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1

Positron lifetime measurements by proton capture  

NASA Astrophysics Data System (ADS)

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

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

2005-03-01

2

Positron lifetime measurements in chiral nematic liquid crystals  

NASA Technical Reports Server (NTRS)

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

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

1991-01-01

3

Positron Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

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

Martin, Jacob; Jaeger, Herbert

2010-04-01

4

Positron Lifetime Measurements in Natural Rubber with Different Fillers  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectra (PLAS) have been measured for natural rubber polymer with different fillers (Titenium dioxide, Nanosilica and Nanoclay) as a function of filler concentration to investigate how these fillers affect the microstructure of free volume of natural rubber. The lifetime spectra is analyzed by using LT9.0 and the longest lived component(?o-Ps) is attributed to the pick- off annihilation of o-Ps in free volume sites, available mostly in the amorphous region of polymer. On the basis of the ?o-Ps values the radii of the free volume holes (Rh) are calculated. The PALS results show that o-Ps lifetime as well as the size of free volume decreases with the increase of filler concentration.

Mandal, A.; Mukherjee, S.; Pan, S.; Sengupta, A.

5

Tomographic Positron Annihilation Lifetime Spectroscopy  

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

6

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

NASA Astrophysics Data System (ADS)

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

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

2013-11-01

7

Thermal vacancies and positron-lifetime measurements in Fe sub 76. 3 Al sub 23. 7  

SciTech Connect

The formation of thermal vacancies in the intermetallic compound Fe{sub 76.3}Al{sub 23.7} was investigated between 20 and 1060 {degree}C by positron-lifetime measurements. The positron lifetime {tau}{sub {ital f}}=112 ps at 20 {degree}C indicates that no structural vacancies can be detected. The increase of the mean positron lifetime {bar {tau}} due to thermal vacancy formation starts at relatively low temperatures ({ital T}{sub 3}=475 {degree}C). The fit of a simple two-state trapping model to the temperature variation of {bar {tau}} yields an effective vacancy formation enthalpy {ital H}{sup {ital F}}=1.18{plus minus}0.04 eV, which suggests a thermal vacancy concentration at the melting temperature of several atomic percent which is much higher than in pure metals and similar to that found in some intermetallic compounds with a {ital B}2 structure. From a comparison with self-diffusion results, a vacancy migration enthalpy of {ital H}{sup {ital M}}=1.4--1.6 eV is deduced. The phase transitions in the present alloy are discussed in terms of vacancy formation and migration.

Schaefer, H.; Wuerschum, R. (Institut fuer Theoretische und Angewandte Physik, Universitaet Stuttgart, Postfach 801140, D-7000 Stuttgart 80 (Federal Republic of Germany)); Sob, M.; Zak, T. (Institute of Metallurgy, Czechoslovak Academy of Sciences, Zizkova 22, CS-61662 Brno (Czechoslovakia)); Yu, W.Z. (Department of Physics, Qinghua University, Beijing 100084 (People's Republic of China)); Eckert, W. (Institut fuer Theoretische und Angewandte Physik, Universitaet Stuttgart, Postfach 801140, D-7000 Stuttgart 80 (Federal Republic of Germany)); Banhart, F. (Institut fuer Physik, Max-Planck-Institut fuer Metallforschung, D-7000 Stuttgart 80 (Federal Republic of Germany))

1990-06-15

8

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

Microsoft Academic Search

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

H.-E. Schaefer

1991-01-01

9

Application possibilities of Acqiris digital card DP240 for positron lifetime measurement  

NASA Astrophysics Data System (ADS)

Based on existing knowledge, a software for the digital positron lifetime (LT) spectrometer has been designed at the Slovak University of Technology. As a digitizer, Acqiris DP240 card was used. Start and stop timing signals have been digitised separately with sampling rate 1GS/s in 8 bit resolution. This sampling rate was not sufficient; therefore a joined delayed channel mode with 2GS/s sampling rate was used. Next applications for the study of advanced materials for nuclear industry are foreseen.

Petriska, M.; Sluge?, V.; Kršjak, V.; Zeman, A.

2011-01-01

10

A study of annealing stages in Al–Mn (3004) alloy after cold rolling using positron annihilation lifetime technique and Vickers microhardness measurements  

Microsoft Academic Search

Positron annihilation lifetime (PAL), scanning electron microscope (SEM) and Vickers microhardness (Hv) measurements have been performed to study the isochronal annealing of Al–Mn (3004) alloy in the temperature range from RT to 823K after cold rolling at RT with various deformations of 7 and 23%. A positive correlation has been found between average lifetime (?av) of positrons and Vickers microhardness.Three

E. Gomaa; M. Mohsen; A. S. Taha; M. M. Mostafa

2003-01-01

11

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

12

Positron lifetime studies in thermoplastic polyimide test specimens  

NASA Technical Reports Server (NTRS)

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

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

1982-01-01

13

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

14

Slow positron beam generator for lifetime studies  

NASA Technical Reports Server (NTRS)

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

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

1991-01-01

15

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

16

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

17

Photon-induced positron annihilation lifetime spectroscopy using an S-band compact electron linac  

NASA Astrophysics Data System (ADS)

A new photon-induced positron annihilation lifetime spectroscopy approach has been developed using an S-band compact electron linac at the National Institute of Advanced Industrial Science and Technology (AIST). The high energy (<42MeV), intense (105 photons pulse-1), and ultra-short pulse (3 ps pulse width) photon beam creates positrons throughout an entire sample via pair production. A positron lifetime spectrum can be obtained by measuring the time difference between the accelerator's RF frequency and the detection time of the annihilation gamma rays. The positron lifetimes for lead and yttria-stabilized zirconia samples have been successfully measured.

Taira, Y.; Kuroda, R.; Tanaka, M.; Kumaki, M.; Oshima, N.; O'Rourke, B. E.; Suzuki, R.; Toyokawa, H.

2014-02-01

18

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

19

Defects in electron-irradiated Si studied by positron-lifetime spectroscopy  

Microsoft Academic Search

Differently doped and undoped silicon was irradiated with electrons to study the formation of nonequilibrium defects and their annealing behavior. The annealing curves, measured by positron lifetime and also partly by the shape parameters of the Doppler-broadened annihilation line, depend strongly on the doping concentration and the oxygen content. In addition, temperature-dependent positron-lifetime measurements starting at 15 K were performed

A. Polity; F. Börner; S. Huth; S. Eichler; R. Krause-Rehberg

1998-01-01

20

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

21

Microstructural origin of the dielectric breakdown strength in alumina: A study by positron lifetime spectroscopy  

Microsoft Academic Search

The dielectric breakdown strengths of two series of sintered alumina samples of low and high impurity content (with Si being the dominant element) and single crystal of low impurity level are compared with positron lifetime measurements. It is found that, in sintered alumina, the breakdown strength increases linearly with increasing concentration of positron traps at grain boundaries. These traps are

A. Si Ahmed; J. Kansy; K. Zarbout; G. Moya; J. Liebault; D. Gœuriot

2005-01-01

22

Slow Positron Beam Generator for Lifetime Studies.  

National Technical Information Service (NTIS)

A slow positron beam generator using well-annealed polycrystalline tungsten moderators and a Na-22 positron source was developed. A 250 micro c source, deposited on a 2.54 micrometer thick aluminized mylar, is sandwiched between two (2.54 cm x 2.54 cm x 0...

