of hole volume was compared with molecular volume VM of [C4MIM][FAP] and [C4MIM][FPI] as well as five other ionic liquids from our previous works, a monotonically increasing correlation between the two quantities was displayed. Hole volume of [C4MIM][FAP] sample from PALS experiment was compared with the result from surface tension according to F\\"urth hole theory, good agreement exhibited. The free volume obtained from this work was applied to Cohen-Turnbull fitting of viscosity for [C4MIM][FPI] sample. The influence of the free volume to transport properties was investigated by the comparison of /VM with the viscosity and conductivity for various ionic liquids. Correlation between the free volume and the molecular volume of ionic liquids were explained by a schematic free volume model.

Yang Yu; Dana Bejan; Reinhard Krause-Rehberg

2014-04-01

44

Positron Diffusion in Metals  

Microsoft Academic Search

From positron lifetime measurements in seven powders of Fe, Co, Ni, and W, the positron diffusion constant in metals at 300°K is found to be D+=(1.0+\\/-0.5)×10-2 cm2\\/sec. This agrees with a theory based on positron-electron scattering. Evidence is presented that positrons are trapped in metal surface states.

Robert Paulin; Roger Ripon; Werner Brandt

1973-01-01

45

Recent measurements of the B hadron lifetime  

SciTech Connect

Recent measurements of the B hadron lifetime from PEP and PETRA experiments are presented. These measurements firmly establish that the B lifetime is long (approx.1 psec), implying that the mixing between the third generation of quarks and the lighter quarks is much weaker that the mixing between the first two generations.

Ong, R.A.

1987-12-01

46

Variation of free volume size and content of shape memory polymer — Polyurethane — Upon temperature studied by positron annihilation lifetime techniques and infrared spectroscopy  

Microsoft Academic Search

Positron annihilation lifetime measurement and Fourier transform infrared spectrometry were applied to the study of temperature dependencies of free volume parameters and hydrogen bonds in segmented polyurethane, specially fabricated as a shape memory polymer. The variation of free volumes in amorphous region were correlated to that of hydrogen bonding and the shape memory mechanism of polyurethane is elucidated from a

K. Ito; K. Abe; H. L. Li; Y. Ujihira; N. Ishikawa; S. Hayashi

1996-01-01

47

Updated measurement of the tau lifetime  

Microsoft Academic Search

We present an update of our measurement of the tau lepton lifetime, using data taken during 1992 and 1993 with the OPAL detector at LEP. The lifetime is determined from analyses of the impact parameters of tracks from tau decays to a single charged particle, and the reconstructed decay lenghts from the tau decays to three charged particles. With the

R J Akers; Gideon Alexander; J. Allison; K. J. Anderson; S. Arcelli; S. Asai; Alan Astbury; 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; J. Becker; C. Beeston; T. Behnke; K. W. Bell; G. Bella; P. Bentkowski; 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; C. Burgard; 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; M. Coupland; M. Cuffiani; S. Dado; C. Dallapiccolla; G. M. Dallavalle; C L Darling; S. de Jong; 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; P. A. Elcombe; P. G. Estabrooks; E. Etzion; H. G. Evans; Franco Luigi Fabbri; B. Fabbro; M. Fanti; 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; P D Grannis; E. Gross; J. Hagemann; G. G. Hanson; M. Hansroul; C. K. Hargrove; J. Hart; 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; D. A. Hinshaw; P. R. Hobson; D. Hochman; A. Höcker; R James Homer; A. K. Honma; R. E. Hughes-Jones; R. Humbert; P. Igo-Kemenes; H. Ihssen; 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; K. Kawagoe; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; B J King; J. King; S. Kluth; T. Kobayashi; M. Kobel; D. S. Koetke; T. P. Kokott; S. Komamiya; R V Kowalewski; R. Howard; P. Krieger; J. von Krogh; P. Kyberd; G. D. Lafferty; H. Lafoux; R. Lahmann; J. Lauber; J. G. Layter; P. Leblanc; P. Le Du; A. M. Lee; E. Lefebvre; M. H. Lehto; Daniel Lellouch; C. Leroy; J. Letts; L. Levinson; Z. Li; F. Liu; 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; P. Mättig; U. Maur; J A McKenna; T. J. McMahon; A. I. McNab; J. R. McNutt; F. Meijers; 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; U. Müller; B. Nellen; B. Nijjhar; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; C. J. Oram; M. J. Oreglia; S. Orito; J. P. Pansart; G. N. Patrick; M. J. Pearce; P. Pfister; P. D. Phillips; J. E. Pilcher; J L Pinfold; D. Pitman; D. E. Plane; P R Poffenberger; B. Poli; A. Posthaus; T. W. Pritchard; H. Przysiezniak; M. W. Redmond; D. L. Rees; D. Rigby; M. Rison; S. A. Robins; D. Robinson; J. M. Roney; E. Ros; S. Rossberg; 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; H. von der 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; R. W. Springer; M. Sproston; A. Stahl; C. Stegmann; K. Stephens; J. Steuerer; B. Stockhausen; R. Ströhmer; D. Strom; P. Szymanski; H. Takeda; T. Takeshita; S. Tarem; M. Tecchio; P. Teixeira-Dias; N. Tesch; M. A. Thomson; S. Towers; T. Tsukamoto; M. F. Turner-Watson; D. van den Plas; R. van Kooten; G. Vasseur; 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; W. Zeuner; G. T. Zorn

1994-01-01

48

A positron lifetime study of lanthanum and niobium doped Pb(Zr0.6Ti0.4)O3  

NASA Astrophysics Data System (ADS)

A study of vacancy-related defects in lanthanum and niobium doped PbZr0.6Ti0.4O3 with dopant concentrations of 0-6 and 0-4mol%, respectively has been performed using positron annihilation spectroscopy X-ray diffraction, and photoelectron spectroscopy. Positron lifetime as well as coincidence annihilation radiation Doppler line broadening measurements were carried out. It was found that the samples exhibit vacancylike defects that act as positron traps. Two main defect lifetime components were found in both sample sets one at ?150ps and one at ?300ps. These defect trapping sites can be attributed to single oxygen vacancies and A-site vacancies, respectively. Doppler line broadening measurements, however, do not show significant changes as a function of dopant concentrations in terms of shape S and wing W parameters.

Gottschalk, S.; Hahn, H.; Balogh, A. G.; Puff, W.; Kungl, H.; Hoffmann, M. J.

2004-12-01

49

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

E-print Network

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

The DIRAC collaboration

2005-05-20

50

The Influence of Heat Treatment and Mechanical Work on the Lifetimes of Positrons in Fe, Pd and Pd-H  

NASA Astrophysics Data System (ADS)

The influence of annealing temperature and stretching with external forces on lifetimes of positrons in Fe, Pd and Pd-H0.05 was investigated. It was found that in all of the examined cases the best fitting of the obtained spectrum of lifetimes of positrons to the theoretical model can be achieved with the assumption that the spectra consist of two components of lifetimes ?1 and ?2 and intensities I1 and I2, respectively. In rolled Fe and Pd, at a high degree of cold work, all the positrons annihilate from the trapping state in two types of defects of clearly different lifetimes. It was observed that dislocations in Fe become active in temperatures exceeding 923 K and in Pd-above 623 K. Deformation through one-axis stretching of Fe, Pd and PdH0.05 within the range of proportional elastic stresses, causes a decrease in lifetimes of positrons in defects of larger sizes. A hysteresis of component ?2 was observed at returning from the stressed state to the free one. Within the range of plastic deformations, changes in the long life component of the spectrum of positron lifetimes correlate with the changes in the length resulting from stretching with external forces.

Pietrzak, R.; Szatanik, R.; Smiatek, W.

51

Photo-degradation of Lexan polycarbonate studied using positron lifetime spectroscopy  

SciTech Connect

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

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

2013-02-05

52

A measurement of the b baryon lifetime  

Microsoft Academic Search

In 451 000 hadronic Z0 decays, recorded with the ALEPH detector at LEP, the yields of Lambdal- and Lambdal+ combinations are measured. Semileptonic decays of b baryons result in a signal of 122+\\/- 18 (stat.)-23+22 (syst.) Lambdal- combinations. From a fit to the impact parameter distributions of the leptons in the Lambdal- sample, the lifetime of b baryons is measured

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

1992-01-01

53

Measurement of Charmed Meson Lifetimes with Belle  

E-print Network

The lifetimes of charmed mesons have been measured using 2.75fb$^{-1}$ of data collected with the Belle detector at KEKB. Each candidate is fully reconstructed to identify the flavor of the charmed meson. The lifetimes are measured to be $\\tau(D^0)=(414.8\\pm3.8\\pm3.4)$ fs, $\\tau(D^+)=(1040^{+23}_{-22}\\pm18)$ fs and $\\tau(D_s^+)=(479^{+17}_{-16}{}^{+6}_{-8})$ fs, where the first error is statistical and the second error is systematic. The mixing parameter $y_{CP}$ is also measured through the lifetime difference of $D^0$ mesons decaying into CP-mixed states and CP eigenstates. We find $y_{CP}=(1.0^{+3.8}_{-3.5}{}^{+1.1}_{-2.1})%$, corresponding to a 95% confidence interval $-7.0%<\\ycp<8.7%$.

Tanaka, J

2001-01-01

54

Measurement of the Bs Meson Lifetime  

NASA Astrophysics Data System (ADS)

The lifetime of the Bs meson is measured using the semileptonic decay Bs-->D-sl+?X. The data sample consists of 19.3 pb-1 of ppŻ 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-->??-, ?-->K+K-. Using these events, the Bs meson lifetime is determined to be ?s = 1.42+0.27-0.23\\(stat\\)+/-0.11\\(syst\\) ps. A measurement of the Bs lifetime in a low statistics sample of exclusive Bs-->J/? ? decays is also presented in this paper.

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

1995-06-01

55

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

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

56

A measurement of the D s lifetime  

Microsoft Academic Search

The lifetime of the D s meson has been measured using the TASSO detector at PETRA and found to be (5.7{-2.6\\/+3.6}ą0.9)×10-13 s. The method used was to reconstruct fully the decay vertex of the channel D s -->varphipią, varphi--> K + K -.

W. Braunschweig; R. Gerhards; F. J. Kirschfink; H.-U. Martyn; P. Rosskamp; B. Bock; J. Eisenmann; H. M. Fischer; H. Hartmann; E. Hilger; A. Jocksch; V. Mertens; R. Wedemeyer; B. Foster; A. J. Martin; A. J. Sephton; E. Bernardi; Y. Eisenberg; A. Eskreys; K. Gather; H. Hultschig; K. Genser; P. Joos; U. Karshon; B. Klima; H. Kowalski; A. Ladage; B. Löhr; D. Lüke; P. Mättig; A. Montag; D. Notz; J. Pawlak; D. Trines; T. Tymieniecka; R. Walczak; G. Wolf; W. Zeuner; A. Kolanoski; T. Kracht; J. Krüger; E. Lohrmann; G. Poelz; K.-U. Poesnecker; D. M. Binnie; J. K. Sedgbeer; J. Shulman; D. Su; A. T. Watson; F. Barreiro; A. Leites; J. Del Peso; E. Ros; C. Balkwill; M. G. Bowler; P. N. Burrows; R. J. Cashmore; P. Dauncey; G. P. Heath; D. J. Mellor; P. Ratoff; I. Tomalin; J. M. Yelton; S. L. Lloyd; G. E. Forden; J. C. Hart; D. K. Hasell; D. H. Saxon; S. Brandt; M. Holder; L. Labarga; B. Neumann; G. Mikenberg; R. Mir; D. Revel; E. Ronat; A. Shapira; N. Wainer; G. Yekutieli; G. Baranko; A. Caldwell; M. Cherney; J. M. Izen; D. Muller; S. Ritz; D. Strom; M. Takashima; E. Wicklund; Sau Lan Wu; G. Zobernig

1987-01-01

57

A measurement of the D s lifetime  

Microsoft Academic Search

The lifetime of theDs meson has been measured using the TASSO detector at PETRA and found to be (5.7-2.6+3.6ą0.9)×10-13 s. The method used was to reconstruct fully the decay vertex of the channelDs??pą, ??K+K-.

W. Braunschweig; R. Gerhards; F. J. Kirschfink; H.-U. Martyn; P. Rosskamp; B. Bock; J. Eisenmann; H. M. Fischer; H. Hartmann; E. Hilger; A. Jocksch; V. Mertens; R. Wedemeyer; B. Foster; A. J. Martin; A. J. Sephton; E. Bernardi; Y. Eisenberg; A. Eskreys; K. Gather; H. Hultschig; K. Genser; P. Joos; U. Karshon; B. Klima; H. Kowalski; A. Ladage; B. Löhr; D. Lüke; P. Mättig; A. Montag; D. Notz; J. Pawlak; D. Trines; T. Tymieniecka; R. Walczak; G. Wolf; W. Zeuner; A. Kolanoski; T. Kracht; J. Krüger; E. Lohrmann; G. Poelz; K.-U. Poesnecker; D. M. Binnie; J. K. Sedgbeer; J. Shulman; D. Su; A. T. Watson; F. Barreiro; A. Leites; J. del Peso; E. Ros; C. Balkwill; M. G. Bowler; P. N. Burrows; R. J. Cashmore; P. Dauncey; G. P. Heath; D. J. Mellor; P. Ratoff; I. Tomalin; J. M. Yelton; S. L. Lloyd; G. E. Forden; J. C. Hart; D. K. Hasell; D. H. Saxon; S. Brandt; M. Holder; L. Labarga; B. Neumann; G. Mikenberg; R. Mir; D. Revel; E. Ronat; A. Shapira; N. Wainer; G. Yekutieli; G. Baranko; A. Caldwell; M. Cherney; J. M. Izen; D. Muller; S. Ritz; D. Strom; M. Takashima; E. Wicklund; Sau Lan Wu; G. Zobernig

1987-01-01

58

TRENDS IN LIFETIME MEASUREMENTS Dieter K. Schroder  

E-print Network

, contactless diffusion length/lifetime measurements with iron detection in commercial equipment. It spawned, was the discovery of iron-boron pair formation and dissociation in 1981.2 Initially, this was merely an interesting the interstitial iron, Fei, state in boron-doped wafers, was it possible to determine the iron density in a wafer.3

Schroder, Dieter K.

59

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

60

A measurement of the ? b 0 lifetime  

Microsoft Academic Search

The lifetime of the ?b0 baryon has been measured using 3.6 million hadronic Z0 decays recorded by the OPAL detector at LEP from 1990 to 1994. A sample of ?b0 decays is obtained using partially reconstructed semileptonic decays involving ?c+?? combinations, where the ?c+ is reconstructed from its decay to a pK??+ final state. From the 69 ą 13?c+?? combinations

R. Akers; G. Alexander; J. Allison; N. Altekamp; K. Ametewee; K. J. Anderson; S. Anderson; S. Arcelli; D. Axen; G. Azuelos; A. H. Ball; E. Barberio; R. J. Barlow; R. Bartoldus; J. R. Batley; G. Beaudoin; S. Bethke; A. Beck; G. A. Beck; C. Beeston; T. Behnke; K. W. Bell; G. Bella; S. Bentvelsen; P. Berlich; J. Bechtluft; O. Biebel; I. J. Bloodworth; P. Bock; H. M. Bosch; M. Boutemeur; S. Braibant; P. Bright-Thomas; R. M. Brown; A. Buijs; H. J. Burckhart; R. Bürgin; C. Burgard; 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; 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; J. Goldberg; D. M. Gingrich; 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; D. Karlen; J. Kanzaki; 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; X. C. Lou; 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; P. Schütz; M. Schulz; 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

61

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-DŻ 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

62

Precision measurement of positron fraction by AMS-02  

NASA Astrophysics Data System (ADS)

A precision measurement by AMS-02 of the positron fraction in primary cosmic rays is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to 250GeV,but the slope decreases by an order of magnitude from 20 to 250GeV. A systematic searching for positron anisotropy shows the data is consistent with the hypothesis of isotropy. The measurement of separate fluxes show smooth behavior of both electron and positron fluxes. Positron shows different spectral index than electron, and a change of spectral index is clearly seen at ~ 30GeV.

Xu, Weiwei

2014-06-01

63

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

NASA Astrophysics Data System (ADS)

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

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

2015-01-01

64

Measurement of the {tau} lifetime at SLD  

SciTech Connect

A measurement of the lifetime of the {tau} lepton has been made using a sample of 1671 {ital Z}{sup 0}{r_arrow}{tau}{sup +}{tau}{sup {minus}} decays collected by the SLD detector at the SLC. The measurement benefits from the small and stable collision region at the SLC and the precision pixel vertex detector of the SLD. Three analysis techniques have been used: decay length, impact parameter, and impact parameter difference methods. The combined result is {tau}{sub {tau}}=297{plus_minus}9 (stat){plus_minus}5(syst) fs.

Abe, K.; Abt, I.; Ahn, C.J.; Akagi, T.; Allen, N.J.; Ash, W.W.; Aston, D.; Baird, K.G.; Baltay, C.; Band, H.R.; Barakat, M.B.; Baranko, G.; Bardon, O.; Barklow, T.; Bazarko, A.O.; Ben-David, R.; Benvenuti, A.C.; Bienz, T.; Bilei, G.M.; Bisello, D.; Blaylock, G.; Bogart, J.R.; Bolton, T.; Bower, G.R.; Brau, J.E.; Breidenbach, M.; Bugg, W.M.; Burke, D.; Burnett, T.H.; Burrows, P.N.; Busza, W.; Calcaterra, A.; Caldwell, D.O.; Calloway, D.; Camanzi, B.; Carpinelli, M.; Cassell, R.; Castaldi, R.; Castro, A.; Cavalli-Sforza, M.; Church, E.; Cohn, H.O.; Coller, J.A.; Cook, V.; Cotton, R.; Cowan, R.F.; Coyne, D.G.; D`Oliveira, A.; Damerell, C.J.S.; Daoudi, M.; De Sangro, R.; De Simone, P.; Dell`Orso, R.; Dima, M.; Du, P.Y.C.; Dubois, R.; Eisenstein, B.I.; Elia, R.; Etzion, E.; Falciai, D.; Fero, M.J.; Frey, R.; Furuno, K.; Gillman, T.; Gladding, G.; Gonzalez, S.; Hallewell, G.D.; Hart, E.L.; Hasegawa, Y.; Hedges, S.; Hertzbach, S.S.; Hildreth, M.D.; Huber, J.; Huffer, M.E.; Hughes, E.W.; Hwang, H.; Iwasaki, Y.; Jackson, D.J.; Jacques, P.; Jaros, J.; Johnson, A.S.; Johnson, J.R.; Johnson, R.A.; Junk, T.; Kajikawa, R.; Kalelkar, M.; Kang, H.J.; Karliner, I.; Kawahara, H.; Kendall, H.W.; Kim, Y.; King, M.E.; King, R.; Kofler, R.R.; Krishna, N.M.; Kroeger, R.S.; Labs, J.F.; Langston, M.; Lath, A.; Lauber, J.A.; Leith, D.W.G.; Liu, M.X.; Liu, X.; Loreti, M.; Lu, A.; Lynch, H.L.; Ma, J.; Mancinelli, G.; Manly, S.; Mantovani, G.; Markiewicz, T.W.; Maruyama, T.; Massetti, R.; Masuda, H.; Mazzucato, E.; McKemey, A.K.; Meadows, B.T.; Messner, R.; Mockett, P.M.; Moffeit, K.C.; Mours, B.; Mueller, G.; Muller, D.; Nagamine, T.; Nauenberg, U.; Neal, H.; Nussbaum, M.; Ohnishi, Y.; Osborne, L.S.; Panvini, R.S.; Park, H.; Pavel, T.J.; Peruzzi, I.; Piccolo, M.; Piemontese, L.; Pieroni, E.; Pitts, K.T.; Plano, R.J.; Prepost, R.; Prescott, C.Y.; Punkar, G.D.; Quigley, J.; Ratcliff, B.N.; Reeves, T.W.; Reidy, J.; Rensing, P.E.; Rochester, L.S.; Rothberg, J.E.; Rowson, P.C.; (The SLD Collabor..

1995-11-01

65

Comparison study of lifetime measurement techniques  

NASA Astrophysics Data System (ADS)

A comparison study was conducted between three different techniques used to resolve iron contamination in silicon. Fourteen 8-inch type Si wafers were implanted with iron at seven doses ranging from 1 by 108 to 1 by 1012 cm-2. All 14 wafers including monitors were processed through an RTP chamber at 1100 degrees C for 6 min. Oxide thickness was measured on an ellipsometer. The wafers were measured by optical and thermal activation SPV, then the wafers were split in two sets. One set of seven wafers was measured by ELYMAT and the other set was measured by (mu) -PCD. Two different passivation techniques were used for (mu) -PCD, oxide and ethanol-iodine passivation. At low implant dose all three techniques have limitations. However (mu) -PCD shows the highest lifetime. At high Fe concentrations all three techniques tend to agree.

Quinones, Gladys G.; Allen, Emily L.

1998-08-01

66

Measurement of the F-Meson Lifetime  

E-print Network

VoLUME 56, NUMaER 17 PHYSICAL REVIEW LETTERS 28 ApR. iL 1986 Measurement of the F-Meson Lifetime C. Jung, S. Abachi, C. Akerlof, P. Baringer, I. Beltrami, D. Blockus, G. Bonvicini, B. Brabson, J. M. Brom, B. G. Bylsma, J. Chapman, B. Cork, R. De... (1985). 4H. Albrecht et a/. , Phys. Lett. 1538, 343 (1985). 5M. Althoff et a/. , Phys. Lett. 1368, 130 (1984). 6N. Ushida et al. , Phys. Rev. Lett. 51, 2362 (1983). ~R. Bailey et al. , Phys. Lett. 1398, 320 (1984). sH. -Y. Cheng, in Proceedings...

Baringer, Philip S.

1986-04-28

67

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

68

Positron beam position measurement for a beam containing both positrons and electrons  

SciTech Connect

Positron beam position measurement for the Advanced Photon Source (APS) linac beam is affected by the presence of electrons that are also captured and accelerated along with the positrons. This paper presents a method of measuring positron position in a beam consisting of alternating bunches of positrons and electrons. The method is based on Fourier analysis of a stripline signal at the bunching and first harmonic frequencies. In the presence of a mixed species beam, a certain linear combination of bunching and first harmonic signals depends only on the position and charge of one specie of particle. A formula is derived for the stripline signal at all harmonics of the bunching frequency and is used to compute expected signal power at the bunching and first harmonic frequencies for typical electron and positron bunch charges. The stripline is calibrated by measuring the signal power content at the bunching and first harmonic frequencies for a single species beam. A circuit is presented that will be used with an APS positron linac stripline beam position monitor to detect the bunching and first harmonic signals for a beam of positrons and electrons.

Sereno, N.S.; Fuja, R. [Argonne National Lab., IL (United States). Advanced Photon Source

1996-08-01

69

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

70

The influence of microstructure on the sintering process in crystalline metal powders investigated by positron lifetime spectroscopy: II. Tungsten powders with different powder-particle sizes  

Microsoft Academic Search

Compacts of tungsten powder with five different powder-particle sizes (from 0953-8984\\/11\\/7\\/010\\/img7 to 0953-8984\\/11\\/7\\/010\\/img8) are subjected to pressureless sintering. We investigate the change in microstructure during the sintering process by positron lifetime spectroscopy. So as to be able to distinguish between defects having the same positron lifetime, we investigate their kinetics when the sample is annealed. In particular, we consider the

T. E. M. Staab; R. Krause-Rehberg; B. Vetter; B. Kieback; G. Lange; P. Klimanek

1999-01-01

71

Reduction of Statistical Power Per Event Due to Upper Lifetime Cuts in Lifetime Measurements  

E-print Network

A cut on the maximum lifetime in a lifetime fit not only reduces the number of events, but also, in some circumstances dramatically, decreases the statistical significance of each event. The upper impact parameter cut in the hadronic B trigger at CDF, which is due to technical limitations, has the same effect. In this note we describe and quantify the consequences of such a cut on lifetime measurements. We find that even moderate upper lifetime cuts, leaving event numbers nearly unchanged, can dramatically increase the statistical uncertainty of the fit result.

Jonas Rademacker

2007-02-09

72

A measurement of the D 0 lifetime  

Microsoft Academic Search

We have determined the D 0 lifetime from reconstructed vertices of D 0 mesons produced in e + e - annihilations at an average center of mass energy of 42.2 GeV. From fifteen events the D 0 lifetime was determined to be (4.3{-1.4\\/+2.0}ą0.8)×10-13s.

M. Althoff; W. Braunschweig; R. Gerhards; F. J. Kirschfink; H.-U. Martyn; P. Rosskamp; W. Wallraff; B. Bock; J. Eisenmann; H. M. Fischer; H. Hartmann; A. Jocksch; H. Kolanoski; V. Mertens; R. Wedemeyer; B. Foster; E. Bernardi; Y. Eisenberg; A. Eskreys; K. Gather; H. Hultschig; P. Joos; B. Klima; H. Kowalski; A. Ladage; B. Löhr; D. Lüke; P. Mättig; D. Notz; D. Revel; E. Ronat; W. Schütte; D. Trines; T. Tymieniecka; R. Walczak; G. Wolf; W. Zeuner; E. Hilger; T. Kracht; H. L. Krasemann; J. Krüger; E. Lohrmann; G. Poelz; K.-U. Pösnecker; D. M. Binnie; P. J. Dornan; D. A. Garbutt; C. Jenkins; W. G. Jones; J. K. Sedgbeer; D. Su; J. Thomas; W. A. T. Wan Abdullah; F. Barreiro; E. Ros; M. G. Bowler; P. Bull; R. J. Cashmore; P. Dauncey; R. Devenish; G. Heath; D. J. Mellor; P. Ratoff; J. M. Yelton; S. L. Lloyd; G. E. Forden; J. C. Hart; D. K. Hasell; D. H. Saxon; S. Brandt; M. Holder; L. Labarga; B. Neumann; U. Karshon; G. Mikenberg; R. Mir; A. Montag; G. Yekutieli; A. Shapira; G. Baranko; A. Caldwell; M. Cherney; D. Demille; J. M. Izen; J. Messersmith; S. Ritz; D. Strom; M. Takashima; E. Wicklund; Sau Lan Wu; G. Zobernig

1986-01-01

73

A measurement of the D 0 lifetime  

Microsoft Academic Search

We have determined theD0 lifetime from reconstructed vertices ofD0 mesons produced ine+e- annihilations at an average center of mass energy of 42.2 GeV. From fifteen events theD0 lifetime was determined to be (4.3-1.4+2.0ą0.8)×10-13s.

M. Althoff; W. Braunschweig; R. Gerhards; F. J. Kirschfink; H.-U. Martyn; P. Rosskamp; W. Wallraff; B. Bock; J. Eisenmann; H. M. Fischer; H. Hartmann; A. Jocksch; H. Kolanoski; V. Mertens; R. Wedemeyer; B. Foster; E. Bernardi; Y. Eisenberg; A. Eskreys; K. Gather; H. Hultschig; P. Joos; B. Klima; H. Kowalski; A. Ladage; B. Löhr; D. Lüke; P. Mättig; D. Notz; D. Revel; E. Ronat; W. Schütte; D. Trines; T. Tymieniecka; R. Walczak; G. Wolf; W. Zeuner; E. Hilger; T. Kracht; H. L. Krasemann; J. Krüger; E. Lohrmann; G. Poelz; K.-U. Pösnecker; D. M. Binnie; P. J. Dornan; D. A. Garbutt; C. Jenkins; W. G. Jones; J. K. Sedgbeer; D. Su; J. Thomas; W. A. T. Wan Abdullah; F. Barreiro; E. Ros; M. G. Bowler; P. Bull; R. J. Cashmore; P. Dauncey; R. Devenish; G. Heath; D. J. Mellor; P. Ratoff; J. M. Yelton; S. L. Lloyd; G. E. Forden; J. C. Hart; D. K. Hasell; D. H. Saxon; S. Brandt; M. Holder; L. Labarga; B. Neumann; U. Karshon; G. Mikenberg; R. Mir; A. Montag; G. Yekutieli; A. Shapira; G. Baranko; A. Caldwell; M. Cherney; D. DeMille; J. M. Izen; J. Messersmith; S. Ritz; D. Strom; M. Takashima; E. Wicklund; Sau Lan Wu; G. Zobernig

1986-01-01

74

Temperature Dependent Lifetime Measurements Fluorescence from a Phosphor  

E-print Network

Temperature Dependent Lifetime Measurements of Fluorescence from a Phosphor by Dr. James E. Parks that fluoresces when excited, (4) to measure and analyze the temperature dependence of fluorescent light lifetimes) to learn computer-based data acquisition and analysis procedures for measuring temperature dependent

Dai, Pengcheng

75

Cosmic Ray Positrons at High Energies: A New Measurement  

E-print Network

We present a new measurement of the cosmic-ray positron fraction e+/(e+ + e-) obtained from the first balloon flight of the High Energy Antimatter Telescope (HEAT). Using a magnet spectrometer combined with a transition radiation detector, an electromagnetic calorimeter, and time-of-flight counters we have achieved a high degree of background rejection. Our results do not indicate a major contribution to the positron flux from primary sources. In particular, we see no evidence for the significant rise in the positron fraction at energies above ~10 GeV previously reported.

HEAT Collaboration

1995-05-30

76

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

E-print Network

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

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

2015-01-01

77

Improved measurement of the lifetime of the ? lepton  

Microsoft Academic Search

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

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; G. Beaudoin; 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; P. Bock; H. M. Bosch; M. Boutemeur; B. T. Bouwens; S. Braibant; P G Bright-Thomas; R. M. Brown; Helfried 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; D. Chrisman; S. L. Chu; P. E. L. Clarke; 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; 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; 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; D. M. Gingrich; J. Goldberg; M. J. Goodrick; W. Gorn; C. Grandi; E. Gross; 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; 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; A. Jawahery; P. W. Jeffreys; H. Jeremie; Martin Paul Jimack; A. Joly; G. Jones; M. Jones; R. W. L. Jones; U. Jost; P. Jovanovic; J I Kanzaki; D A Karlen; T. Kawamoto; Richard K Keeler; R. G. Kellogg; B. W. Kennedy; 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; D. Lanske; J. Lauber; J. G. Layter; A. M. Lee; E. Lefebvre; Daniel Lellouch; J. Letts; L. Levinson; C. Lewis; S. L. Lloyd; F. K. Loebinger; G. D. Long; B. Lorazo; Michael J Losty; J. Ludwig; A. Luig; A. Malik; M. Mannelli; S. Marcellini; C. Markus; A. J. Martin; J. P. Martin; G. Martinez; T. Mashimo; W. Matthews; P. Mättig; W. J. McDonald; J A McKenna; E. A. Mckigney; T. J. McMahon; A. I. McNab; 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; B. Nellen; B. Nijjhar; R. Nisius; S. W. O'Neale; F. G. Oakham; F. Odorici; H. O. Ogren; T. Omori; M. Palazzo; J. Pálinkás; J. P. Pansart; G. Pásztor; G. N. Patrick; M. J. Pearce; S. Petzold; J. E. Pilcher; J. Pinfold; D. E. Plane; P. Poffenberger; B. Poli; A. Posthaus; H. Przysiezniak; D. L. Rees; D. Rigby; M. G. Rison; S. A. Robins; N. Rodning; J. M. Roney; A. Rooke; E. Ros; A. M. Rossi; M. Rosvick; P. Routenburg; Y. Rozen; K. Runge; O. Runolfsson; D. R. Rust; R. Rylko; E. K. G. Sarkisyan; 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; J. Schwiening; W. G. Scott; T. G. Shears; B. C. Shen; C. H. Shepherd-Themistocleous; P. Sherwood; G. P. Siroli; A. Sittler; A. Skillman; T. J. Smith; G. A. Snow; R. Sobie; S. Söldner-Rembold; R. W. Springer; M. Sproston; A. Stahl; K. Stephens; J. Steuerer; B. Stockhausen; D. Strom; F. Strumia; P. Szymanski; R. Tafirout; H. Takeda; P. Taras; S. Tarem; M. Tecchio; M. Thiergen; M. A. Thomson; E. von Törne; S. Towers; M. Tscheulin; A. S. Turcot; M. F. Turner-Watson; P. Utzat; R. Van Kooten; G. Vasseur; M. Verzocchi; P. Vikas; M. 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; J. S. White; B. Wilkens; G. W. Wilson; J. A. Wilson; T. Wlodek; G W Wilson; S. Wotton; S. Xella; S. Yamashita; G. Yekutieli; K. Yoshimura; V. Zacek

1996-01-01

78

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

PubMed

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

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

2006-12-15

79

Energies 0.16 and 0.53 ev for Dislocation Recovery in AlSi11.35Mg0.23 by Positron Lifetime  

NASA Astrophysics Data System (ADS)

The recovery behavior of 20% plastically deformed AlSi11.35Mg0.23 in various stages of isochronal annealing is investigated by positron lifetime (LT). Experimental results show that the positron mean lifetime is a function of annealing temperature. The lifetime of the positron annihilating in a perfect lattice is 187.3 ps. It is 229.8 ps in a 20% deformed one. There are two regions in the isochronal annealing, one of them is related to the point defect and the other to the dislocation. The activation enthalpy for the dislocation is calculated from the isothermal study in the dislocation region from 575-675 K by slow and fast cooling and it is 0.16 ą 0.02 and 0.53 ą 0.06 eV, respectively.

Abdel-Rahman, M. A.; Abdallah, M. S.; Badawi, Emad A.

80

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

PubMed

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

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

2015-01-21

81

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

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

82

Options for the neutron lifetime measurements in traps  

SciTech Connect

Different geometries for the neutron lifetime measurements by the method of ultracold neutron storage in material traps and additional possibilities for the neutron storage in the magnetic storage ring are considered.

Pokotilovski, Yu. N. [Joint Institute for Nuclear Research (Russian Federation)

2010-05-15

83

Trapped positrons for high-precision magnetic moment measurements  

NASA Astrophysics Data System (ADS)

A single electron in a quantum cyclotron provides the most precise measurement of the electron magnetic moment, given in units of the Bohr magneton by g/2 = 1.001 159 652 180 73 (28) [0.28 ppt]. The most precise determination of the fine structure constant comes from combining this measurement with Standard Model theory, yielding alpha-1 = 137.035 999 173 (34) [0.25 ppb], limited by the experimental uncertainty of the electron g-value. The most stringent test of CPT symmetry in leptons comes from comparing the electron and positron magnetic moments, limited by the positron uncertainty at 4.2 ppt. A new high-stability apparatus has been built and commissioned for improved measurements of the electron and positron magnetic moments, a greatly improved test of lepton CPT symmetry, and an improved determination of the fine structure constant. These new measurements require robust positron loading from a retractable radioactive source that is small enough to avoid compromising the high-precision environment of our experiment. The design and implementation of such a scheme is a central focus of this work. Robust positron loading at a rate of 1-2 e+/min from a 6.5 muCi 22Na source has been demonstrated.