J. J. Singh A. Eftekhari T. L. St. Clair

1989-01-01

23

Positron lifetime spectroscopy for investigation of thin polymer coatings  

NASA Technical Reports Server (NTRS)

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

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

1993-01-01

24

Positron lifetime calculation for defects and defect clusters in graphite  

NASA Astrophysics Data System (ADS)

Calculations of positron lifetime have been made for vacancy type defects in graphite and compared with experimental results. Defect structures were obtained in a model graphite lattice after including relaxation of whole lattice as determined by the molecular dynamics method, where the interatomic potential given by Pablo Andribet, Dominguez-Vazguez, Mari Carmen Perez-Martin, Alonso, Jimenez-Rodriguez [Nucl. Instrum. and Meth. 115 (1996) 501] was used. For the defect structures obtained via lattice relaxation positron lifetime was calculated under the so-called atomic superposition method. Positron lifetimes 204 and 222 ps were obtained for the graphite matrix and a single vacancy, respectively, which can be compared with the experimental results 208 and 233 ps. For planar vacancy clusters, e.g., vacancy loops, lifetime calculation was also made and indicated that lifetime increases with the number of vacancies in a cluster. This is consistent with the experimental result in the region of higher annealing temperature (above 1200°C), where the increase of positron lifetime is seen, probably corresponding to the clustering of mobile vacancies.

Onitsuka, T.; Ohkubo, H.; Takenaka, M.; Tsukuda, N.; Kuramoto, E.

2000-12-01

25

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

26

Positron lifetime studies in vinyl polymers of medical importance  

NASA Astrophysics Data System (ADS)

Vinyl polymers used as artificial lens implants in ophthalmology were investigated by positron lifetime spectroscopy. The structure of these polymers with free volumes offers the possibility of charging them with anti-inflammatory drugs for sustained release. A correlation between the amount of normalised free volume and the ratio of the methyl methacrylate to ethyl-hexyl-acrylate, used as polymerisation monomers, was found.

Ferreira Marques, M. F.; Gordo, P. M.; Gil, C. Lopes; Kajcsos, Zs.; Gil, M. H.; Mariz, M. J.; de Lima, A. P.

2003-10-01

27

Various types of polysiloxanes studied by positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

In the work, linear poly(vinylsiloxanes) with regular distributions of vinyl groups along chains, the networks obtained by their hydrosilylation with various hydrogensiloxanes, products of pyrolysis of such networks as well as the networks prepared via reaction of low-molecular siloxanes have been studied by positron anihilation lifetime spectroscopy (PALS).

Nyczyk-Malinowska, Anna; Dryzek, Ewa; Hasik, Magdalena; Dryzek, Jerzy

28

Location of solubilizate in water-AOT-isooctane systems using positron lifetime spectroscopy  

Microsoft Academic Search

In the present work, positrons have been used as a probe to locate the interaction site of the additive molecules in a membrane mimetic system similar to reverse micelles. The systems investigated are water-AOT Aerosol OT [Sodium bis(2-ethylhexyl) sulfosuccinate)-isooctane solutions. Positron lifetime measurements have been performed in water-AOT-isooctane solutions containing chloroform and dichloromethane, respectively, as additives. The choice of these

M. Zaboli; P. C. Jain; A. N. Maitra

1991-01-01

29

Measurement of the ? lifetime  

Microsoft Academic Search

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

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

1993-01-01

30

TRENDS IN LIFETIME MEASUREMENTS  

Microsoft Academic Search

The interpretation of lifetime measurements and new characterization techniques are addressed in this paper. Parameters such as sur- face\\/interface recombination, sample thickness, and injection level are dis- cussed. Novel characterization techniques using frequency-dependent ca- pacitance, conductance, or impedance measurements are described and are shown to be useful for thin layer, e.g., epitaxial or silicon-on-insulator lay- ers, characterization.

Dieter K. Schroder

31

The temperature dependence of positron lifetimes in solid pivalic acid  

NASA Astrophysics Data System (ADS)

The temperature dependence of positron lifetimes in both the brittle and plastic phases of trimethylacetic (pivalic) acid has been examined using the positron lifetime technique. In the plastic phase two long-lived components attributable to ortho-positronium (ortho-Ps) decay are observed. The longer of these (?2.8 ns) increases with temperature and is believed to be characteristic of ortho-Ps trapped at defects, probably mono- and di-vacancies. A shorter lifetime component (?1 ns) which shows little temperature dependence is also present in the brittle phase. Additionally in the brittle phase and close to the transition region a longer lifetime is detected. This may also be associated with trapping of ortho-Ps in thermally created defects, probably vacancies. In the plastic phase the intensity of a short-lived component associated with para-Ps is confirmed to be approximately one third of the total intensity of the two long-lived components associated with ortho-Ps, but in the brittle phase it higher than one third. On using data for several plastic crystals a relationship is established between the lifetime of ortho-Ps trapped in a vacancy and the vacancy volume. Trimethylacetic acid; 2,2-dimethylpropanoic acid.

Eldrup, M.; Lightbody, D.; Sherwood, J. N.

1981-12-01

32

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

33

A positron lifetime study of the electron-beam-induced polymerization of 1,6-hexanediol diacrylate  

Microsoft Academic Search

Positron lifetime measurements have been used to characterize the electron-beam-induced polymerization of 1,6-hexanediol diacrylate (HDODA). Lifetimes were measured as a function of radiation dose over a range of 0.5–7.0 Mrad and analyzed into three components. All three components exhibited some variation with radiation dose. Variations in the longest lifetime component have been interpreted in terms of changes in free volume.

William W. Walker; James W. Harrell

1991-01-01

34

Charm lifetime measurements from TASSO  

SciTech Connect

Recent measurements by TASSO of the lifetimes of charmed mesons is reviewed. The lifetime reported for the D/sub s/ meson utilizes the entire data sample collected. The lifetime of the neutral charmed meson, D/sup o/, is from a subsample of the total data set. Special emphases is given to the experimental procedures used.

Forden, G.E.

1987-10-09

35

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

36

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

Microsoft Academic Search

A new positron annihilation lifetime spectrometer consisting of a start gamma-ray detector, a stop gamma-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. gamma-ray signals related to positrons annihilating in the positron detector

Masato Yamawaki; Yoshinori Kobayashi; Kanehisa Hattori; Yoshihiro Watanabe

2011-01-01

37

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

SciTech Connect

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

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

1998-09-04

38

Portable Positron Measurement System (PPMS)  

ScienceCinema

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

39

Portable Positron Measurement System (PPMS)  

ScienceCinema

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

None

2013-05-28

40

Portable Positron Measurement System (PPMS)  

SciTech Connect

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

None

2011-01-01

41

Positron annihilation lifetime spectroscopy of ZnO bulk samples  

SciTech Connect

In order to gain a further insight into the knowledge of point defects of ZnO, positron annihilation lifetime spectroscopy was performed on bulk samples annealed under different atmospheres. The samples were characterized at temperatures ranging from 10 to 500 K. Due to difficulties in the conventional fitting of the lifetime spectra caused by the low intensity of the defect signals, we have used an alternative method as a solution to overcome these difficulties and resolve all the lifetime components present in the spectra. Two different vacancy-type defects are identified in the samples: Zn vacancy complexes (V{sub Zn}-X) and vacancy clusters consisting of up to five missing Zn-O pairs. In addition to the vacancies, we observe negative-ion-type defects, which are tentatively attributed to intrinsic defects in the Zn sublattice. The effect of the annealing on the observed defects is discussed. The concentrations of the V{sub Zn}-X complexes and negative-ion-type defects are in the 0.2-2 ppm range, while the cluster concentrations are 1-2 orders of magnitude lower.

Zubiaga, A.; Plazaola, F.; Garcia, J. A.; Tuomisto, F.; Munoz-Sanjose, V.; Tena-Zaera, R. [Fisika Aplikatua II Saila, Euskal Herriko Unibertsitatea, Posta Kutxatila 644, 48080 Bilbao (Spain); Laboratory of Physics, Helsinki University of Technology, P.O. Box 1100, 02015 TKK, Espoo (Finland); Departament de Fisica Aplicada i Electromagnetisme, c/ Doctor Moliner 50, E-46100 Burjassot, Valencia (Spain)

2007-08-15

42

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

PubMed

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. PMID:24815814

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

2014-08-14

43

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

44

Measurement of the ?+c lifetime  

NASA Astrophysics Data System (ADS)

A precise measurement of the ?+c lifetime using approximately 1340 fully reconstructed ?+c-->pK-?+ and charge conjugate decays is presented. The data were accumulated by the Fermilab high energy photoproduction experiment E687. The lifetime of the ?+c is measured to be 0.215+/-0.016+/-0.008 ps.

Frabetti, P. L.; Cheung, H. W.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Greene, S. V.; Johns, W. E.; Nehring, M. S.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garren, L.; Garbincius, P. H.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Culbertson, R.; Gardner, R. W.; Greene, R.; Wiss, J.; Alimonti, G.; Bellini, G.; Caccianiga, B.; Cinquini, L.; di Corato, M.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Moroni, L.; Pedrini, D.; Perasso, L.; Sala, A.; Sala, S.; Toretta, D.; Vittone, M.; Buchholz, D.; Claes, D.; Gobbi, B.; O'reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Mannel, E. J.; Puseljic, D. L.; Ruchti, R. C.; Shephard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Castoldi, C.; Diaferia, R.; Gianini, G.; Ratti, S. P.; Riccardi, C.; Vitulo, P.; Lopez, A.; Grim, G. P.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Sheldon, P. D.; Davenport, F.; Filasetta, J. F.; Blackett, G. R.; Pisharody, M.; Handler, T.; Cheon, B. G.; Kang, J. S.; Kim, K. Y.

1993-03-01

45

Successful implementation of fast preamplifiers in a positron lifetime spectrometer  

NASA Astrophysics Data System (ADS)

A method to improve the long-term stability of fast coincidence apparatuses, like a positron lifetime spectrometer, is reported. Ageing of the photomultiplier tubes (PMT), i.e., nonreversible degradation of the gain, can be slowed down by lowering the supply voltages over the PMTs and by compensating the lower gain with fast preamplifiers set at the anodes. The timing characteristics of the PMTs can be preserved by using voltage dividers with which the voltage in the input optics of the PMTs remains high enough for good photoelectron collection efficiency (for XP2020 above 300 V). With this setup, the anode current and the rate of gain degradation can be reduced at least by a factor of 20 with no loss in the time resolution of the spectrometer.

Nissilä, J.; Rytsölä, K.; Saarinen, K.; Hautojärvi, P.

2002-04-01

46

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

47

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

SciTech Connect

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

J.M. Urban-Klaehn

2007-09-01

48

Observation of AsGrown Defects in Zn-Doped GaAs by Positron Lifetime Spectra  

Microsoft Academic Search

Positron lifetime spectra were measured for the Zn-doped p-type GaAs. In comparing the horizontal-Bridgman-method-grown and the floating-zone-method grown p-type GaAs with the liquid-encapsulation-Czochralski-grown p-type GaAs samples, positron trapping into vacancy type defects was observed in the former two grown p-type GaAs. Shallow positron traps were detected, and the dominant ones were attributed to acceptor the in p-type GaAs. Bibtex entry

Zhu Wang; Shao-Jie Wang; Zhi-Quan Chen

2000-01-01

49

Observation of As-Grown Defects in Zn-Doped GaAs by Positron Lifetime Spectra  

NASA Astrophysics Data System (ADS)

Positron lifetime spectra were measured for the Zn-doped p-type GaAs. In comparing the horizontal-Bridgman-method-grown and the floating-zone-method grown p-type GaAs with the liquid-encapsulation-Czochralski-grown p-type GaAs samples, positron trapping into vacancy type defects was observed in the former two grown p-type GaAs. Shallow positron traps were detected, and the dominant ones were attributed to acceptor the in p-type GaAs.

Wang, Zhu; Wang, Shao-Jie; Chen, Zhi-Quan

2000-11-01

50

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

51

Updated measurement of the ? lifetime  

NASA Astrophysics Data System (ADS)

We present an update of our measurement of the ? 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 ? decays to a single charged particle, and the reconstructed decay lenghts from the ? decays to three charged particles. With the added statistics (which increase the ? pair event sample size by more than a factor of four over our 1990 and 1991 data sample), the updated lifetime measurement is: ?? = 288.8 ± 2.2 (stat) ± 1.4 (sys) fs. When combined with world-average measurements of the tau leptonic branching fractions (assuming e-? universality), the ratio of charged-current couplings is: ( {g ?}/{g ?}) = 1.005 ± 0.007 , in agreement with the hypothesis of ?-? charged-current universality.

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

1994-11-01

52

Measurement of lifetime alcohol consumption.  

PubMed

The reliability and validity of a retrospective, self-report measure, the Concordia Lifetime Drinking Questionnaire (CLDQ), were assessed with a group of 72 elderly Canadian men. The CLDQ includes quantity and frequency questions on current beverage-specific alcohol use and a series of questions about the start of alcohol use. The innovative features of the CLDQ include requiring subjects to collaborate with the interviewer in drawing a graph that represents their lifetime drinking patterns and encouraging more accurate recall by the use of salient events in the subject's life history. Drinking was assessed on two occasions approximately 33 months apart. Forty-six wives responded to questions about their husband's drinking. The reliability coefficient for lifetime drinking was .78. A comparison of the two graphs every fifth year from 1945 to 1985 yielded significant correlations that ranged from .65 to .87. Validity was tested by comparing each wife's rating of her husband's drinking at present and at time of marriage with similar points on the husband's graphs; the correlations were .87 and .72, respectively. Moderate correlations were obtained between the MAST and the CLDQ. The CLDQ was judged to be a reliable and valid measure of lifetime drinking, appropriate for use with the elderly. The longitudinal lifetime drinking patterns appeared similar to those found in cross-sectional studies. PMID:8189733

Chaikelson, J S; Arbuckle, T Y; Lapidus, S; Gold, D P

1994-03-01

53

Characterization of radiation-induced lattice vacancies in intermetallic compounds by means of positron-lifetime studies  

NASA Astrophysics Data System (ADS)

In the present paper a characterization of atomic vacancies in intermetallic compounds is given by means of positron-lifetime measurements after electron irradiation and comparison with the states after preparation, after long-time annealing, or in high-temperature equilibrium. In TiAl, Ti3Al, and Ni3Al no structural vacancies (detection limit CV=10-6) are observed at ambient temperature. This confirms that in these compounds slight deviations from stoichiometry are compensated by antisite atoms. In the Al-poor B2 alloys FeAl and NiAl, on the other hand, remnant vacancies exist due to the high thermal equilibrium vacancy concentrations and their slow diffusivities. The kinetics of vacancy elimination in FeAl and NiAl is discussed. A substantial temperature dependence of the positron lifetime in vacancies is detected in close-packed intermetallics which is attributed to an increased atomic relaxation or partial positron detrapping at high temperatures. In contrast to that, the temperature dependence of the positron lifetime in vacancies is small in the open-structured B2 aluminides. The lifetimes ?f of free delocalized positrons in transition-metal aluminides and in NiZr and NiTi can be correlated to those of the pure components, taking into account the densities of valence electrons. For the positron lifetimes ?1 of vacancies in intermetallic compounds, values of ?1/?f=1.5-1.7 are observed similar as in the pure metals. Annealing studies of B2-FeAl after electron irradiation yield time constants for the disappearance of vacancies identical to those deduced recently for the equilibration of thermal vacancies. In electron-irradiated Ti aluminides annealing processes at 250 K and 450 K are observed where the latter process is tentatively attributed to long-range migration of vacancies.