Hoogerheide, Shannon Michelle Fogwell

84

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

PubMed

The ratio of the ?b(0) baryon lifetime to that of the B(0) meson is measured using 1.0??fb(-1) of integrated luminosity in 7 TeV center-of-mass energy pp collisions at the LHC. The ?b(0) baryon is observed for the first time in the decay mode ?b(0)?J/?pK-, while the B(0) meson decay used is the well known B(0)?J/??+ K- mode, where the ?+ K- mass is consistent with that of the K(*0)(892) meson. The ratio of lifetimes is measured to be 0.976ą0.012ą0.006, in agreement with theoretical expectations based on the heavy quark expansion. Using previous determinations of the B(0) meson lifetime, the ?b(0) lifetime is found to be 1.482ą0.018ą0.012??ps. In both cases, the first uncertainty is statistical and the second systematic. PMID:25166658

Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjřrnstad, 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; Lefčvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Maratas, J; Marconi, U; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Maurice, E; Mazurov, A; Mc Skelly, B; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mordŕ, A; Morello, M J; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I

2013-09-01

85

Temperature Dependent Lifetime Measurements of Fluorescence from a Phosphor  

NSDL National Science Digital Library

Remote temperature measurements can be made by measuring the lifetimes of fluorescence of light emitted by a phosphor excited with pulsed ultraviolet light. The technique was first used to measure the temperature of the rotator of a centrifuge used to separate isotopes of uranium while it was spinning at an ultrahigh angular velocity. This experiment is a study of the principles involved and measurements are made of the lifetimes of a light from a phosphor as a function of temperature to establish a calibration function. While the initial measurement techniques involved a pulsed nitrogen laser, this experiment uses a newly developed and affordable apparatus that uses a pulsed ultraviolet LED for the measurement. Lifetimes on the order of 1 to 50 Âľsec are determined. Presented at the 2013 AAPT Summer Meeting in Portland, Oregon. W36: Advanced Labs Workshop

Parks, James E.

2013-10-02

86

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

87

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

88

Nanocluster-associated vacancies in nanocluster-strengthened ferritic steel as seen via positron-lifetime spectroscopy  

SciTech Connect

Nanocluster-strengthened ferritic alloys are promising as structural materials because of their excellent high-temperature strength and radiation-damage resistance. Recently, Fu et al. [Phys. Rev. Lett. 99, 225502 (2007)] predicted that vacancies play an essential role in the formation and stabilization of nanoclusters in these materials. Positron-lifetime spectroscopy has been used to test this theoretical prediction in a nanocluster-strengthened Fe-based alloy. Nanoclusters (2-4 nm in diameter) containing Ti, Y, and O have been observed in a mechanically alloyed ferritic steel by atom-probe tomography. Vacancy clusters containing four to six vacancies have also been found in this material. In contrast, no vacancy clusters were detected in similar alloys containing no nanoclusters. These results indicate that vacancies are a vital component of the nanoclusters in these alloys.

Xu, Jun [ORNL; Liu, C.T. [University of Tennessee, Knoxville (UTK); Miller, M [Oak Ridge National Laboratory (ORNL); Chen, Hongmin [University of Missouri

2009-01-01

89

The Effect of Alloying with Magnesium on the Annealing Behavior of Aluminum Alloys Studied by Positron Lifetime Technique  

NASA Astrophysics Data System (ADS)

The migration enthalpy Hivm for point defects and dislocations is estimated by using positron lifetime technique; point defects and dislocations are produced as a result of plastic deformation at room temperature (RT) for the decomposition sequence, namely 5005, 5052 and 5083, of commercial Al-Mg systems. The results show that Hivm for the three systems increases as the Mg content is increased to u1=0.34ą0.09 eV, u2=0.39ą0.12 eV, and u3=0.42ą0.08 eV for the point defect state, and u1=1.12ą0.08 eV and u2=1.37ą0.13 eV for the dislocation state to 5005 and 5052, respectively. All the data are analyzed in terms of the two state trapping model.

Abdel-Hamed, M. O.

90

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

91

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

NASA Technical Reports Server (NTRS)

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

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

1998-01-01

92

Simultaneous measurements of fluorescence lifetimes, anisotropy, and FRAP recovery curves  

NASA Astrophysics Data System (ADS)

We present fluorescence lifetime imaging (FLIM) and fluorescence anisotropy imaging along with translational diffusion measurements of living cells labelled with green fluorescent protein (GFP) recorded in a single experiment. The experimental set-up allows for time and polarization-resolved fluorescence images to be measured in every frame of a fluorescence recovery after photobleaching (FRAP) series. We have validated the method using rhodamine 123 in homogeneous solution prior to measurements of living A431 cells labelled with cdc42-GFP, for which the FRAP recovery exhibits an immobile fraction and the rotational mobility of the protein is hindered while the fluorescence lifetime fairly homogeneous across the cell. By eliminating the need for sequential measurements to extract fluorescence lifetimes and molecular diffusion coefficients we remove artefacts arising from changes in sample morphology and excessive photobleaching during sequential experiments.

Levitt, James A.; Chung, Pei-Hua; Alibhai, Dominic R.; Suhling, Klaus

2011-02-01

93

Measurement of the ?b0 Lifetime Using Semileptonic Decays  

NASA Astrophysics Data System (ADS)

We report a measurement of the ?b0 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 ?b0 baryon is reconstructed via the decay ?b0???Ż?c+X. Using 4437ą329 signal candidates, we measure the ?b0 lifetime to be ?(?b0)=1.290-0.110+0.119(stat)-0.091+0.087(syst)ps, which is among the most precise measurements in semileptonic ?b0 decays. This result is in good agreement with the world average value.

Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Aguilo, E.; Ahn, S. H.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Anastasoaie, M.; Ancu, L. S.; Andeen, T.; Anderson, S.; Andrieu, B.; Anzelc, M. S.; Arnoud, Y.; Arov, M.; Arthaud, M.; Askew, A.; Ĺsman, B.; Assis Jesus, A. C. S.; Atramentov, O.; Autermann, C.; Avila, C.; Ay, C.; Badaud, F.; Baden, A.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Banerjee, P.; Barberis, E.; Barfuss, A.-F.; Bargassa, P.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Beale, S.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Bellavance, A.; Benitez, J. A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Berntzon, L.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Biscarat, C.; Blazey, G.; Blekman, F.; Blessing, S.; Bloch, D.; Bloom, K.; Boehnlein, A.; Boline, D.; Bolton, T. A.; Borissov, G.; Bos, K.; Bose, T.; Brandt, A.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Buchanan, N. J.; Buchholz, D.; Buehler, M.; Buescher, V.; Burdin, S.; Burke, S.; Burnett, T. H.; Buszello, C. P.; Butler, J. M.; Calfayan, P.; Calvet, S.; Cammin, J.; Caron, S.; Carvalho, W.; Casey, B. C. K.; Cason, N. M.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chan, K.; Chandra, A.; Charles, F.; Cheu, E.; Chevallier, F.; Cho, D. K.; Choi, S.; Choudhary, B.; Christofek, L.; Christoudias, T.; Cihangir, S.; Claes, D.; Clément, C.; Clément, B.; Coadou, Y.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Crépé-Renaudin, S.; Cutts, D.; ?wiok, M.; da Motta, H.; Das, A.; Davies, G.; de, K.; de Jong, S. J.; de Jong, P.; de La Cruz-Burelo, E.; de Oliveira Martins, C.; Degenhardt, J. D.; Déliot, F.; Demarteau, M.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Dominguez, A.; Dong, H.; Dudko, L. V.; Duflot, L.; Dugad, S. R.; Duggan, D.; Duperrin, A.; Dyer, J.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Eno, S.; Ermolov, P.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Ford, M.; Fortner, M.; Fox, H.; Fu, S.; Fuess, S.; Gadfort, T.; Galea, C. F.; Gallas, E.; Galyaev, E.; Garcia, C.; Garcia-Bellido, A.; Gavrilov, V.; Gay, P.; Geist, W.; Gelé, D.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Ginther, G.; Gollub, N.; Gómez, B.; Goussiou, A.; Grannis, P. D.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guo, J.; Guo, F.; Gutierrez, P.; Gutierrez, G.; Haas, A.; Hadley, N. J.; Haefner, P.; Hagopian, S.; Haley, J.; Hall, I.; Hall, R. E.; Han, L.; Hanagaki, K.; Hansson, P.; Harder, K.; Harel, A.; Harrington, R.; Hauptman, J. M.; Hauser, R.; Hays, J.; Hebbeker, T.; Hedin, D.; Hegeman, J. G.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hensel, C.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hoeth, H.; Hohlfeld, M.; Hong, S. J.; Hooper, R.; Hossain, S.; Houben, P.; Hu, Y.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jakobs, K.; Jarvis, C.; Jesik, R.; Johns, K.; Johnson, C.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Juste, A.; Käfer, D.; Kahn, S.; Kajfasz, E.; Kalinin, A. M.; Kalk, J. R.; Kalk, J. M.; Kappler, S.; Karmanov, D.; Kasper, J.; Kasper, P.; Katsanos, I.; Kau, D.; Kaur, R.; Kaushik, V.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. M.; Khatidze, D.; Kim, H.; Kim, T. J.; Kirby, M. H.; Kirsch, M.; Klima, B.; Kohli, J. M.; Konrath, J.-P.; Kopal, M.; Korablev, V. M.; Kothari, B.; Kozelov, A. V.; Krop, D.; Kryemadhi, A.; Kuhl, T.; Kumar, A.; Kunori, S.; Kupco, A.; Kur?a, T.; Kvita, J.; Lacroix, F.; Lam, D.; Lammers, S.; Landsberg, G.; Lazoflores, J.; Lebrun, P.; Lee, W. M.; Leflat, A.; Lehner, F.; Lellouch, J.; Lesne, V.; Leveque, J.; Lewin, M.; Lewis, P.; Li, J.; Li, Q. Z.; Li, L.; Lietti, S. M.; Lima, J. G. R.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Liu, Z.; Lobo, L.; Lobodenko, A.; Lokajicek, M.; Lounis, A.; Love, P.; Lubatti, H. J.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madaras, R. J.; Mättig, P.; Magass, C.; Magerkurth, A.; Makovec, N.; Mal, P. K.; Malbouisson, H. B.; Malik, S.; Malyshev, V. L.; Mao, H. S.; Maravin, Y.; Martin, B.; McCarthy, R.; Melnitchouk, A.; Mendes, A.; Mendoza, L.; Mercadante, P. G.; Merkin, M.; Merritt, K. W.; Meyer, J.; Meyer, A.; Michaut, M.; Millet, T.; Mitrevski, J.; Molina, J.; Mommsen, R. K.; Mondal, N. K.; Moore, R. W.; Moulik, T.; Muanza, G. S.; Mulders, M.; Mulhearn, M.; Mundal, O.; Mundim, L.

2007-11-01

94

Measuring the Neutron Lifetime with Magnetically Trapped Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

We describe an experiment to measure the neutron lifetime using a technique with a set of systematic uncertainties largely different than those of previous measurements. In this approach, ultracold neutrons (UCN) are produced by inelastic scattering of cold (0.89 nm) neutrons in a reservoir of superfluid 4He. These neutrons are then confined using a three-dimensional magnetic trap. As the trapped neutrons beta decay, the energetic electrons produced in the decay generate scintillations in the liquid He; each decay is detectable with nearly 100 % efficiency. The neutron lifetime can be directly determined by measuring the scintillation rate as a function of time.

Mumm, H. P.; Huber, M. G.; Yue, A. T.; Thompson, A. K.; Dewey, M. S.; Huffer, C. R.; Huffman, P. R.; Schelhammer, K. W.; O'Shaughnessy, C.; Coakley, K. J.

2014-03-01

95

Measuring Carrier Lifetime in GaAs by Luminescence  

NASA Technical Reports Server (NTRS)

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

Von Roos, O.

1986-01-01

96

Measurement of femtosecond atomic lifetimes using ion traps  

NASA Astrophysics Data System (ADS)

Two types of experiment are described that both employ an electron beam ion trap for the production of highly charged ion species with the aim of then measuring atomic level lifetimes in the femtosecond range. In one experiment (done by Beiersdorfer et al. some time ago), the lifetime measurement depends on the associated line broadening. In a recent string of experiments at Linac Coherent Light Source Stanford, the HI-LIGHT collaboration employed pump-probe excitation using the FEL as a short-pulse X-ray laser.

Träbert, Elmar

2014-01-01

97

Measurement of the Lifetime Difference between Bs Mass Eigenstates  

Microsoft Academic Search

We present measurements of the lifetimes and polarization amplitudes for B0s-->J\\/psivarphi and B0d-->J\\/psiK*0 decays. Lifetimes of the heavy and light mass eigenstates in the B0s system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203ą15 B0s decays we obtain tauL=(1.05+0.16-0.13ą0.02) ps and tauH=(2.07+0.58-0.46ą0.03)

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

2005-01-01

98

A measurement of B + and B 0 lifetimes using events  

Microsoft Academic Search

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

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

1995-01-01

99

Measuring Luminescence Lifetime With Help of a DSP  

NASA Technical Reports Server (NTRS)

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

Danielson, J. D. S.

2009-01-01

100

Measurement of the average lifetime of b hadrons  

Microsoft Academic Search

The average lifetime of b hadrons has been measured using the L3 detector at LEP, running at &surd;s ~ MZ. A b-enriched sample was obtained from 432538 hadronic Z events collected in 1990 and 1991 by tagging electrons and muons from semileptonic b hadron decays. From maximum likelihood fits to the electron and muon impact parameter distributions, the average b

O. Adriani; M. Aguilar-Benitez; S. P. Ahlen; J. Alcaraz; A. Aloisio; G. Alverson; M. G. Alviggi; G. Ambrosi; Q. An; H. Anderhub; A. L. Anderson; V. P. Andreev; T. Angelescu; L. Antonov; D. Antreasyan; P. Arce; A. Arefiev; A G Atamanchuk; T. Azemoon; T. Aziz; P. V. K. S. Baba; P. Bagnaia; J. A. Bakken; R. C. Ball; S. Banerjee; J. Bao; R. Barillčre; L. Barone; A. Baschirotto; R. Battiston; A. Bay; F. Becattini; J. Bechtluft; R. Becker; U. Becker; F. Behner; J. Behrens; Gy. L. Bencze; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; M. Biasini; A. Biland; G. M. Bilei; R. Bizzarri; J. J. Blaising; Gerjan J Bobbink; R K Böck; A. Böhm; B. Borgia; M. Bosetti; D. Bourilkov; Maurice Bourquin; D. Boutigny; B T Bouwens; Elena Brambilla; J. G. Branson; I. C. Brock; M. Brooks; A T Bujak; J. D. Burger; W. J. Burger; J K Busenitz; A O Buytenhuijs; X. D. Cai; M. Capell; M. Caria; G. Carlino; A. M. Cartacci; R. Castello; M Cerrada-Canales; F. Cesaroni; Y. H. Chang; U. K. Chaturvedi; M. Chemarin; A. Chen; C. Chen; G. Chen; H. F. Chen; H. S. Chen; W. Y. Chen; G. Chiefari; C. Y. Chien; M. T. Choi; S. Chung; C. Civinini; I. Clare; R. Clare; T. E. Coan; H. O. Cohn; G. Coignet; N. Colino; A. Contin; S. Costantini; F. Cotorobai; X. T. Cui; X. Y. Cui; T. S. Dai; R. D'Alessandro; R. de Asmundis; A. Degré; K. Deiters; E. Dénes; P. Denes; F. Denotaristefani; M. Dhina; D. Dibitonto; M. Diemoz; H. R. Dimitrov; C. Dionisi; M. Ditmarr; L. Djambazov; M. T. Dova; E. Drago; D. Duchesneau; P. Duinker; I. Duran; S. Easo; H. El Mamouni; A. Engler; F. J. Eppling; F. C. Erné; P. Extermann; R. Fabbretti; M. Fabre; S. Falciano; S. J. Fan; O. Fackler; J. Fay; M. Felcini; T. Ferguson; D. Fernandez; G. Fernandez; F. Ferroni; H. Fesefeldt; E. Fiandrini; J. H. Field; F. Filthaut; P. H. Fisher; G. Forconi; L. Fredj; K. Freudenreich; W. Friebel; M. Fukushima; M. Gailloud; Yu. Galaktionov; E. Gallo; S. N. Ganguli; P. Garcia-Abia; D. Gele; S. Gentile; N. Gheordanescu; S Goldfarb; Z. F. Gong; E. Gonzalez; A. Gougas; D. Goujon; G. Gratta; M. Gruenewald; C. Gu; M. Guanziroli; J. K. Guo; V. K. Gupta; A. Gurtu; H. R. Gustafson; L. J. Gutay; K. Hangarter; B. Hartmann; A. Hasan; D. Hauschildt; C. F. He; J. T. He; T. Hebbeker; M. Hebert; A. Hervé; K. Hilgers; H Hoorani; G Q Hu; B. Ille; M. M. Ilyas; V. Innocente; H. Janssen; S. Jezequel; B. N. Jin; L. W. Jones; I. Josa-Mutuberria; A. Kasser; R. A. Khan; Yu. Kamyshkov; P. Kapinos; J. S. Kapustinsky; Y. Karyotakis; M. Kaur; S. Khokhar; M. N. Kienzle-Focacci; J. K. Kim; S. C. Kim; Y. G. Kim; W. W. Kinnison; A. Kirkby; D. Kirkby; S. Kirsch; W. Kittel; A. Klimentov; R. Klöckner; A. C. König; E. Koffeman; O. Kornadt; V. Koutsenko; A. Koulbardis; R. W. Kraemer; T. Kramer; V. R. Krastev; W. Krenz; A. Krivshich; H. Kuijten; K. S. Kumar; A. Kunin; G. Landi; D. Lanske; S. Lanzano; A. Lebedev; P Lecomte; P. Lecoq; P. Le Coultre; D. M. Lee; J. S. Lee; K. Y. Lee; I. Leedom; C. Leggett; J. M. Le Goff; R. Leiste; M. Lenti; E. Leonardi; C. Li; H. T. Li; P. J. Li; J. Y. Liao; W. T. Lin; Z. Y. Lin; F. L. Linde; B. Lindemann; L. Lista; Y. Liu; W. Lohmann; E. Longo; Y. S. Lu; J. M. Lubbers; K. Lübelsmeyer; C. Luci; D. Luckey; L. Ludovici; L. Luminari; W. Lustermann; J. M. Ma; W. G. Ma; M. MacDermott; R. Malik; A. Malinin; C. Mańa; M. Maolinbay; P. Marchesini; F. Marion; A. Marin; J. P. Martin; L. Martinez-Laso; F. Marzano; G. G. G. Massaro; K. Mazumdar; P. McBride; T. McMahon; D. McNally; M. Merk; L. Merola; M. Meschini; W. J. Metzger; Y. Mi; A. Mihul; G. B. Mills; Y. Mir; G. Mirabelli; J. Mnich; M. Möller; B. Monteleoni; R. Morand; S. Morganti; N. E. Moulai; R. Mount; S. Müller; A. Nadtochy; E. Nagy; M. Napolitano; F. Nessi-Tedaldi; H. Newman; C. Neyer; M. A. Niaz; A. Nippe; H. Nowak; G. Organtini; D. Pandoulas; S. Paoletti; P. Paolucci; G Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; Y. J. Pei; S. Pensotti; D. Perret-Gallix; J. Perrier; A. Pevsner; D. Piccolo; M. Pieri; P. A. Piroué; F. Plasil; V. Plyaskin; M. Pohl; V. Pojidaev; H. Postema; Z. D. Qi; J. M. Qian; K. N. Qureshi; R. Raghavan; G. Rahal-Callot; P. G. Rancoita; M. Rattaggi; G. Raven; P. Razis; K. Read; D. Ren; Z. Ren; M. Rescigno; S. Reucroft; A. Ricker; S. Riemann; B. C. Riemers; K. Riles; O. Rind; H. A. Rizvi; S. Ro; F. J. Rodriguez; B. P. Roe; M. Röhner; L. Romero; S. Rosier-Lees; R. Rosmalen; Ph. Rosselet; W. van Rossum; S. Roth; A. Rubbia; J. A. Rubio; H. Rykaczewski; M. Sachwitz; J M Salicio; G. S. Sanders; A. Santocchia; M. S. Sarakinos; G. Sartorelli; M. Sassowsky; G. Sauvage; V. Schegelsky; D. Schmitz; P. Schmitz; M. Schneegans; H. Schopper; D. J. Schotanus; S. Shotkin; H. J. Schreiber; J. Shukla; R. Schulte; S. Schulte; K. Schultze; J. Schwenke; G. Schwering; C. Sciacca; I. Scott; R. Sehgal; P. G. Seiler; J. C. Sens; L. Servoli; I. Sheer; D. Z. Shen; S. Shevchenko; X. R. Shi; E. Shumilov; V. Shoutko

1993-01-01

101

The Development of Plunger Device for Lifetime Measurements in Ciae  

NASA Astrophysics Data System (ADS)

The lifetime knowledge of a nuclear state provides the essential information on transition probabilities for comparison with theoretical nuclear models. A well-known method for picosecond lifetime measurements of excited nuclear states is Recoil Distance Doppler Shift (RDDS) method. Correspondingly a new plunger based on this technique has been developing in CIAE. We use CAD software and Labview to finish the plunger model design and develop a closed control software. A series of methods such as capacitance method, new skills to flatten the foils etc. are applied in building this plunger. Some tests and the latest results with motion and finite element analysis simulations are discussed in this report.

Wang, J. L.; Wu, X. G.; He, C. Y.; Wu, Y. H.; Li, G. S.; Zheng, Y.; Li, C. B.; Yao, S. H.; Hu, S. P.; Li, H. W.; Liu, J. J.

2013-11-01

102

Measurement of the B+ and B0 meson lifetimes  

NASA Astrophysics Data System (ADS)

The lifetimes of the B+ and B0 mesons have been measured using fully reconstructed decays. In a sample of ~49 600J/?-->?+?- 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 ?+=1.61+/-0.16 (stat)+/-0.05 (syst) ps, ?0=1.57+/-0.18 (stat) +/-0.08 (syst) ps, and ?+/?0=1.02+/-0.16 (stat) +/-0.05 (syst).

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

1994-05-01

103

Measurement of the effective Bs0?K+K- lifetime  

NASA Astrophysics Data System (ADS)

A precise determination of the effective Bs0?K+K- lifetime can be used to constrain contributions from physics beyond the Standard Model in the Bs0 meson system. Conventional approaches select B meson decay products that are significantly displaced from the B meson production vertex. As a consequence, B mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb of data recorded by the LHCb experiment, the effective Bs0?K+K- lifetime is measured as 1.455ą0.046 (stat.)ą0.006 (syst.) ps.

Aaij, R.; Abellan Beteta, C.; Adametz, A.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amhis, Y.; Anderson, J.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Bachmann, S.; Back, J. J.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bates, A.; Bauer, C.; Bauer, Th.; Bay, A.; Beddow, J.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Benayoun, M.; Bencivenni, G.; Benson, S.; Benton, J.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjřrnstad, P. M.; Blake, T.; Blanc, F.; Blanks, C.; Blouw, J.; Blusk, S.; Bobrov, A.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Büchler-Germann, A.; Burducea, I.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cattaneo, M.; Cauet, Ch.; 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.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D.; Currie, R.; D'Ambrosio, C.; David, P.; David, P. N. Y.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Degaudenzi, H.; Del Buono, L.; Deplano, C.; Derkach, D.; Deschamps, O.; Dettori, F.; Dickens, J.; Dijkstra, H.; Diniz Batista, P.; Domingo Bonal, F.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisele, F.; Eisenhardt, S.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Elsby, D.; Esperante Pereira, D.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Fave, V.; Fernandez Albor, V.; Ferro-Luzzi, M.; Filippov, S.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furcas, S.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garnier, J.-C.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gauvin, N.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gibson, V.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Harrison, P. F.; Hartmann, T.; He, J.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Hicks, E.; Hoballah, M.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Huston, R. S.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Ilten, P.; Imong, J.; Jacobsson, R.; Jaeger, A.; Jahjah Hussein, M.; Jans, E.; Jansen, F.; Jaton, P.; Jean-Marie, B.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Jost, B.; Kaballo, M.; Kandybei, S.; Karacson, M.; Karbach, T. M.; Keaveney, J.; Kenyon, I. R.; Kerzel, U.; Ketel, T.; Keune, A.; Khanji, B.; Kim, Y. M.; Knecht, M.; 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.; Kruzelecki, K.; 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.; Lefčvre, R.; Leflat, A.; Lefrançois, J.; Leroy, O.; Lesiak, T.; Li, L.; Li, Y.; Li Gioi, L.; Lieng, M.; Liles, M.; Lindner, R.; Linn, C.; Liu, B.; Liu, G.; von Loeben, J.; Lopes, J. H.; Lopez Asamar, E.; Lopez-March, N.; Lu, H.; Luisier, J.; Mac Raighne, A.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Magnin, J.; Malde, S.; Mamunur, R. M. D.; Manca, G.; Mancinelli, G.; Mangiafave, N.; Marconi, U.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Martin, L.; Martín Sánchez, A.; Martinelli, M.; Martinez Santos, D.; Massafferri, A.; Mathe, Z.; Matteuzzi, C.; Matveev, M.

2012-10-01

104

Measurement of the effective Bs0?K+K- lifetime  

NASA Astrophysics Data System (ADS)

A precise determination of the effective Bs0?K+K- lifetime can be used to constrain contributions from physics beyond the Standard Model in the Bs0 meson system. Conventional approaches select B meson decay products that are significantly displaced from the B meson production vertex. As a consequence, B mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb of data recorded by the LHCb experiment, the effective Bs0?K+K- lifetime is measured as 1.455ą0.046(stat.)ą0.006(syst.)ps.

LHCb Collaboration; Aaij, R.; Abellan Beteta, C.; Adametz, A.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amhis, Y.; Anderson, J.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Bachmann, S.; Back, J. J.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bates, A.; Bauer, C.; Bauer, Th.; Bay, A.; Beddow, J.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Benayoun, M.; Bencivenni, G.; Benson, S.; Benton, J.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjřrnstad, P. M.; Blake, T.; Blanc, F.; Blanks, C.; Blouw, J.; Blusk, S.; Bobrov, A.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Büchler-Germann, A.; Burducea, I.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cattaneo, M.; Cauet, Ch.; 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.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D.; Currie, R.; D'Ambrosio, C.; David, P.; David, P. N. Y.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Degaudenzi, H.; Del Buono, L.; Deplano, C.; Derkach, D.; Deschamps, O.; Dettori, F.; Dickens, J.; Dijkstra, H.; Diniz Batista, P.; Domingo Bonal, F.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisele, F.; Eisenhardt, S.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Elsby, D.; Esperante Pereira, D.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Fave, V.; Fernandez Albor, V.; Ferro-Luzzi, M.; Filippov, S.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furcas, S.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garnier, J.-C.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gauvin, N.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gibson, V.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Harrison, P. F.; Hartmann, T.; He, J.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Hicks, E.; Hoballah, M.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Huston, R. S.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Ilten, P.; Imong, J.; Jacobsson, R.; Jaeger, A.; Jahjah Hussein, M.; Jans, E.; Jansen, F.; Jaton, P.; Jean-Marie, B.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Jost, B.; Kaballo, M.; Kandybei, S.; Karacson, M.; Karbach, T. M.; Keaveney, J.; Kenyon, I. R.; Kerzel, U.; Ketel, T.; Keune, A.; Khanji, B.; Kim, Y. M.; Knecht, M.; 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.; Kruzelecki, K.; 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.; Lefčvre, R.; Leflat, A.; Lefrançois, J.; Leroy, O.; Lesiak, T.; Li, L.; Li, Y.; Li Gioi, L.; Lieng, M.; Liles, M.; Lindner, R.; Linn, C.; Liu, B.; Liu, G.; von Loeben, J.; Lopes, J. H.; Lopez Asamar, E.; Lopez-March, N.; Lu, H.; Luisier, J.; Mac Raighne, A.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Magnin, J.; Malde, S.; Mamunur, R. M. D.; Manca, G.; Mancinelli, G.; Mangiafave, N.; Marconi, U.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Martin, L.; Martín Sánchez, A.; Martinelli, M.; Martinez Santos, D.; Massafferri, A.; Mathe, Z.; Matteuzzi, C.

2012-10-01

105

Inhomogeneous dephasing masks coherence lifetimes in ensemble measurements  

SciTech Connect

An open question at the forefront of modern physical sciences is what role, if any, quantum effects may play in biological sensing and energy transport mechanisms. One area of such research concerns the possibility of coherent energy transport in photosynthetic systems. Spectroscopic evidence of long-lived quantum coherence in photosynthetic light-harvesting pigment protein complexes (PPCs), along with theoretical modeling of PPCs, has indicated that coherent energy transport might boost efficiency of energy transport in photosynthesis. Accurate assessment of coherence lifetimes is crucial for modeling the extent to which quantum effects participate in this energy transfer, because such quantum effects can only contribute to mechanisms proceeding on timescales over which the coherences persist. While spectroscopy is a useful way to measure coherence lifetimes, inhomogeneity in the transition energies across the measured ensemble may lead to underestimation of coherence lifetimes from spectroscopic experiments. Theoretical models of antenna complexes generally model a single system, and direct comparison of single system models to ensemble averaged experimental data may lead to systematic underestimation of coherence lifetimes, distorting much of the current discussion. In this study, we use simulations of the Fenna-Matthews-Olson complex to model single complexes as well as averaged ensembles to demonstrate and roughly quantify the effect of averaging over an inhomogeneous ensemble on measured coherence lifetimes. We choose to model the Fenna-Matthews-Olson complex because that system has been a focus for much of the recent discussion of quantum effects in biology, and use an early version of the well known environment-assisted quantum transport model to facilitate straightforward comparison between the current model and past work. Although ensemble inhomogeneity is known to lead to shorter lifetimes of observed oscillations (simply inhomogeneous spectral broadening in the time domain), this important fact has been left out of recent discussions of spectroscopic measurements of energy transport in photosynthesis. In general, these discussions have compared single-system theoretical models to whole-ensemble laboratory measurements without addressing the effect of inhomogeneous dephasing. Our work addresses this distinction between single system and ensemble averaged observations, and shows that the ensemble averaging inherent in many experiments leads to an underestimation of coherence lifetimes in individual systems.

Pelzer, Kenley M.; Griffin, Graham B.; Engel, Gregory S. [James Franck Institute and Department of Chemistry, University of Chicago, Chicago, Illinois 60637 (United States); Gray, Stephen K. [Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2012-04-28

106

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

107

Precision measurement of the Lambda_b baryon lifetime  

E-print Network

The ratio of the \\Lambda b baryon lifetime to that of the B0 meson is measured using 1.0/fb of integrated luminosity in 7 TeV center-of-mass energy pp collisions at the LHC. The \\Lambda b baryon is observed for the first time in the decay mode \\Lambda b -> J/\\psi pK-, while the B0 meson decay used is the well known B0 -> J/\\psi pi+K- mode, where the pi+ 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 B0 meson lifetime, the \\Lambda b lifetime is found to be 1.482 +/- 0.018 +/- 0.012 ps. In both cases the first uncertainty is statistical and the second systematic.

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

2013-07-31

108

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

109

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

110

Simulations of <1 0 0> edge and 1/2<1 1 1> screw dislocations in ?-iron and tungsten and positron lifetime calculations  

NASA Astrophysics Data System (ADS)

Dislocations in BCC metals are of crucial importance for understanding behavior of fusion materials. In this study model positron lifetime quantum-mechanical calculations have been carried out in the two-component density functional theory (DFT) in local density approximation (LDA) for perfect iron and tungsten lattices, lattices with <1 0 0> edge and 1/2<1 1 1> screw dislocations and several cases in which dislocations interact with a vacancy, bi-vacancy and vacancies containing hydrogen or helium atoms. The core structures of the dislocations have been obtained by MD-simulations using Mendelev and Ackland potentials for iron and Finnis-Sinclair potential for tungsten. The calculated values for iron are 153 ps for edge dislocation and 124 ps for screw dislocation, while for tungsten are 161 and 130 ps, respectively. We report new results for screw dislocation showing that minor dilation of the lattice volume associated with second-order elasticity theory influences the calculated positron lifetime.

Staikov, P.; Djourelov, N.

2013-03-01

111

Measurement of the Lambdab0 lifetime using semileptonic decays.  