Würschum, R.; Badura-Gergen, K.; Kümmerle, E. A.; Grupp, C.; Schaefer, H.-E.

1996-07-01

54

Measurement of Charm Meson Lifetimes  

SciTech Connect

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

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

1999-06-01

55

Electronic structure calculations of positron lifetimes in nuclear materials: SiC and UO2  

NASA Astrophysics Data System (ADS)

We present first-principles calculations of positron lifetimes of vacancy-type defects in two nuclear materials: SiC and UO2. We use a self-consistent positron lifetime calculation scheme based on the two-component density functional theory. Full defect relaxation due to both the creation of the vacancy and the presence of the positron was taken into account. Our results for SiC differ strongly from those published in literature up to now [G. Brauer et al. Phys. Rev. B 54, 2512 (1996)]. This is mostly due to the effect of the relaxation, that was not taken into account before. We also present the first calculated positron lifetimes obtained for UO2 in the DFT+U approach. Results are compared with the experimental data.

Wiktor, Julia; Jomard, Gérald; Freyss, Michel; Bertolus, Marjorie

2014-06-01

56

Development of a compact and fast response detector using an Yb:Lu2O3 scintillator for lifetime sensitive positron emission tomography  

NASA Astrophysics Data System (ADS)

We propose a method for obtaining three-dimensional imaging measurements of the defect distribution inside industrial materials by measuring positron lifetimes, in addition to using the imaging technique of positron emission tomography. A compact and fast response detector that uses an Yb3+-doped Lu2O3 scintillator and a photomultiplier tube was developed and tested. Yb3+ charge transfer luminescence exhibits a fast response in the ultraviolet and visible regions. The first measurement of the positron lifetime for a bulk material using an Yb:Lu2O3 scintillator was carried out. The lifetime of positrons created inside an yttria-stabilized zirconia block via pair production produced by ultrashort photon pulses was successfully measured.

Taira, Y.; Kuroda, R.; Tanaka, M.; Oshima, N.; O'Rourke, B. E.; Suzuki, R.; Toyokawa, H.; Watanabe, K.; Yanagida, T.; Yagi, H.; Yanagitani, T.

2014-05-01

57

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

58

A slow positron beam generator for lifetime studies  

Microsoft Academic Search

A slow positron beam generator using well-annealed polycrystalline tungsten moderators and a Na-22 positron source was developed. A 250 micro c source, deposited on a 2.54 micron thick aluminized mylar, is sandwiched between two (2.54 cm x 2.54 cm x 0.0127 cm) tungsten pieces. Two (2.54 cm x 2.54 cm x t cm) test polymer films insulate the two tungsten

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

1989-01-01

59

A slow positron beam generator for lifetime studies  

SciTech Connect

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

Singh, J.J.; Eftekhari, A.; St.Clair, T.L.

1989-04-01

60

A slow positron beam generator for lifetime studies  

NASA Technical Reports Server (NTRS)

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

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

1989-01-01

61

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

PubMed

High-energy ultrashort gamma-ray pulses can be generated via laser Compton scattering with 90° collisions at the UVSOR-II electron storage ring. As an applied study of ultrashort gamma-ray pulses, a new photon-induced positron annihilation lifetime spectroscopy approach has been developed. Ultrashort gamma-ray pulses with a maximum energy of 6.6 MeV and pulse width of 2.2 ps created positrons throughout bulk lead via pair production. Annihilation gamma rays were detected by a BaF2 scintillator mounted on a photomultiplier tube. A positron lifetime spectrum was obtained by measuring the time difference between the RF frequency of the electron storage ring and the detection time of the annihilation gamma rays. We calculated the response of the BaF2 scintillator and the time jitter caused by the variation in the total path length of the ultrashort gamma-ray pulses, annihilation gamma rays, and scintillation light using a Monte Carlo simulation code. The positron lifetime for bulk lead was successfully measured. PMID:23742543

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

2013-05-01

62

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

NASA Astrophysics Data System (ADS)

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

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

2013-05-01

63

Lifetime Measurements in ^71Se  

NASA Astrophysics Data System (ADS)

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

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

2009-10-01

64

Nanoscopic properties of silica filled polydimethylsiloxane by means of positron annihilation lifetime spectroscopy  

Microsoft Academic Search

Positron annihilation lifetime spectroscopy (PALS) was performed on a series of polydimethylsiloxane (PDMS)\\/fumed silicon dioxide (SiO2) composites at temperatures between ?185 and 100°C to study the effect of filler content and filler particle size on the free volume properties and the positron annihilation characteristics. The glass transition behavior of the PDMS\\/SiO2 composites was determined with differential scanning calorimetry. A clear

Petra Winberg; Morten Eldrup; Frans H. J. Maurer

2004-01-01

65

A measurement of the ? lifetime  

Microsoft Academic Search

We have reconstructed 695 three-track ? decay vertices using a high resolution drift chamber close to the interaction point.\\u000a From the distribution of decay lengths we measure the lifetime to be (3.06 ±0.20±0.14)×10?13 s. Using this result we find that the ratio of charged weak coupling constant for the ? to that of the ?,G\\u000a ?\\/G\\u000a ?=0.967±0.040 consistent with the

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

1988-01-01

66

Lifetime measurements for bottom hadrons  

SciTech Connect

The review of lifetime measurements of bottom hadrons begins with a first measurement by JADE, followed by similar measurements by MAC and MKII groups. New MAC data are reviewed based on a total of 75,000 multihadron events taken at a c.m. energy of 29 GeV. According to Monte Carlo calculations, 18% of the lepton candidates stem from charm decay and roughly 30% were misidentified hadrons. DELCO studied electrons obtained from 42,000 multihadron events at 29 GeV. The electrons were identified by means of Cerenkov counters. JADE analayzed 22,000 multihadron events at 35 GeV. Data were analyzed using two methods - one using a sample of b-enriched events, and the other using weighted distributions. The TASSO results were obtained with two different configurations of the detector - one of which used a drift chamber and the other a vertex detector. (LEW)

Wolf, G.

1984-09-01

67

Positron lifetime reveals the nano level packing in complex polysaccharide-rich hydrolysate matrixes.  

PubMed

Positron annihilation lifetime spectroscopy (PALS) was used to quantify the free volume and molecular packing in hydrolysate and hemicellulose-based barriers films, derived from process streams during wood processing operations. These hydrolysate films, comprising a fair share of lignin coexisting with poly- and oligo-saccharides, have very low but variable oxygen permeability but differ among themselves with respect to barrier performance as well as molecular weight, degree of branching, and monosaccharide residue main chain composition. From PALS measurements on hydrolysates, the free volume hole radius (r(h)), radius distributions (n(r(h))), volume-weighted hole sizes ((v)), and hole volume distributions (g(v(h))) were calculated showing that the hydrolysate matrixes are very densely packed with small holes. The results show a clear relationship between hydrolysate molecular architecture and composition, the nanolevel molecular packing, and the ability of suppressing the diffusion of oxygen through the film. PMID:22455471

Edlund, Ulrica; Yu, Yang; Ryberg, Yingzhi Zhu; Krause-Rehberg, Reinhard; Albertsson, Ann-Christine

2012-04-17

68

Electron beam and gamma irradiation effects on high density polyethylene studied via positron annihilation lifetime spectroscopy  

Microsoft Academic Search

Positron annihilation lifetime spectroscopy is applied to the study of electron beam and gamma irradiation effects on high density polyethylene (HDPE). The electron and ?-irradiations were carried out in air, with a flux of 80 kGy s?1 and 26 10?3 kGy s?1, respectively. In four-component analyses of the spectra, two long-lived states are found, with lifetimes ?3=1100 ps and ?4=2570