PubMed

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

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

2007-11-01

112

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

113

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 ą 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

114

A measurement of the Lambda0b lifetime  

Microsoft Academic Search

The lifetime of the Lambda0b baryon has been measured using 3.6 million hadronic Z0 decays recorded by the OPAL detector at LEP from 1990 to 1994. A sample of Lambda0b decays is obtained using partially reconstructed semileptonic decays involving Lambda+cl- combinations, where the Lambda+c is reconstructed from its decay to a pK-pi+ final state. From the 69 +\\/- 13 Lambda+cl-

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; S. Bethke; A. Beck; G. A. Beck; C. Beeston; T. Behnke; K. W. Bell; G. Bella; S. Bentvelsen; P. Berlich; J. Bechtluft; O. Biebel; I. J. Bloodworth; P. Bock; H. M. Bosch; M. Boutemeur; S. Braibant; P. Bright-Thomas; R. M. Brown; A. Buijs; H. J. Burckhart; R. Bürgin; C. Burgard; 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; 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; J. Goldberg; D. M. Gingrich; 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; D. Karlen; J. Kanzaki; 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; X. C. Lou; 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; P. Schütz; M. Schulz; 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

115

Measurement of the lifetime of b-baryons  

Microsoft Academic Search

The average lifetime of weakly decaying b-baryons was studied using 3.6 million Z0 hadronic decays collected by the DELPHI detector at LEP. The measurement of the proper decay time distribution of secondary vertices was used on three complementary samples. The first sample consisted of events with a fully reconstructed Lambda c+ and an opposite charge lepton, or an oppositely charged

P. Abreu; P Adzic; Z Albrecht; T Alderweireld; G D Alekseev; R Alemany; T Allmendinger; P P Allport; S Almehed; Ugo Amaldi; S Amato; E G Anassontzis; P Andersson; A Andreazza; S Andringa; P Antilogus; W D Apel; Y Arnoud; B Ĺsman; J E Augustin; A Augustinus; Paul Baillon; P Bambade; F Barăo; Guido Barbiellini; R Barbier; Dimitri Yuri Bardin; G Barker; A Baroncelli; Marco Battaglia; M Baubillier; K H Becks; M Begalli; P Beilličre; Yu A Belokopytov; K S Belous; Alberto C Benvenuti; C Bérat; M Berggren; D Bertini; D Bertrand; M Besançon; F Bianchi; M Bigi; S M Bilenky; M A Bizouard; D Bloch; H M Blom; M Bonesini; W Bonivento; M Boonekamp; P S L Booth; A W Borgland; G Borisov; C Bosio; O Botner; E Boudinov; B Bouquet; C Bourdarios; T J V Bowcock; I Boyko; I Bozovic; M Bozzo; P Branchini; T Brenke; R A Brenner; P Brückman; J M Brunet; L Bugge; T Buran; T Burgsmüller; P Buschmann; S Cabrera; M Caccia; M Calvi; T Camporesi; V Canale; F Carena; L Carroll; Carlo Caso; M V Castillo-Gimenez; A Cattai; F R Cavallo; V Chabaud; M M Chapkin; P Charpentier; L Chaussard; P Checchia; G A Chelkov; R Chierici; P V Chliapnikov; P Chochula; V Chorowicz; J Chudoba; K Cieslik; P Collins; R Contri; E Cortina; G Cosme; F Cossutti; J H Cowell; H B Crawley; D J Crennell; S Crépé; G Crosetti; J Cuevas-Maestro; S Czellar; Martyn Davenport; W Da Silva; A Deghorain; G Della Ricca; P A Delpierre; N Demaria; A De Angelis; Wim de Boer; S De Brabandere; C De Clercq; B De Lotto; A De Min; L S De Paula; H Dijkstra; Lucia Di Ciaccio; J Dolbeau; K Doroba; M Dracos; J Drees; M Dris; A Duperrin; J D Durand; G Eigen; T J C Ekelöf; Gösta Ekspong; M Ellert; M Elsing; J P Engel; B Erzen; M C Espirito-Santo; E Falk; G K Fanourakis; D Fassouliotis; J Fayot; Michael Feindt; A Fenyuk; P Ferrari; A Ferrer; E Ferrer-Ribas; S Fichet; A Firestone; U Flagmeyer; H Föth; E Fokitis; F Fontanelli; B J Franek; A G Frodesen; R Frühwirth; F Fulda-Quenzer; J A Fuster; A Galloni; D Gamba; S Gamblin; M Gandelman; C García; C Gaspar; M Gaspar; U Gasparini; P Gavillet; E N Gazis; D Gelé; N Ghodbane; I Gil; F Glege; R Gokieli; B Golob; G Gómez-Ceballos; P Gonçalves; I González-Caballero; Gian P Gopal; L Gorn; M Górski; Yu Guz; Valerio Gracco; J Grahl; E Graziani; C Green; H J Grimm; P Gris; G Grosdidier; K Grzelak; M Günther; J Guy; F Hahn; S Hahn; S Haider; A Hallgren; K Hamacher; J Hansen; F J Harris; V Hedberg; S Heising; J J Hernández; P Herquet; H Herr; T L Hessing; J M Heuser; E Higón; S O Holmgren; P J Holt; S Hoorelbeke; M A Houlden; Josef Hrubec; K Huet; G J Hughes; K Hultqvist; J N Jackson; R Jacobsson; P Jalocha; R Janik; C Jarlskog; G Jarlskog; P Jarry; B Jean-Marie; E K Johansson; P E Jönsson; C Joram; P Juillot; F Kapusta; K Karafasoulis; S Katsanevas; E C Katsoufis; R Keränen; Borut P Kersevan; B A Khomenko; N N Khovanskii; A P Kiiskinen; B J King; A Kinvig; N J Kjaer; O Klapp; H Klein; P M Kluit; P Kokkinias; M Koratzinos; V Kostyukhin; C Kourkoumelis; O Kuznetsov; Manfred Krammer; E Kriznic; J Krstic; Z Krumshtein; P Kubinec; J Kurowska; K L Kurvinen; J Lamsa; P Langefeld; V Lapin; J P Laugier; R Lauhakangas; Gerhard Leder; F Ledroit; V Lefébure; L Leinonen; A Leisos; R Leitner; J Lemonne; Georg Lenzen; V Lepeltier; T Lesiak; M Lethuillier; J Libby; D Liko; A Lipniacka; I Lippi; B Lörstad; J G Loken; J H Lopes; J M López; R López-Fernandez; D Loukas; P Lutz; L Lyons; J N MacNaughton; J R Mahon; A Maio; A Malek; T G M Malmgren; V Malychev; J Marco; R P Marco; B Maréchal; M Margoni; J C Marin; C Mariotti; A Markou; C Martínez-Rivero; F Martínez-Vidal; S Martí i García; J Masik; N Mastroyiannopoulos; F Matorras; C Matteuzzi; Giorgio Matthiae; F Mazzucato; M Mazzucato; M L McCubbin; R McKay; R McNulty; G McPherson; C Meroni; W T Meyer; E Migliore; L Mirabito; Winfried A Mitaroff; U Mjörnmark; T Moa; M Moch; R Mřller; K Mönig; M R Monge; X Moreau; P Morettini; G A Morton; U Müller; K Münich; M Mulders; C Mulet-Marquis; R Muresan; W J Murray; B Muryn; Gerald Myatt; T Myklebust; F Naraghi; Francesco Luigi Navarria; S Navas; K Nawrocki; P Negri; S Némécek; N Neufeld; N Neumeister; R Nicolaidou; B S Nielsen; M Nikolenko; V P Nomokonov; Ainsley Normand; A Nygren; V F Obraztsov; A G Olshevskii; A Onofre; Risto Orava; G Orazi; K Österberg; A Ouraou; M Paganoni; S Paiano; R Pain; R Paiva; J Palacios; H Palka; T D Papadopoulou; K Papageorgiou; L Pape; C Parkes; F Parodi; U Parzefall; A Passeri; O Passon; M Pegoraro; L Peralta; Manfred Pernicka; A Perrotta; C Petridou; A Petrolini; H T Phillips; F Pierre; M Pimenta; E Piotto; T Podobnik; M E Pol; G Polok; P Poropat; V Pozdnyakov; P Privitera; N Pukhaeva; Antonio Pullia; D Radojicic; S Ragazzi; H Rahmani; D Rakoczy; P N Ratoff; A L Read; P Rebecchi; N G Redaelli; Meinhard Regler; D Reid; R Reinhardt; P B Renton; L K Resvanis; F Richard; J Rídky; G Rinaudo; O M Rřhne; A Romero

1999-01-01

116

Positron States in Si1-xGex Alloys  

NASA Astrophysics Data System (ADS)

Electron-positron momentum densities along different crystallographic directions and positron bulk lifetime in Si1-xGex alloys have been investigated within the pseudopotential formalism employing the independent particle model. Special attention has been given to the effect of the deviation of the alloy lattice parameters from Vegard's rule on the studied quantities. It is found that using Vegard's law leads to an underestimation of the total positron annihilation rate indicating therefore an overestimation of the positron bulk lifetime. This result could not be checked using the Siethoff relation (H. Siethoff, Phys. Stat. Sol. B205, R3 (1998)). Moreover, this relation predicts a monotonic dependence of the positron bulk lifetime on the alloy composition which disagrees with the positron lifetime measurement.

Bouarissa, N.

117

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

118

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

119

Positron annihilation lifetime spectroscopy (PALS) and small angle x-ray scattering (SAXS) of self-assembled amphiphiles  

NASA Astrophysics Data System (ADS)

Self-assembled amphiphile systems are utilized in a wide variety of applications including drug delivery and energy storage. Nano-scale physical and chemical interactions govern the packing of self-assembled amphiphilic molecules, resulting in thermodynamically stable phases of defined geometries. Possible phases include micellar, hexagonal, cubic, lamellar and sponge phases. The internal nano-structure of the amphiphile self assembly materials play an important role in the properties of these systems and their application. To date small angle x-ray scattering (SAXS) has been the most common technique used to characterise their structure. Positron annihilation lifetime spectroscopy (PALS) offers a possible alternative technique as it is sensitive to both the internal cavities and the intermolecular forces and in combination with SAXS, may provide more detailed structural information such as trends with composition and temperature variations. The phase behaviour of a bulk phytantriol sample, consisting of 33 % w/w water was explored using PALS, and it was found that PALS was sensitive to phase transitions from bicontinuous cubic (Pn3m) to reversed hexagonal (H II) to reversed micellar (L II) phases. These boundaries agreed well with SAXS data. Trends observed for the PALS parameters ?3 and I3 as a function of temperature largely supports the concept that the ortho-positronium is annihilating in the organic regions of the self-assembled structure. However, further investigation is required. We have also developed an innovative data analysis technique to analyse PALS spectra for pore information, with the aim of minimising operator bias and error, which leads to better quantitative comparison of PALS results between laboratories.

Dong, Aurelia W.; Pascual-Izarra, Carlos; Dong, Yao-Da; Pas, Steven J.; Hill, Anita J.; Boyd, Ben J.; Drummond, Calum

2007-12-01

120

Lifetime measurements and decay spectroscopy of 132I  

NASA Astrophysics Data System (ADS)

The low-lying states of odd-odd 132I, the 3p-3h nucleus with respect to the doubly magic 132Sn, have been characterized from decay spectroscopy. The neutron rich Iodine and Tellurium isotopes have been produced as fission product of alpha-induced fission of 235U and radiochemically separated. The life-time of the first excited state of 132I have been precisely measured using LaBr3(Ce) scintillators from the decay of 132Te. The IT decay of the high spin isomer (8-) in 132I has been measured with a Low Energy Photon Spectrometer (LEPS) of segmented planar Ge detector.

Bhattacharyya, S.; Banerjee, D.; Das, S. K.; Bhattacharya, Soumik; Das Gupta, S.; Mukherjee, G.; Bhattacharjee, T.; Chowdhury, A.; Das, P.; Guin, R.; Pai, H.

2014-03-01

121

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

122

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

123

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

SciTech Connect

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

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

2014-01-28

124

Measurements of ultracold neutron lifetimes in solid deuterium  

E-print Network

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

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

2001-09-27

125

Drug release profiles and microstructural characterization of cast and freeze dried vitamin B12 buccal films by positron annihilation lifetime spectroscopy.  

PubMed

Solvent cast and freeze dried films, containing the water-soluble vitamin B12 as model drug were prepared from two polymers, sodium alginate (SA), and Carbopol 71G (CP). The proportion of the CP was changed in the films. The microstructural characterization of various samples was carried out by positron annihilation lifetime spectroscopy (PALS). The drug release kinetics of untreated and stored samples was evaluated by the conventionally applied semi-empirical power law. Correlation was found between the changes of the characteristic parameters of the drug release and the ortho-positronium (o-Ps) lifetime values of polymer samples. The results indicated that the increase of CP concentration, the freeze-drying process and the storage at 75% R.H. decreased the rate of drug release. The PALS method enabled the distinction between the micro- and macrostructural factors influencing the drug release profile of polymer films. PMID:24269613

Szabó, Barnabás; Kállai, Nikolett; Tóth, Gerg?; Hetényi, Gergely; Zelkó, Romána

2014-02-01

126

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. 17 figs.

Ahrenkiel, R.K.

1999-07-27

127

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

128

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 is nearing completion at NIST. In our unique approach, a 8.9 Angstrom neutron beam is incident on a superfluid ^4He target within the minimum field region of an Ioffe- type magnetic trap. Some neutrons are downscattered by single phonon emission in the superfluid 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. Statistical limitations of the previous apparatus as well as systematics related to neutron material bottling will be reduced by significant increases in field strength and trap volume. Tests of a new magnetic trap, cryostat, and details of the upgrade will be presented.

Mumm, H. P.; Coakley, K. J.; Thompson, A. K.; Yang, G.; Golub, R.; Huffman, P. R.; O'Shaughnessy, C. M.; Schelhammer, K. W.; Seo, P.; Doyle, J. M.; Yang, L.; Lamoreaux, S. K.

2008-10-01

129

Lifetime measurements and terminating structures in 87Nb  

NASA Astrophysics Data System (ADS)

Two experiments have been performed using the 58Ni(32S,3p) reaction at 135 MeV with Gammasphere and the Microball to study the high-spin structure of the transitional nucleus 87Nb. The first experiment using a thin target provided a considerable extension and refinement of the level scheme, as well as firm spin assignments from directional correlation of oriented nuclei. Sub-picosecond lifetimes were measured in the second backed-target experiment using the Doppler-shift attenuation method. The lifetimes imply a rather modest average deformation of ?2˜0.1, but with considerable variation from state to state. Strong alternations were observed in the B(M1) strengths of transitions between some pairs of bands. The experimental results were compared with calculations performed within the cranked Nilsson-Strutinsky approach. The calculations generally reproduce the irregularities in the structure of the yrast lines and plunging transition quadrupole moments Qt within the bands explaining them as reflections of configuration changes and an approach of band termination, respectively.

Pavan, J.; Tabor, S. L.; Afanasjev, A. V.; Baktash, C.; Cristancho, F.; Devlin, M.; Döring, J.; Gross, C. J.; Johns, G. D.; Kaye, R. A.; Lafosse, D. R.; Lee, I. Y.; Lerma, F.; Macchiavelli, A. O.; Ragnarsson, I.; Sarantites, D. G.; Solomon, G. N.

2003-03-01

130

Lifetime measurement of the first 2+ state in Pt178  

NASA Astrophysics Data System (ADS)

The lifetime of the 21+ state in Pt178 was measured by using fast-timing techniques with the high-purity Ge and LaBr3:Ce array using the Gd154(28Si,4n) reaction at a beam energy of 146 MeV. The deduced B (E2,21+?01+) strength is discussed in relation to the systematics of the previously reported B (E2,21+?01+) strengths in the light even-even 176-184Pt isotopes and compared with calculations of the generator coordinate method. The present results support a configuration-mixing interpretation for low-spin states in these light Pt isotopes.

Li, C. B.; Chen, F. Q.; Wu, X. G.; He, C. Y.; Zheng, Y.; Li, G. S.; Chen, Q. M.; Gao, Z. C.; Xia, Q. L.; Zhou, W. P.; Hu, S. P.; Li, H. W.; Wang, J. L.; Liu, J. J.; Wu, Y. H.; Luo, P. W.

2014-10-01

131

Measuring the Neutron Lifetime Using Magnetically Trapped Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

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 detected via scintillation light of liquid helium due to the decay events. The advantages of this technique are the continuous detection of the decay events and the elimination of trap losses due to interactions with a material wall potential. Current work is aimed at upgrading the experiment to include a larger and deeper magnetic trap. This is expected to reduce the statistical uncertainties to 1-3 s. Here the apparatus upgrades will be discussed.

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

2007-10-01

132

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

E-print Network

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

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

2014-03-04

133

The influence of microstructure on the sintering process in crystalline metal powders investigated by positron lifetime spectroscopy: III. Nickel reduction powder  

NASA Astrophysics Data System (ADS)

The sintering process in compacts of nickel reduction powder is investigated by positron lifetime spectroscopy. Additionally, the lifetime data obtained are compared to the data on the recovery and recrystallization after plastic deformation caused by cold rolling or pressing, and on the annealing out of vacancy clusters caused by low-temperature electron irradiation. Due to the small grain sizes inside the powder particles at lower temperature, positrons annihilate at grain boundaries, leading to vacancy-cluster-like signals. At intermediate temperature, a surface signal is detected 0953-8984/11/7/011/img7. This is in agreement with an effective powder-particle size of 0953-8984/11/7/011/img8 estimated from scanning electron microscopy. When sintering starts, i.e. above 0953-8984/11/7/011/img9, the only detected defect signal, besides a small surface signal, stems from large-angle grain boundaries. At the intensive-shrinkage stage, there are contributions from different shrinkage mechanisms. The experimentally observed shrinkage rates can be explained by Coble creep which seems to dominate the material transport. Nabarro-Herring and dislocation creep play only minor roles in this system.

Staab, T. E. M.; Krause-Rehberg, R.; Vetter, B.; Kieback, B.

1999-02-01

134

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

SciTech Connect

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

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

2013-12-14

135

Spin Lifetime Measurements of GaAsBi Films  

NASA Astrophysics Data System (ADS)

Substituting a small amount of As with Bi, the largest non-radioactive group V element, leads to a large reduction in the GaAs band gap and expected large spin-orbit effects ootnotetextB. Fluegel et al., Giant Spin-Orbit Bowing in GaAs1-xBix, Phys. Rev. Lett. 97, 067205 (2006).. Both properties are advantageous with potential applications ranging from infrared detectors to spin valves. Compressively strained GaAsBi films with varying bismuth compositions were grown on GaAs using molecular-beam epitaxy. Spin lifetimes were measured using the Hanle effect, a magneto-optical technique where an out-of-plane spin polarization is generated by circularly polarized light and then made to precess about an in-plane magnetic field. A Lorentzian lineshape can be fit to the field-dependent photoluminescence polarization to extract gTs, where g is the Lande g-factor and Ts is a function of the carrier recombination time and spin dephasing time and provides a lower bound for both. Temperature and power dependent measurements were conducted and our extracted values for gTs vary from 100ps to 1ns.

Pursley, Brennan; Vardar, G.; Goldman, R. S.; Sih, V.

2012-02-01

136

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

137

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

138

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

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

139

Positron studies in catalysis research. Final report, September 1993-- May 1995  

SciTech Connect

During the past 20 months, we have completed our positron microscope and performed several studies in our nonmicroscopic depth-profiling positron spectrometer which should ultimately be applicable to catalysis. These studies involve using depth-profiled positron spectrometers to observe the growth dynamics of metal silicides on silicon substrates and to observe defects in glassy polymer surfaces and thin films, and the use of bulk positron lifetime measurements to observe pore-size variations in zeolites.

NONE

1996-05-01

140

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

E-print Network

that simulate thin-film photovoltaic manufacturing environments. National Renewable Energy Laboratory (NREL of conditions in a thin-film photovoltaic (PV) manufacturing line. NREL's work in recent years has demonstrated with minority-carrier lifetime, which can be measured by NREL'sTRPL system. Potential Impact Photovoltaic thin

141

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS01  

Microsoft Academic Search

A measurement of the cosmic ray positron fraction e+\\/(e++e?) in the energy range of 1–30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 106 is reached by identifying converted bremsstrahlung photons emitted from positrons.

M. Aguilar; J. Alcaraz; B. Alpat; G. Ambrosi; H. Anderhub; L. Ao; A. Arefiev; P. Azzarello; L. Baldini; M. Basile; D. Barancourt; F. Barao; G. Barbier; G. Barreira; R. Battiston; U. Becker; L. Bellagamba; P. Béné; J. Berdugo; P. Berges; B. Bertucci; A. Biland; S. Blasko; G. Boella; M. Boschini; L. Brocco; G. Bruni; M. Buénerd; J. D. Burger; W. J. Burger; X. D. Cai; C. Camps; P. Cannarsa; M. Capell; F. Cardano; D. Casadei; J. Casaus; G. Castellini; Y. H. Chang; Y. H. Chang; H. S. Chen; Z. G. Chen; N. A. Chernoplekov; Tzi Hong Chiueh; K. Cho; M. J. Choi; Y. Y. Choi; F. Cindolo; V. Commichau; A. Contin; E. Cortina-Gil; M. Cristinziani; T. S. Dai; C. Delgado; S. Difalco; L. Djambazov; I. D'Antone; Z. R. Dong; P. Emonet; J. Engelberg; F. J. Eppling; T. Eronen; G. Esposito; P. Extermann; Jean Favier; E. Fiandrini; P. H. Fisher; G. Flügge; N. Fouque; Yu. Galaktionov; H. Gast; M. Gervasi; P. Giusti; D. Grandi; O. Grimm; W. Q. Gu; K. Hangarter; A. Hasan; V. Hermel; H. Hofer; W. Hungerford; M. Jongmanns; K. Karlamaa; W. Karpinski; G. Kenney; D. H. Kim; G. N. Kim; K. S. Kim; M. Y. Kim; A. Klimentov; R. Kossakowski; A. Kounine; V F Koutsenko; M. Kraeber; G. Laborie; T. Laitinen; G. Lamanna; E. Lanciotti; G. Laurenti; A. Lebedev; C. Lechanoine-Leluc; M. W. Lee; S. C. Lee; G. Levi; C. L. Liu; H. T. Liu; G. Lu; Y. S. Lu; K. Lübelsmeyer; D. Luckey; W. Lustermann; C. Mańa; A. Margotti; F. Mayet; R. R. McNeil; B. Meillon; M. Menichelli; A. Mihul; A. Mujunen; A. Oliva; J. Olzem; F. Palmonari; H. B. Park; W. H. Park; M. Pauluzzi; F. Pauss; E. Perrin; A. Pesci; A. Pevsner; F. Pilo; M. Pimenta; V. Plyaskin; V Pozhidaev; M. Pohl; N. Produit; P. G. Rancoita; D. Rapin; F. Raupach; D. Ren; Z. Ren; M. Ribordy; J. P. Richeux; E. Riihonen; J. Ritakari; S. Ro; U. Roeser; C. Rossin; R. Sagdeev; D. Santos; G. Sartorelli; C. Sbarra; S. Schael; A. Schultz von Dratzig; G. Schwering; E. S. Seo; J. W. Shin; E. Shoumilov; V. Shoutko; T. Siedenburg; R. Siedling; D. Son; T. Song; F. Spinella; M. Steuer; G. S. Sun; H. Suter; X. W. Tang; Samuel C. C. Ting; S. M. Ting; M. Tornikoski; J. Torsti; J. Trümper; J. Ulbricht; S. Urpo; E. Valtonen; J. Vandenhirtz; E P Velikhov; B. Verlaat; I Vetlitskii; F. Vezzu; J. P. Vialle; G. Viertel; D. Vité; H. Von Gunten; S. Waldmeier Wicki; W. Wallraff; B. C. Wang; J. Z. Wang; K. Wiik; C. Williams; S. X. Wu; P. C. Xia; S. Xu; J. L. Yan; J. L. Yan; C. G. Yang; J. Yang; M. Yang; S. W. Ye; Z. Z. Xu; H. Y. Zhang; Z. P. Zhang; D. X. Zhao; Y. Zhou; G. Y. Zhu; W. Z. Zhu; H. L. Zhuang; A. Zichichi; B. Zimmermann; P. Zuccon

2007-01-01

142

Lifetime and diffusion length measurements on silicon material and solar cells  

NASA Technical Reports Server (NTRS)

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

Othmer, S.; Chen, S. C.

1978-01-01

143

Microstructural Characterization of Polymers with Positrons  

NASA Technical Reports Server (NTRS)

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

Singh, Jag J.

1997-01-01

144

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

E-print Network

. John A. Mclntyre The Texas A&M University Positron Emission Tomograph (TAMU PET) detects the gamma rays which are emitted in positron-electron annihilation by using plastic scintillators and optical fibers to code the light given off... to determine the location of a. gamma ray interaction. The efficiency at which a PET detects scintillstions, in part, determines the clarity of the images produced. This detection efficiency was measured for the TAMU PET by determining the number...

Loewer, Wesley Blake

2012-06-07

145

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

Microsoft Academic Search

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

W. W. Moses

1992-01-01

146

Positron annihilation study of the Mg-Zn -Y alloys with long period stacking ordered (LPSO) structures  

NASA Astrophysics Data System (ADS)

The Mg-Zn-Y alloys with long period stacking ordered (LPSO) structures have been studied by positron annihilation lifetime (PAL), coincidence Doppler broadening (CDB) and atom probe tomography (APT). The positron lifetime for all the Mg-Zn-Y alloys is in a range of 221~225 ps, very close to the positron lifetime for pure Mg bulk, 222 ps. Low temperature measurements of the positron lifetime also give no evidence for shallow positron trapping sites in the LPSO phases. The CDB shows that most of the positrons are annihilated with electrons of Mg. These results suggest that sub-nano scale open volumes, which were expected to exist in the Zn/Y enriched layers synchronized with stacking faults of the LPSO phases by the first principles calculations, are not present.

Xu, H. X.; Inoue, K.; Nagai, Y.; Toyama, T.; Matsukawa, Y.; Kuramoto, A.; Egusa, D.; Abe, E.; Ye, B. J.

2013-06-01

147

Study of the MPD detector capabilities for electron-positron pair measurements at the NICA collider  

NASA Astrophysics Data System (ADS)

One of the main tasks of the NICA/MPD physics program is a study of low-mass vector mesons ?, ?, ? by measuring their dileptonic decay channels. In this paper, the current status of simulations of electron-positron pair measurements in MPD is presented and the detector performance for such measurements is discussed.

Vasendina, V.; Jejer, V.; Kolesnikov, V.; Lobastov, S.; Musulmanbekov, G.; Tyapkin, I.; Zinchenko, A.

2013-12-01

148

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

149

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

PubMed Central

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

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

2014-01-01

150

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

151

Study of Co-containing Ni-Mn-Ga by positron annihilation  

NASA Astrophysics Data System (ADS)

Positron annihilation spectroscopy measurements have been carried out in the ferromagnetic shape memory alloy Ni-Mn-Ga-Co. Positron experiments have been performed at room temperature after subsequent isochronal annealing up to 600 °C. Positron lifetime results have been compared with Differential Scanning Analysis experiments performed in the same samples. Experiments show a large variation of the average positron lifetime values with the annealing temperature of the samples, indicating a clear relation between the concentration of vacancies and the properties of the martensitic transformations of these alloys.

Mérida, D.; García, J. A.; Plazaola, F.; Sanchez-Alarcos, V.; Pérez-Landazábal, J. I.; Recarte, V.

2011-01-01

152

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

PubMed

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

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

2009-03-01

153

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

154

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?

Trabert, E

2009-06-01

155

Lifetime Measurements from the K39 (p,gamma)Ca40 Reaction  

Microsoft Academic Search

Lifetime measurements with a Ge(Li) detector have been made for several excited states of Ca40 by the Doppler-shift attenuation method utilizing the K39 (p,gamma)Ca40 reaction. Agreement with results of (p,p'gamma) lifetime measurements is found for levels at 3.904, 5.280, and 6.285 MeV. New lifetime results are reported for levels at 5.615 MeV (>0.8 psec), 7.465 MeV (0.010-0.006+0.005 psec), and 7.562

K. W. Dolan; D. K. McDaniels

1968-01-01

156

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

E-print Network

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

Taylor, Frank E.

157

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

158

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

NASA Astrophysics Data System (ADS)

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

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

2015-01-01

159

Measurement of the K L meson lifetime with the KLOE detector  

Microsoft Academic Search

We present a measurement of the KL lifetime using the KLOE detector. From a sample of ?4×108KSKL pairs following the reaction e+e????KSKL we select ?15×106KL??0?0?0 decays tagged by KS??+?? events. From a fit of the proper time distribution we find ?L=(50.92ą0.17statą0.25syst) ns. This is the most precise measurement of the KL lifetime performed to date.

F. Ambrosino; A. Antonelli; M. Antonelli; C. Bacci; P. Beltrame; G. Bencivenni; S. Bertolucci; C. Bini; C. Bloise; V. Bocci; F. Bossi; D. Bowring; P. Branchini; R. Caloi; P. Campana; G. Capon; T. Capussela; F. Ceradini; S. Chi; G. Chiefari; P. Ciambrone; S. Conetti; E. De Lucia; A. De Santis; P. De Simone; G. De Zorzi; S. Dell'Agnello; A. Denig; A. Di Domenico; C. Di Donato; S. Di Falco; B. Di Micco; A. Doria; M. Dreucci; G. Felici; A. Ferrari; M. L. Ferrer; G. Finocchiaro; C. Forti; P. Franzini; C. Gatti; P. Gauzzi; S. Giovannella; E. Gorini; E. Graziani; M. Incagli; W. Kluge; V. Kulikov; F. Lacava; G. Lanfranchi; J. Lee-Franzini; D. Leone; M. Martini; P. Massarotti; W. Mei; S. Meola; S. Miscetti; M. Moulson; S. Müller; F. Murtas; M. Napolitano; F. Nguyen; M. Palutan; E. Pasqualucci; A. Passeri; V. Patera; F. Perfetto; L. Pontecorvo; M. Primavera; P. Santangelo; E. Santovetti; G. Saracino; B. Sciascia; A. Sciubba; F. Scuri; I. Sfiligoi; T. Spadaro; M. Testa; L. Tortora; P. Valente; B. Valeriani; G. Venanzoni; S. Veneziano; A. Ventura; R. Versaci; G. Xu

2005-01-01

160

Lifetime measurement of the metastable 2 3P 0 state in He-like uranium  

NASA Astrophysics Data System (ADS)

The lifetime of the 2 3P 0 state in He-like uranium has been measured in a beam-foil time-of-flight experiment at the Gesellschaft für Schwerionenforschung accelerator facility with the result ?(2 3P 0) = 58.2(9.5) ps. With the measured lifetime it is possible to derive a value of ?E2sLamb=76.3ą20.6 eV for the n = 2 Lamb shift in uranium.

Toleikis, S.; Manil, B.; Bednarz, G.; Berdermann, E.; Beyer, H. F.; Bosch, F.; Bräuning-Demian, A.; Gumberidze, A.; Indelicato, P.; Kozhuharov, C.; Liesen, D.; Marrus, R.; Mokler, P. H.; Stachura, Z.; Stöhlker, T.; Warczak, A.

2005-07-01

161

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

162

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

PubMed

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

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

2007-10-01

163

Measurement of the ?b Lifetime in the Exclusive Decay ?b?J/??  

NASA Astrophysics Data System (ADS)

We have measured the ?b lifetime using the exclusive decay ?b?J/??, based on 1.2fb-1 of data collected with the D0 detector during 2002 2006. From 171 reconstructed ?b decays, where the J/? and ? are identified via the decays J/???+?- and ??p?, we measured the ?b lifetime to be ?(?b)=1.218-0.115+0.130(stat)ą0.042(syst)ps. We also measured the B0 lifetime in the decay B0?J/?(?+?-)KS0(?+?-) to be ?(B0)=1.501-0.074+0.078(stat)ą0.050(syst)ps, yielding a lifetime ratio of ?(?b)/?(B0)=0.811-0.087+0.096(stat)ą0.034(syst).

Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Aguilo, E.; Ahn, S. H.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Anastasoaie, M.; Ancu, L. S.; Andeen, T.; Anderson, S.; Andrieu, B.; Anzelc, M. S.; Arnoud, Y.; Arov, M.; Arthaud, M.; Askew, A.; Ĺsman, B.; Jesus, A. C. S. Assis; Atramentov, O.; Autermann, C.; Avila, C.; Ay, C.; Badaud, F.; Baden, A.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, P.; Banerjee, S.; Barberis, E.; Barfuss, A.-F.; Bargassa, P.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Beale, S.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Bellavance, A.; Benitez, J. A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Berntzon, L.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Biscarat, C.; Blazey, G.; Blekman, F.; Blessing, S.; Bloch, D.; Bloom, K.; Boehnlein, A.; Boline, D.; Bolton, T. A.; Borissov, G.; Bos, K.; Bose, T.; Brandt, A.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Buchanan, N. J.; Buchholz, D.; Buehler, M.; Buescher, V.; Burdin, S.; Burke, S.; Burnett, T. H.; Buszello, C. P.; Butler, J. M.; Calfayan, P.; Calvet, S.; Cammin, J.; Caron, S.; Carvalho, W.; Casey, B. C. K.; Cason, N. M.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K.; Chan, K. M.; Chandra, A.; Charles, F.; Cheu, E.; Chevallier, F.; Cho, D. K.; Choi, S.; Choudhary, B.; Christofek, L.; Christoudias, T.; Cihangir, S.; Claes, D.; Clément, B.; Clément, C.; Coadou, Y.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Crépé-Renaudin, S.; Cutts, D.; ?wiok, M.; da Motta, H.; Das, A.; Davies, G.; de, K.; de Jong, P.; de Jong, S. J.; de La Cruz-Burelo, E.; de Oliveira Martins, C.; Degenhardt, J. D.; Déliot, F.; Demarteau, M.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Dominguez, A.; Dong, H.; Dudko, L. V.; Duflot, L.; Dugad, S. R.; Duggan, D.; Duperrin, A.; Dyer, J.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Eno, S.; Ermolov, P.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Ford, M.; Fortner, M.; Fox, H.; Fu, S.; Fuess, S.; Gadfort, T.; Galea, C. F.; Gallas, E.; Galyaev, E.; Garcia, C.; Garcia-Bellido, A.; Gavrilov, V.; Gay, P.; Geist, W.; Gelé, D.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Ginther, G.; Gollub, N.; Gómez, B.; Goussiou, A.; Grannis, P. D.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guo, F.; Guo, J.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hadley, N. J.; Haefner, P.; Hagopian, S.; Haley, J.; Hall, I.; Hall, R. E.; Han, L.; Hanagaki, K.; Hansson, P.; Harder, K.; Harel, A.; Harrington, R.; Hauptman, J. M.; Hauser, R.; Hays, J.; Hebbeker, T.; Hedin, D.; Hegeman, J. G.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hensel, C.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hoeth, H.; Hohlfeld, M.; Hong, S. J.; Hooper, R.; Hossain, S.; Houben, P.; Hu, Y.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jakobs, K.; Jarvis, C.; Jesik, R.; Johns, K.; Johnson, C.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Juste, A.; Käfer, D.; Kahn, S.; Kajfasz, E.; Kalinin, A. M.; Kalk, J. M.; Kalk, J. R.; Kappler, S.; Karmanov, D.; Kasper, J.; Kasper, P.; Katsanos, I.; Kau, D.; Kaur, R.; Kaushik, V.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. M.; Khatidze, D.; Kim, H.; Kim, T. J.; Kirby, M. H.; Kirsch, M.; Klima, B.; Kohli, J. M.; Konrath, J.-P.; Kopal, M.; Korablev, V. M.; Kothari, B.; Kozelov, A. V.; Krop, D.; Kryemadhi, A.; Kuhl, T.; Kumar, A.; Kunori, S.; Kupco, A.; Kur?a, T.; Kvita, J.; Lam, D.; Lammers, S.; Landsberg, G.; Lazoflores, J.; Lebrun, P.; Lee, W. M.; Leflat, A.; Lehner, F.; Lellouch, J.; Lesne, V.; Leveque, J.; Lewis, P.; Li, J.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lima, J. G. R.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Liu, Z.; Lobo, L.; Lobodenko, A.; Lokajicek, M.; Lounis, A.; Love, P.; Lubatti, H. J.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madaras, R. J.; Mättig, P.; Magass, C.; Magerkurth, A.; Makovec, N.; Mal, P. K.; Malbouisson, H. B.; Malik, S.; Malyshev, V. L.; Mao, H. S.; Maravin, Y.; Martin, B.; McCarthy, R.; Melnitchouk, A.; Mendes, A.; Mendoza, L.; Mercadante, P. G.; Merkin, M.; Merritt, K. W.; Meyer, A.; Meyer, J.; Michaut, M.; Millet, T.; Mitrevski, J.; Molina, J.; Mommsen, R. K.; Mondal, N. K.; Moore, R. W.; Moulik, T.; Muanza, G. S.; Mulders, M.; Mulhearn, M.; Mundal, O.; Mundim, L.; Nagy, E.; Naimuddin, M.

2007-10-01

164

Frequency domain fluorescence lifetime microwell-plate platform for respirometry measurements  

NASA Astrophysics Data System (ADS)

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

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

2010-04-01

165

Photoconductivity lifetime measurements on HgCdTe using a contactless microwave technique  

SciTech Connect

Photoconductivity lifetime measurements on narrow band-gap HgCdTe thin films and bulk slices using a contactless microwave reflection technique have been demonstrated for the first time. A horn antenna was used to allow cooling of samples to 77 K outside the waveguide and testings of large-size samples. A good agreement was established between lifetime results from the contactless microwave reflection technique and the standard photoconductivity decay method using two ohmic contacts. The feasibility of lifetime mapping by moving the pulsed light beam to different locations on the samples was also demonstrated.

Chen, M.

1988-07-15

166

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

SciTech Connect

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

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

2014-05-15

167

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

168

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

NASA Technical Reports Server (NTRS)

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

Jackson, W. M.

1974-01-01

169

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

2014-04-01

170

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

171

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

172

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

SciTech Connect

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

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

2013-08-21

173

Measuring the neutron lifetime using magnetically trapped neutrons  

NASA Astrophysics Data System (ADS)

The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we successfully demonstrated the trapping of ultracold neutrons in a conservative potential magnetic trap. A major upgrade of the apparatus is nearing completion at the National Institute of Standards and Technology Center for Neutron Research (NCNR). In our approach, a beam of 0.89 nm neutrons is incident on a superfluid 4He target within the minimum field region of an Ioffe-type magnetic trap. A fraction of the neutrons is downscattered in the helium to energies <200 neV, and those in the appropriate spin state become trapped. The inverse process is suppressed by the low phonon density of helium at temperatures less than 200 mK, allowing the neutron to travel undisturbed. When the neutron decays the energetic electron ionizes the helium, producing scintillation light that is detected using photomultiplier tubes. Statistical limitations of the previous apparatus will be alleviated by significant increases in field strength and trap volume resulting in twenty times more trapped neutrons.

O'Shaughnessy, C. M.; Golub, R.; Schelhammer, K. W.; Swank, C. M.; Seo, P.-N.; Huffman, P. R.; Dzhosyuk, S. N.; Mattoni, C. E. H.; Yang, L.; Doyle, J. M.; Coakley, K. J.; Thompson, A. K.; Mumm, H. P.; Lamoreaux, S. K.; McKinsey, D. N.; Yang, G.

2009-12-01

174

Vacancy-type defects in cold-worked iron studied using positron annihilation techniques  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime (PAL) and coincidence Doppler broadening of the annihilation radiation (CDBAR) measurements have been investigated on cold-worked iron with different percentages of a deformation up to 40%. The PAL spectra were analyzed into two lifetime components. The shorter lifetimes were explicitly smaller than the monovacancy lifetimes, which were possibly caused by deformation-induced dislocations and vacancy-impurity complexes. The longer lifetimes showed that, the deformation introduces also larger vacancy clusters (consisting of five to ten vacancies) as a result of a cold-working. The behavior of the S-parameter (extracted from CDBAR) with the rolling deformation was analogous to the mean positron lifetime. It increased at up to 5% rolling deformation and leveled off above this percentage of the rolling deformation. The CDBAR ratio curve with respect to pure iron showed that, above the 5% rolling deformation the nature of the defects trapping the positron changed.

Mohamed, Hamdy F. M.; Kwon, Junhyun; Kim, Yong-Min; Kim, Whungwhoe

2007-05-01

175

Evolution of fission lifetime with temperature: a straightforward measurement by the blocking technique  

SciTech Connect

The blocking patterns in a single crystal have been used to measure fission lifetimes as a function of the excitation energy in the {sup 238}U+{sup 28}Si reactions at 24 A.MeV. The neutron multiplicity measured on 4 {pi} has been used to infer the excitation energy of the fissioning nuclei. The fission lifetimes measured for uranium-like nuclei with temperatures up to 3 MeV are longer than 10{sup -19} s, a much larger value than those inferred from previous measurements by less direct techniques.

Morjean, M.; Galin, J.; Goldenbaum, F.; Lienard, E.; Lott, B.; Peghaire, A.; Perier, Y. [GANIL DSM/CEA, IN2P3/CNRS, BP 5027, 14076 Caen Cedex 5 (France); Chevallier, M.; Dauvergne, D.; Kirsch, R.; Poizat, J. C.; Remillieux, J. [Institut de Physique Nucleaire de Lyon, IN2P3/CNRS, Univ. Cl. Bernard, 43 Bd. 11 Novembre 1918, F-69622 Villeurbanne Cedex (France); Cohen, C.; Prevot, G.; Schmaus, D. [GPS, 2 place Jussieu, 75251 Paris Cedex 05 (France); Dural, J.; Toulemonde, M. [CIRIL, BP 5133, 14040 Caen Cedex (France); Jacquet, D. [Institut de Physique Nucleaire d'Orsay, BP 1, F-91406 Orsay Cedex (France)

1998-02-15

176

Iron detection in crystalline silicon by carrier lifetime measurements for arbitrary injection and doping  

Microsoft Academic Search

An existing technique for accurate measurement of iron in silicon, which was previously restricted to low injection and a narrow doping range, has been extended to arbitrary injection and doping levels. This allows contactless lifetime measurement techniques to be used for very sensitive and rapid iron detection under a wide range of conditions. In addition, an easily measured and unambiguous

D. H. Macdonald; L. J. Geerligs; A. Azzizi

2004-01-01

177

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

NASA Technical Reports Server (NTRS)

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

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

2011-01-01

178

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

Microsoft Academic Search

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

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

1986-01-01

179

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

180

Measurement of the BŻs 0 Meson Lifetime in Ds+?- Decays  

NASA Astrophysics Data System (ADS)

We present a measurement of the ratio of the BŻs 0 meson lifetime, in the flavor-specific decay to Ds+?-, to that of the BŻ 0 meson. The p p collision data used correspond to an integrated luminosity of 1 fb-1 , collected with the LHCb detector, at a center-of-mass energy of 7 TeV. Combining our measured value of 1.010 ą0.010 ą0.008 for this ratio with the known BŻ 0 lifetime, we determine the flavor-specific BŻs 0 lifetime to be ? (BŻs 0)=1.535 ą0.015 ą0.014 ps , where the uncertainties are statistical and systematic, respectively. This is the most precise measurement to date, and is consistent with previous measurements and theoretical predictions.

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

2014-10-01

181

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

NASA Astrophysics Data System (ADS)

We report on measurements of the mass and lifetime of the ?b- baryon using about 1800 ?b- decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0 fb-1 collected by the LHCb experiment. The decays are reconstructed in the ?b-??c0?-, ?c0?p K-K-?+ channel and the mass and lifetime are measured using the ?b0??c+?- mode as a reference. We measure M (?b-)-M (?b0)=178.36 ą0.46 ą0.16 MeV /c2 , (??b-/??b0)=1.089 ą0.026 ą0.011 , where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the ?b- mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations.

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

2014-12-01

182

Precision Measurement of the Mass and Lifetime of the ?_{b}^{-} Baryon.  

PubMed

We report on measurements of the mass and lifetime of the ?_{b}^{-} baryon using about 1800 ?_{b}^{-} decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0??fb^{-1} collected by the LHCb experiment. The decays are reconstructed in the ?_{b}^{-}??_{c}^{0}?^{-}, ?_{c}^{0}?pK^{-}K^{-}?^{+} channel and the mass and lifetime are measured using the ?_{b}^{0}??_{c}^{+}?^{-} mode as a reference. We measure M(?_{b}^{-})-M(?_{b}^{0})=178.36ą0.46ą0.16??MeV/c^{2}, (?_{?_{b}^{-}}/?_{?_{b}^{0}})=1.089ą0.026ą0.011, where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the ?_{b}^{-} mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations. PMID:25541768

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

2014-12-12

183

Measurement of mobility and lifetime of electrons and holes in a Schottky CdTe diode  

NASA Astrophysics Data System (ADS)

We report on the measurement of drift properties of electrons and holes in a CdTe diode grown by the travelling heating method (THM). Mobility and lifetime of both charge carriers has been measured independently at room temperature and fixed bias voltage using charge integration readout electronics. Both electrode sides of the detector have been exposed to a 241Am source in order to obtain events with full contributions of either electrons or holes. The drift time has been measured to obtain the mobility for each charge carrier. The Hecht equation has been employed to evaluate the lifetime. The measured values for ??e/h (mobility-lifetime product) are in agreement with earlier published data.

Arińo-Estrada, G.; Chmeissani, M.; de Lorenzo, G.; Kolstein, M.; Puigdengoles, C.; García, J.; Cabruja, E.

2014-12-01

184

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

NASA Technical Reports Server (NTRS)

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

Singh, Jag. J.

1992-01-01

185

Measurements of the Cosmic-Ray Positron Fraction From 1 to 50 GeV  

E-print Network

Two measurements of the cosmic-ray positron fraction as a function of energy have been made using the High Energy Antimatter Telescope (HEAT) balloon-borne instrument. The first flight took place from Ft. Sumner, New Mexico in 1994, and yielded results above the geomagnetic cutoff energy of 4.5 GeV. The second flight from Lynn Lake, Manitoba in 1995 permitted measurements over a larger energy interval, from 1 GeV to 50 GeV. In this letter we present results on the positron fraction based on data from the Lynn Lake flight, and compare these with the previously published results from the Ft. Sumner flight. The results confirm that the positron fraction does not increase with energy above ~10 GeV, although a small excess above purely secondary production cannot be ruled out. At low energies the positron fraction is slightly larger than that reported from measurements made in the 1960's. This effect could possibly be a consequence of charge dependence in the level of solar modulation.

HEAT Collaboration; S. W. Barwick; E. Schneider; J. J. Beatty; G. A. de Nolfo; A. Bhattacharyya; C. R. Bower; J. A. Musser; C. J. Chaput; S. Coutu; S. McKee; G. Tarle; A. D. Tomasch; J. Knapp; D. M. Lowder; D. Muller; S. P. Swordy; E. Torbet; S. L. Nutter

1997-03-28

186

Study on Defects in H+ion Implanted B2 type Fe-Al Alloy using Slow Positron Beam  

NASA Astrophysics Data System (ADS)

Fe48-at.%Al alloy were implanted with 50 keV H+ ions to the fluence of 3×1016 and 1×1018/cm2 at room temperature. Positron annihilation Doppler broadening and lifetime measurements for these alloys have been carried out using slow positron beam apparatus with an energy range of 0.2 to 30.2 keV. The positron annihilation S-parameter decreased by H+ ion irradiation. Also the positron lifetimes for hydrogen deposited region in the alloy decreased by the irradiation. These results show that implanted H atoms were trapped by vacancy type defects.

Komagata, S.; Kawasuso, A.; Yabuuchi, A.; Maekawa, M.; Batchulun, C.; Yasuda, K.; Ishigami, R.; Kume, K.; Iwase, A.; Hori, F.

187

NBTI Lifetime Prediction and Kinetics at Operation Bias Based on Ultrafast Pulse Measurement  

Microsoft Academic Search

Predicting negative bias temperature instability (NBTI) lifetime can be dangerous since it is difficult to assess its safety margin. The common technique uses gate bias Vg acceleration to reduce the test time, and the data were typically obtained from quasi-DC measurements. Recently, it has been shown that substantial recovery occurs during the quasi-DC measurement, and the suppression of recovery requires

Zhigang Ji; L. Lin; Jian Fu Zhang; Ben Kaczer; Guido Groeseneken

2010-01-01

188

Characterization of defects in (ZnMg)Se compounds by positron annihilation and photoluminescence  

NASA Astrophysics Data System (ADS)

Defect characterization of as-grown Zn1-xMgxSe mixed crystals (0?x<0.6) and the effect of Zn vapor annealing has been studied by positron lifetime and photoluminescence measurements. We obtain both experimental and theoretical evidence that the bulk lifetime of free positrons increases linearly with Mg alloying. The average positron lifetime increases with temperature indicating that both vacancies and negative ions trap positrons. The decompositions of the lifetime spectra show that the vacancy has the characteristic positron lifetime of 325 ps. The comparison with theoretical calculations indicate that the lifetime 325 ps corresponds either to divacancies relaxed inwards or to monovacancies strongly relaxed outwards. We consider the latter identification more likely and attribute the positron lifetime 325 ps to Zn vacancy or a complex involving VZn. The vacancy concentration is almost independent of Mg content above x=0.2 but decreases strongly at x=0.56. The Zn vapor annealing decreases the concentration of Zn vacancies. The intensity of the green photoluminescence correlates with the concentration of VZn both as a function of Mg alloying and Zn vapor annealing. We thus conclude that the electron levels of the Zn vacancy are involved in the optical transition leading to the green photoluminescence.

Plazaola, F.; Saarinen, K.; Dobrzynski, L.; Reniewicz, H.; Firszt, F.; Szatkowski, J.; Meczynska, H.; Legowski, S.; Chabik, S.

2000-08-01

189

Capacitive effects in quasi-steady-state voltage and lifetime measurements of silicon devices  

NASA Astrophysics Data System (ADS)

When measuring I-V characteristics and carrier lifetimes in quasi-steady-state (QSS) conditions, it is important to consider the time dependence of the charge due to excess carriers within the device. This paper shows that the space-charge region present in pn-junction devices and in many lifetime test structures can produce a significant capacitive effect when measuring the low voltage and low carrier density range of QSS I-V curves. Both computer modeling and experiments show that the junction capacitance is particularly significant in the case of low-resistivity silicon wafers, but it can also be noticeable in intermediate and high-resistivity samples. The paper demonstrates that the static I-V characteristics can be accurately reconstructed using a simple analytical model for the space-charge region. It thus fills a gap in the understanding of the low injection range of QSS voltage and lifetime measurements.

Cuevas, A.; Recart, F.

2005-10-01

190

Measurement of the $B_c^{-}$ meson lifetime in the decay $B_{c}^{-} \\rightarrow J/?~?^{-}$  

E-print Network

The lifetime of the $B_c^{-}$ meson is measured using 272 exclusive $B_{c}^{-} \\to J/\\psi (\\to \\mu^+\\mu^-) \\pi^-$ decays reconstructed in data from proton-antiproton collisions corresponding to an integrated luminosity of 6.7 fb$^{-1}$ recorded by the CDF II detector at the Fermilab Tevatron. The lifetime of the $B_c^{-}$ meson is measured to be $\\tau$($B_c^{-}$) = 0.452 $\\pm$ 0.048(stat) $\\pm$ 0.027(syst) ps. This is the first measurement of the $B_c^{-}$ meson lifetime in a fully-reconstructed hadronic channel, and it agrees with previous results and has comparable precision.

CDF Collaboration

2013-01-03

191

Precision lifetime measurements of N ii levels with the beam-foil-laser method  

NASA Astrophysics Data System (ADS)

Precision lifetime measurements using laser excitation of a fast ion beam preexcited in a carbon foil are reported for two levels in N ii. The cascade-free decays of the fluorescence intensities give lifetimes of 0.249+/-0.004 and 0.267+/-0.010 ns for the N ii 2p3d 1F° and 2p3s 1P° levels, respectively. The lifetime result for the 2p3d 1F° level-which is weakly repopulated by long-lived cascades-is in good agreement with beam-foil values and with the theoretical lifetime of McEachran and Cohen [J. Quant. Spectrosc. Radiat. Transfer 27, 119 (1982)]. The lifetime result for the 2p3s 1P ° level-which is strongly repopulated by cascades-differs significantly from most of the previous experimental values but is in good agreement with the theoretical lifetimes of Luken and Sinanoglu [J. Chem. Phys. 64, 3141 (1976)], Beck and Nicolaides [Phys. Lett. 56A, 265 (1976)], McEachran and Cohen, and Fawcett [At. Data Nucl. Data Tables 37, 411 (1987)]. The f-value trend for the 2p2 1D-2p3s 1P° transition along the C i sequence is discussed.

Baudinet-Robinet, Y.; Garnir, H.-P.; Dumont, P.-D.; Résimont, J.

1990-08-01

192

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

193

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

NASA Astrophysics Data System (ADS)

Defect characterization of as-grown Zn1-xBexSe compound semiconductors was studied by positron lifetime and photoluminescence measurements. We obtain both experimental and theoretical evidence that the bulk lifetime of free positrons decreases linearly with Be alloying. The average positron lifetime increases with the temperature, indicating that both vacancies and negative ions trap positrons. The decomposition of the lifetime spectra shows that the positron lifetime of the vacancy decreases with an increase in Be content, as predicted by theoretical calculations. The concentration of vacancies and negative ions obtained from positron measurements follows the same trend with Be alloying. A comparison of positron measurements with theoretical calculations and photoluminescence experiments in Zn vapor annealed samples indicates that the vacancy corresponds to a Be vacancy. Besides, the negative ions trapping positrons at low temperatures have been attributed to Be interstitial atoms. The intensity of the B photoluminescence band correlates with the concentration of Be vacancies and Be interstitial atoms. We thus conclude that the electron levels of those defects are involved in the optical transition that leads to the B photoluminescence band.

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

2003-08-01

194

Measurement of Structure in the Cosmic-Ray Positron Fraction at GeV Energies  

Microsoft Academic Search

We present the results of a new measurement of the cosmic-ray positron fraction above 4 GeV obtained with the balloon-borne HEAT-pbar instrument. The data from a flight in the spring of 2000 from Ft. Sumner, NM, independently confirm the results of earlier measurements with the HEAT-e^ą instrument. In particular, we notice again some structure near 10 GeV that may suggest

Michael Duvernois; Steve Beach; James Beatty; Amit Bhattacharyya; Charles Bower; Stephane Coutu; Allan Labrador; Shawn McKee; Steve Minnick; Dietrich Müller; James Musser; Scott Nutter; Michael Schubnell; Simon Swordy; Gregory Tarlé; Andrew Tomasch

2002-01-01

195

A new plunger device to measure lifetimes of unbound states in tagged exotic nuclei  

NASA Astrophysics Data System (ADS)

A new plunger device has been designed and is being built at the University of Manchester to measure lifetimes of unbound states in exotic nuclei approaching the proton drip-line. The device is designed to work in both vacuum and gas environments and will be used in conjunction with the gas filled separator RITU and the vacuum-mode separator MARA at the University of Jyväskylä, Finland. This will enable the accurate measurement of excited state lifetimes identified via isomer and charged-particle tagging. The plunger will be used to address many key facets of nuclear structure physics with particular emphasis on the effect of deformation on proton emission rates.

Taylor, M. J.; Cullen, D. M.; Procter, M. G.; Smith, A. J.; Twist, V.; Jones, P. M.; Nieminen, P.; Grahn, T.; Butler, P. A.; Scheck, M.

2012-09-01

196

Variations in the electrical short-circuit current decay for recombination lifetime and velocity measurements  

NASA Technical Reports Server (NTRS)

An improved measurement system for electrical short-circuit current decay is presented that extends applicability of the method to silicon solar cells having an effective lifetime as low as 1 microsec. The system uses metal/oxide/semiconductor transistors as voltage-controlled switches. Advances in theory developed here increase precision and sensitivity in the determination of the minority-carrier recombination lifetime and recombination velocity. A variation of the method, which exploits measurements made on related back-surface field and back-ohmic contact devices, further improves precision and sensitivity. The improvements are illustrated by application to 15 different silicon solar cells.

Jung, Tae-Won; Lindholm, Fredrik A.; Neugroschel, Arnost

1987-01-01

197

Measurement of the ?0b Lifetime Using ?0b-->?+cl-?Ż  

NASA Astrophysics Data System (ADS)

The lifetime of ?0b is measured using the semileptonic decay ?0b-->?+cl-?Ż, where the ?+c is reconstructed through its decay ?+c-->pK-?+. 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 ppŻ collisions at s = 1.8 TeV. From a fit to the decay length distribution of the ?c-lepton system from 197+/-25 signal events, the lifetime of ?0b is measured to be 1.32+/-0.15+/-0.07 ps.

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

1996-08-01

198

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

PubMed

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

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

2005-05-13

199

Nuclear matrix elements from direct lifetime or cross-section measurements  

SciTech Connect

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

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

2012-11-20

200

Excitation and Charge Exchange Phenomena in Astronomical Objects: Measurement of Cross Sections and Lifetimes  

NASA Technical Reports Server (NTRS)

This document addresses extreme ultraviolet radiation and X-ray emissions from comets, planets and heliospheric gases focusing on the measurement of charge-exchange cross sections and radiative lifetimes. Highly-charged heavy ions present in the solar wind, and their abundance relative to the total oxygen-ion abundance are detailed. The plan for the Jet Propulsion Laboratory high-charge ion facility is outlined detailing its ability to measure absolute collisional excitation cross sections, absolute charge-exchange cross sections, lifetimes of metastable ion levels, and X-ray emission spectra following charge changes.

Chutjian, Ara; Smith, S.; Lozano, J.; Cadez, I.; Greewnood, J.; Mawhovter, R.; Williams, I.; Niimura, M.

2003-01-01

201

A new differential plunger to measure lifetimes of unbound states in tagged exotic nuclei  

SciTech Connect

A new differential plunger is being designed and built at the University of Manchester to measure lifetimes of unbound states in exotic nuclei approaching the proton drip-line. The device is designed to work in both vacuum and gas environments and will primarily be used in conjunction with the gas filled separator RITU at the University of Jyvaeskylae, Finland. This will enable the accurate measurement of excited state lifetimes identified via isomer and charged-particle tagging. The plunger will be used to address many key facets of nuclear structure physics with particular emphasis on the effect of deformation on proton emission rates.

Taylor, M. J.; Cullen, D. M.; Smith, A. J.; Twist, V. [School of Physics and Astromony, University of Manchester, Manchester M13 9PL (United Kingdom); Jones, P. M.; Nieminen, P.; Grahn, T. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland); Butler, P. A.; Scheck, M. [Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom)

2011-11-30

202

Measurement of the B- and BŻ0 meson lifetimes using semileptonic decays  

NASA Astrophysics Data System (ADS)

The lifetimes of the B- and BŻ0 mesons are measured using the partially reconstructed semileptonic decays BŻ-->Dl-?ŻX, 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 pŻp collisions at s=1.8 TeV. We measure decay lengths and extract the lifetimes to be ?(B-)=1.637+/-0.058+0.045-0.043 ps and ?(BŻ0)=1.474+/-0.039+0.052-0.051 ps, and the ratio of the lifetimes to be ?(B-)/?(BŻ0)=1.110+/-0.056+0.033-0.030, where the first uncertainties are statistical and the second are systematic.

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

1998-11-01

203

Measurement of the B- and BŻ 0 Meson Lifetimes Using Semileptonic Decays  

NASA Astrophysics Data System (ADS)

The lifetimes of the B- and BŻ 0 mesons are measured using the partially reconstructed semileptonic decays BŻ-->Dl-?ŻX, where D is either a D0 or D*+ meson. The data were collected by the CDF detector at the Fermilab Tevatron collider during 1992-1993 and correspond to 19.3 pb-1 of pŻp collisions at s = 1.8 TeV. We measure the decay length distributions and find the lifetimes to be ?\\(B-\\) = 1.56+/-0.13+/-0.06 ps and ?\\(BŻ 0\\) = 1.54+/-0.08+/-0.06 ps, and the ratio of lifetimes to be ?\\(B-\\)/?\\(BŻ 0\\) = 1.01+/-0.11+/-0.02, where the first uncertainties are statistical and the second are systematic.

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

1996-06-01

204

Phase Space Evolution in Neutron Traps for Measurements of the Neutron Beta-Decay Lifetime  

NASA Astrophysics Data System (ADS)

In trap-based lifetime experiments, the key to extrapolating the neutron ?-decay rate is the understanding of non-?-decay losses of the ultracold neutron (UCN) population in the trap. Use of a magnetic trap eliminates the potential for UCN to be lost at surface boundaries. However, these traps also introduce additional systematic errors, such as spin-flip loss when neutrons cross regions of zero field. In addition, the NIST lifetime experiment reported the unexpected presence of quasi-bound, high-energy neutrons that significantly reduced the measured storage lifetime. We discuss the precision required in measuring these sources of non-?-decay losses and strategies to mitigate some of these effects. The discussion will focus on the magneto-gravitational trap used in the UCN? experiment.

Liu, C.-Y.; Salvat, D.; Adamek, E.

2014-03-01

205

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

206

Near Infrared Dyes as Lifetime Solvatochromic Probes for Micropolarity Measurements of Biological Systems  

E-print Network

Near Infrared Dyes as Lifetime Solvatochromic Probes for Micropolarity Measurements of Biological, metabolism, and excretion. With the recent widespread use of near-infrared (NIR) fluorescent dyes, ultraviolet/visible/near-infrared (NIR) absorption, and fluorescence (7,8) have been developed. The latter

Larson-Prior, Linda

207

Lifetime measurements in the regular [Delta][ital I]=1 oblate band in [sup 197]Pb  

Microsoft Academic Search

Lifetimes of states in the regular [Delta][ital I]=1 band in [sup 197]Pb have been measured with the Doppler-shift attenuation method. Excited states in [sup 197]Pb were populated using the [sup 154]Sm([sup 48]Ca, 5[ital n]) reaction at [ital E][sub [ital b

J. R. Hughes; J. A. Becker; M. J. Brinkman; E. A. Henry; R. W. Hoff; M. A. Stoyer; T. F. Wang; B. Cederwall; M. A. Deleplanque; R. M. Diamond; P. Fallon; I. Y. Lee; J. R. B. Oliveira; F. S. Stephens; J. A. Cizewski; L. A. Bernstein; J. E. Draper; C. Duyar; E. Rubel; W. H. Kelly; D. Vo

1993-01-01

208

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

E-print Network

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

Aaij, R.

209

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

210

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

211

Setup and operation of gamma-ray measurement systems to maximize detector lifetime and stability  

Microsoft Academic Search

The details for optimizing gamma-ray measurement system for specific applications are not always well understood. The setup and operation of a system plays an important role in performance aspects such as maximizing detector lifetime, stability and minimizing the signal to noise ratio. In addition to system setup and operation, the effects of scintillation detector design and accompanying electronics (PMT) are

David G. Penn; Carlos M. Grodsinsky

1999-01-01

212

CDF note xxxx Measurement of the B s # K + K -lifetime and extraction of ## CP /# CP  

E-print Network

fit two already well consolidated CDF analysis techniques. The first uses kinematics and PID to about 360 pb -1 . The CDF Run II has a three levels trigger. The hadronic trigger used in this analysisCDF note xxxx Measurement of the B s # K + K - lifetime and extraction of ## CP /# CP The CDF

Fermilab

213

Lifetime Measurements of theA4?,B4?, andC4?-States of VO  

NASA Astrophysics Data System (ADS)

Lifetime measurements of theA4?,B4?, andC4?-electronic states of the vanadium monoxide molecule were performed using population probing of resonant two-photon ionization in a molecular beam. These lifetimes were found to be 6 ą 1 ?sec, 0.37 ą 0.05 ?sec, and 73 ą 2 nsec, respectively, for thev= 0 levels. Due to the very low rotational temperature, the first lines were observed for theA4?-X4?-transition and some consequences are discussed.

Karlsson, Lars; Lindgren, Bo; Lundevall, Cecilia; Sassenberg, Ulf

1997-02-01

214

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

215

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

216

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

PubMed Central

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

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

1982-01-01

217

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

218

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

PubMed

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

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

2014-09-19

219

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

E-print Network

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

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

2014-01-01

220

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

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

221

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

SciTech Connect

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

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

2013-04-19

222

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

223

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

224

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

225

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

226

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

227

Gain saturation study and measurement of terminal level lifetime for Yb:YAG crystal  

NASA Astrophysics Data System (ADS)

We formulate a set of coupled rate equations describing the dynamic behaviour of a laser extraction based on the energy-level structure of a Yb:YAG crystal. A numerical computation of the energy extraction is carried out which includes the effects of the pulse width and the terminal level lifetime. According to the result of the computation, we formulated an empirical expression for the saturation fluence in Yb:YAG crystals that explicitly depends upon the ratio of the pulse width to the terminal level lifetime. The empirical saturation fluence, when substituted within the Frantz and Nodvik solution for energy extraction, can be used to accurately model the energy extracted from Yb:YAG crystal amplifiers. An experiment is performed in a Yb:YAG disc amplifier to measure the input fluence, output fluence and pulse length. We compare the experimental gain saturation data of the Yb:YAG disc amplifier with our empirical solution and determine the terminal level lifetime from a best fit to the data. The terminal level lifetime of Yb:YAG is found to be 275?ps ą 105?ps.

Yan, Xiongwei; Zheng, Jiangang; Jiang, Xingyin; Li, Mingzhong; Li, Min; Wang, Zhengguo

2014-12-01

228

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

NASA Astrophysics Data System (ADS)

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.; Coakley, K.; Gilliam, D.; Greene, G.; Laptev, A.; Nico, J.; Snow, W.; Wietfeldt, F.; Yue, A.

2009-12-01

229

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

230

A Direct Measurement of Lifetimes and Stellar Luminosities on the AGB  

NASA Astrophysics Data System (ADS)

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

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

2015-01-01

231

A measurement of B$^{+}$ and B$^{0}$ lifetimes using $\\\\overline{D}$l$^{+}$ events  

Microsoft Academic Search

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

P Abreu; W Adam; T Adye; E Agasi; I Ajinenko; Roy Aleksan; G D Alekseev; P P Allport; S Almehed; S J Alvsvaag; Ugo Amaldi; S Amato; A Andreazza; M L Andrieux; P Antilogus; W D Apel; Y Arnoud; B Ĺsman; J E Augustin; A Augustinus; Paul Baillon; P Bambade; F Barăo; R Barate; Guido Barbiellini; Dimitri Yuri Bardin; G J Barker; A Baroncelli; O Bärring; J A Barrio; Walter Bartl; M J Bates; Marco Battaglia; M Baubillier; J Baudot; K H Becks; M Begalli; P Beilličre; Yu A Belokopytov; Alberto C Benvenuti; M Berggren; D Bertrand; F Bianchi; M Bigi; S M Bilenky; P Billoir; D Bloch; M Blume; S Blyth; V Bocci; T Bolognese; M Bonesini; W Bonivento; P S L Booth; G Borisov; C Bosio; S Bosworth; O Botner; B Bouquet; C Bourdarios; T J V Bowcock; M Bozzo; P Branchini; K D Brand; R A Brenner; C Bricman; L Brillault; R C A Brown; P Brückman; J M Brunet; L Bugge; T Buran; A Buys; M Caccia; M Calvi; A J Camacho-Rozas; T Camporesi; V Canale; M Canepa; K Cankocak; F Cao; F Carena; P Carrilho; L Carroll; Carlo Caso; M V Castillo-Gimenez; A Cattai; F R Cavallo; L Cerrito; V Chabaud; M M Chapkin; P Charpentier; L Chaussard; J Chauveau; P Checchia; G A Chelkov; R Chierici; P V Chliapnikov; P Chochula; V Chorowicz; V Cindro; P Collins; J L Contreras; R Contri; E Cortina; G Cosme; F Cossutti; H B Crawley; D J Crennell; G Crosetti; J Cuevas-Maestro; S Czellar; Erik Dahl-Jensen; J Dahm; B D'Almagne; M Dam; G Damgaard; A Daum; P D Dauncey; Martyn Davenport; W Da Silva; C Defoix; G Della Ricca; P A Delpierre; N Demaria; A De Angelis; H De Boeck; Wim de Boer; S De Brabandere; C De Clercq; C de La Vaissičre; B De Lotto; A De Min; L S De Paula; C De Saint-Jean; H Dijkstra; Lucia Di Ciaccio; F Djama; J Dolbeau; M Dönszelmann; K Doroba; M Dracos; J Drees; K A Drees; M Dris; Y Dufour; F Dupont; D M Edsall; R Ehret; G Eigen; T J C Ekelöf; Gösta Ekspong; M Elsing; J P Engel; N Ershaidat; B Erzen; E Falk; D Fassouliotis; Michael Feindt; A Fenyuk; A Ferrer; A Filippas-Tassos; A Firestone; P A Fischer; H Föth; E Fokitis; F Fontanelli; F Formenti; B J Franek; P Frenkiel; D E C Fries; A G Frodesen; R Frühwirth; F Fulda-Quenzer; H Fürstenau; J A Fuster; A Galloni; D Gamba; M Gandelman; C García; J García; C Gaspar; U Gasparini; P Gavillet; E N Gazis; D Gelé; J P Gerber; M Gibbs; D Gillespie; R Gokieli; B Golob; Gian P Gopal; L Gorn; M Górski; Yu Guz; Valerio Gracco; E Graziani; G Grosdidier; P Gunnarsson; M Günther; J Guy; U Haedinger; F Hahn; M Hahn; S Hahn; Z Hajduk; A Hallgren; K Hamacher; W Hao; F J Harris; V Hedberg; R P Henriques; J J Hernández; P Herquet; H Herr; T L Hessing; E Higón; Hans Jürgen Hilke; T S Hill; S O Holmgren; P J Holt; D J Holthuizen; M A Houlden; Josef Hrubec; K Huet; K Hultqvist; P Ioannou; J N Jackson; R Jacobsson; P Jalocha; R Janik; G Jarlskog; P Jarry; B Jean-Marie; E K Johansson; L B Jönsson; P E Jönsson; Christian Joram; P Juillot; M Kaiser; George Ernest Kalmus; F Kapusta; M Karlsson; E Karvelas; S Katsanevas; E C Katsoufis; R Keränen; B A Khomenko; N N Khovanskii; B J King; N J Kjaer; H Klein; A Klovning; P M Kluit; J H Köhne; B Köne; P Kokkinias; M Koratzinos; V Kostyukhin; C Kourkoumelis; O Kuznetsov; P H Kramer; Manfred Krammer; C Kreuter; J Królikowski; I J Kronkvist; Z Krumshtein; W Krupinski; P Kubinec; W Kucewicz; K L Kurvinen; C Lacasta; I Laktineh; S Lamblot; J Lamsa; L Lanceri; P Langefeld; I Last; J P Laugier; R Lauhakangas; Gerhard Leder; F Ledroit; V Lefébure; C K Legan; R Leitner; Y Lemoigne; J Lemonne; Georg Lenzen; V Lepeltier; T Lesiak; D Liko; R Lindner; A Lipniacka; I Lippi; B Lörstad; M Lokajícek; J G Loken; J M López; A López-Fernandez; M A López-Aguera; D Loukas; P Lutz; L Lyons; J N MacNaughton; G Maehlum; A Maio; V Malychev; F Mandl; J Marco; B Maréchal; M Margoni; J C Marin; C Mariotti; A Markou; T Maron; C Martínez-Rivero; F Martínez-Vidal; S Martí i García; F Matorras; C Matteuzzi; Giorgio Matthiae; M Mazzucato; M L McCubbin; M McKay; M McNulty; J Medbo; C Meroni; W T Meyer; M Michelotto; E Migliore; L Mirabito; Winfried A Mitaroff; U Mjörnmark; T Moa; R Mřller; K Mönig; M R Monge; P Morettini; H Müller; L M Mundim; W J Murray; B Muryn; Gerald Myatt; F Naraghi; Francesco Luigi Navarria; S Navas; P Negri; S Némécek; W Neumann; R Nicolaidou; B S Nielsen; M Nieuwenhuizen; V Nikolaenko; P Niss; A Nomerotski; Ainsley Normand; W Oberschulte-Beckmann; V F Obraztsov; A G Olshevskii; A Onofre; Risto Orava; K Österberg; A Ouraou; P Paganini; M Paganoni; P Pagčs; H Palka; T D Papadopoulou; L Pape; C Parkes; F Parodi; A Passeri; M Pegoraro; L Peralta; H Pernegger; Manfred Pernicka; A Perrotta; C Petridou; A Petrolini; H T Phillips; G Piana; F Pierre; M Pimenta; S Plaszczynski; O Podobrin; M E Pol; G Polok; P Poropat; V Pozdnyakov; M Prest; P Privitera; N Pukhaeva; Antonio Pullia; D Radojicic; S Ragazzi; H Rahmani; J Rames; P N Ratoff; A L Read; M Reale

1995-01-01

232

Contactless measurement of bulk free-carrier lifetime in cast polycrystalline silicon ingots  

Microsoft Academic Search

The spatial dependence of the bulk free-carrier lifetime in cast polycrystalline silicon ingots was determined from contactless measurements of optically modulated free-carrier infrared absorption. Using a cw Nd: yttrium aluminum garnet (Nd:YAG) laser (?=1.319 ?m) for a probe and a novel pulsed tunable infrared dye laser (?=1.10–1.13 ?m), with photon energies near the Si band gap, for a pump, the

S. M. Johnson; L. G. Johnson

1986-01-01

233

Contactless measurement of bulk free-carrier lifetime in cast polycrystalline silicon ingots  

Microsoft Academic Search

The spatial dependence of the bulk free-carrier lifetime in cast polycrystalline silicon ingots was determined from contactless measurements of optically modulated free-carrier infrared absorption. Using a cw Nd: yttrium aluminum garnet (Nd:YAG) laser (lambda = 1.319 ..mu..m) for a probe and a novel pulsed tunable infrared dye laser (lambda = 1.10--1.13 ..mu..m), with photon energies near the Si band gap,

S. M. Johnson; L. G. Johnson

1986-01-01

234

Study of excitation transfer in laser dye mixtures by direct measurement of fluorescence lifetime  

NASA Technical Reports Server (NTRS)

By directly measuring the donor fluorescence lifetime as a function of acceptor concentration in the laser dye mixture Rhodamine 6G-Cresyl violet, we found that the Stern-Volmer relation is obeyed, from which the rate of excitation transfer is determined. The experimental results indicate that the dominant mechanism responsible for the efficient excitation transfer is that of resonance transfer due to long range dipole-dipole interaction.