A. Badia; G. Duplâtre

1999-01-01

69

Positron-annihilation-lifetime response and broadband dielectric relaxation spectroscopy: Diethyl phthalate  

Microsoft Academic Search

We report the results of a combined phenomenological analysis of the data from positron-annihilation-lifetime spectroscopy (PALS) and the relaxation data from broadband dielectric spectroscopy (BDS) on diethyl phthalate (DEP). The ortho-positronium ( o -Ps) lifetime, tau3 , as a function of temperature over a temperature range from 67K up to 300K is compared with the spectral features and the relaxation

J. Bartos; A. Alegría; O. Sausa; M. Tyagi; D. Gómez; J. Kristiak; J. Colmenero

2007-01-01

70

Measurement of Recombination Lifetimes in Superconductors  

Microsoft Academic Search

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

Allen Rothwarf; B. N. Taylor

1967-01-01

71

Microcomputer program for analysis of positron annihilation lifetime spectra  

Microsoft Academic Search

A user friendly program (LT) for analysis of the lifetime spectra has been designed for personal computers. The program is compared with other existing programs such as POSITRONFIT, CONTIN and MELT. LT enables one to analyse both discrete and continuous spectra as well as mixed- partially linear and partially continuous spectra. The searched parameters are found by using a fully

J. Kansy

1996-01-01

72

Resolving Nuclear Reactor Lifetime Extension Questions: A Combined Multiscale Modeling and Positron Characterization approach  

Microsoft Academic Search

The objective of this work is to determine the chemical composition of nanometer precipitates responsible for irradiation hardening and embrittlement of reactor pressure vessel steels, which threaten to limit the operating lifetime of nuclear power plants worldwide. The scientific approach incorporates computational multiscale modeling of radiation damage and microstructural evolution in Fe-Cu-Ni-Mn alloys, and experimental characterization by positron annihilation spectroscopy

B Wirth; P Asoka-Kumar; A Denison; S Glade; R Howell; J Marian; G Odette; P Sterne

2004-01-01

73

On the two-step ageing of a commercial Al - Zn - Mg alloy; a study by positron lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Formation of Guinier - Preston zones and precipitation, induced by two-step ageing thermal treatments in an age-hardenable commercial Al - Zn - Mg-based alloy, have been studied by positron lifetime spectroscopy and Vickers microhardness measurements. In particular, an initial softening of the specimens, occurring in the early stages of the second ageing step (artificial ageing at 0953-8984/8/45/026/img6), appears to be correlated with a strong decrease in the positron lifetime, which indicates a partial dissolution of the GP zones. If the treatment at 0953-8984/8/45/026/img6 is interrupted at this stage, and the ageing continues at a lower temperature (either room temperature or 0953-8984/8/45/026/img8), the positron lifetime and the microhardness recover to the values reached at the end of the first ageing step (natural ageing at room temperature for five days). The kinetics of this process is discussed in terms of reconstruction of GP zones; the activation energy value of this process is also obtained.

Ferragut, R.; Somoza, A.; Dupasquier, A.

1996-11-01

74

Understanding carrier lifetime measurements at nonuniform recombination  

NASA Astrophysics Data System (ADS)

Effective lifetimes as measured via dynamic vs. steady-state techniques may drastically diverge in the presence of a highly nonuniform spatial distribution of excess carrier recombination. Based on a Green's function approach to the continuity equation, simple mode weighting rules were derived for both steady-state effective lifetime and quasi-steady-state harmonically modulated lifetime. Their validity was experimentally confirmed. Such mode weighting rules provide a full quantitative understanding of the mismatch between these two types of effective lifetime. Also, they allow the determination of individual recombination and transport properties from effective lifetimes measured at highly nonuniform configurations of recombination rate.

Giesecke, J. A.; Warta, W.

2014-02-01

75

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.

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

2013-01-01

76

Positron annihilation spectroscopy with magnetically analyzed beams  

NASA Technical Reports Server (NTRS)

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

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

1982-01-01

77

Measurement of the ?-lepton lifetime at Belle.  

PubMed

The lifetime of the ? lepton is measured using the process e+ e- ? ?+ ?- , where both ? leptons decay to 3??(?). The result for the mean lifetime, based on 711??fb(-1) of data collected with the Belle detector at the ?(4S) resonance and 60??MeV below, is ?=(290.17±0.53(stat)±0.33(syst))×10(-15)??s. 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 |??|/?<7.0×10(-3) at 90% C.L. PMID:24484129

Belous, K; Shapkin, M; Sokolov, A; Adachi, I; Aihara, H; Asner, D M; Aulchenko, V; Bakich, A M; Bala, A; Bhuyan, B; Bobrov, A; Bondar, A; Bonvicini, G; Bozek, A; Bra?ko, M; Browder, T E; ?ervenkov, D; Chekelian, V; Chen, A; Cheon, B G; Chilikin, K; Chistov, R; Cho, K; Chobanova, V; Choi, Y; Cinabro, D; Dalseno, J; Doležal, Z; Dutta, D; Eidelman, S; Epifanov, D; Farhat, H; Fast, J E; Ferber, T; Gaur, V; Ganguly, S; Garmash, A; Gillard, R; Goh, Y M; Golob, B; Haba, J; Hara, T; Hayasaka, K; Hayashii, H; Hoshi, Y; Hou, W-S; Iijima, T; Inami, K; Ishikawa, A; Itoh, R; Iwashita, T; Jaegle, I; Julius, T; Kato, E; Kichimi, H; Kiesling, C; Kim, D Y; Kim, H J; Kim, J B; Kim, M J; Kim, Y J; Kinoshita, K; Ko, B R; Kodyš, P; Korpar, S; Križan, P; Krokovny, P; Kuhr, T; Kuzmin, A; Kwon, Y-J; Lange, J S; Lee, S-H; Libby, J; Liventsev, D; Lukin, P; Matvienko, D; Miyata, H; Mizuk, R; Mohanty, G B; Mori, T; Mussa, R; Nagasaka, Y; Nakano, E; Nakao, M; Nayak, M; Nedelkovska, E; Ng, C; Nisar, N K; Nishida, S; Nitoh, O; Ogawa, S; Okuno, S; Olsen, S L; Ostrowicz, W; Pakhlova, G; Park, C W; Park, H; Park, H K; Pedlar, T K; Pestotnik, R; Petri?, M; Piilonen, L E; Ritter, M; Röhrken, M; Rostomyan, A; Ryu, S; Sahoo, H; Saito, T; Sakai, Y; Sandilya, S; Santel, D; Santelj, L; Sanuki, T; Savinov, V; Schneider, O; Schnell, G; Schwanda, C; Semmler, D; Senyo, K; Seon, O; Shebalin, V; Shen, C P; Shibata, T-A; Shiu, J-G; Shwartz, B; Sibidanov, A; Simon, F; Sohn, Y-S; Stani?, S; Stari?, M; Steder, M; Sumiyoshi, T; Tamponi, U; Tatishvili, G; Teramoto, Y; Trabelsi, K; Tsuboyama, T; Uchida, M; Uehara, S; Uglov, T; Unno, Y; Uno, S; Usov, Y; Vahsen, S E; Van Hulse, C; Vanhoefer, P; Varner, G; 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, Y; Yuan, C Z; Zhang, Z P; Zhilich, V; Zupanc, A

2014-01-24

78

Measurement of the ?-lepton Lifetime at Belle  

NASA Astrophysics Data System (ADS)

The lifetime of the ? lepton is measured using the process e+e-??+?-, where both ? leptons decay to 3???. The result for the mean lifetime, based on 711 fb-1 of data collected with the Belle detector at the ?(4S) resonance and 60 MeV below, is ? =290.17±0.53(stat)±0.33(syst) ×10-15 s. 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 |??|/?<7.0×10-3 at 90% C.L.

Belous, K.; Shapkin, M.; Sokolov, A.; Adachi, I.; Aihara, H.; Asner, D. M.; Aulchenko, V.; Bakich, A. M.; Bala, A.; Bhuyan, B.; Bobrov, A.; Bondar, A.; Bonvicini, G.; Bozek, A.; Bra?ko, M.; Browder, T. E.; ?ervenkov, D.; Chekelian, V.; Chen, A.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Cho, K.; Chobanova, V.; Choi, Y.; Cinabro, D.; Dalseno, J.; Doležal, Z.; Dutta, D.; Eidelman, S.; Epifanov, D.; Farhat, H.; Fast, J. E.; Ferber, T.; Gaur, V.; Ganguly, S.; Garmash, A.; Gillard, R.; Goh, Y. M.; Golob, B.; Haba, J.; Hara, T.; Hayasaka, K.; Hayashii, H.; Hoshi, Y.; Hou, W.-S.; Iijima, T.; Inami, K.; Ishikawa, A.; Itoh, R.; Iwashita, T.; Jaegle, I.; Julius, T.; Kato, E.; Kichimi, H.; Kiesling, C.; Kim, D. Y.; Kim, H. J.; Kim, J. B.; Kim, M. J.; Kim, Y. J.; Kinoshita, K.; Ko, B. R.; Kodyš, P.; Korpar, S.; Križan, P.; Krokovny, P.; Kuhr, T.; Kuzmin, A.; Kwon, Y.-J.; Lange, J. S.; Lee, S.-H.; Libby, J.; Liventsev, D.; Lukin, P.; Matvienko, D.; Miyata, H.; Mizuk, R.; Mohanty, G. B.; Mori, T.; Mussa, R.; Nagasaka, Y.; Nakano, E.; Nakao, M.; Nayak, M.; Nedelkovska, E.; Ng, C.; Nisar, N. K.; Nishida, S.; Nitoh, O.; Ogawa, S.; Okuno, S.; Olsen, S. L.; Ostrowicz, W.; Pakhlova, G.; Park, C. W.; Park, H.; Park, H. K.; Pedlar, T. K.; Pestotnik, R.; Petri?, M.; Piilonen, L. E.; Ritter, M.; Röhrken, M.; Rostomyan, A.; Ryu, S.; Sahoo, H.; Saito, T.; Sakai, Y.; Sandilya, S.; Santel, D.; Santelj, L.; Sanuki, T.; Savinov, V.; Schneider, O.; Schnell, G.; Schwanda, C.; Semmler, D.; Senyo, K.; Seon, O.; Shebalin, V.; Shen, C. P.; Shibata, T.-A.; Shiu, J.-G.; Shwartz, B.; Sibidanov, A.; Simon, F.; Sohn, Y.-S.; Stani?, S.; Stari?, M.; Steder, M.; Sumiyoshi, T.; Tamponi, U.; Tatishvili, G.; Teramoto, Y.; Trabelsi, K.; Tsuboyama, T.; Uchida, M.; Uehara, S.; Uglov, T.; Unno, Y.; Uno, S.; Usov, Y.; Vahsen, S. E.; Van Hulse, C.; Vanhoefer, P.; Varner, G.; 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, Y.; Yuan, C. Z.; Zhang, Z. P.; Zhilich, V.; Zupanc, A.; Belle Collaboration

2014-01-01

79

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

80

Measurement time reduction for generation lifetimes  

Microsoft Academic Search

The defect properties of thin semiconductor layers (epitaxial and denuded zones as well as silicon on insulator) are not as easily characterized as those of bulk wafers. Recombination lifetime or diffusion length measurements, routinely used for bulk wafers, are unreliable when the layer thickness is significantly less than the diffusion length. Generation lifetime measurements are eminently suitable for such characterization

Sang-Yun Lee; Dieter K. Schroder

1999-01-01

81

Measurement of the meson lifetime using decays  

NASA Astrophysics Data System (ADS)

The lifetime of the meson is measured using semileptonic decays having a meson and a muon in the final state. The data, corresponding to an integrated luminosity of , are collected by the LHCb detector in collisions at a centre-of-mass energy of 8 TeV. The measured lifetime is where the first uncertainty is statistical and the second is systematic.

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; 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 Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dorosz, P.; 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.; Falabella, A.; Färber, C.; Farinelli, C.; Farry, S.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garra Tico, J.; Garrido, L.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Hafkenscheid, T. W.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Huse, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Kochebina, O.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lowdon, P.; Lu, H.; Lucchesi, D.; Luisier, J.; Luo, H.; Luppi, E.; Lupton, O.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.

2014-05-01

82

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

NASA Astrophysics Data System (ADS)

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

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

2012-06-01

83

Investigation on CO 2-induced plasticization in polycarbonate membrane using positron annihilation lifetime spectroscopy  

Microsoft Academic Search

In this study, the microstructural changes in polycarbonate (PC) membranes induced by the CO2 sorption were investigated using the CO2 sorption isotherm data and the positron annihilation lifetime spectroscopy (PALS). The effects of the PC exposure to CO2 at different temperatures and gas pressures on the free-volume distribution were discussed. The distribution at ambient conditions or 5atm He pressure displayed

Chia-Hao Lo; Wei-Song Hung; Manuel De Guzman; Shu-Hsien Huang; Chi-Lan Li; Chien-Chieh Hu; Yan-Ching Jean; Kueir-Rarn Lee; Juin-Yih Lai

2010-01-01

84

A simplified digital positron lifetime spectrometer based on a fast digital oscilloscope  

NASA Astrophysics Data System (ADS)

A simplified digital positron lifetime spectrometer is presented and tested. This system is only composed of two scintillation detectors, a time delayer and a digital oscilloscope. Both online and offline analysis of the detector signals can be optionally chosen to construct positron lifetime spectrum by histogramming the time difference between the positron birth signal of 1.27 MeV ?-ray and one positron annihilation signal of 0.511 MeV ?-rays. Several pulse discrimination methods and timing numerical algorithms are proposed and well applied to perform pulse energy discrimination and digital constant fraction timing (DCFT). A combination discrimination of pulse amplitude, pulse risetime and ratio of pulse area to pulse amplitude with DCFT is found able to achieve the best time resolution of 208 ps full-width at half-maximum (FWHM), which is much better over the analog spectrometer using the same detectors. This newly developed apparatus except for having better performance is particularly easy to be constructed and implemented.

Hui, Li; Yundong, Shao; Kai, Zhou; Jingbiao, Pang; Zhu, Wang

2011-01-01

85

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

86

Defects in electron-irradiated GaAs studied by positron lifetime spectroscopy  

SciTech Connect

A systematic study of electron-irradiation-induced defects in GaAs was carried out. The irradiation was performed at low temperature (4 K) with an incident energy of 2 MeV. Both, the defect formation and annealing behavior were studied in dependence on the fluence (10{sup 15}--10{sup 19} cm{sup {minus}2}) in undoped, n-, and p-doped GaAs. Temperature-dependent positron lifetime measurements were performed between 20 and 600 K. The thermal stability of defects was studied by annealing experiments in the temperature range of 90--600 K. A defect complex, which anneals in a main stage at 300 K, was found in all GaAs samples after electron irradiation. A possible candidate for this defect is a complex of a vacancy connected with an intrinsic defect. A second vancancylike defect was observed in n-type material after annealing at 550 K. This defect was assumed to be in the As sublattice. {copyright} {ital 1997} {ital The American Physical Society}

Polity, A.; Rudolf, F.; Nagel, C.; Eichler, S.; Krause-Rehberg, R. [Fachbereich Physik der Martin-Luther-Universitaet Halle-Wittenberg, Experimentelle Physik III, Friedemann-Bach-Platz 6, D-06108 Halle/Saale (Germany)] [Fachbereich Physik der Martin-Luther-Universitaet Halle-Wittenberg, Experimentelle Physik III, Friedemann-Bach-Platz 6, D-06108 Halle/Saale (Germany)

1997-04-01

87

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

88

On determining the entrance size of cage-like pores in mesoporous silica films by positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Pore entrance size of cage-like pores in mesoporous silica films is difficult to be determined by conventional techniques. A simple expedient is proposed by using positron annihilation lifetime spectroscopy (PALS) based on a slow positron beam. Because of the nature of positronium (Ps, the bound state of a positron and an electron) in mesoporous silica, almost no Ps annihilates in the smaller connecting channels of cages. By trimethylsilylation of the silica, an appreciable fraction of Ps can be trapped and annihilate in the channels, which renders the possibility to estimate the pore entrance size from Ps lifetime in it.