Lin, C.; Dienes, A.

1973-01-01

235

Measurements of mean lifetime and branching fractions of b hadrons decaying to J\\/psi  

Microsoft Academic Search

From a data sample of 450 000 hadronic events recorded with the ALEPH detector at LEP, 92+\\/-10 events are observed containing a J\\/psi meson decaying to mu+mu- or e+e-. From these data the measured inclusive branching fraction for a b flavoured hadron to decay to a J\\/psi is BR(b--> J\\/psiX) = (1.21+\\/-0.13 (stat.)+\\/-0.08 (syst.))%, and the average b hadron lifetime

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

1992-01-01

236

A measurement of charmed hadron lifetimes at radical s = 10. 5 GeV  

SciTech Connect

The results of the lifetime measurements of the charmed D{sup 0}, D{sup +}, D{sub S}, and {Lambda}{sub c}{sup +} hadrons are reported. The measurements are made u sing the CLEO detector at the Cornell Electron Storage Ring at a center of mass energy of 10.5 GeV. In total 8,120 D{sup 0}, 5,477 D{sup +}, 523 D{sub S}{sup +}, and 604 {Lambda}{sub c}{sup +} candidates are reconstructed in nine independent decay modes. The lifetime measurements is the use of decay modes in which one of the decay products is a K{sub S}{sup 0}. Combining the results from all decays modes, the following charm lifetimes are reported: {tau}{sub D{sup 0}} = 4.64 {plus minus} 0.17 {plus minus} 0.07 {times} 10{sup {minus}13} sec, {tau}{sub D{sup +}} = 11.5 {plus minus} 0.40 {plus minus} 0.30 {times} 10{sup {minus}13} sec, {tau}{sub D{sub s}} = 4.33 {plus minus} 0.87 {plus minus} 0.35 {times} 10{sup {minus}13} sec, and {tau}{sub {Lambda}{sub c}} = 3.20 {plus minus} 1.29 {plus minus} 0.62 {times} 10{sup {minus}13} sec.

Johnson, D.R.

1990-01-01

237

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

SciTech Connect

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

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

2010-04-01

238

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

239

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

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

240

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

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

241

Measurement of the metastable lifetime for the 2s^2 2p^2 ^1So level in O^2+  

NASA Technical Reports Server (NTRS)

The radiative lifetime of the 1S0 level was found to be 540 +/- 27 ms. This is in good agreement with a previous measurement and with a number of theoretical calculations. Metastable lifetimes, when combined with collisional excitation rates, can provide a diagnostic for electron density Ne in a stellar or solar plasma.

Smith, S. J.; Cadez, I.; Chutjian, A.; Niimura, M.

2004-01-01

242

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

243

Calibration of an advanced photon source linac beam position monitor used for positron position measurement of a beam containing both positrons and electrons  

SciTech Connect

The Advanced Photon Source (APS) linac beam position monitors can be used to monitor the position of a beam containing both positrons and electrons. To accomplish this task, both the signal at the bunching frequency of 2856 MHz and the signal at 2x2856 MHz are acquired and processed for each stripline. The positron beam position is obtained by forming a linear combination of both 2856 and 5712 MHz signals for each stripline and then performing the standard difference over sum computation. The required linear combination of the 2856 and 5712 MHz signals depends on the electrical calibration of each stripline/cable combination. In this paper, the calibration constants for both 2856 MHz and 5712 MHz signals for each stripline are determined using a pure beam of electrons. The calibration constants are obtained by measuring the 2856 and 5712 MHz stripline signals at various electron beam currents and positions. Finally, the calibration constants measured using electrons are used to determine positron beam position for the mixed beam case.

Sereno, Nicholas S. [Advanced Photon Source, Argonne National Laboratory 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)

1998-12-10

244

Calibration of an advanced photon source linac beam position monitor used for positron position measurement of a beam containing both positrons and electrons  

SciTech Connect

The Advanced Photon Source (APS) linac beam position monitors can be used to monitor the position of a beam containing both positrons and electrons. To accomplish this task, both the signal at the bunching frequency of 2856 MHz and the signal at 2{times}2856MHz are acquired and processed for each stripline. The positron beam position is obtained by forming a linear combination of both 2856 and 5712 MHz signals for each stripline and then performing the standard difference over sum computation. The required linear combination of the 2856 and 5712 MHz signals depends on the electrical calibration of each stripline/cable combination. In this paper, the calibration constants for both 2856 MHz and 5712 MHz signals for each stripline are determined using a pure beam of electrons. The calibration constants are obtained by measuring the 2856 and 5712 MHz stripline signals at various electron beam currents and positions. Finally, the calibration constants measured using electrons are used to determine positron beam position for the mixed beam case. {copyright} {ital 1998 American Institute of Physics.}

Sereno, N.S. [Advanced Photon Source, Argonne National Laboratory 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)

1998-12-01

245

Calibration of an Advanced Photon Source linac beam position monitor used for positron position measurement of a beam containing both positrons and electrons.  

SciTech Connect

The Advanced Photon Source (APS) linac beam position monitors can be used to monitor the position of a positron beam also containing electrons. To accomplish this task, both the signal at the bunching frequency of 2856 MHz and the signal at 2 x 2856 MHz are acquired and processed for each stripline. The positron beam position is obtained by forming a linear combination of both 2856- and 5712-MHz signals for each stripline and then performing the standard difference over sum computation. The required linear combination of the 2856- and 5712-MHz signals depends on the electrical calibration of each stripline/cable combination. In this paper, the calibration constants for both 2856-MHz and 5712-MHz signals for each stripline are determined using a pure beam of electrons. The calibration constants are obtained by measuring the 2856- and 5712-MHz stripline signals at various electron beam currents and positions. Finally, the calibration constants measured using electrons are used to determine positron beam position for the mixed beam case.

Sereno, N. S.

1998-05-19

246

Measurement of human cerebral blood flow with (15O)butanol and positron emission tomography  

SciTech Connect

Although H2(15)O is widely used for CBF measurement by positron tomography, it underestimates CBF, especially at elevated flow rates. Several tracers, including butanol, overcome this problem, but the short half-life of 15O provides advantages that cause water to remain the tracer of choice. The authors report the first use and evaluation of 15O-labeled butanol for CBF measurement. Flow measurements made in a similar fashion with water and butanol at 10-min intervals were compared in normal volunteers under resting and hypercapnic conditions. Regional analysis showed good agreement between the tracers at low flows, and significant underestimation of flow by water relative to butanol in regions of elevated flow. The observed relationship between the tracers and the curve-fitted permeability-surface area product for water (133 ml.100 g-1.min-1) follow the known relationship between water and true flow. These observations indicate that (15O)-butanol provided accurate measurements of human regional CBF under conditions of elevated perfusion. They conclude that butanol is a convenient and accurate method for routine CBF determination by positron emission tomography.

Berridge, M.S.; Adler, L.P.; Nelson, A.D.; Cassidy, E.H.; Muzic, R.F.; Bednarczyk, E.M.; Miraldi, F. (Case Western Reserve University, School of Medicine, Cleveland, OH (USA))

1991-09-01

247

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 feasibility of this idea, by implementing DC bump in NSLS X-ray ring. We report the results of beam lifetime measurements as a function of the amplitude of this bumped orbit relative to the septum and the idea of a slow bump that could reduce the fast bump magnet strengths.

Wang, G.M.; Choi; J.; Kramer; S.; Shaftan; T.; Heese; R.; Yang; X.

2011-03-28

248

Apparatus and method 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 linearity 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); Johnston, Steven W. (Golden, CO)

2001-01-01

249

Investigation into the Effects of Deformation on Proton Emission Rates via Lifetime Measurements  

NASA Astrophysics Data System (ADS)

Excited states in the proton-unbound nucleus 151Lu have been established using ?-ray coincidence techniques. The lifetime of the first excited state above the proton-emitting ground state has been measured using the recoil-distance Doppler-shift method combined with recoil-decay tagging. The experimental level scheme and extracted lifetime have been compared with state-of-the-art theoretical calculations based upon a non-adiabatic deformed Woods-Saxon potential. This comparison suggests that the proton-emitting ground state in 151Lu is mildly oblate with a deformation {? _2} = - 0.11_{ - 0.05}^{ + 0.02} and represents the best evidence to date for proton emission from an oblate nucleus.

Taylor, M. J.; Cullen, D. M.; Procter, M. G.; Smith, A. J.; McFarlane, A.; Twist, V.; Alharshan, G. A.; Grahn, T.; Greenlees, P. T.; Auranen, K.; Hauschild, K.; Herzan, A.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Konki, J.; Leino, M.; Lopez-Martens, A.; Nieminen, P.; Pakarinen, J.; Partanen, J.; Peura, P.; Rahkila, P.; Rinta-Antila, S.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J.; Ferreira, L. S.; Maglione, E.; Butler, P. A.; Scheck, M.; Joss, D. T.; Sahgi, B.; McPeake, C.; Braunroth, T.; Dewald, A.; Fransen, C.; Ellinger, E.

2015-11-01

250

Positron Annihilation Spectroscopy Of High Performance Polymer Films Under CO2 Pressure  

NASA Astrophysics Data System (ADS)

Positron annihilation Lifetime and Doppler broadening measurements are reported for six polymer films as a function of carbon dioxide (CO2) absolute pressure ranging from 0 to 45 psi. Since the polymer films were thin and did not absorb all positrons, corrections were made in the lifetime analysis for the absorption of positrons in the positron source and sample holder using the Monte Carlo transport code MCNP. The studied polymers are found to behave differently from each other. Some polymers form positronium and others, such as the polyimide structures, do not. For those polymers that form positronium an interpretation in terms of free volume is possible; for those that don't form positronium, further work is needed to determine how best to describe the behavior in terms of the bulk positron annihilation parameters. A few of the studied polymers exhibit changes in positron lifetime and intensity under CO2 pressure which may be described by the Henry or Langmuir sorption models, while the positron response of other polymers is rather insensitive to the CO2 pressure. The results demonstrate the usefulness of positron annihilation spectroscopy in investigating the sorption of CO2 into various polymers at pressures up to about 3 atm (45psi).

Quarles, C. A.; Klaehn, John R.; Peterson, Eric S.; Urban-Klaehn, Jagoda M.

2011-06-01

251

Positron emission tomography for measurement of copper fluxes in live organisms.  

PubMed

Copper is an essential nutrient for the physiology of live organisms, but excessive copper can be harmful. Copper radioisotopes are used for measurement of copper fluxes in live organisms using a radioactivity assay of body fluids or whole-body positron emission tomography (PET). Hybrid positron emission tomography-computed tomography (PET/CT) is a versatile tool for real-time measurement of copper fluxes combining the high sensitivity and quantification capability of PET and the superior spatial resolution of CT for anatomic localization of radioactive tracer activity. Kinetic analysis of copper metabolism in the liver and extrahepatic tissues of Atp7b(-/-) knockout mice, a mouse model of Wilson's disease, demonstrated the feasibility of measuring copper fluxes in live organisms with PET/CT using copper-64 chloride ((64) CuCl2 ) as a radioactive tracer ((64) CuCl2 -PET/CT). (64) CuCl2 -PET/CT holds potential as a useful tool for the diagnosis of inherited and acquired human copper metabolism disorders and for monitoring the effects of copper-modulating therapy. PMID:24628290

Peng, Fangyu

2014-05-01

252

Electroweak Measurements in Electron-Positron Collisions at W-Boson-Pair Energies at LEP  

E-print Network

Electroweak measurements performed with data taken at the electron-positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3~fb$^{-1}$ collected by the four LEP experiments ALEPH, DELPHI, L3 and OPAL, at centre-of-mass energies ranging from $130~GeV$ to $209~GeV$. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron-positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose-Einstein correlations between the two W decay systems arising ...

Schael, S; Bruneliere, R; Buskulic, D; De Bonis, I; Decamp, D; Ghez, P; Goy, C; Jezequel, S; Lees, J P; Lucotte, A; Martin, F; Merle, E; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Trocme, B; Bravo, S; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Fernandez, E; Fernandez-Bosman, M; Garrido, Ll; Grauges, E; Juste, A; Martinez, M; Merino, G; Miquel, R; Mir, Ll. M; Orteu, S; Pacheco, A; Park, I C; Perlas, J; Riu, I; Ruiz, H; Sanchez, F; Colaleo, A; Creanza, D; De Filippis, N; 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; Bazarko, A; Becker, U; Boix, G; Bird, F; Blucher, E; Bonvicini, B; Bright-Thomas, P; Barklow, T; Buchmuller, O; Cattaneo, M; Cerutti, F; Ciulli, V; Clerbaux, B; Drevermann, H; Forty, R W; Frank, M; Greening, T C; Hagelberg, R; Halley, A W; Gianotti, F; Girone, M; Hansen, J B; Harvey, J; Jacobsen, R; Hutchcroft, D E; Janot, P; Jost, B; Knobloch, J; Kado, M; Lehraus, I; Lazeyras, P; Maley, P; Mato, P; May, J; Moutoussi, A; Pepe-Altarelli, M; Ranjard, F; Rolandi, L; Schlatter, D; Schmitt, B; Schneider, O; Tejessy, W; Teubert, F; Tomalin, I R; Tournefier, E; Veenhof, R; Valassi, A; Wiedenmann, W; Wright, A E; Ajaltouni, Z; Badaud, F; Chazelle, G; Deschamps, O; Dessagne, S; Falvard, A; Ferdi, C; Fayolle, D; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Pascolo, J M; Perret, P; Podlyski, F; Bertelsen, H; Fernley, T; Hansen, J D; Hansen, J R; Hansen, P H; Kraan, A C; Lindahl, A; Mollerud, R; Nilsson, B S; Rensch, B; Waananen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, E; Siotis, I; Vayaki, A; Zachariadou, K; Blondel, A; Bonneaud, G; Brient, J C; Machefert, F; Rouge, A; Rumpf, M; Swynghedauw, M; Tanaka, R; Verderi, M; Videau, H; Ciulli, V; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C; Antonelli, A; Antonelli, M; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Cerutti, F; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, G P; Passalacqua, L; Picchi, P; Colrain, P; Have, I. ten; Hughes, I S; Kennedy, J; Knowles, I G; Lynch, J G; Morton, W T; Negus, P; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Thompson, A S; Turnbull, R M; Wasserbaech, S; Buchmuller, O; Cavanaugh, R; Dhamotharan, S; Geweniger, C; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Sommer, J; Stenzel, H; Tittel, K; Werner, W; Wunsch, M; Beuselinck, R; Binnie, D M; Cameron, W; Davies, G; Dornan, P J; Goodsir, S; Marinelli, N; Martin, E B; Nash, J; Nowell, J; Rutherford, S A; Sedgbeer, J K; Thompson, J C; White, R; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bouhova-Thacker, E; Bowdery, C K; Buck, P G; Clarke, D P; Ellis, G; Finch, A J; Foster, F; Hughes, G; Jones, R.W L; Keemer, N R; Pearson, M R; Robertson, N A; Sloan, T; Smizanska, M; Snow, S W; Williams, M I; van der Aa, O; Delaere, C; Leibenguth, G; Lemaitre, V; Bauerdick, L.A T; Blumenschein, U; van Gemmeren, P; Giehl, I; Holldorfer, F; Jakobs, K; Kasemann, M; Kayser, F; Kleinknecht, K; Muller, A S; Quast, G; Renk, B; Rohne, E; Sander, H G; Schmeling, S; Wachsmuth, H; Wanke, R; Zeitnitz, C; Ziegler, T; Aubert, J J; Benchouk, C; Bonissent, A; Carr, J; Coyle, P; Curtil, C; Ealet, A; Etienne, F; Fouchez, D; Motsch, F; Payre, P; Rousseau, D; Tilquin, A; Talby, M; Thulasidas, M; Aleppo, M; Antonelli, M; Ragusa, F; Buscher, V; David, A; Dietl, H; Ganis, G; Huttmann, K; Lutjens, G; Mannert, C; Manner, W; Moser, H G; Settles, R; Seywerd, H; Stenzel, H; Villegas, M; Wiedenmann, W; Wolf, G; Azzurri, P; Boucrot, J; Callot, O; Chen, S; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, Ph; Jacholkowska, A; Le Diberder, F; Lefrancois, J; Mutz, A M; Schune, M H; Serin, L; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Bettarini, S; Boccali, T; Bozzi, C; Calderini, G; Dell'Orso, R; Fantechi, R; Ferrante, I; Fidecaro, F; Foa, L; Giammanco, A; Giassi, A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, F; Rizzo, G; Sanguinetti, G; Sciaba, A; Sguazzoni, G; Spagnolo, P; Steinberger, J; Tenchini, R; Vannini, C; Venturi, A; Verdini, P G; Awunor, O; Blair, G A; Cowan, G; Garcia-Bellido, A; Green, M G; Medcalf, T; Misiejuk, A; Strong, J A; Teixeira-Dias, P; Botterill, D R; Clifft, R W; Edgecock, T R; Edwards, M; Haywood, S J; Norton, P R; Tomalin, I R; Ward, J J; Bloch-Devaux, B; Boumediene, D; Colas, P; Emery, S; Fabbro, B; Kozanecki, W; Lancon, E; Lemaire, M C; Locci, E; Perez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Tuchming, B; Vallage, B; Black, S N; Dann, J H; Kim, H Y; Konstantinidis, N; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Cartwright, S

2013-01-01

253

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

SciTech Connect

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

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

2009-03-10

254

Measurement of the neutron lifetime with ultra-cold neutrons stored in a magneto-gravitational trap  

E-print Network

We report a new measurement of the neutron lifetime using ultra-cold neutrons stored in a magneto-gravitational trap made of permanent magnets. Neutrons surviving in the trap after fixed storage times have been counted and the trap losses have continuously been monitored during storage by detecting neutrons leaking from the trap. The value of the neutron lifetime resulting from this measurement is $\\tau_n=(878.3\\pm1.9)$s. It is the most precise measurement of the neutron lifetime obtained with magnetically stored neutrons.

V. F. Ezhov; A. Z. Andreev; G. Ban; B. A. Bazarov; P. Geltenbort; A. G. Glushkov; V. A. Knyazkov; N. A. Kovrizhnykh; G. B. Krygin; O. Naviliat-Cuncic; V. L. Ryabov

2014-12-23

255

Measurement of the B hadron lifetime from Mark II at PEP  

SciTech Connect

Using data taken by the Mark II detector at PEP, the decays of B hadrons are tagged by identifying leptons at high transverse momentum. By means of a precision inner drift chamber, the impact parameters of these leptons are measured with respect to the B production point. From this impact parameter distribution, the B hadron lifetime is found to be 0.98 +- 0.12 +- 0.13 ps. This measurement can be used to place constraints models of quark mixing. 11 refs., 2 figs., 2 tabs.

Ong, R.A.

1988-01-01

256

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

PubMed

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

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

2005-10-21

257

Measurement of the B[+ over c] meson lifetime using B[+ over c] ? J/? ?[superscript +] ? [subscript ?] X decays  

E-print Network

The lifetime of the B[+ over c] meson is measured using semileptonic decays having a J/? meson and a muon in the final state. The data, corresponding to an integrated luminosity of 2 fb[superscript -1], are collected by ...

Counts, Ian Thomas Hunt

258

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

NASA Astrophysics Data System (ADS)

We present a measurement of the branching fractions for decay from the long-lived 5 D5 /2 level in 138Ba+. The branching fraction for decay into the 6 S1 /2 ground state was found to be 0.846 (25) stat(4) sys . We also report an improved measurement of the 5 D5 /2 lifetime, ?5 D5/2=31.2 (0.9 ) s. Together these measurements provide an experimental determination of transition rates for decay out of the 5 D5 /2 level. The low (<7 ×10-12 Torr) pressure in the ion trap in which these measurements were made simplified data acquisition and analysis. Comparison of the experimental results with theoretical predictions of the transition rates shows good agreement.

Auchter, Carolyn; Noel, Thomas W.; Hoffman, Matthew R.; Williams, Spencer R.; Blinov, Boris B.

2014-12-01

259

Measured lifetimes of metastable levels of Mn X, Mn XI, Mn XII, and Mn XIII ions  

E-print Network

. The measured lifetimes are tau(Mn X, 3s(2)3p(4) S-1(0)) = 2.1 +/- 0.3, tau(Mn X, 3s(2)3p(4) D-1(2)) = 18.02 +/- 0.16, tau(Mn XI, 3s(2)3p(3) P-2(3/2)) = 3.0 +/- 0.2, tau(Mn XI, 3s(2)3p(3) P-2(1/2)) = 6.17 +/- 0.29, tau(Mn XI, 3s(2)3p(3) D-2(3/2)) = 35.1 +/- 1...

Moehs, D. P.; Church, David A.

1999-01-01

260

Measurement of Lifetime and Decay-Width Difference in Bs0-->J\\/psivarphi Decays  

Microsoft Academic Search

We measure the mean lifetime tau=2\\/(GammaL+GammaH) and the decay-width difference DeltaGamma=GammaL-GammaH of the light and heavy mass eigenstates of the Bs0 meson, BsL0 and BsH0, in Bs0-->J\\/psivarphi decays using 1.7fb-1 of data collected with the CDF II detector at the Fermilab Tevatron p pmacr collider. Assuming CP conservation, a good approximation for the Bs0 system in the standard model, we

T. Aaltonen; A. Abulencia; J. Adelman; T. Akimoto; M. G. Albrow; B. Álvarez González; S. Amerio; D. Amidei; A. Anastassov; A. Annovi; J. Antos; G. Apollinari; A. Apresyan; T. Arisawa; A. Artikov; W. Ashmanskas; A. Attal; A. Aurisano; F. Azfar; P. Azzi-Bacchetta; P. Azzurri; N. Bacchetta; W. Badgett; A. Barbaro-Galtieri; V. E. Barnes; B. A. Barnett; S. Baroiant; V. Bartsch; G. Bauer; P.-H. Beauchemin; F. Bedeschi; P. Bednar; S. Behari; G. Bellettini; J. Bellinger; A. Belloni; D. Benjamin; A. Beretvas; J. Beringer; T. Berry; A. Bhatti; M. Binkley; D. Bisello; I. Bizjak; R. E. Blair; C. Blocker; B. Blumenfeld; A. Bocci; A. Bodek; V. Boisvert; G. Bolla; A. Bolshov; D. Bortoletto; J. Boudreau; A. Boveia; B. Brau; L. Brigliadori; C. Bromberg; E. Brubaker; J. Budagov; H. S. Budd; S. Budd; K. Burkett; G. Busetto; P. Bussey; A. Buzatu; K. L. Byrum; S. Cabrera; M. Campanelli; M. Campbell; F. Canelli; A. Canepa; D. Carlsmith; R. Carosi; S. Carrillo; S. Carron; B. Casal; M. Casarsa; A. Castro; P. Catastini; D. Cauz; M. Cavalli-Sforza; A. Cerri; L. Cerrito; S. H. Chang; Y. C. Chen; M. Chertok; G. Chiarelli; G. Chlachidze; F. Chlebana; K. Cho; D. Chokheli; J. P. Chou; G. Choudalakis; S. H. Chuang; K. Chung; W. H. Chung; Y. S. Chung; C. I. Ciobanu; M. A. Ciocci; A. Clark; D. Clark; G. Compostella; M. E. Convery; J. Conway; B. Cooper; K. Copic; M. Cordelli; G. Cortiana; F. Crescioli; C. Cuenca Almenar; J. Cuevas; R. Culbertson; J. C. Cully; D. Dagenhart; M. Datta; T. Davies; P. de Barbaro; S. de Cecco; A. Deisher; G. de Lentdecker; G. de Lorenzo; M. Dell'Orso; L. Demortier; J. Deng; M. Deninno; D. de Pedis; P. F. Derwent; G. P. di Giovanni; C. Dionisi; B. di Ruzza; J. R. Dittmann; M. D'Onofrio; S. Donati; P. Dong; J. Donini; T. Dorigo; S. Dube; J. Efron; R. Erbacher; D. Errede; S. Errede; R. Eusebi; H. C. Fang; S. Farrington; W. T. Fedorko; R. G. Feild; M. Feindt; J. P. Fernandez; C. Ferrazza; R. Field; G. Flanagan; R. Forrest; S. Forrester; M. Franklin; J. C. Freeman; I. Furic; M. Gallinaro; J. Galyardt; F. Garberson; J. E. Garcia; A. F. Garfinkel; H. Gerberich; D. Gerdes; S. Giagu; P. Giannetti; K. Gibson; J. L. Gimmell; C. M. Ginsburg; N. Giokaris; M. Giordani; P. Giromini; M. Giunta; V. Glagolev; D. Glenzinski; M. Gold; N. Goldschmidt; A. Golossanov; G. Gomez; G. Gomez-Ceballos; M. Goncharov; O. González; I. Gorelov; A. T. Goshaw; K. Goulianos; A. Gresele; S. Grinstein; C. Grosso-Pilcher; U. Grundler; J. Guimaraes da Costa; Z. Gunay-Unalan; C. Haber; K. Hahn; S. R. Hahn; E. Halkiadakis; B.-Y. Han; J. Y. Han; R. Handler; F. Happacher; K. Hara; D. Hare; M. Hare; S. Harper; R. F. Harr; R. M. Harris; M. Hartz; K. Hatakeyama; J. Hauser; C. Hays; M. Heck; A. Heijboer; B. Heinemann; J. Heinrich; C. Henderson; M. Herndon; J. Heuser; S. Hewamanage; D. Hidas; C. S. Hill; D. Hirschbuehl; A. Hocker; S. Hou; M. Houlden; S.-C. Hsu; B. T. Huffman; R. E. Hughes; U. Husemann; J. Huston; J. Incandela; G. Introzzi; M. Iori; A. Ivanov; B. Iyutin; E. James; B. Jayatilaka; D. Jeans; E. J. Jeon; S. Jindariani; W. Johnson; M. Jones; K. K. Joo; S. Y. Jun; J. E. Jung; T. R. Junk; T. Kamon; D. Kar; P. E. Karchin; Y. Kato; R. Kephart; U. Kerzel; V. Khotilovich; B. Kilminster; D. H. Kim; H. S. Kim; J. E. Kim; M. J. Kim; S. B. Kim; S. H. Kim; Y. K. Kim; N. Kimura; L. Kirsch; S. Klimenko; M. Klute; B. Knuteson; B. R. Ko; S. A. Koay; K. Kondo; D. J. Kong; J. Konigsberg; A. Korytov; A. V. Kotwal; J. Kraus; M. Kreps; J. Kroll; N. Krumnack; M. Kruse; V. Krutelyov; T. Kubo; S. E. Kuhlmann; T. Kuhr; N. P. Kulkarni; Y. Kusakabe; S. Kwang; A. T. Laasanen; S. Lai; S. Lami; S. Lammel; M. Lancaster; R. L. Lander; K. Lannon; A. Lath; G. Latino; I. Lazzizzera; T. Lecompte; J. Lee; Y. J. Lee; S. W. Lee; R. Lefčvre; N. Leonardo; S. Leone; S. Levy; J. D. Lewis; C. S. Lin; M. Lindgren; E. Lipeles; A. Lister; D. O. Litvintsev; T. Liu; N. S. Lockyer; A. Loginov; M. Loreti; L. Lovas; R.-S. Lu; D. Lucchesi; J. Lueck; C. Luci; P. Lujan; P. Lukens; G. Lungu; L. Lyons; J. Lys; R. Lysak; E. Lytken; P. Mack; D. MacQueen; R. Madrak; K. Maeshima; K. Makhoul; T. Maki; P. Maksimovic; S. Malde; S. Malik; G. Manca; A. Manousakis; F. Margaroli; C. Marino; A. Martin; M. Martin; V. Martin; M. Martínez; R. Martínez-Ballarín; T. Maruyama; P. Mastrandrea; T. Masubuchi; M. E. Mattson; P. Mazzanti; K. S. McFarland; P. McIntyre; R. McNulty; A. Mehta; P. Mehtala; S. Menzemer; A. Menzione; P. Merkel; C. Mesropian; A. Messina; T. Miao; N. Miladinovic; J. Miles; R. Miller; C. Mills; M. Milnik; A. Mitra; G. Mitselmakher; H. Miyake; S. Moed; N. Moggi; C. S. Moon; R. Moore; M. Morello; P. Movilla Fernandez; J. Mülmenstädt; A. Mukherjee; Th. Muller; R. Mumford; P. Murat; M. Mussini; J. Nachtman; Y. Nagai; A. Nagano; J. Naganoma; K. Nakamura; I. Nakano; A. Napier; V. Necula; C. Neu; M. S. Neubauer; J. Nielsen; L. Nodulman; M. Norman; O. Norniella; E. Nurse; S. H. Oh

2008-01-01

261

Measurement requirements and techniques for degradation studies and lifetime prediction testing of photovoltaic modules  

NASA Technical Reports Server (NTRS)

Tests of weathering and aging behavior are being developed to characterize the degradation and predict the lifetimes of low-cost photovoltaic arrays. Environmental factors which affect array performance include UV radiation, thermal energy, water, oxygen (generally involved in synergistic effects with UV radiation or high temperatures), physical stress, pollutants (oxides of nitrogen, sulfur dioxide and ozone), abrasives and dirt. A survey of photovoltaic array testing has shown the need to establish quantitative correlations between certain measurable properties (carbonyl formation, glass transition temperature, and molecular weight change) and modes of degradation and failure.

Noel, G. T.; Sliemers, F. A.; Derringer, G. C.; Wood, V. E.; Wilkes, K. E.; Gaines, G. B.; Carmichael, D. C.

1978-01-01

262

Positron and electron collisions with nitrous oxide: Measured and calculated cross sections  

NASA Astrophysics Data System (ADS)

We present cross-section results from an experimental and theoretical study on positron scattering from nitrous oxide. Total cross sections (TCSs) have been measured at incident energies between 0.1 and 70 eV with a linear-transmission-based positron spectrometer. Elastic differential and integral cross sections, as well as inelastic integral cross sections and TCSs, have been computed with two different theoretical approaches: the independent atom model with screening-corrected additivity rule (IAM-SCAR), at energies in the 1- to 1000-eV range, and the Schwinger multichannel method at energies between 0.1 and 10 eV. Note that the latter method specifically reports cross sections for the elastic channel. We find good qualitative agreement between the theories and the TCS experiment at all common energies. That level of accord is found to also become quantitative above the ionization energy of nitrous oxide. Electron-impact TCSs calculated with the IAM-SCAR approach are also presented and compared to the existing results in order to uncover any similarities or differences in the scattering processes between these two leptons and nitrous oxide.

Chiari, Luca; Zecca, Antonio; Trainotti, Emanuele; García, Gustavo; Blanco, Francisco; Bettega, Márcio H. F.; d'A. Sanchez, Sergio; do N. Varella, Márcio T.; Lima, Marco A. P.; Brunger, M. J.

2013-08-01

263

Muon Lifetime Measurement and Introduction to the use of FPGAs in Experimental Physics  

NASA Astrophysics Data System (ADS)

During the laboratory sessions at the Workshop, the students used a simple experimental setup to measure the muon lifetime with a 10% statistical error. The muon detector consisted of a sealed container, filled with liquid scintillator, coupled to a 2.5? photomultiplier (PMT). A personal computer (PC) was used to control a digital oscilloscope which directly measured the time interval between two consecutive PMT pulses in a time window of 20 ?s. The students were also introduced to the use of root to analyze the muon data and to measure the muon lifetime. They were also presented with a basic introduction to the application of field-programmable gate arrays (FPGAs) in data acquisition (DAQ) systems by means of examples. We started with a brief introduction to the VHDL language and the software package used to program FPGAs and PROMs on a commercial FPGA development board. They learned to program FPGAs for handling data transfers using the RS-232 port of a PC. They were also introduced to the concepts of circular RAMs (Random Access Memory) and FIFO (First-In First-Out) memories in the context of fast and efficient DAQ systems. We emphasized the way in which inexpensive FPGA-based electronics replaces the use of traditionally used electronics modules, such as NIM, CAMAC, FASTBUS, VME, etc., to construct fast and powerful DAQ systems.

Villaseńor, L.

2008-07-01

264

In vivo mitochondrial oxygen tension measured by a delayed fluorescence lifetime technique.  

PubMed

Mitochondrial oxygen tension (mitoPO(2)) is a key parameter for cellular function, which is considered to be affected under various pathophysiological circumstances. Although many techniques for assessing in vivo oxygenation are available, no technique for measuring mitoPO(2) in vivo exists. Here we report in vivo measurement of mitoPO(2) and the recovery of mitoPO(2) histograms in rat liver by a novel optical technique under normal and pathological circumstances. The technique is based on oxygen-dependent quenching of the delayed fluorescence lifetime of protoporphyrin IX. Application of 5-aminolevulinic acid enhanced mitochondrial protoporphyrin IX levels and induced oxygen-dependent delayed fluorescence in various tissues, without affecting mitochondrial respiration. Using fluorescence microscopy, we demonstrate in isolated hepatocytes that the signal is of mitochondrial origin. The delayed fluorescence lifetime was calibrated in isolated hepatocytes and isolated perfused livers. Ultimately, the technique was applied to measure mitoPO(2) in rat liver in vivo. The results demonstrate mitoPO(2) values of approximately 30-40 mmHg. mitoPO(2) was highly sensitive to small changes in inspired oxygen concentration around atmospheric oxygen level. Ischemia-reperfusion interventions showed altered mitoPO(2) distribution, which flattened overall compared to baseline conditions. The reported technology is scalable from microscopic to macroscopic applications, and its reliance on an endogenous compound greatly enhances its potential field of applications. PMID:18641065

Mik, Egbert G; Johannes, Tanja; Zuurbier, Coert J; Heinen, Andre; Houben-Weerts, Judith H P M; Balestra, Gianmarco M; Stap, Jan; Beek, Johan F; Ince, Can

2008-10-01

265

Recent Progress Towards a Measurement of the Neutron Lifetime Using Magnetically Trapped Ultracold Neutrons  

NASA Astrophysics Data System (ADS)

Free neutron beta decay is a fundamental process in the Standard Model that can be used to test the weak interaction as well as provide information about primordial ^4He abundance. Recent precision measurements of the neutron lifetime have led to reduced confidence in the absolute value of this parameter; due presumably to unknown systematic effects. This work seeks to measure the neutron lifetime using a different technique that employs a superconducting magnetic trap to confine ultracold neutrons. Neutrons are loaded into the trap through the superthermal technique where 1 mEv neutrons down scatter from phonons in liquid helium losing the majority of their energy. Neutrons in the appropriate spin state are then confined by the static magnetic field. During the past year, over 400 run cycles of data were collected using the upgraded apparatus. Analysis of previous data sets was limited due to large numbers of background events relative to the neutron decay signal. An increased number of trapped neutrons as well as a analysis using pulse shape discrimination allows one to significantly increase the overall precision of the measurement. Details of this ongoing analysis will be presented with preliminary results.