He, Chunqing; Xiong, Bangyun; Mao, Wenfeng; Kobayashi, Yoshinori; Oka, Toshitaka; Oshima, Nagayasu; Suzuki, Ryoichi

2013-12-01

89

Lifetime measurement of ATF damping ring  

SciTech Connect

The purpose of the ATF damping ring is the development of technologies for producing a low emittance beam required in future linear colliders such as JLC. The lifetime of the damping ring is very short (typically a few minutes). It is limited by elastic beam-gas scattering along with a small dynamic aperture, and by single intra-beam scattering (Touschek effect). The Touschek lifetime strongly depends upon the charge density of the beam, especially, the size of the vertical emittance. In this paper, the authors report the results of beam lifetime measurements in the ATF damping ring and the estimation of the vertical emittance from these measurements.

Okugi, T. [Tokyo Metropolitan Univ. (Japan); Hayano, H.; Kubo, K.; Naito, T.; Terunuma, N.; Urakawa, J. [High Energy Accelerator Research Organization, Tsukuba (Japan); Zimmermann, F. [Stanford Univ., CA (US). Stanford Linear Accelerator Center

1998-06-01

90

Preliminary ?c+ Lifetime Measurement from SELEX  

NASA Astrophysics Data System (ADS)

We report the results of a new ?c+ lifetime measurement from hadroproduction data taken by the SELEX (E781) experiment. Fermilab charged hyperon beam ( ?, ? and p) at 600 GeV is used to produce charm particles in Cu and diamond targets. This measurement was made using decays into the ?c+????, ?c+?pK?, and ?c+??K? modes. We used binned maximum likelihood method and 301 ± 31 events yield a lifetime of 430 ± 22 ± 9 fs.

Akgun, U.; Selex Collaboration

91

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

92

Structural studies of spinel manganite ceramics with positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

The new transition-metal manganite Cu0.1Ni0.8Co0.2Mn1.9O4 ceramics for temperature sensors with improved functional reliability are first proposed. It is established that the amount of additional NiO phase in these ceramics extracted during sintering play a decisive role. This effect is well revealed only in ceramics having a character fine-grain microstructure, while the monolithization of ceramics caused by great amount of transferred thermal energy reveals an opposite influence. The process of monolitization from the position of evolution of grain-pore structure was studied in these ceramics using positron annihilation lifetime spectroscopy.

Klym, H.; Ingram, A.; Shpotyuk, O.; Filipecki, J.; Hadzaman, I.

2011-04-01

93

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

SciTech Connect

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

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

2006-03-01

94

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

SciTech Connect

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

MacQueen, R.C.

1992-01-01

95

Measurement of the Omega0(c) lifetime  

SciTech Connect

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

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

2007-01-01

96

Measurement of the tau lifetime at SLD  

Microsoft Academic Search

A measurement of the lifetime of the tau lepton has been made using a sample of 1671 Z0-->tau+tau- 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

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

1995-01-01

97

Measurement of the tau-lepton lifetime  

SciTech Connect

We report a new and precise measurement of the lifetime of the tau lepton. The data were taken with the High Resolution Spectrometer at the SLAC e/sup +/e/sup -/ colliding-beam facility PEP operating at 29 GeV center-of-mass energy. The flight distances of 1311 tau decays to three charged particles were measured with a four-layer tubular-cell vertex chamber in conjunction with the main drift chamber. The resulting lifetime of the tau lepton is tau/sub tau/(2.99 +- 0.15 +- 0.10) x 10/sup -13/ sec.

Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J.H.; Bylsma, B.G.; Chapman, J.; Cork, B.; DeBonte, R.

1987-11-30

98

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

NASA Astrophysics Data System (ADS)

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

Ibarra, Alejandro; Lamperstorfer, Anna S.; Silk, Joseph

2014-03-01

99

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

100

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 pp¯ collisions at s = 1.8 TeV collected by the Collider Detector at Fermilab during 1992-1993. There are 76+/-8 l+D-s signal events where the Ds is identified via the decay D-s-->??-, ?-->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

101

Measurement of the Bs0 lifetime  

NASA Astrophysics Data System (ADS)

The lifetime of the Bs0 has been measured in a data sample of 8890000 hadronic events recorded with the ALEPH detector at LEP. After background subtraction 30.8 ± 6.9 events are attributed to the semileptonic decay of the Bs0 to a Ds- and an opposite-sign lepton. A maximum-likelihood fit to the distribution of the proper times of these events yields a Bs0 lifetime of ?Bs = 1.92 -0.35+0.45 ± 0.04 ps.

Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Odier, P.; Pietrzyk, B.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Gaitan, V.; Garrido, Ll.; Martinez, M.; Mattison, T.; Orteu, S.; Pacheco, A.; Padilla, C.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Marinelli, N.; Natali, S.; Nuzzo, S.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Chai, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhang, L.; Zhao, W.; Bonvicini, G.; Boudreau, J.; Casper, D.; Drevermann, H.; Forty, R. W.; Ganis, G.; Gay, C.; Girone, M.; Hagelberg, R.; Harvey, J.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lehraus, I.; Maggi, M.; Markou, C.; Mato, P.; Meinhard, H.; Minten, A.; Miquel, R.; Moser, H.-G.; Palazzi, P.; Pater, J. R.; Perlas, J. A.; Perrodo, P.; Pusztaszeri, J.-F.; Ranjard, F.; Rolandi, L.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Tomalin, I. R.; Veenhof, R.; Wachsmuth, H.; Wasserbaech, S.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Bardadin-Otwinowska, M.; Barres, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Saadi, F.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Johnson, S. D.; Møllerud, R.; Nilsson, B. S.; Kyriakis, A.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Fouque, G.; Passalacqua, L.; Rougé, A.; Rumpf, M.; Tanaka, R.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Focardi, E.; Moneta, L.; Parrini, G.; Corden, M.; Delfino, M.; Georgiopoulos, C.; Jaffe, D. E.; Levinthal, D.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Pepe-Altarelli, M.; Salomone, S.; Colrain, P.; Ten Have, I.; Knowles, I. G.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Smith, M. G.; Thompson, A. S.; Thorn, S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geweniger, C.; Graefe, G.; Hanke, P.; Hepp, V.; Karger, C.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Hassard, J. F.; Lieske, N. M.; Moutoussi, A.; Nash, J.; Patton, S.; Payne, D. G.; Phillips, M. J.; San Martin, G.; Sedgbeer, J. K.; Wright, A. G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Vogl, R.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Galla, A.; Greene, A. M.; Kleinknecht, K.; Raab, J.; Renk, B.; Sander, H.-G.; Schmidt, H.; Walther, S. M.; Wanke, R.; Wolf, B.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Drinkard, J.; Etienne, F.; Nicod, D.; Payre, P.; Ross, L.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Assmann, R.; Bauer, C.; Blum, W.; Brown, D.; Cattaneo, P.; Dehning, B.; Dietl, H.; Dydak, F.; Frank, M.; Halley, A. W.; Jakobs, K.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; Denis, R. St.; Wolf, G.; Alemany, R.; Boucrot, J.; Callot, O.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kimfn 19, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Musolino, G.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Abbaneo, D.; Bagliesi, G.; Batignani, G.; Bottigli, U.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Valassi, A.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Betteridge, A. P.; Gao, Y.; Green, M. G.; Johnson, D. L.; March, P. V.; Medcalf, T.; Mir, Ll. M.; Quazi, I. S.; Strong, J. A.; Bertin, V.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Edwards, M.; Norton, P. R.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Marx, B.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.