Schelhammer, K. W.; Huffer, C. R.; Huffman, P. R.; Marley, D. E.; Coakley, K. J.; Huber, Michael; Hughes, P. P.; Mumm, H. P.; Thompson, A. K.; Yue, A. T.; Abrams, N. C.

2012-03-01

266

A measurement of the lambda_b lifetime at the D0 experiment  

SciTech Connect

This thesis describes a measurement of the lifetime of the {Lambda}{sub b}{sup 0} baryon, performed using data from proton-antiproton collisions at a centre of mass energy of 1.96 TeV. The decay {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{mu}{sup -}{ovr P{nu}}{sub {mu}}X was reconstructed in approximately 1.3 fb{sup -1} of data recorded by the D0 detector in 2002-2006 during Run II of the Fermilab Tevatron collider. A signal of 4437 {+-} 329 {Lambda}{sub c}{sup +}{mu}{sup -} pairs was obtained, and the {Lambda}{sub b}{sup 0} lifetime was measured using a binned {chi}{sup 2} fit, which gives a value {tau}({Lambda}{sub b}{sup 0}) = 1.290{sub -0.110}{sup +0.119}(stat){sub -0.091}{sup +0.085}(syst) ps. This result is consistent with the world average and is one of the most precise measurements of this quantity.

Lewin, Marcus Philip; /Lancaster U.

2007-07-01

267

In Vivo Mitochondrial Oxygen Tension Measured by a Delayed Fluorescence Lifetime Technique  

PubMed Central

Mitochondrial oxygen tension (mitoPO2) is a key parameter for cellular function, which is considered to be affected under various pathophysiological circumstances. Although many techniques for assessing in vivo oxygenation are available, no technique for measuring mitoPO2 in vivo exists. Here we report in vivo measurement of mitoPO2 and the recovery of mitoPO2 histograms in rat liver by a novel optical technique under normal and pathological circumstances. The technique is based on oxygen-dependent quenching of the delayed fluorescence lifetime of protoporphyrin IX. Application of 5-aminolevulinic acid enhanced mitochondrial protoporphyrin IX levels and induced oxygen-dependent delayed fluorescence in various tissues, without affecting mitochondrial respiration. Using fluorescence microscopy, we demonstrate in isolated hepatocytes that the signal is of mitochondrial origin. The delayed fluorescence lifetime was calibrated in isolated hepatocytes and isolated perfused livers. Ultimately, the technique was applied to measure mitoPO2 in rat liver in vivo. The results demonstrate mitoPO2 values of ?30–40 mmHg. mitoPO2 was highly sensitive to small changes in inspired oxygen concentration around atmospheric oxygen level. Ischemia-reperfusion interventions showed altered mitoPO2 distribution, which flattened overall compared to baseline conditions. The reported technology is scalable from microscopic to macroscopic applications, and its reliance on an endogenous compound greatly enhances its potential field of applications. PMID:18641065

Mik, Egbert G.; Johannes, Tanja; Zuurbier, Coert J.; Heinen, Andre; Houben-Weerts, Judith H. P. M.; Balestra, Gianmarco M.; Stap, Jan; Beek, Johan F.; Ince, Can

2008-01-01

268

Setup and operation of gamma-ray measurement systems to maximize detector lifetime and stability  

NASA Astrophysics Data System (ADS)

The details for optimizing gamma-ray measurement system for specific applications are not always well understood. The setup and operation of a system plays an important role in performance aspects such as maximizing detector lifetime, stability and minimizing the signal to noise ratio. In addition to system setup and operation, the effects of scintillation detector design and accompanying electronics (PMT) are discussed with respect to both gross counting and spectroscopy measurements in order to obtain reliable results. Data has been taken with various sodium iodide scintillation detectors to study system stability during transient such as power cycling and count rate fluctuations. These fluctuations may introduce substantial measurement uncertainty, and if not accounted for will propagate into an analyses. The above transients can also affect the detector lifetime, and if the system conditions are monitored properly, they can be used as a predictive tool for determining the useful life of a detector. Data is also presented to examine counting statistics in an overlapping spectrum as a function of spectral resolution and count rate. The objective is to determine the optimum counting time for the spectrum to reach a statistically stable shape. The data is reduced by examining the standard deviation of fitted Gaussian curves at ten second intervals. The result is a contour plat showing the time needed to reach stability, which increase with spectral resolution and decrease with a rising count rate.

Penn, David G.; Grodsinsky, Carlos M.

1999-10-01

269

Uptake of aluminium into Arabidopsis root cells measured by fluorescent lifetime imaging  

PubMed Central

Background and Aims Measuring the Al3+ uptake rate across the plasma membrane of intact root cells is crucial for understanding the mechanisms and time-course of Al toxicity in plants. However, a reliable method with the sufficient spatial and temporal resolution to estimate Al3+ uptake in intact root cells does not exist. Methods In the current study, fluorescent lifetime imaging (FLIM) analysis was used to quantify Al3+ uptake in the root-cell cytoplasm in vivo. This was performed via the estimation of the fluorescence lifetime of Al–lumogallion {5-chloro-3[(2,4-dihydroxyphenyl)azo]-2-hydroxybenzenesulfonic acid} complexes and measurements of intracellular pH while exposing arabidopsis seedlings to acidic and Al3+ stresses. Key Results The lifetime of Al–lumogallion complexes fluorescence is pH-dependent. The primary sites for Al3+ entry are the meristem and distal elongation zones, while Al3+ uptake via the cortex and epidermis of the mature root zone is limited. The maximum rates of Al uptake into the cytoplasm (2–3 ľmol m?3 min?1 for the meristematic root zone and 3–7 ľmol m?3 min?1 for the mature zone) were observed after a 30-min exposure to 100 ľm AlCl3 (pH 4ˇ2). Intracellular Al concentration increased to 0ˇ4 ľm Al within the first 3 h of exposure to 100 ľm AlCl3. Conclusions FLIM analysis of the fluorescence of Al–lumogallion complexes can be used to reliably quantify Al uptake in the cytoplasm of intact root cells at the initial stages of Al3+ stress. PMID:19401291

Babourina, Olga; Rengel, Zed

2009-01-01

270

Monte Carlo modelling of positron transport in real world applications  

NASA Astrophysics Data System (ADS)

Due to the unstable nature of positrons and their short lifetime, it is difficult to obtain high positron particle densities. This is why the Monte Carlo simulation technique, as a swarm method, is very suitable for modelling most of the current positron applications involving gaseous and liquid media. The ongoing work on the measurements of cross-sections for positron interactions with atoms and molecules and swarm calculations for positrons in gasses led to the establishment of good cross-section sets for positron interaction with gasses commonly used in real-world applications. Using the standard Monte Carlo technique and codes that can follow both low- (down to thermal energy) and high- (up to keV) energy particles, we are able to model different systems directly applicable to existing experimental setups and techniques. This paper reviews the results on modelling Surko-type positron buffer gas traps, application of the rotating wall technique and simulation of positron tracks in water vapor as a substitute for human tissue, and pinpoints the challenges in and advantages of applying Monte Carlo simulations to these systems.

Marjanovi?, S.; Bankovi?, A.; Šuvakov, M.; Petrovi?, Z. Lj

2014-05-01

271

Measurement of the average {ital B} hadron lifetime in {ital Z}{sup 0} decays using reconstructed vertices  

SciTech Connect

We report a measurement of the average {ital B} hadron lifetime using data collected with the SLD detector at the SLAC Linear Collider in 1993. An inclusive analysis selected three-dimensional vertices with {ital B} hadron lifetime information in a sample of 50{times}10{sup 3} {ital Z}{sup 0} decays. A lifetime of 1.564{plus_minus}0.030(stat){plus_minus}0.036(syst) ps was extracted from the decay length distribution of these vertices using a binned maximum likelihood method. {copyright} {ital 1995} {ital The} {ital American} {ital Physical} {ital Society}.

Abe, K.; Abt, I.; Ahn, C.J.; Akagi, T.; Allen, N.J.; Ash, W.W.; Aston, D.; Baird, K.G.; Baltay, C.; Band, H.R.; Barakat, M.B.; Baranko, G.; Bardon, O.; Barklow, T.; Bazarko, A.O.; Ben-David, R.; Benvenuti, A.C.; Bilei, G.M.; Bisello, D.; Blaylock, G.; Bogart, J.R.; Bolton, T.; Bower, G.R.; Brau, J.E.; Breidenbach, M.; Bugg, W.M.; Burke, D.; Burnett, T.H.; Burrows, P.N.; Busza, W.; Calcaterra, A.; Caldwell, D.O.; Calloway, D.; Camanzi, B.; Carpinelli, M.; Cassell, R.; Castaldi, R.; Castro, A.; Cavalli-Sforza, M.; Church, E.; Cohn, H.O.; Coller, J.A.; Cook, V.; Cotton, R.; Cowan, R.F.; Coyne, D.G.; D`Oliveira, A.; Damerell, C.J.S.; Daoudi, M.; De Sangro, R.; De Simone, P.; Dell`Orso, R.; Dima, M.; Du, P.Y.C.; Dubois, R.; Eisenstein, B.I.; Elia, R.; Falciai, D.; Fan, C.; Fero, M.J.; Frey, R.; Furuno, K.; Gillman, T.; Gladding, G.; Gonzalez, S.; Hallewell, G.D.; Hart, E.L.; Hasegawa, Y.; Hedges, S.; Hertzbach, S.S.; Hildreth, M.D.; Huber, J.; Huffer, M.E.; Hughes, E.W.; Hwang, H.; Iwasaki, Y.; Jackson, D.J.; Jacques, P.; Jaros, J.; Johnson, A.S.; Johnson, J.R.; Johnson, R.A.; Junk, T.; Kajikawa, R.; Kalelkar, M.; Kang, H.J.; Karliner, I.; Kawahara, H.; Kendall, H.W.; Kim, Y.; King, M.E.; King, R.; Kofler, R.R.; Krishna, N.M.; Kroeger, R.S.; Labs, J.F.; Langston, M.; Lath, A.; Lauber, J.A.; Leith, D.W.G.S.; Liu, M.X.; Liu, X.; Loreti, M.; Lu, A.; Lynch, H.L.; Ma, J.; Mancinelli, G.; Manly, S.; Mantovani, G.; Markiewicz, T.W.; Maruyama, T.; Massetti, R.; Masuda, H.; Mazzucato, E.; McKemey, A.K.; Meadows, B.T.; Messner, R.; Mockett, P.M.; Moffeit, K.C.; Mours, B.; Mueller, G.; Muller, D.; Nagamine, T.; Nauenberg, U.; Neal, H.; Nussbaum, M.; Ohnishi, Y.; Osborne, L.S.; Panvini, R.S.; Park, H.; Pavel, T.J.; Peruzzi, I.; Piccolo, M.; Piemontese, L.; Pieroni, E.; Pitts, K.T.; Plano, R.J.; Prepost, R.; Prescott, C.Y.; Punkar, G.D.; Quigley, J.; Ratcliff, B.N.; Reeves, T.W.; Reidy, J.; Rensing, P.E.; Rochester, L.S.; Rothberg, J.E.; Rowson, P.C.; Russell, J.J.; (SLD Collabora..

1995-11-13

272

A new differentially pumped plunger device to measure excited-state lifetimes in proton emitting nuclei  

NASA Astrophysics Data System (ADS)

A new plunger device has been designed and built to measure the lifetimes of unbound states in exotic nuclei beyond the proton drip-line. The device has been designed to work in both vacuum and dilute-gas environments made possible through the introduction of a low-voltage stepping motor. DPUNS will be used in conjunction with the gas-filled separator RITU and the vacuum separator MARA at the accelerator laboratory of the University of Jyväskylä, Finland, to measure the lifetimes of excited states with low population cross-sections. This is achieved by eliminating the need for a carbon foil to isolate the helium gas of RITU from the beam line thus reducing the background from beam-foil reactions. The inclusion of a high-sampling rate data acquisition card increases further the sensitivity of the device. The plunger will be used to address many key facets of nuclear structure physics with particular emphasis on the effect of deformation on proton emission rates.

Taylor, M. J.; Cullen, D. M.; Smith, A. J.; McFarlane, A.; Twist, V.; Alharshan, G. A.; Procter, M. G.; Braunroth, T.; Dewald, A.; Ellinger, E.; Fransen, C.; Butler, P. A.; Scheck, M.; Joss, D. T.; Saygi, B.; McPeake, C. G.; Grahn, T.; Greenlees, P. T.; Jakobsson, U.; Jones, P.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nieminen, P.; Pakarinen, J.; Peura, P.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J.

2013-04-01

273

Lifetime measurement of metastable fluorine atoms using electron cyclotron resonance plasma source  

SciTech Connect

The authors have measured the lifetime of metastable state (3s {sup 4}P{sub 5/2}) of F atoms by resonant laser-induced fluorescence method. For this experiment, a special 2.45 GHz electron cyclotron resonance (ECR) plasma source, which is highly efficient in F radical generation and free from magnetic field leakage in front of the beam-emitting orifice, has been developed. Using the ECR plasma gun, the authors observed a precision fluorescence spectrum related to 3p {sup 4}D{sub 7/2}{sup 0}(F=4){yields}3s {sup 4}P{sub 5/2}(F=3) transition of F radicals, which made it possible to experimentally determine the longitudinal velocity distribution and the angular spread of the F radical beam. Based on these measured beam characteristics, the authors extracted a true decay curve of fluorescence intensity as a function of distance from the source and determined the lifetime of F metastable state (3s {sup 4}P{sub 5/2}) as 7.3{+-}0.5 {mu}s.

Shimizu, Masao; Ohmi, Hiromasa; Kakiuchi, Hiroaki; Yasutake, Kiyoshi [Yasu Semiconductor Corporation, 686-1 Ichimiyake, Yasu-cho, Yasu-gun, Shiga 520-2632 (Japan); Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2006-11-15

274

Measurement of the B+- lifetime and top quark identification using secondary vertex b-tagging  

SciTech Connect

This dissertation presents a preliminary measurement of the B{sup {+-}} lifetime through the full reconstruction of its decay chain, and the identification of top quark production in the electron plus jets channel using the displaced vertex b-tagging method. Its main contribution is the development, implementation and optimization of the Kalman filter algorithm for vertex reconstruction, and of the displaced vertex technique for tagging jets arising from b quark fragmentation, both of which have now become part of the standard D0 reconstruction package. These two algorithms fully exploit the new state-of-the-art tracking detectors, recently installed as part of the Run 2 D0 upgrade project. The analysis is based on data collected during Run 2a at the Fermilab Tevatron p{bar p} Hadron Collider up to April 2003, corresponding to an integrated luminosity of 60 pb{sup -1}. The measured B meson lifetime of {tau} = 1.57 {+-} 0.18 ps is in agreement with the current world average, with a competitive level of precision expected when the full data sample becomes available.

Schwartzman, Ariel G.; /Buenos Aires U.; ,

2004-02-01

275

Fluorescence Lifetime Measurements and Biological Imaging Mikhail Y. Berezin* and Samuel Achilefu*  

E-print Network

Molecular Probes and Their Lifetimes 2662 6.1. Small Organic Fluorophores 2662 6.1.1. Background Elimination. Fluorescence Lifetime Imaging Applications 2671 7.1. Cell Biology 2672 7.2. Tissue and Small Animal Lifetime.1.5. FRET with Small Organic Fluorophores 2666 6.1.6. Self-Quenching and Aggregation of Small Molecules 2667

Larson-Prior, Linda

276

Temperature dependence of positron trapping at grain boundaries  

NASA Astrophysics Data System (ADS)

Positron lifetime spectra were measured for fine-grained samples of the superplastic alloy Al - 5 wt% Ca - 5 wt% Zn at temperatures from 10 to 295 K. The lifetime attributed to annihilation from traps at the grain interfaces was found to increase with the temperature, while the corresponding intensity was observed to decrease. The quantitative analysis of the experimental results according to the diffusion-trapping model (Dupasquier et al 1993 Phys. Rev. B 48 9235) leads to the following conclusions: (a) the positron diffusion coefficient in the alloy matrix (a solid solution of Zn and Ca in Al) is limited by positron - phonon scattering as well as by positron - impurity interaction; (b) the phonon-associated term in the reciprocal of the diffusion coefficient is dominant at room temperature and scales at other temperatures with the same power law as holds for pure Al (Soininen et al 1990 Phys. Rev. B 41 6277); (c) the term associated with positron - impurity scattering is small except at very low temperatures, but the positron - impurity interaction seems to give a localization effect that is more important than the scattering; and (d) the specific trapping rate at the interface has a negative temperature dependence, as expected for trapping mediated by a precursor shallow state.

Aina, S.; Dupasquier, A.; Folegati, P.; DeDiego, N.; del Rio, J.; Somoza, A.; Valli, M.

1997-08-01

277

Mechanical durability of polymeric coatings studied by positron annihilation spectroscopy: correlation between cyclic loading and free volumes  

NASA Astrophysics Data System (ADS)

The mechanical durability of seven commercially polymeric coatings is investigated using slow positron beam techniques to monitor changes in sub-nanometer defects during the process of cyclic loading. Doppler broadened energy spectra and positron annihilation lifetime (PAL) measurements were performed as a function of the slow positron energy at different periods of cycling loading. The positron annihilation dada show that both S-defect parameter and o-positronium (Ps) lifetime decrease as the loading cycle increases. The results indicate a loss of free volumes due to the loss of mechanical durability by cyclic loading. A direct correlation between the loss of S-defect parameter and the period of loading cycle is observed. This is interpreted as that durability of polymeric coatings is controlled by the atomic level free volumes. It is shown that the slow positron beam is a very successful probe in detecting the very early stages of coating degradation due to mechanical processes.

Chen, H.; Peng, Q.; Huang, Y. Y.; Zhang, R.; Mallon, P. E.; Zhang, J.; Li, Y.; Wu, Y.; Richardson, J. R.; Sandreczki, T. C.; Jean, Y. C.; Suzuki, R.; Ohdaira, T.

2002-06-01

278

Excited-Level Lifetimes and Hyperfine-Structure Measurements on Ions using Collinear Laser Ion-Beam Spectroscopy  

E-print Network

The mean lifetimes tau of the Ca II 4p P-2(1/2) and 4p P-2(3/2) levels, and the Cl-35 II 4p' F-1(3) level, have been measured by a variant of the collinear laser-ion-beam lifetime technique applied previously to the Ar II 4p' F-2(7/2)o level [Jian...

Jin, J.; Church, David A.

1994-01-01

279

High-resolution positron Q-value measurements and nuclear-structure studies far from the stability line. Progress report  

SciTech Connect

Extensive data analysis and theoretical analysis has been done to complete the extensive decay scheme investigation of /sup 206/ /sup 208/Fr and the level structures of /sup 206/ /sup 208/Rn. A final version of a journal article is presented in preprint form. Extensive Monte Carlo calculations have been made to correct the end point energies of positron spectra taken with intrinsic Ge detectors for annihilation radiation interferences. These calculations were tested using the decay of /sup 82/Sr which has previously measured positron branches. This technique was applied to the positron spectra collected at the on-line UNISOR isotope separator. The reactions used were /sup 60/Ni(/sup 20/Ne;p2n)/sup 77/Rb and /sup 60/Ni(/sup 20/Ne;pn)/sup 78/Rb. Values for 5, ..gamma..-..beta../sup +/ coincidence positron end point energies are given for the decay of /sup 77/Rb. The implied Q-value is 5.075 +- 0.010 MeV. A complete paper on the calculated corrections is presented. A flow chart of a more complete program which accounts for positrons scattering out of the detector and for bremsstralung radiation is also presented. End-point energies of four ..beta../sup +/ branches in /sup 77/Rb are given as well as a proposed energy level scheme of /sup 75/Kr based on ..gamma..-..gamma.. coincidence data taken at UNISOR.

Avignone, F.T. III.

1981-02-28

280

Counting rate measurements for lifetime experiments using the RDDS method with the new generation ?-ray array AGATA  

NASA Astrophysics Data System (ADS)

The differential Recoil Distance Doppler Shift (RDDS) method after multinucleon transfer (MNT) reactions to measure lifetimes of excited states in neutron-rich nuclei requires the use of a thick energy degrader for the recoiling ejectiles that are then detected in a spectrometer. This type of measurements greatly benefits from the use of the new generation segmented ?-ray detectors, such as the AGATA demonstrator which offers unprecedented energy and angular resolutions. In order to make an optimized choice of the material and the thickness of the degrader for lifetime measurements using the RDDS method after MNT, an experiment has been performed with the AGATA demonstrator. Counting rate measurements for different degraders are presented.

Goasduff, A.; Valiente-Dobón, J. J.; Lunardi, S.; Haas, F.; Gadea, A.; de Angelis, G.; Bazzacco, D.; Courtin, S.; Farnea, E.; Gottardo, A.; Michelagnoli, C.; Mengoni, D.; Napoli, D. R.; Recchia, F.; Sahin, E.; Ur, C. A.

2014-09-01

281

CFCI3 (CFC-11): UV Absorption Spectrum Temperature Dependence Measurements and the Impact on Atmospheric Lifetime and Uncertainty  

NASA Technical Reports Server (NTRS)

CFCl3 (CFC-11) is both an atmospheric ozone-depleting and potent greenhouse gas that is removed primarily via stratospheric UV photolysis. Uncertainty in the temperature dependence of its UV absorption spectrum is a significant contributing factor to the overall uncertainty in its global lifetime and, thus, model calculations of stratospheric ozone recovery and climate change. In this work, the CFC-11 UV absorption spectrum was measured over a range of wavelength (184.95 - 230 nm) and temperature (216 - 296 K). We report a spectrum temperature dependence that is less than currently recommended for use in atmospheric models. The impact on its atmospheric lifetime was quantified using a 2-D model and the spectrum parameterization developed in this work. The obtained global annually averaged lifetime was 58.1 +- 0.7 years (2 sigma uncertainty due solely to the spectrum uncertainty). The lifetime is slightly reduced and the uncertainty significantly reduced from that obtained using current spectrum recommendations

Mcgillen, Max R.; Fleming, Eric L.; Jackman, Charles H.; Burkholder, James B.

2014-01-01

282

CFCl3 (CFC-11): UV absorption spectrum temperature dependence measurements and the impact on its atmospheric lifetime and uncertainty  

NASA Astrophysics Data System (ADS)

(CFC-11) is both an atmospheric ozone-depleting and potent greenhouse gas that is removed primarily via stratospheric UV photolysis. Uncertainty in the temperature dependence of its UV absorption spectrum is a significant contributing factor to the overall uncertainty in its global lifetime and, thus, model calculations of stratospheric ozone recovery and climate change. In this work, the CFC-11 UV absorption spectrum was measured over a range of wavelength (184.95-230 nm) and temperature (216-296 K). We report a spectrum temperature dependence that is less than that currently recommended for use in atmospheric models. The impact on its atmospheric lifetime was quantified using a 2-D model and the spectrum parameterization developed in this work. The calculated global annually averaged lifetime was 58.1 ą 0.7 years (2? uncertainty due solely to the spectrum uncertainty). The lifetime is slightly reduced and the uncertainty significantly reduced from that obtained using current UV spectrum recommendations.

McGillen, Max R.; Fleming, Eric L.; Jackman, Charles H.; Burkholder, James B.

2013-09-01

283

Free volume change in Zr50Cu40Al10 glassy alloy by the annealing studied by positron annihilation spectroscopy  

NASA Astrophysics Data System (ADS)

It is well known that structural relaxation in a bulk metallic glass affects some properties such as viscosity, electrical conductivity, and ductility. The free volume in glassy alloy, which is open volume retained by rapidly solidification from liquid state, has a significant roll for those properties. In order to discuss the nature of free volume in a Zr50Cu40Al10 bulk metallic glass, positron lifetime measurements have been performed for this metallic glass before and after annealing, and all positron lifetime spectra have been decomposed into multi components as a size distribution function by use of CONTIN-PALS II program. The positron lifetime distribution for this metallic glass has a broad spectrum comparing to crystal metal including a single vacancy, and its average lifetime corresponds to the free volume size. This width of positron lifetime (free volume size) distribution decreases by the annealing at 673 K. This change of the positron lifetime distribution can be attributed to a free volume relaxation.

Ishii, A.; Hori, F.; Fukumoto, Y.; Iwase, A.; Yokoyama, Y.; Konno, T. J.

2011-01-01

284

Positron Annihilation Spectroscopy Study of Ni-Mn-Ga Ferromagnetic Shape Memory Alloys  

NASA Astrophysics Data System (ADS)

We have studied the role that vacancy type defects play in the martensitic transformation of Ni-Mn-Ga ferromagnetic shape memory alloys by means of positron lifetime spectroscopy. The measurements presented in this work have been performed in five ternary alloys. Three of them transform to modulated and two to non-modulated martensitic phases. With these five samples we cover a large range in composition. Positron experiments have been performed at room temperature after subsequent isochronal annealing at different temperatures and up to a maximum temperature of 600°C. Results show a large variation of the average positron lifetime value with the isochronal annealing temperature in non-modulated samples. However, the response in the modulated samples is quite different. The results are discussed in term of different type of positron trapping defects and their evolution with the annealing temperature. The present work shows a correlation between vacancy concentration and martensitic transformation temperature of ferromagnetic shape memory alloys.

Merida, David; Garcia, Jose Angel; Apińaniz, Estibaliz; Plazaola, Fernando; Sanchez-Alarcos, Vicente; Pérez-Landazábal, Jose Ignacio; Recarte, Vicente

285

Temperature dependence of positron annihilation at dislocations in Pb(Cd)  

NASA Astrophysics Data System (ADS)

We have measured the temperature dependence of positron lifetimes in a Pb96.1Cd3.9 alloy having a dislocation density large enough to significantly affect the e+e- annihilation spectra. These spectra were resolved into two unconstrained lifetimes in addition to a sourceterm lifetime. The longer of the two lifetimes, which is attributed to positrons localized by traps associated with dislocations, decreases with increasing sample temperature T at about 0.1 psec K-1 for 90<=T<=300 K. These data represent the first reported observation of a temperature-dependent lifetime of positrons localized at dislocation traps. It is proposed that the temperature dependence is principally due to atoms penetrating deeper into the traps as T is raised. We suggest that these atomic incursions also effect a negative contribution to the slope of the line-shape parameter S(T). Analysis of the data in terms of the two-state trapping model reveals (i) that both the trapping rate per unit dislocation density and the probability of annihilation occurring at the dislocation traps for constant dislocation density are weakly temperature dependent, and (ii) that during recovery anneals the total trapping rate decreases markedly, whereas little change is exhibited by the lifetime of the trapped positron.

Hu, C.-K.; Gruzalski, G. R.

1983-01-01

286

Measurement of the $B_c^+$ meson lifetime using $B_c^+ \\to J/\\psi\\mu^+\  

E-print Network

The precision measurement of the $B_c^+$ meson lifetime provides an essential test of the models describing the unique open-flavour state composed of two heavy quarks. It is also a necessary input for all measurements of $B_c^+$ production and decay branching fractions. The first measurement of the $B_c^+$ lifetime achieved by the LHCb Collaboration is presented in this Thesis. The data sample collected in 2012, in $pp$ collisions at a centre-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of 2 fb$^{-1}$, is analysed to select $B_c^+ \\to J/\\psi\\mu^+\

Anderlini, Lucio

287

Measuring protein interactions using Förster resonance energy transfer and fluorescence lifetime imaging microscopy.  

PubMed

The method of fluorescence lifetime imaging microscopy (FLIM) is a quantitative approach that can be used to detect Förster resonance energy transfer (FRET). The use of FLIM to measure the FRET that results from the interactions between proteins labeled with fluorescent proteins (FPs) inside living cells provides a non-invasive method for mapping interactomes. Here, the use of the phasor plot method to analyze frequency domain (FD) FLIM measurements is described, and measurements obtained from cells producing the 'FRET standard' fusion proteins are used to validate the FLIM system for FRET measurements. The FLIM FRET approach is then used to measure both homologous and heterologous protein-protein interactions (PPI) involving the CCAAT/enhancer-binding protein alpha (C/EBP?). C/EBP? is a transcription factor that controls cell differentiation, and localizes to heterochromatin where it interacts with the heterochromatin protein 1 alpha (HP1?). The FLIM-FRET method is used to quantify the homologous interactions between the FP-labeled basic leucine zipper (BZip) domain of C/EBP?. Then the heterologous interactions between the C/EBPa BZip domain and HP1a are quantified using the FRET-FLIM method. The results demonstrate that the basic region and leucine zipper (BZip) domain of C/EBP? is sufficient for the interaction with HP1? in regions of heterochromatin. PMID:23806643

Day, Richard N

2014-03-15

288

Lifetime Measurement of the 2{sup +}{sub 1} state in {sup 20}C  

SciTech Connect

Establishing how and when large N/Z values require modified or new theoretical tools is a major quest in nuclear physics. Here we report the first measurement of the lifetime of the 2{sup +}{sub 1} state in the near-dripline nucleus {sup 20}C. The deduced value of {tau}{sub #28;2{sup +}{sub 1}} = 9.8 ą 2.8(stat){sup +0.5}{sub ?1.1}(syst) ps gives a reduced transition probability of B(E2;2{sup +}{sub 1}{yields}0{sup +}{sub g.s.}) = 7.5{sup +3.0}{sub ?1.7}(stat){sup +1.0}{sub ?0.4}(syst) e{sup 2}fm{sup 4} in good agreement with a shell model calculation using isospin-dependent effective charges.

Petri, Marina-Kalliopi; Fallon, Paul; Macchiavelli, Augusto; Paschalis, Stephanos; Starosta, Krzysztof; Baugher, Travis; Bazin, Daniel; Cartegni, Lucia; Clark, Roderick; Crawford, Heather; Cromaz, Mario; Dewald, Alfred; Gade, Alexandra; Grinyer, Geoff; Gros, Sebastian; Hackstein, Matthias; Jeppesen, Hendrick; Lee, I-Yang; McDaniel, Sean; Miller, Doug; Rajabali, Mustafa; Ratkiewicz, Andrew; Rother, Wolfram; Voss, Phillip; Walsh, Kathleen Ann; Weisshaar, Dirk; Wiedeking, Mathis; Brown, Boyd Alex

2011-06-28

289

Measurement of the B0 and B+ Meson Lifetimes with Fully Reconstructed Hadronic Final States  

NASA Astrophysics Data System (ADS)

The B0 and B+ meson lifetimes have been measured in e+e- annihilation data collected in 1999 and 2000 with the BABAR detector at center-of-mass energies near the ?(4S) resonance. Events are selected in which one B meson is fully reconstructed in a hadronic final state while the second B meson is reconstructed inclusively. A combined fit to the B0 and the B+ decay time difference distributions yields ?B0 = 1.546+/-0.032(stat)+/-0.022(syst) ps, ?B+ = 1.673+/-0.032(stat)+/-0.023(syst) ps, and ?B+/?B0 = 1.082+/-0.026(stat)+/-0.012(syst).

Aubert, B.; Boutigny, D.; Gaillard, J.-M.; Hicheur, A.; Karyotakis, Y.; Lees, J. P.; Robbe, P.; Tisserand, V.; Palano, A.; Chen, G. P.; Chen, J. C.; Qi, N. D.; Rong, G.; Wang, P.; Zhu, Y. S.; Eigen, G.; Reinertsen, P. L.; Stugu, B.; Abbott, B.; Abrams, G. S.; Borgland, A. W.; Breon, A. B.; Brown, D. N.; Button-Shafer, J.; Cahn, R. N.; Clark, A. R.; Gill, M. S.; Gritsan, A.; Groysman, Y.; Jacobsen, R. G.; Kadel, R. W.; Kadyk, J.; Kerth, L. T.; Kluth, S.; Kolomensky, Yu. G.; Kral, J. F.; Leclerc, C.; Levi, M. E.; Liu, T.; Lynch, G.; Meyer, A. B.; Momayezi, M.; Oddone, P. J.; Perazzo, A.; Pripstein, M.; Roe, N. A.; Romosan, A.; Ronan, M. T.; Shelkov, V. G.; Telnov, A. V.; Wenzel, W. A.; Bright-Thomas, P. G.; Harrison, T. J.; Hawkes, C. M.; Knowles, D. J.; O'Neale, S. W.; Penny, R. C.; Watson, A. T.; Watson, N. K.; Deppermann, T.; Goetzen, K.; Koch, H.; Krug, J.; Kunze, M.; Lewandowski, B.; Peters, K.; Schmuecker, H.; Steinke, M.; Andress, J. C.; Barlow, N. R.; Bhimji, W.; Chevalier, N.; Clark, P. J.; Cottingham, W. N.; de Groot, N.; Dyce, N.; Foster, B.; McFall, J. D.; Wallom, D.; Wilson, F. F.; Abe, K.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Thiessen, D.; Jolly, S.; McKemey, A. K.; Tinslay, J.; Blinov, V. E.; Bukin, A. D.; Bukin, D. A.; Buzykaev, A. R.; Golubev, V. B.; Ivanchenko, V. N.; Korol, A. A.; Kravchenko, E. A.; Onuchin, A. P.; Salnikov, A. A.; Serednyakov, S. I.; Skovpen, Yu. I.; Telnov, V. I.; Yushkov, A. N.; Best, D.; Lankford, A. J.; Mandelkern, M.; McMahon, S.; Stoker, D. P.; Ahsan, A.; Arisaka, K.; Buchanan, C.; Chun, S.; Branson, J. G.; Macfarlane, D. B.; Prell, S.; Rahatlou, Sh.; Raven, G.; Sharma, V.; Campagnari, C.; Dahmes, B.; Hart, P. A.; Kuznetsova, N.; Levy, S. L.; Long, O.; Lu, A.; Richman, J. D.; Verkerke, W.; Witherell, M.; Yellin, S.; Beringer, J.; Dorfan, D. E.; Eisner, A. M.; Frey, A.; Grillo, A. A.; Grothe, M.; Heusch, C. A.; Johnson, R. P.; Kroeger, W.; Lockman, W. S.; Pulliam, T.; Sadrozinski, H.; Schalk, T.; Schmitz, R. E.; Schumm, B. A.; Seiden, A.; Turri, M.; Walkowiak, W.; Williams, D. C.; Wilson, M. G.; Chen, E.; Dubois-Felsmann, G. P.; Dvoretskii, A.; Hitlin, D. G.; Metzler, S.; Oyang, J.; Porter, F. C.; Ryd, A.; Samuel, A.; Weaver, M.; Yang, S.; Zhu, R. Y.; Devmal, S.; Geld, T. L.; Jayatilleke, S.; Mancinelli, G.; Meadows, B. T.; Sokoloff, M. D.; Barillari, T.; Bloom, P.; Dima, M. O.; Fahey, S.; Ford, W. T.; Johnson, D. R.; Nauenberg, U.; Olivas, A.; Park, H.; Rankin, P.; Roy, J.; Sen, S.; Smith, J. G.; van Hoek, W. C.; Wagner, D. L.; Blouw, J.; Harton, J. L.; Krishnamurthy, M.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Zhang, J.; Brandt, T.; Brose, J.; Colberg, T.; Dahlinger, G.; Dickopp, M.; Dubitzky, R. S.; Maly, E.; Müller-Pfefferkorn, R.; Otto, S.; Schubert, K. R.; Schwierz, R.; Spaan, B.; Wilden, L.; Behr, L.; Bernard, D.; Bonneaud, G. R.; Brochard, F.; Cohen-Tanugi, J.; Ferrag, S.; Roussot, E.; T'jampens, S.; Thiebaux, C.; Vasileiadis, G.; Verderi, M.; Anjomshoaa, A.; Bernet, R.; Khan, A.; Muheim, F.; Playfer, S.; Swain, J. E.; Falbo, M.; Borean, C.; Bozzi, C.; Dittongo, S.; Folegani, M.; Piemontese, L.; Treadwell, E.; Anulli, F.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Falciai, D.; Finocchiaro, G.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Xie, Y.; Zallo, A.; Bagnasco, S.; Buzzo, A.; Contri, R.; Crosetti, G.; Fabbricatore, P.; Farinon, S.; Lo Vetere, M.; Macri, M.; Monge, M. R.; Musenich, R.; Pallavicini, M.; Parodi, R.; Passaggio, S.; Pastore, F. C.; Patrignani, C.; Pia, M. G.; Priano, C.; Robutti, E.; Santroni, A.; Morii, M.; Bartoldus, R.; Dignan, T.; Hamilton, R.; Mallik, U.; Cochran, J.; Crawley, H. B.; Fischer, P.-A.; Lamsa, J.; Meyer, W. T.; Rosenberg, E. I.; Benkebil, M.; Grosdidier, G.; Hast, C.; Höcker, A.; Lacker, H. M.; Lepeltier, V.; Lutz, A. M.; Plaszczynski, S.; Schune, M. H.; Trincaz-Duvoid, S.; Valassi, A.; Wormser, G.; Bionta, R. M.; Brigljevi?, V.; Lange, D. J.; Mugge, M.; Shi, X.; van Bibber, K.; Wenaus, T. J.; Wright, D. M.; Wuest, C. R.; Carroll, M.; Fry, J. R.; Gabathuler, E.; Gamet, R.; George, M.; Kay, M.; Payne, D. J.; Sloane, R. J.; Touramanis, C.; Aspinwall, M. L.; Bowerman, D. A.; Dauncey, P. D.; Egede, U.; Eschrich, I.; Gunawardane, N. J.; Nash, J. A.; Sanders, P.; Smith, D.; Azzopardi, D. E.; Back, J. J.; Dixon, P.; Harrison, P. F.; Potter, R. J.; Shorthouse, H. W.; Strother, P.; Vidal, P. B.; Williams, M. I.; Cowan, G.; George, S.; Green, M. G.; Kurup, A.; Marker, C. E.; McGrath, P.; McMahon, T. R.; Ricciardi, S.; Salvatore, F.; Scott, I.; Vaitsas, G.; Brown, D.; Davis, C. L.; Allison, J.; Barlow, R. J.; Boyd, J. T.; Forti, A. C.; Fullwood, J.; Jackson, F.; Lafferty, G. D.; Savvas, N.; Simopoulos, E. T.; Weatherall, J. H.; Farbin, A.; Jawahery, A.; Lillard, V.; Olsen, J.; Roberts, D. A.

2001-11-01

290

Measurement of cosmic ray positron and negatron spectra between 50 and 800 MeV. Ph.D. Thesis  

NASA Technical Reports Server (NTRS)

A balloon-borne magnetic spectrometer was used to measure the spectra of cosmic ray positrons and negatrons at energies between 50 and 800 MeV. Comparisons of the separate positron and negatron spectra observed near the earth with their expected intensities in interstellar space can be used to investigate the complex (and variable) interaction of galactic cosmic rays with the expanding solar wind. The present measurements, which have established finite values or upper limits for the positron and negatron spectral between 50 and 800 MeV, have confirmed earlier evidence for the existence of a dominant component of negatrons from primary sources in the galaxy. The present results are shown to be consistent with the hypothesis that the positron component is in fact mainly attributable to collisions between cosmic ray nuclei and the interstellar gas. The estimate of the absolute intensities confirm the indications from neutron monitors that in 1972 the interplanetary cosmic ray intensities were already recovering toward their high levels observed in 1965.

Daugherty, J. K.

1974-01-01

291

In-situ minority carrier recombination lifetime measurements at radiation sources for rad-hard IR detector materials  

NASA Astrophysics Data System (ADS)

Minority carrier recombination lifetime (MCRL) is a key material parameter for space-based infrared (IR) detector performance affecting both dark current and responsivity. Displacement damage due to energetic massive particles in space environments, such as protons, can significantly degrade the recombination lifetime, thereby reducing detector performance. Therefore, characterizing the change in MCRL with proton dose is of general interest from a radiation-hardness perspective. So-called "bag tests," or measurements taken prior to and following room temperature proton irradiation of the device, are often of limited value to MCRL characterization since thermal annealing effects may be present. Here, progress toward a portable MCRL measurement system employing time resolved photoluminescence (TRPL) is presented. This system can be taken to remote radiation sources where irradiation can be performed on samples followed by TRPL measurements while maintaining temperature throughout. Ideally, this system permits measurement of a lifetime radiation damage factor constant, or the change in lifetime with step-wise changes in proton dose, which is a measure of the defect introduction rate. The pulsed-laser driven TRPL measurement system is able to interrogate IR materials of interest mounted in an optical cryostat held indefinitely at a desired temperature. A system description is given and results of verification measurements are discussed for several IR detector materials.

Jenkins, Geoffrey D.; Morath, Christian P.; Cowan, Vincent M.

2014-09-01

292

Study of ageing in Al-Mg-Si alloys by positron annihilation spectroscopy  

NASA Astrophysics Data System (ADS)

In many common Al-Mg-Si alloys (6000 series) intermediate storage at or near ‘room temperature’ after solutionising leads to pronounced changes of the precipitation kinetics during the ensuing artificial ageing step at ?180 °C. This is not only an annoyance in production, but also a challenge for researchers. We studied the kinetics of natural ‘room temperature’ ageing (NA) in Al-Mg-Si alloys by means of various different techniques, namely electrical resistivity and hardness measurement, thermoanalysis and positron lifetime and Doppler broadening (DB) spectroscopy to identify the stages in which the negative effect of NA on artificial ageing might appear. Positron lifetime measurements were carried out in a fast mode, allowing us to measure average lifetimes in below 1 min. DB measurements were carried out with a single detector and a 68Ge positron source by employing high momentum analysis. The various measurements show that NA is much more complex than anticipated and at least four different stages can be distinguished. The nature of these stages cannot be given with certainty, but a possible sequence includes vacancy diffusion to individual solute atoms, nucleation of solute clusters, Mg agglomeration to clusters and coarsening or ordering of such clusters. Positron lifetime measurements after more complex ageing treatments involving storage at 0 °C, 20 °C and 180 °C have also been carried out and help to understand the mechanisms involved.

Banhart, J.; Liu, M.; Yong, Y.; Liang, Z.; Chang, C. S. T.; Elsayed, M.; Lay, M. D. H.

2012-07-01

293

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

SciTech Connect

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

Airapetian, A.; Akopov, N.; Akopov, Z.; Aschenauer, E. C.; Augustyniak, W.; Jackson, H. E.; HERMES Collaboration (Physics); (Univ. Giessen); (Univ. of Michigan); (Yerevan Physics. Inst.); (DESY); (Andrzej Soltan Inst. for Nuclear Studies); (BNL)

2011-05-01

294

Measurement of the average lifetime of B hadrons produced in ppŻ collisions at ?s =1.8 TeV  

NASA Astrophysics Data System (ADS)

The average b-hadron lifetime has been measured using a high statistics sample of B-->J/? X decays recorded with the Collider Detector at Fermilab. The decay vertices of 5344 inclusive J/?-->?+?- candidates have been reconstructed using information from a silicon vertex detector. The measured B lifetime, which is the average over all b hadrons produced in ppŻ collisions at ?s =1.8 TeV weighted by their branching ratios into J/?, is 1.46+/-0.06(stat)+/-0.06(syst) ps.

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

1993-11-01

295

Measurement of the B meson Lifetimes with the Collider Detector at Fermilab  

SciTech Connect

The lifetimes of the B{sup -}, B{sup 0} and B{sub s}{sup 0} mesons are measured using partially reconstructed semileptonic decays. Following semileptonic decay processes and their charge conjugates are used for this analysis: B{sup -}/B{sup 0} {yields} {ell}{sup -}{nu}D{sup 0}X; B{sup -}/B{sup 0} {yields} {ell}{sup -}{nu}D*{sup +}X; B{sub s}{sup 0} {yields} {ell}{sup -}{nu}D{sub s}{sup +}x, where {ell}{sup -} denotes either a muon or electron. The data are collected during 2002-2004 by the 8 GeV single lepton triggers in CDF Run II at the Fermilab Tevatron Collider. Corresponding integrated luminosity is about 260 and 360 pb{sup -1} used for the B{sup -}/B{sup 0} and B{sub s}{sup 0} lifetime analyses, respectively. With the single lepton triggers, events which contain a muon or electron with a transverse momentum greater than 8 GeV/c are selected. For these lepton candidates, further lepton identification cuts are applied to improve purity of the B semileptonic decay signal. After the lepton selection, three types of charm mesons associated with the lepton candidates are reconstructed. Following exclusive decay modes are used for the charm meson reconstruction: D{sup 0} {yields} K{sup -}{pi}{sup +}; D*{sup +} {yields} D{sup 0}{pi}{sub s}{sup +}, followed by D{sup 0} {yields} K{sup -}{pi}{sup +}; D{sub s}{sup +} {yields} {phi}{pi}{sup +}, followed by {phi} {yields} K{sup +}K{sup -}. Here {pi}{sub s}{sup +} denotes a slow pion from D*{sup +} decay. Species of the reconstructed charm meson identify the parent B meson species. However in the B{sup -}/B{sup 0} semileptonic decays, both mesons decay into the identical lepton + D{sup 0} final state. To solve this mixture of the B components in the D{sup 0} sample, they adopt the following method: First among the inclusive D{sup 0} sample, they look for the D*{sup +} {yields} D{sup 0} {pi}{sub s}{sup +} signal. The inclusive D{sup 0} sample is then split into the two samples of D{sup 0} mesons which are from the D*{sup +} meson and not from D*{sup +}. They use the fact that D*{sup +} sample is dominated by the B{sup 0} component, and the D{sup 0} sample after excluding the D*{sup +} events is dominated by the B{sup -} component. Fraction of remaining mixture of B{sup -}/B{sup 0} components in each sample is estimated using a Monte Carlo simulation. From the lepton + charm meson pairs, they measure the B meson decay lengths to extract the lifetimes. Since the B meson momentum, necessary to calculate the B meson decay time, is not fully reconstructed in semileptonic decays, the missing momentum is corrected using a Monte Carlo simulation during lifetime fits. Also, contributions of various kinds of backgrounds are considered and subtracted. As a result of the fit, the B meson lifetimes are measured to be c{tau}(B{sup -}) = 495.6 {+-} 8.6 {sub -12.8}{sup +13.3} {micro}m; c{tau}(B{sup 0}) = 441.5 {+-} 10.9 {+-} 17.0 {micro}m; c{tau}(B{sub s}{sup 0}) = 414.0 {+-} 16.6 {sub -13.8}{sup +15.6} {micro}m or {tau}(B{sup 0}) = 1.653 {+-} 0.029 {sub -0.031}{sup +0.033} ps; {tau}(B{sup 0}) = 1.473 {+-} 0.036 {+-} 0.054 ps; {tau}(B{sub s}{sup 0}) = 1.381 {+-} 0.055 {sub -0.046}{sup +0.052} ps, and the lifetime ratios to be {tau}(B{sup 0})/{tau}(B{sup 0}) = 1.123 {+-} 0.040 {sub -0.039}{sup +0.041}; {tau}(B{sub s}{sup 0})/{tau}(B{sup 0}) = 0.938 {+-} 0.044 {sub -0.046}{sup +0.049} where the first uncertainty is statistical and the second is systematic.

Uozumi, Satoru; /Tsukuba U.

2006-01-01

296

Precision measurement of the mass and lifetime of the $\\Xi_b^0$ baryon  

E-print Network

Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 $\\Xi_b^0\\to\\Xi_c^+\\pi^-$, $\\Xi_c^+\\to pK^-\\pi^+$ signal decays are reconstructed. From this sample, the first measurement of the $\\Xi_b^0$ baryon lifetime is made, relative to that of the $\\Lambda_b^0$ baryon. The mass differences $M(\\Xi_b^0)-M(\\Lambda_b^0)$ and $M(\\Xi_c^+)-M(\\Lambda_c^+)$ are also measured with precision more than four times better than the current world averages. The resulting values are $\\frac{\\tau_{\\Xi_b^0}}{\\tau_{\\Lambda_b^0}} = 1.006\\pm0.018\\pm0.010$, $M(\\Xi_b^0) - M(\\Lambda_b^0) = 172.44\\pm0.39\\pm0.17 MeV/c^2$, $M(\\Xi_c^+) - M(\\Lambda_c^+) = 181.51\\pm0.14\\pm0.10 MeV/c^2$, where the first uncertainty is statistical and the second is systematic. The relative rate of $\\Xi_b^0$ to $\\Lambda_b^0$ baryon production is measured to be $\\frac{f_{\\Xi_b^0}}{f_{\\Lambda_b^0}}\\frac{{\\cal{B}}(\\Xi_b^0\\to\\Xi_c^+\\pi^-)}{{\\cal{B}}(\\Lam...

Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Balagura, Vladislav; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjřrnstad, Pĺl Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; van den Brand, Johannes; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Busetto, Giovanni; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carranza-Mejia, Hector; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gavrilov, Gennadii; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Giani', Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gordon, Hamish; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury

2014-01-01

297

Effective lifetime measurements in the Bs0?K+K-, B0?K+?- and Bs0??+K- decays  

NASA Astrophysics Data System (ADS)

Measurements of the effective lifetimes in the Bs0?K+K-, B0?K+?- and Bs0??+K- decays are presented using 1.0 fb of pp collision data collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. The analysis uses a data-driven approach to correct for the decay time acceptance. The measured effective lifetimes are ?Bs0?K+K-=1.407ą0.016 (stat)ą0.007 (syst) ps, ?B0?K+?-=1.524ą0.011 (stat)ą0.004 (syst) ps, ?Bs0??+K-=1.60ą0.06 (stat)ą0.01 (syst) ps. This is the most precise determination to date of the effective lifetime in the Bs0?K+K- decay and provides constraints on contributions from physics beyond the Standard Model to the Bs0 mixing phase and the width difference ??s.

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

2014-09-01

298

Measurement of the Lifetime of the Bs0 Meson Using the Exclusive Decay Mode Bs0 --> J/? ?  

NASA Astrophysics Data System (ADS)

The lifetime of the B0s meson is measured using the exclusive decay mode B0s-->J/? ?, where J/?-->?+?- and ?-->K+K-. The data sample consists of 110 pb-1 of ppŻ collisions at s = 1.8 TeV, collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995. We find 58+/-12 signal events, and the B0s meson lifetime is determined to be ?B0s = 1.34+0.23-0.19\\(stat\\)+/-0.05\\(syst\\) ps. This result is consistent with previous measurements of the B0s, B+, and B0d meson lifetimes and with theoretical predictions.

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

1996-09-01

299

QSO Lifetimes  

E-print Network

The QSO lifetime t_Q is one of the most fundamental quantities for understanding black hole and QSO evolution, yet it remains uncertain by several orders of magnitude. If t_Q is long, then only a small fraction of galaxies went through a luminous QSO phase. In contrast, a short lifetime would require most galaxies today to have undergone a QSO phase in their youth. The current best estimates or constraints on t_Q from black hole demographics and the radiative properties of QSOs vary from at least 10^6 to 10^8 years. This broad range still allows both possibilities: that QSOs were either a rare or a common stage of galaxy evolution. These constraints also do not rule out the possibility that QSO activity is episodic, with individual active periods much shorter than the total active lifetime. In the next few years a variety of additional observational constraints on the lifetimes of QSOs will become available, including clustering measurements and the proximity effect. These new constraints can potentially determine t_Q to within a factor of 3 and therefore answer one of the most fundamental questions in black hole evolution: Do they shine as they grow? This precision will also test the viability of our current model for accretion physics, specifically the radiative efficiency and need for super-Eddington luminosities to explain the black hole population.

Paul Martini

2003-04-01

300

Comparison of Minority Carrier Lifetime Measurements in Superstrate and Substrate CdTe PV Devices: Preprint  

SciTech Connect

We discuss typical and alternative procedures to analyze time-resolved photoluminescence (TRPL) measurements of minority carrier lifetime (MCL) with the hope of enhancing our understanding of how this technique may be used to better analyze CdTe photovoltaic (PV) device functionality. Historically, TRPL measurements of the fast recombination rate (t1) have provided insightful correlation with broad device functionality. However, we have more recently found that t1 does not correlate as well with smaller changes in device performance, nor does it correlate well with performance differences observed between superstrate and substrate CdTe PV devices. This study presents TRPL data for both superstrate and substrate CdTe devices where both t1 and the slower TRPL decay (t2) are analyzed. The study shows that changes in performance expected from small changes in device processing may correlate better with t2. Numerical modeling further suggests that, for devices that are expected to have similar drift field in the depletion region, effects of changes in bulk MCL and interface recombination should be more pronounced in t2. Although this technique may provide future guidance to improving CdS/CdTe device performance, it is often difficult to extract statistically precise values for t2, and therefore t2 data may demonstrate significant scatter when correlated with performance parameters.

Gessert, T. A.; Dhere, R. G.; Duenow, J. N.; Kuciauskas, D.; Kanevce, A.; Bergeson, J. D.

2011-07-01

301

Measurement of the Excited State Lifetime of a Cooper-Pair Box  

NASA Astrophysics Data System (ADS)

We have used a radio frequency superconducting single electron transistor (rf-SET) biased around the double Josephson quasiparticle peak to measure the lifetime T1 of the excited state of an Al/AlOx/Al Cooper-pair box (CPB) qubit. The CPB had a charging energy EC/kB = 0.78 K and a maximum Josephson coupling energy EJ/kB = 0.70 K and all measurements were made at about 40 mK. T1 was found by sending a pulse of microwaves to the gate of the CPB and then using the rf-SET to observe the decay rate of the charge signal on the CPB. Near the degeneracy point of the CPB, we observed T1 of approximately 100 ns, which was near the limit of the rf-SET bandwidth. As we move away from the degeneracy point, T1 varies, reaching a maximum of approximately 400 ns. We examine whether these changes in T1 are commensurate with the quantum noise spectral density from the rf-SET.

Yoon, Youngnoh; Palmer, B. S.; Wellstood, F. C.; Schneiderman, J. F.; Echternach, P. M.

2007-03-01

302

Optimization of ERK Activity Biosensors for both Ratiometric and Lifetime FRET Measurements  

PubMed Central

Among biosensors, genetically-encoded FRET-based biosensors are widely used to localize and measure enzymatic activities. Kinases activities are of particular interest as their spatiotemporal regulation has become crucial for the deep understanding of cell fate decisions. This is especially the case for ERK, whose activity is a key node in signal transduction pathways and can direct the cell into various processes. There is a constant need for better tools to analyze kinases in vivo, and to detect even the slightest variations of their activities. Here we report the optimization of the previous ERK activity reporters, EKAR and EKAREV. Those tools are constituted by two fluorophores adapted for FRET experiments, which are flanking a specific substrate of ERK, and a domain able to recognize and bind this substrate when phosphorylated. The latter phosphorylation allows a conformational change of the biosensor and thus a FRET signal. We improved those biosensors with modifications of: (i) fluorophores and (ii) linkers between substrate and binding domain, resulting in new versions that exhibit broader dynamic ranges upon EGF stimulation when FRET experiments are carried out by fluorescence lifetime and ratiometric measurements. Herein, we characterize those new biosensors and discuss their observed differences that depend on their fluorescence properties. PMID:24434874

Vandame, Pauline; Spriet, Corentin; Riquet, Franck; Trinel, Dave; Cailliau-Maggio, Katia; Bodart, Jean-François

2014-01-01

303

Histamine H1 receptors in schizophrenic patients measured by positron emission tomography.  

PubMed

Increasing evidence has shown that the histaminergic neuron system is implicated in the pathophysiology of schizophrenia. The aim of this study was to compare the distribution of histamine H1 receptors between schizophrenics and normal human subjects in vivo using positron emission tomography (PET). H1 receptor binding was measured in 10 normal subjects and 10 medicated schizophrenic patients by PET and [11C] doxepin, a radioligand for the H1 receptor. The binding potential (BP=Bmax/K(D)) of [11C] doxepin for available brain H1 receptors was calculated by a graphical analysis on voxel-by-voxel basis and compared between schizophrenics and normal subjects using the regions of interest (ROIs) and the statistical parametrical mapping (SPM99). BP values for H1 receptors in the frontal and prefrontal cortices and the cingulate gyrus were significantly lower among the schizophrenic patients than among the control subjects. On the contrary, there were no areas of the brain where H1 receptors were significantly higher among the schizophrenic patients than the control subjects. The results of our study suggest that the central histaminergic neuron system could be involved in the pathophysiology of schizophrenia, although further studies are needed to confirm this hypothesis. PMID:15695063

Iwabuchi, Kentaro; Ito, Chihiro; Tashiro, Manabu; Kato, Motohisa; Kano, Michiko; Itoh, Masatoshi; Iwata, Ren; Matsuoka, Hiroo; Sato, Mitsumoto; Yanai, Kazuhiko

2005-03-01

304

Non-contacting measurements of photocarrier lifetimes in bulk-and polycrystalline thin-film Si photoconductive devices  

E-print Network

-Si photoconductive device, and to polysilicon thin-film photoconductors deposited on oxidized Si substratesNon-contacting measurements of photocarrier lifetimes in bulk- and polycrystalline thin-film Si thin-film devices. In the case of the bulk-Si device, the results of photothermal radiometry were

Mandelis, Andreas

305

Measuring the Stock of Human Capital for Comparative Analysis: An Application of the Lifetime Income Approach to Selected Countries  

Microsoft Academic Search

This paper summarizes the outcomes of the first phase of the OECD human capital project. In so doing, it shows the feasibility of applying the lifetime income approach to measuring human capital for comparative analysis, both across countries and over time. It also highlights the feasibility of applying the methodology to the categorical data (i.e. by 5-year or 10-year age

Gang Liu

2011-01-01

306

Magnetic dipole transition rates from measured lifetimes of levels of Be-like and B-like argon ions  

E-print Network

The lifetimes of the 1s(2)2s2p P-3(2) level of Ar XV and 1s(2)2s(2)2p P-2(3/2) of Ar XIV have been measured using metastable Ar14+ and Ar13+ ions produced by an electron cyclotron resonance ion source, which were subsequently separately captured...

Moehs, D. P.; Church, David A.

1998-01-01

307

Measurement of the [bar over B][0 over s] Meson Lifetime in D[+ over s]?[superscript ?] Decays  

E-print Network

We present a measurement of the ratio of the [bar over B][0 over s] meson lifetime, in the flavor-specific decay to D[+ over s]?[superscript ?], to that of the [bar over B][superscript 0] meson. The pp collision data used ...

Aaij, R.

308

Precision Measurement of the Mass and Lifetime of the ?b0 Baryon  

NASA Astrophysics Data System (ADS)

Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb-1 collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 ?b0??c+?-, ?c+?pK-?+ signal decays are reconstructed. From this sample, the first measurement of the ?b0 baryon lifetime is made, relative to that of the ?b0 baryon. The mass differences M(?b0)-M(?b0) and M(?c+)-M(?c+) are also measured with precision more than 4 times better than the current world averages. The resulting values are ?/?b0??b0=1.006ą0.018ą0.010,M(?b0)-M(?b0)=172.44ą0.39ą0.17 MeV /c2,M(?c+)-M(?c+)=181.51ą0.14ą0.10 MeV /c2,where the first uncertainty is statistical and the second is systematic. The relative rate of ?b0 to ?b0 baryon production is measured to be f/?b0f?b0B(?/b0??c+?-)B(?b0??c+?-)B(?/c+?pK-?+)B(?c+?pK-?+)=(1.88ą0.04ą0.03)×10-2,where the first factor is the ratio of fragmentation fractions, b??b0 relative to b??b0. Relative production rates as functions of transverse momentum and pseudorapidity are also presented.

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

2014-07-01

309

Precision measurement of the mass and lifetime of the $?_b^0$ baryon  

E-print Network

Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 $\\Xi_b^0\\to\\Xi_c^+\\pi^-$, $\\Xi_c^+\\to pK^-\\pi^+$ signal decays are reconstructed. From this sample, the first measurement of the $\\Xi_b^0$ baryon lifetime is made, relative to that of the $\\Lambda_b^0$ baryon. The mass differences $M(\\Xi_b^0)-M(\\Lambda_b^0)$ and $M(\\Xi_c^+)-M(\\Lambda_c^+)$ are also measured with precision more than four times better than the current world averages. The resulting values are $\\frac{\\tau_{\\Xi_b^0}}{\\tau_{\\Lambda_b^0}} = 1.006\\pm0.018\\pm0.010$, $M(\\Xi_b^0) - M(\\Lambda_b^0) = 172.44\\pm0.39\\pm0.17 MeV/c^2$, $M(\\Xi_c^+) - M(\\Lambda_c^+) = 181.51\\pm0.14\\pm0.10 MeV/c^2$, where the first uncertainty is statistical and the second is systematic. The relative rate of $\\Xi_b^0$ to $\\Lambda_b^0$ baryon production is measured to be $\\frac{f_{\\Xi_b^0}}{f_{\\Lambda_b^0}}\\frac{{\\cal{B}}(\\Xi_b^0\\to\\Xi_c^+\\pi^-)}{{\\cal{B}}(\\Lambda_b^0\\to\\Lambda_c^+\\pi^-)}\\frac{{\\cal{B}}(\\Xi_c^+\\to pK^-\\pi^+)}{{\\cal{B}}(\\Lambda_c^+\\to pK^-\\pi^+)} = (1.88\\pm0.04\\pm0.03)\\times10^{-2}$, where the first factor is the ratio of fragmentation fractions, $b\\to\\Xi_b^0$ relative to $b\\to\\Lambda_b^0$. Relative production rates as functions of transverse momentum and pseudorapidity are also presented.

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

2014-05-28

310

High-spin lifetime measurements in the N=Z nucleus {sup 72}Kr  

SciTech Connect

High-spin states in the N=Z nucleus {sup 72}Kr have been populated in the {sup 40}Ca({sup 40}Ca, 2{alpha}){sup 72}Kr fusion-evaporation reaction at a beam energy of 165 MeV using the Gammasphere array for {gamma}-ray detection coupled to the Microball array for charged particle detection. The previously observed bands in {sup 72}Kr were extended to an excitation energy of {approx}24 MeV and angular momentum of 30({Dirac_h}/2{pi}). Using the Doppler shift attenuation method the lifetimes of high-spin states were measured for the first time. Excellent agreement between the results of calculations within the isovector mean field theory and experiment is observed both for rotational and deformation properties. No enhancement of quadrupole deformation expected in the presence of isoscalar t=0 np pairing is observed. Current data do not show any evidence for the existence of the isoscalar np pairing.

Andreoiu, C. [Department of Physics, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 3BX (United Kingdom); Svensson, C. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hyland, B.; Phillips, A. A.; Schumaker, M. A.; Valiente-Dobon, J. J. [Department of Physics, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Afanasjev, A. V. [Department of Physics and Astronomy, Mississippi State University, Starkville, Mississippi 39762 (United States); Austin, R. A. E. [McMaster University, Hamilton, Ontario, L8S 4K1 (Canada); Carpenter, M. P.; Freeman, S. J.; Greene, J.; Moore, F.; Mukherjee, G.; Seweryniak, D. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60436 (United States); Dashdorj, D. [North Carolina State University, Raleigh, Norht Carolina 27695 (United States); Goergen, A. [CEA Saclay, Daphnia/SphN, F-91191 Gif-sur-Yvette Cedex (France); Jenkins, D. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)] (and others)

2007-04-15

311

Volatility of organic molecular markers used for source apportionment analysis: measurements and implications for atmospheric lifetime.  

PubMed

Molecular markers are organic species used to define fingerprints for source apportionment of ambient fine particulate matter. Traditionally, these markers have been assumed to be stable in the atmosphere. This work investigates the gas-particle partitioning of eight organic species used as molecular markers in receptor models for biomass burning (levoglucosan), motor vehicles (5?-cholestane, n-hexacosane, n-triacontane, 1,2-benz[a]anthracene, coronene), and meat cooking (cholesterol, oleic acid). Experiments were conducted using a thermodenuder to measure the evaporation of single component particles. The data were analyzed using the integrated volume method to determine saturation concentrations and enthalpies of vaporization for each compound. The results indicate that appreciable quantities (>10%) of most of these markers exist in the gas phase under typical atmospheric conditions. Therefore, these species should be considered semivolatile. Predictions from a chemical kinetics model indicate that gas-particle partitioning has important effects on the atmospheric lifetime of these species. The atmospheric decay of semivolatile compounds proceeds much more rapidly than nonvolatile compounds because gas-phase oxidation induces evaporation of particle-phase material. Therefore, both gas-particle partitioning and chemical reactions need to be accounted for when semivolatile molecular markers are used for source apportionment studies. PMID:23013599

May, Andrew A; Saleh, Rawad; Hennigan, Christopher J; Donahue, Neil M; Robinson, Allen L

2012-11-20

312

Positron trapping at grain boundaries  

SciTech Connect

The standard positron trapping model has often been applied, as a simple approximation, to the interpretation of positron lifetime spectra in situations of diffusion-controlled trapping. This paper shows that this approximation is not sufficiently accurate, and presents a model based on the correct solution of the diffusion equation, in the version appropriate for studying positron trapping at grain boundaries. The model is used for the analysis of new experimental data on positron lifetime spectra in a fine-grained Al-Ca-Zn alloy. Previous results on similar systems are also discussed and reinterpreted. The analysis yields effective diffusion coefficients not far from the values known for the base metals of the alloys.

Dupasquier, A. (Dipartimento di Fisica del Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)); Romero, R.; Somoza, A. (Instituto de Fisica de Materiales Tandil, Facultad de Ciencias Exactas, Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, 7000 Tandil (Argentina))

1993-10-01

313

Picosecond planar laser-induced fluorescence measurements of OH A 2 ( 2) lifetime and energy transfer in atmospheric pressure flames  

NASA Astrophysics Data System (ADS)

A picosecond, excimer-Raman laser (268 nm, 400 ps FWHM) was used for laser sheet excitation of OH in the (2, 0) band. The fluorescence was detected with a fast-gated, intensified camera (400-ps gate width). The effective collisional lifetime of the spectrally integrated fluorescence was measured in two dimensions by shifting the intensifier gate across the decay curve. The average lifetime is 2.0 ns for a stoichiometric methane air flame with spatial variations of 10 . Shorter collisional lifetimes were measured for rich flame conditions that are due to a higher number density of the quenchers. Vibrational energy transfer (VET) was observed in premixed methane air and methane oxygen flames by putting the fast-gated camera behind a spectrometer. The spectrum of the methane air flame shows strong VET in contrast with the methane oxygen flame. This is because N 2 is a weak electronic quencher but a strong VET agent. By fitting the measured time dependence of the different vibrational populations ( 2, 1, 0) to a four-level model, rate constants for quenching and VET were determined. For the lower states ( 0, 1) our results are in good agreement with literature values. For a prediction of a spectrally integrated, collisional lifetime in a known collisional environment it is important to consider not only the quenching but also the amount of energy transfer in the excited state as well as the spectral detection sensitivity.

Bormann, Frank C.; Nielsen, Tim; Burrows, Michael; Andresen, Peter

1997-08-01

314

Measurement of the BŻs0 Effective Lifetime in the J/?f0(980) Final State  

NASA Astrophysics Data System (ADS)

The effective lifetime of the BŻs0 meson in the decay mode BŻs0?J/?f0(980) is measured using 1.0fb-1 of data collected in pp collisions at s=7TeV with the LHCb detector. The result is 1.700ą0.040ą0.026ps, where the first uncertainty is statistical and the second systematic. As the final state is CP-odd, and CP violation in this mode is measured to be small, the lifetime measurement can be translated into a measurement of the decay width of the heavy BŻs0 mass eigenstate, ?H=0.588ą0.014ą0.009ps-1.

Aaij, R.; Abellan Beteta, C.; Adametz, A.; 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.; Amhis, Y.; Anderlini, L.; Anderson, J.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Bachmann, S.; Back, J. J.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bates, A.; Bauer, C.; Bauer, Th.; Bay, A.; Beddow, J.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Benayoun, M.; Bencivenni, G.; Benson, S.; Benton, J.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjřrnstad, P. M.; Blake, T.; Blanc, F.; Blanks, C.; Blouw, J.; Blusk, S.; Bobrov, A.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Büchler-Germann, A.; Burducea, I.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cattaneo, M.; Cauet, Ch.; 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.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; David, P.; David, P. N. Y.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Degaudenzi, H.; Del Buono, L.; Deplano, C.; Derkach, D.; Deschamps, O.; Dettori, F.; Dickens, J.; Dijkstra, H.; Diniz Batista, P.; Domingo Bonal, F.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisele, F.; Eisenhardt, S.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Elsby, D.; Esperante Pereira, D.; Falabella, A.; Färber, C.; Fardell, G.; Farinelli, C.; Farry, S.; Fave, V.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furcas, S.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garnier, J.-C.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gibson, V.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Harrison, P. F.; Hartmann, T.; He, J.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Hicks, E.; Hoballah, M.; Hopchev, P.; Hulsbergen, W.; Hunt, P.; Huse, T.; Huston, R. S.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Ilten, P.; Imong, J.; Jacobsson, R.; Jaeger, A.; Jahjah Hussein, M.; Jans, E.; Jansen, F.; Jaton, P.; Jean-Marie, B.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Jost, B.; Kaballo, M.; Kandybei, S.; Karacson, M.; Karbach, T. M.; Keaveney, J.; Kenyon, I. R.; Kerzel, U.; Ketel, T.; Keune, A.; Khanji, B.; Kim, Y. M.; Knecht, M.; 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.; Lefčvre, R.; Leflat, A.; Lefrançois, J.; Leroy, O.; Lesiak, T.; Li, L.; Li, Y.; Li Gioi, L.; Lieng, M.; Liles, M.; Lindner, R.; Linn, C.; Liu, B.; Liu, G.; von Loeben, J.; Lopes, J. H.; Lopez Asamar, E.; Lopez-March, N.; Lu, H.; Luisier, J.; Mac Raighne, A.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Magnin, J.; Malde, S.; Mamunur, R. M. D.; Manca, G.; Mancinelli, G.; Mangiafave, N.; Marconi, U.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Martin, L.; Martín Sánchez, A.; Martinelli, M.; Martinez Santos, D.; Massafferri, A.

2012-10-01

315

Measurement of the BŻ(s)(0) effective lifetime in the J/?f0(980) final state.  

PubMed

The effective lifetime of the B Ż(s)(0) meson in the decay mode BŻ(s)(0)?J/?f(0)(980) is measured using 1.0 fb(-1) of data collected in pp collisions at ?s=7 TeV with the LHCb detector. The result is 1.700ą0.040ą0.026 ps, where the first uncertainty is statistical and the second systematic. As the final state is CP-odd, and CP violation in this mode is measured to be small, the lifetime measurement can be translated into a measurement of the decay width of the heavy BŻ(s)(0) mass eigenstate, ?(H)=0.588ą0.014ą0.009 ps(-1). PMID:23102295

Aaij, R; Abellan Beteta, C; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderlini, L; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjřrnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; 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; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hoballah, M; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; 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; Lefčvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li, Y; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Mac Raighne, A; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Mazurov, A; McCarthy, J; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A

2012-10-12

316

Development of a high resolution beta camera for a direct measurement of positron distribution on brain surface  

SciTech Connect

We have developed and tested a high resolution beta camera for a direct measurement of positron distribution on brain surface of animals. The beta camera consists of a thin CaF{sub 2}(Eu) scintillator, a tapered fiber optics plate (taper fiber) and a position sensitive photomultiplier tube (PSPMT). The taper fiber is the key component of the camera. We have developed two types of beta cameras. One is 20mm diameter field of view camera for imaging brain surface of cats. The other is 10mm diameter camera for that of rats. Spatial resolutions of beta camera for cats and rats were 0.8mm FWHM and 0.5mm FWHM, respectively. We confirmed that developed beta cameras may overcome the limitation of the spatial resolution of the positron emission tomography (PET).

Yamamoto, S. [Kobe City College of Technology, Nishi-ku (Japan); Seki, C.; Kashikura, K. [Akita Lab. (Japan)] [and others

1996-12-31

317

Reduced Cannabinoid CB1 Receptor Binding in Alcohol Dependence Measured with Positron Emission Tomographys  

PubMed Central

Brain cannabinoid CB1 receptors contribute to alcohol-related behaviors in experimental animals, but their potential role in humans with alcohol dependence is poorly understood. We measured CB1 receptors in alcohol dependent patients in early and protracted abstinence, and in comparison with control subjects without alcohol use disorders, using positron emission tomography (PET) and [18F]FMPEP-d2, a radioligand for CB1 receptors. We scanned 18 male inpatients with alcohol dependence twice, within 3–7 days of admission from ongoing drinking, and after 2–4 weeks of supervised abstinence. Imaging data were compared with those from 19 age-matched healthy male control subjects. Data were also analyzed for potential influence of a common functional variation (rs2023239) in the CB1 receptor gene (CNR1) that may moderate CB1 receptor density. On the first scan, CB1 receptor binding was 20–30% lower in patients with alcohol dependence than in control subjects in all brain regions and was negatively correlated with years of alcohol abuse. After 2–4 weeks of abstinence, CB1 receptor binding remained similarly reduced in these patients. Irrespective of diagnostic status, C allele carriers at rs2023239 had higher CB1 receptor binding compared to non-carriers. Alcohol dependence is associated with a widespread reduction of cannabinoid CB1 receptor binding in the human brain and this reduction persists at least 2–4 weeks into abstinence. The correlation of reduced binding with years of alcohol abuse suggests an involvement of CB1 receptors in alcohol dependence in humans. PMID:22776901

Hirvonen, Jussi; Zanotti-Fregonara, Paolo; Umhau, John C.; George, David T.; Rallis-Frutos, Denise; Lyoo, Chul Hyoung; Li, Cheng-Ta; Hines, Christina S.; Sun, Hui; Terry, Garth E.; Morse, Cheryl; Zoghbi, Sami S.; Pike, Victor W.; Innis, Robert B.; Heilig, Markus

2012-01-01

318

CFCl3 (CFC-11): UV Absorption Spectrum Temperature Dependence Measurements and the Impact on Atmospheric Lifetime Uncertainty  

NASA Astrophysics Data System (ADS)

CFCl3 (CFC-11) is both a major ozone-depleting substance and a potent greenhouse gas that is removed primarily via stratospheric UV photolysis. Uncertainty in the temperature dependence of its UV absorption spectrum is a significant contributing factor to the overall uncertainty in its global lifetime and, thus, model calculations of stratospheric ozone recovery and climate change. In this work, the CFC-11 UV absorption spectrum was measured over a range of wavelength (184.95-230 nm) and temperature (216-296 K). We report a spectrum temperature dependence that is less than currently recommended for use in atmospheric models. The impact on its atmospheric lifetime was quantified using the NASA Goddard Space Flight Center 2-D coupled chemistry-radiation-dynamics model and the spectrum parameterization developed in this work. The modeled global annually averaged lifetime was 58.1 × 0.7 years (2? uncertainty due solely to the spectrum uncertainty). The lifetime is slightly reduced and the uncertainty significantly reduced from that obtained using current UV spectrum recommendations. CFCl 3 (CFC-11) 2-D model results: Left: Global annually averaged loss rate coefficient (local lifetime) and photolysis and reaction contributions (see legend). Middle: Molecular loss rate and uncertainty limits; the slow and fast profiles were calculated using the 2? uncertainty estimates in the CFC-11 UV absorption spectrum from this work. Right: CFC-11 concentration profile. CFC-11 loss process contribution to the overall local lifetime uncertainty (2?) calculated using the 2-D model (see text). Left: Results obtained from this work. Right: Results obtained using model input from Sander et al. [2011] and updates in SPARC [2013].

McGillen, M.; Fleming, E. L.; Jackman, C. H.; Burkholder, J. B.

2013-12-01

319

Analysis of the photo voltage decay /PVD/ method for measuring minority carrier lifetimes in P-N junction solar cells  

NASA Technical Reports Server (NTRS)

The photo voltage decay (PVD) method for the measurement of minority carrier lifetimes in P-N junction solar cells with cell thickness comparable to or even less than the minority carrier diffusion length is examined. The method involves the generation of free carriers in the quasi-neutral bulk material by flashes of light and the monitoring of the subsequent decay of the induced open-circuit voltages as the carriers recombine, which is dependent on minority carrier recombination lifetime. It is shown that the voltage versus time curve for an ordinary solar cell (N(+)-P junction) is proportional to the inverse minority carrier lifetime plus a factor expressing the ratio of diffusion length to cell thickness. In the case of an ideal back-surface-field cell (N(+)-P-P(+) junction) however, the slope is directly proportional to the inverse minority carrier lifetime. It is noted that since most BSF cells are not ideal, possessing a sizable back surface recombination velocity, the PVD measurements must be treated with caution and supplemented with other nonstationary methods.

Von Roos, O.

1981-01-01

320

Measurement of the B0s lifetime in the exclusive decay channel B0s-->J/psiphi.  

PubMed

Using the exclusive decay B0s-->J/psi(mu+mu-)phi(K+K-), we report the most precise single measurement of the B0s lifetime. The data sample corresponds to an integrated luminosity of approximately 220 pb(-1) collected with the D0 detector at the Fermilab Tevatron Collider in 2002-2004. We reconstruct 337 signal candidates, from which we extract the B0s lifetime, tau(B0s)=1.444(+0.098)(-0.090)(stat)+/-0.020(sys) ps. We also report a measurement for the lifetime of the B0 meson using the exclusive decay B0-->J/psi(mu+mu-)K*0(892)(K+pi-). We reconstruct 1370 signal candidates, obtaining tau(B0)=1.473(+0.052)(-0.050)(stat)+/-0.023(sys) ps, and the ratio of lifetimes, tau(B0s)/tau(B0)=0.980(+0.076)(-0.071)(stat)+/-0.003(sys). PMID:15783550

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, D L; Adams, M; Adams, T; Agelou, M; Agram, J-L; Ahmed, S N; Ahn, S H; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Anderson, S; Andrieu, B; Arnoud, Y; Askew, A; Asman, B; Atramentov, O; Autermann, C; Avila, C; Babukhadia, L; Bacon, T C; Badaud, F; Baden, A; Baffioni, S; Baldin, B; Balm, P W; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beauceron, S; Beaudette, F; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Besson, A; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Bhattacharjee, M; Binder, M; Bischoff, A; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Boehnlein, A; Boeriu, O; Bolton, T A; Bonamy, P; Borcherding, F; Borissov, G; Bos, K; Bose, T; Boswell, C; Brandt, A; Briskin, G; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Burdin, S; Burnett, T H; Busato, E; Butler, J M; Bystricky, J; Canelli, F; Carvalho, W; Casey, B C K; Casey, D; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Chevalier, L; Cho, D K; Choi, S; Chopra, S; Christiansen, T; Christofek, L; Claes, D; Clark, A R; Clément, B; Clément, C; Coadou, Y; Colling, D J; Coney, L; Connolly, B; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Coss, J; Cothenet, A; Cousinou, M-C; Crépé-Renaudin, S; Cristetiu, M; Cummings, M A C; Cutts, D; da Motta, H; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Dean, S; Del Signore, K; Déliot, F; Delsart, P A; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dong, H; Doulas, S; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Eltzroth, J T; Elvira, V D; Eno, S; Ermolov, P; Eroshin, O V; Estrada, J; Evans, D; Evans, H; Evdokimov, A; Evdokimov, V N; Fast, J; Fatakia, S N; Fein, D; Feligioni, L; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleuret, F; Fortner, M; Fox, H; Freeman, W; Fu, S; Fuess, S; Galea, C F; Gallas, E; Galyaev, E; Gao, M; Garcia, C; Garcia-Bellido, A; Gardner, J; Gavrilov, V; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Y; Geurkov, G; Ginther, G; Goldmann, K; Golling, T; Gómez, B; Gounder, K; Goussiou, A; Graham, G; Grannis, P D; Greder, S; Green, J A; Greenlee, H; Greenwood, Z D; Gregores, E M; Grinstein, S; Gris, Ph; Grivaz, J-F; Groer, L; Grünendahl, S; Grünewald, M W; Gu, W; Gurzhiev, S N; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haggerty, H; Hagopian, S; Hall, I; Hall, R E; Han, C; Han, L; Hanagaki, K; Hanlet, P; Harder, K; Harrington, R; Hauptman, J M; Hauser, R; Hays, C; Hays, J; Hebbeker, T; Hebert, C; 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; Hou, S; Houben, P; Hu, Y; Huang, J; Huang, Y; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jenkins, A; Jesik, R; Jiang, Y; Johns, K; Johnson, M; Johnson, P; Jonckheere, A; Jonsson, P; Jöstlein, H; Juste, A; Kado, M M; Käfer, D; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Karmanov, D; Kasper, J; Kau, D; Ke, Z; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A; Kharzheev, Y M; Kim, K H; Klima, B; Klute, M; Kohli, J M; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Kotwal, A V; Koubarovsky, A; Kouznetsov, O; Kozelov, A V; Kozminski, J; Krane, J; Krishnaswamy, M R; Krzywdzinski, S; Kubantsev, M; Kuleshov, S; Kulik, Y; Kunori, S; Kupco, A; Kurca, T; Kuznetsov, V E; Lager, S; Lahrichi, N; Landsberg, G; Lazoflores, J; Le Bihan, A-C; Lebrun, P; Lee, S W; Lee, W M; Leflat, A; Leggett, C; Lehner, F; Leonidopoulos, C; Lewis, P; Li, J; Li, Q Z; Li, X; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Lobo, L; Lobodenko, A; Lokajicek, M; Lounis, A; Lu, J; Lubatti, H J; Lucotte, A; Lueking, L; Luo, C; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magerkurth, A; Magnan, A-M; Maity, M; Makovec, N; Mal, P K; Malik, S; Malyshev, V L; Manankov, V; Mao, H S; Maravin, Y; Marshall, T; Martens, M; Martin, M I; Mattingly, S E K; Mayorov, A A; McCarthy, R; McCroskey, R; McMahon, T; Meder, D; Melanson, H L; Melnitchouk, A; Meng, X; Merkin, M; Merritt, K W; Meyer, A; Miao, C; Miettinen, H; Mihalcea, D; Mitrevski, J; Mokhov, N; Molina, J; Mondal, N K; Montgomery, H E; Moore, R W; Mostafa, M; Muanza, G S; Mulders, M; Mutaf, Y D; Nagy, E; Nang, F; Narain, M; Narasimham, V S; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Noeding, C

2005-02-01

321

Positron microscopy  

SciTech Connect

The negative work function property that some materials have for positrons make possible the development of positron reemission microscopy (PRM). Because of the low energies with which the positrons are emitted, some unique applications, such as the imaging of defects, can be made. The history of the concept of PRM, and its present state of development will be reviewed. The potential of positron microprobe techniques will be discussed also.

Hulett, L.D. Jr.; Xu, J.

1995-02-01

322

In vivo activity of bupropion at the human dopamine transporter as measured by positron emission tomography  

Microsoft Academic Search

BackgroundConverging lines of evidence are consistent with an inhibitory effect of the antidepressant and smoking-cessation aid bupropion on dopamine and norepinephrine reuptake, but the in vivo effects of the drug at the human dopamine transporter (DAT) have not been studied to date. This study employed positron emission tomography (PET) to assess the extent and duration of DAT receptor occupancy by

Susan M Learned-Coughlin; Mats Bergström; Irina Savitcheva; John Ascher; Virginia D Schmith; Bengt Lĺngstrom

2003-01-01

323

a New Plunger Device for Investigating the Effects of Deformation on Proton Emission Rates via Lifetime Measurements  

NASA Astrophysics Data System (ADS)

A new plunger device has been designed and built to measure the lifetimes of unbound states in exotic nuclei beyond the proton drip-line. The device is designed to work in both vacuum and dilute-gas environments made possible through the introduction of a lowvoltage piezoelectric motors. The differential plunger for unbound nuclear states, DPUNS, will be used in conjunction with the gas-filled separator RITU and the vacuum separator MARA at the accelerator laboratory of the University of Jyväskylä, Finland, to measure the lifetimes of excited states with low population cross-sections. This is achieved by eliminating the need for a carbon foil to isolate the helium gas of RITU from the beam line thus reducing the background from beam-foil reactions. The plunger will be used to address many key facets of nuclear structure physics with particular emphasis on the effect of deformation on proton emission rates.

Taylor, M. J.; Cullen, D. M.; Smith, A. J.; McFarlane, A.; Twist, V.; Procter, M. G.; Alharshan, G. A.; Braunroth, T.; Dewald, A.; Ellinger, E.; Fransen, C.; Butler, P. A.; Scheck, M.; Joss, D. T.; Saygi, B.; McPeake, C. G.; Grahn, T.; Greenlees, P. T.; Jakobsson, U.; Jones, P.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Nieminen, P.; Pakarinen, J.; Peura, P.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J.

2013-06-01

324

Method and apparatus for measuring minority carrier lifetimes and bulk diffusion length in P-N junction solar cells  

NASA Technical Reports Server (NTRS)

Carrier lifetimes and bulk diffusion length are qualitatively measured as a means for qualification of a P-N junction photovoltaic solar cell. High frequency (blue) monochromatic light pulses and low-frequency (red) monochromatic light pulses were alternately applied to the cell while it was irradiated by light from a solar simulator, and synchronously displaying the derivative of the output voltage of the cell on an oscilloscope. The output voltage is a measure of the lifetimes of the minority carriers (holes) in the diffused N layer and majority carriers (electrons) in the bulk P material, and of the diffusion length of the bulk silicon. By connecting a reference cell in this manner with a test cell to be tested in reverse parallel, the display of a test cell that matches the reference cell will be a substantially zero output.

Vonroos, O. H. (inventor)

1978-01-01

325

Time-resolved photoluminescence for self-calibrated injection-dependent minority carrier lifetime measurements in silicon  

NASA Astrophysics Data System (ADS)

Time-resolved photoluminescence (TRPL) was investigated on passivated silicon wafers under modulated square-wave laser illumination. It is shown that time-correlated single-photon counting can be used to record the transient signals on silicon wafers with doping levels commonly used for photovoltaic applications. This article reports the self calibrated evaluation of the injection-dependent effective minority carrier lifetime from the TRPL measurements. The method only requires knowing the doping level, the incident laser power, the reflection coefficient and the sample thickness. TRPL results were found to be in good agreement with photoconductance lifetime measurements. The effect of the surface recombination velocity on the generation of the PL signal was shown experimentally and discussed with PC1D calculations.

Parola, S.; Daanoune, M.; Kaminski-Cachopo, A.; Lemiti, M.; Blanc-Pélissier, D.

2015-01-01

326

Measurement of Electromagnetic Cross Sections in Heavy Ion Interations and Its Consequences for Luminosity Lifetimes in Ion Colliders  

SciTech Connect

The limitation of the luminosity lifetime in high energy heavy ion colliders like RHIC or LHC operating in ion mode is set by the very large cross section of beam - beam interactions. One of the dominant processes at relativistic energies is electron capture from pair production in the strong electromagnetic field provided by the high Z of the ions. The capture cross sections for Pb82+ interacting with a number targets have been measured using one of the high energy resolution 158 GeV/nucleon beams at CERN. The results, together with results on electromagnetic dissociation, are discussed in terms of beam lifetimes for RHIC and LHC using extrapolations of the measurements to the corresponding collider energies.

Datz, S.; Grafstroem, P.; Knudsen, H.; Krause, H.F.; Mikkelsen, U.; Scheidenberger, C.; Schuch, R.H.; Vane, C.R.; Vilakazi, Z.

1999-03-29

327

Alternative Size and Lifetime Measurements for High-Energy Heavy-Ion Collisions  

E-print Network

Two-Particle correlations based on the interference of identical particles has provided the chief means for determining the shape and lifetime of sources in relativistic heavy ion collisions. Here, Strong and Coulomb induced correlations are shown to provide equivalent information.

Scott Pratt; Silvio Petriconi

2003-06-16

328

Measurement of the lifetime difference in the B-s(0) system  

E-print Network

We present a study of the decay B-s(0)-> J/psi phi. We obtain the CP-odd fraction in the final state at time zero R-perpendicular to = 0.16 +/- 0.10 (stat) +/- 0.02(syst), the average lifetime of the (B-s(0), (B) over bar ...

Baringer, Philip S.; Bean, Alice; Christofek, L.; Coppage, Don; Gardner, J.; Hensel, Carsten; Jabeen, S.; Moulik, Tania; Wilson, Graham Wallace

2005-10-01

329

Steady-State and Frequency-Domain Lifetime Measurements of an Activated Molecular Imprinted Polymer Imprinted to Dipicolinic Acid  

Microsoft Academic Search

We recently demonstrated the synthesis and fluorescence activity associated with an optical detector incorporating a molecular imprinted polymer (MIP). Steady-state and time-resolved (lifetime) fluorescence measurements were used to characterize the binding activity associated with MIP microparticles imprinted to dipicolinic acid (DPA). DPA is a unique biomarker associated with the sporulation phase of endospore-forming bacteria. Vinylic monomers were polymerized in a

John Anderson; Jean Nelson; Charles Reynolds; Dave Ringelberg; Gary Tepper; Dmitry Pestov

2004-01-01

330

Measurement of the Inclusive B-Lifetime Using $\\\\rm {J\\/\\\\psi}$'s at the CDF Experiment  

Microsoft Academic Search

This dissertation describes the measurement of the average B hadron lifetime using a high statistics sample of B J\\/X decays produced in p{bar p} collisions at a center of mass energy of s = 1.8 TeV at the Fermilab Tevatron. The integrated luminosity of the sample is 10.1 pbš recorded with the Collider Detector at Fermilab (CDF). In this analysis

Hans-Joachim Wenzel

1993-01-01

331

Combined measurement of velocity and temperature distributions in oil based on the luminescent lifetimes of seeded particles  

NASA Astrophysics Data System (ADS)

The velocity field and temperature distribution in a fluid flow were measured simultaneously based on luminescence. PIV is useful for velocity measurement, and a measurement method based on the luminescent lifetime is appropriate for detecting the transient temperature field. However, there have been few reports on thermometry in the fluid flow by luminescence, whereas several studies have investigated surface temperature measurement. The europium complex (EuTTA) has been commonly used in temperature-sensitive 'paints' for several years and consequently has been examined in several papers. In the present study, particles doped with EuTTA, called temperature-sensitive particles (TSParticles), were prepared. The optical properties of the TSParticles were investigated. A TSParticle was found to be suitable for use with an optical sensor because its lifetime is very sensitive to temperature changes. The lifetime of the TSParticle was approximately 600 ľs at 20 °C in water and the intensity was also large enough to be detected by a CCD camera without any image intensifier, at an exposure time of less than 60 ľs. It was found that TSParticles could also be used for velocity measurement by means of the PIV technique. The temperature field was measured based on the decay ratio of the TSParticle images, and the velocity distribution in the same plane was also evaluated from these images by PIV. A demonstration was carried out in a thermal stratified silicone oil bath. The velocity and the transient temperature distribution of the oil flow were successfully measured. The spatial resolution of the temperature measurement in the demonstration was 60 ľm. The uncertainty of the temperature was 0.35 °C. The spatial resolution and the uncertainty of velocity measurement were 0.6 mm and 20 ľm s-1, respectively.

Someya, Satoshi; Yoshida, Satoshi; Li, Yanrong; Okamoto, Koji

2009-02-01

332

Brain metabolism in autism. Resting cerebral glucose utilization rates as measured with positron emission tomography  

SciTech Connect

The cerebral metabolic rate for glucose was studied in ten men (mean age = 26 years) with well-documented histories of infantile autism and in 15 age-matched normal male controls using positron emission tomography and (F-18) 2-fluoro-2-deoxy-D-glucose. Positron emission tomography was completed during rest, with reduced visual and auditory stimulation. While the autistic group as a whole showed significantly elevated glucose utilization in widespread regions of the brain, there was considerable overlap between the two groups. No brain region showed a reduced metabolic rate in the autistic group. Significantly more autistic, as compared with control, subjects showed extreme relative metabolic rates (ratios of regional metabolic rates to whole brain rates and asymmetries) in one or more brain regions.

Rumsey, J.M.; Duara, R.; Grady, C.; Rapoport, J.L.; Margolin, R.A.; Rapoport, S.I.; Cutler, N.R.

1985-05-01

333

Lifetime measurements of the 7p levels of atomic francium J. E. Simsarian, L. A. Orozco, G. D. Sprouse, and W. Z. Zhao  

E-print Network

interaction in atomic physics is well understood, radiative lifetimes give information on atomic structure effects are important. Its large number of nucleons and simple atomic structure make it an attractiveLifetime measurements of the 7p levels of atomic francium J. E. Simsarian, L. A. Orozco, G. D

Orozco, Luis A.

334

Measurement of the Lambda(0)(b) lifetime in the decay Lambda(0)(b)-> J/psi Lambda(0) with the D0 detector  

E-print Network

We present measurements of the Lambda(b)(0) lifetime in the exclusive decay channel Lambda(b)(0)-> J/psi Lambda(0), with J/psi ->mu(+)mu(-) and Lambda(0)-> p pi(-), the B-0 lifetime in the decay B-0-> J/psi K-S(0) with ...

Baringer, Philip S.; Bean, Alice; Christofek, L.; Coppage, Don; Gardner, J.; Hensel, Carsten; Jabeen, S.; Wilson, Graham Wallace

2005-03-01

335

Diffusion constant and surface states of positrons in metals  

Microsoft Academic Search

Positron lifetime spectra and angular correlation curves for seven fine-grained powders of Fe, Co, Ni, and W are analyzed.\\u000a From the lifetime data, the positron diffusion constant in metals atT=300K was found to beD\\u000a +=(1.00.5)10?2 cm2 sec?1. Evidence is presented that positrons are trapped in metal surface states.

Robert Paulin; Roger Ripon; Werner Brandt

1974-01-01

336

Lifetime Measurements of Excited States in Neutron-Rich Nuclei Around 48Ca  

Microsoft Academic Search

The lifetimes of the first excited states of the N=30 isotones 50Ca and 51Sc and the Z=18 isotopes 44-46Ar isotopes have been determined using a novel technique that combines the Recoil Distance Doppler Shift method with the CLARA-PRISMA spectrometers in multinucleon transfer reactions. The results allow determinination of the effective charges above 48Ca and test the strength of the N=28

D. Mengoni; J. J. Valiente-Dobón; A. Gadea; E. Farnea; S. M. Lenzi; S. Lunardi; A. Dewald; T. Pissulla; S. Szilner; A. M. Stefanini; R. Broda; F. Recchia; A. Algora; L. Angus; S. Aydin; D. Bazzacco; G. Benzoni; P. G. Bizzeti; A. M. Bizzeti-Sona; P. Boutachkov; L. Corradi; F. Crespi; G. de Angelis; E. Fioretto; A. Görgen; M. Gorska; A. Gottardo; E. Grodner; A. Howard; W. Królas; S. Leoni; P. Mason; R. Menegazzo; D. Montanari; G. Montagnoli; D. R. Napoli; A. Obertelli; T. Pawlat; B. Rubio; E. Sahin; F. Scarlassara; J. F. Smith; D. Steppenbeck; C. A. Ur; P. T. Wady; J. Wrzesinski

2009-01-01

337

Measurement of D0 lifetime with the BaBar detector  

SciTech Connect

This work is the result of the researchers carried out during a three years Ph.D. period in the BABAR experiment. The first chapter consists in an introduction to the theoretical aspects of the D{sup 0} meson lifetime determination and CP violation parameters, as well as an overview of the CP violation in the B sector, which is the main topic of the experiment. The description of the experimental apparatus follows with particular attention to the Silicon Vertex Tracker detector, the most critical detector for the determination of decay vertices and thus of lifetimes and time dependent CP violation asymmetries. In the fourth chapter the operation and running of the vertex detector is described, as a result from the experience as Operation Manager of the SVT, with particular attention to the safety of the device and the data quality assurance. The last chapter is dedicated to the determination of the D{sup 0} meson lifetime with the BABAR detector, which is the main data analysis carried out by the candidate. The analysis is characterized by the selection of an extremely pure sample of D{sup 0} mesons for which the decay flight length and proper time is reconstructed. The description of the unbinned maximum likelihood fit follows, as well as the discussion of the possible sources of systematic uncertainties. In the appendix is also presented a preliminary study of a possible development regarding the determination of mixing and CP violation parameters for the D{sup 0} meson.

Simi, Gabriele; /Pisa U. /SLAC

2009-12-17

338

First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV.  

PubMed

A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ? 250??GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena. PMID:25166975

Aguilar, M; Alberti, G; Alpat, B; Alvino, A; Ambrosi, G; Andeen, K; Anderhub, H; Arruda, L; Azzarello, P; Bachlechner, A; Barao, F; Baret, B; Barrau, A; Barrin, L; Bartoloni, A; Basara, L; Basili, A; Batalha, L; Bates, J; Battiston, R; Bazo, J; Becker, R; Becker, U; Behlmann, M; Beischer, B; Berdugo, J; Berges, P; Bertucci, B; Bigongiari, G; Biland, A; Bindi, V; Bizzaglia, S; Boella, G; de Boer, W; Bollweg, K; Bolmont, J; Borgia, B; Borsini, S; Boschini, M J; Boudoul, G; Bourquin, M; Brun, P; Buénerd, M; Burger, J; Burger, W; Cadoux, F; Cai, X D; Capell, M; Casadei, D; Casaus, J; Cascioli, V; Castellini, G; Cernuda, I; Cervelli, F; Chae, M J; Chang, Y H; Chen, A I; Chen, C R; Chen, H; Cheng, G M; Chen, H S; Cheng, L; Chernoplyiokov, N; Chikanian, A; Choumilov, E; Choutko, V; Chung, C H; Clark, C; Clavero, R; Coignet, G; Commichau, V; Consolandi, C; Contin, A; Corti, C; Costado Dios, M T; Coste, B; Crespo, D; Cui, Z; Dai, M; Delgado, C; Della Torre, S; Demirkoz, B; Dennett, P; Derome, L; Di Falco, S; Diao, X H; Diago, A; Djambazov, L; Díaz, C; von Doetinchem, P; Du, W J; Dubois, J M; Duperay, R; Duranti, M; D'Urso, D; Egorov, A; Eline, A; Eppling, F J; Eronen, T; van Es, J; Esser, H; Falvard, A; Fiandrini, E; Fiasson, A; Finch, E; Fisher, P; Flood, K; Foglio, R; Fohey, M; Fopp, S; Fouque, N; Galaktionov, Y; Gallilee, M; Gallin-Martel, L; Gallucci, G; García, B; García, J; García-López, R; García-Tabares, L; Gargiulo, C; Gast, H; Gebauer, I; Gentile, S; Gervasi, M; Gillard, W; Giovacchini, F; Girard, L; Goglov, P; Gong, J; Goy-Henningsen, C; Grandi, D; Graziani, M; Grechko, A; Gross, A; Guerri, I; de la Guía, C; Guo, K H; Habiby, M; Haino, S; Hauler, F; He, Z H; Heil, M; Heilig, J; Hermel, R; Hofer, H; Huang, Z C; Hungerford, W; Incagli, M; Ionica, M; Jacholkowska, A; Jang, W Y; Jinchi, H; Jongmanns, M; Journet, L; Jungermann, L; Karpinski, W; Kim, G N; Kim, K S; Kirn, Th; Kossakowski, R; Koulemzine, A; Kounina, O; Kounine, A; Koutsenko, V; Krafczyk, M S; Laudi, E; Laurenti, G; Lauritzen, C; Lebedev, A; Lee, M W; Lee, S C; Leluc, C; León Vargas, H; Lepareur, V; Li, J Q; Li, Q; Li, T X; Li, W; Li, Z H; Lipari, P; Lin, C H; Liu, D; Liu, H; Lomtadze, T; Lu, Y S; Lucidi, S; Lübelsmeyer, K; Luo, J Z; Lustermann, W; Lv, S; Madsen, J; Majka, R; Malinin, A; Mańá, C; Marín, J; Martin, T; Martínez, G; Masciocchi, F; Masi, N; Maurin, D; McInturff, A; McIntyre, P; Menchaca-Rocha, A; Meng, Q; Menichelli, M; Mereu, I; Millinger, M; Mo, D C; Molina, M; Mott, P; Mujunen, A; Natale, S; Nemeth, P; Ni, J Q; Nikonov, N; Nozzoli, F; Nunes, P; Obermeier, A; Oh, S; Oliva, A; Palmonari, F; Palomares, C; Paniccia, M; Papi, A; Park, W H; Pauluzzi, M; Pauss, F; Pauw, A; Pedreschi, E; Pensotti, S; Pereira, R; Perrin, E; Pessina, G; Pierschel, G; Pilo, F; Piluso, A; Pizzolotto, C; Plyaskin, V; Pochon, J; Pohl, M; Poireau, V; Porter, S; Pouxe, J; Putze, A; Quadrani, L; Qi, X N; Rancoita, P G; Rapin, D; Ren, Z L; Ricol, J S; Riihonen, E; Rodríguez, I; Roeser, U; Rosier-Lees, S; Rossi, L; Rozhkov, A; Rozza, D; Sabellek, A; Sagdeev, R; Sandweiss, J; Santos, B; Saouter, P; Sarchioni, M; Schael, S; Schinzel, D; Schmanau, M; Schwering, G; Schulz von Dratzig, A; Scolieri, G; Seo, E S; Shan, B S; Shi, J Y; Shi, Y M; Siedenburg, T; Siedling, R; Son, D; Spada, F; Spinella, F; Steuer, M; Stiff, K; Sun, W; Sun, W H; Sun, X H; Tacconi, M; Tang, C P; Tang, X W; Tang, Z C; Tao, L; Tassan-Viol, J; Ting, Samuel C C; Ting, S M; Titus, C; Tomassetti, N; Toral, F; Torsti, J; Tsai, J R; Tutt, J C; Ulbricht, J; Urban, T; Vagelli, V; Valente, E; Vannini, C; Valtonen, E; Vargas Trevino, M; Vaurynovich, S; Vecchi, M; Vergain, M; Verlaat, B; Vescovi, C; Vialle, J P; Viertel, G; Volpini, G; Wang, D; Wang, N H; Wang, Q L; Wang, R S; Wang, X; Wang, Z X; Wallraff, W; Weng, Z L; Willenbrock, M; Wlochal, M; Wu, H; Wu, K Y; Wu, Z S; Xiao, W J; Xie, S; Xiong, R Q; Xin, G M; Xu, N S; Xu, W; Yan, Q; Yang, J; Yang, M; Ye, Q H; Yi, H; Yu, Y J; Yu, Z Q; Zeissler, S; Zhang, J G; Zhang, Z; Zhang, M M; Zheng, Z M; Zhuang, H L; Zhukov, V; Zichichi, A; Zuccon, P; Zurbach, C

2013-04-01

339

Total cross sections for positrons scattered elastically from helium based on new measurements of total ionization cross sections  

NASA Technical Reports Server (NTRS)

An improved technique is presented for employing the 2.3m spectrometer to measure total ionization cross sections, Q sub ion, for positrons incident on He. The new ionization cross section agree with the values reported earlier. Estimates are also presented of total elastic scattering cross section, Q sub el, obtained by subtracting from total scattering cross sections, Q sub tot, reported in the literature, the Q sub ion and Q sub Ps (total positronium formation cross sections) and total excitation cross sections, Q sub ex, published by another researcher. The Q sub ion and Q sub el measured with the 3m high resolution time-of-flight spectrometer for 54.9eV positrons are in accord with the results from the 2.3m spectrometer. The ionization cross sections are in fair agreement with theory tending for the most part to be higher, especially at 76.3 and 88.5eV. The elastic cross section agree quite well with theory to the vicinity of 50eV, but at 60eV and above the experimental elastic cross sections climb to and remain at about 0.30 pi a sub o sq while the theoretical values steadily decrease.

Diana, L. M.; Chaplin, R. L.; Brooks, D. L.; Adams, J. T.; Reyna, L. K.

1990-01-01

340

Measuring the lifetime of silicon nanocrystal solar cell photo-carriers by using Kelvin probe force microscopy and x-ray photoelectron spectroscopy.  

PubMed

We report the first measurements of photo-carrier lifetimes in silicon nanocrystal-based third generation solar cells by Kelvin force microscopy and x-ray photoelectron spectroscopy under modulated frequency light illumination. A high concentration of active defects at the interface between the nanocrystals and silicon oxide matrix may be passivated by annealing under hydrogen. We found that the carrier lifetime, ?, is ? = 7 × 10(-5) s and ? = 3.5 × 10(-5) s within 10% accuracy for the hydrogen passivated and non-passivated nanocrystals, respectively. We used an exponential model to confirm the experimental potential measurements and to estimate photo-carrier lifetimes. PMID:24916454

Borowik, L; Lepage, H; Chevalier, N; Mariolle, D; Renault, O

2014-07-01

341

Measurement of the B-s(0) lifetime in the exclusive decay channel B-s(0)-> J/psi phi  

E-print Network

s lifetime, .0028.0133B 0 s .0134.01361:444 .01350:098 .02550:090 .0133stat.0134.00060:020.0133sys.0134 ps. We also report a measurement for the lifetime of the B 0 meson using the exclusive decay B 0 ! J= .0133.0022 .0135 .0022 .0255 .0134K .00030 .0133892... and proper decay lengths. We also measure the lifetime of the B 0 meson in the exclusive decay