1994-02-01

102

Measurement of the Bs Meson Lifetime  

Microsoft Academic Search

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

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

1995-01-01

103

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+3.6±0.9)×10-13 s. The method used was to reconstruct fully the decay vertex of the channelDs??p±, ??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

104

A Precise Measurement of the Tau Lifetime  

Microsoft Academic Search

The tau lepton lifetime has been measured with the e+e- -> tau+tau- events collected by the DELPHI detector at LEP in the years 1991-1995. Three different methods have been exploited, using both one-prong and three-prong tau decay channels. Two measurements have been made using events in which both taus decay to a single charged particle. Combining these measurements gave tau_tau

J Abdallah; P Abreu; W Adam; P Adzic; T Albrecht; T Alderweireld; R Alemany-Fernandez; T Allmendinger; P P Allport; Ugo Amaldi; N Amapane; S Amato; E Anashkin; A Andreazza; S Andringa; N Anjos; P Antilogus; W D Apel; Y Arnoud; S Ask; B Åsman; J E Augustin; A Augustinus; Paul Baillon; A Ballestrero; P Bambade; R Barbier; Dimitri Yuri Bardin; G J Barker; A Baroncelli; Marco Battaglia; M Baubillier; K H Becks; M Begalli; A Behrmann; E Ben-Haim; N C Benekos; Alberto C Benvenuti; C Bérat; M Berggren; L Berntzon; D Bertrand; M Besançon; N Besson; D Bloch; M Blom; M Bluj; M Bonesini; M Boonekamp; P S L Booth; G Borisov; O Botner; B Bouquet; T J V Bowcock; I Boyko; M Bracko; R Brenner; E Brodet; P Brückman; J M Brunet; L Bugge; P Buschmann; M Calvi; T Camporesi; V Canale; F Carena; N Castro; F R Cavallo; M M Chapkin; P Charpentier; P Checchia; R Chierici; P Shlyapnikov; J Chudoba; S U Chung; K Cieslik; P Collins; R Contri; G Cosme; F Cossutti; M J Costa; D J Crennell; J Cuevas-Maestro; J D'Hondt; J Dalmau; T Da Silva; W Da Silva; G Della Ricca; A De Angelis; Wim de Boer; C De Clercq; B De Lotto; N De Maria; A De Min; L S De Paula; L Di Ciaccio; A Di Simone; K Doroba; J Drees; M Dris; G Eigen; T J C Ekelöf; M Ellert; M Elsing; M C Espirito-Santo; G K Fanourakis; D Fassouliotis; M Feindt; J Fernández; A Ferrer; F Ferro; U Flagmeyer; H Föth; E Fokitis; F Fulda-Quenzer; J A Fuster; M Gandelman; C García; P Gavillet; E N Gazis; R Gokieli; B Golob; G Gómez-Ceballos; P Gonçalves; E Graziani; G Grosdidier; K Grzelak; J Guy; C Haag; A Hallgren; K Hamacher; S Haug; F Hauler; V Hedberg; M Hennecke; H Herr; J Hoffman; S O Holmgren; P J Holt; M A Houlden; K Hultqvist; J N Jackson; G Jarlskog; P Jarry; D Jeans; E K Johansson; P D Johansson; P Jonsson; C Joram; L Jungermann; F Kapusta; S Katsanevas; E C Katsoufis; B P Kersevan; U Kerzel; A P Kiiskinen; B T King; N J Kjaer; P Kluit; P Kokkinias; C Kourkoumelis; O Kuznetsov; Z Krumshtein; M Kucharczyk; J Lamsa; G Leder; F Ledroit; L Leinonen; R Leitner; J Lemonne; V Lepeltier; T Lesiak; W Liebig; D Liko; A Lipniacka; J H Lopes; J M López; D Loukas; P Lutz; L Lyons; J MacNaughton; A Malek; S Maltezos; F Mandl; J Marco; R Marco; B Maréchal; M Margoni; J C Marin; C Mariotti; A Markou; C Martínez-Rivero; J Masik; N Mastroyiannopoulos; F Matorras; C Matteuzzi; F Mazzucato; M Mazzucato; R McNulty; C Meroni; E Migliore; W A Mitaroff; U Mjörnmark; T Moa; M Moch; K Mönig; R Monge; J Montenegro; D Moraes; S Moreno; P Morettini; U Müller; K Münich; M Mulders; L Mundim; W Murray; B Muryn; G Myatt; T Myklebust; M Nassiakou; Francesco Luigi Navarria; K Nawrocki; R Nicolaidou; M Nikolenko; A Oblakowska-Mucha; V F Obraztsov; A G Olshevskii; A Onofre; R Orava; K Österberg; A Ouraou; A Oyanguren; M Paganoni; S Paiano; J P Palacios; H Palka; T D Papadopoulou; L Pape; C Parkes; F Parodi; U Parzefall; A Passeri; O Passon; L Peralta; V F Perepelitsa; A Perrotta; A Petrolini; J Piedra; L Pieri; F Pierre; M Pimenta; E Piotto; T Podobnik; V Poireau; M E Pol; G Polok; V Pozdnyakov; N Pukhaeva; A Pullia; J Rames; A Read; P Rebecchi; J Rehn; D Reid; R Reinhardt; P B Renton; F Richard; J Rídky; M Rivero; D Rodríguez; A Romero; P Ronchese; P Roudeau; T Rovelli; V Ruhlmann-Kleider; D Ryabtchikov; A Sadovskii; L Salmi; J Salt; C Sander; A Savoy-Navarro; U Schwickerath; A Segar; R L Sekulin; M Siebel; A N Sissakian; G Smadja; O G Smirnova; A Sokolov; A Sopczak; R Sosnowski; Tz Spassoff; M Stanitzki; A Stocchi; J Strauss; B Stugu; M Szczekowski; M Szeptycka; T Szumlak; T Tabarelli de Fatis; A C Taffard; F Tegenfeldt; J Timmermans; L G Tkatchev; M Tobin; S Todorovova; B Tomé; A Tonazzo; P Tortosa; P Travnicek; D Treille; G Tristram; M Trochimczuk; C Troncon; M L Turluer; I A Tyapkin; P Tyapkin; S Tzamarias; V Uvarov; G Valenti; P van Dam; J Van Eldik; A Van Lysebetten; N Van Remortel; I Van Vulpen; G Vegni; F Veloso; W A Venus; P Verdier; V Verzi; D Vilanova; L Vitale; V Vrba; H Wahlen; A J Washbrook; C Weiser; D Wicke; J H Wickens; G Wilkinson; M Winter; M Witek; O P Yushchenko; A Zalewska-Bak; P Zalewski; D Zavrtanik; V Zhuravlov; N I Zimin; A Zintchenko; M Zupan

2003-01-01

105

B-lifetime measurements at the tevatron  

SciTech Connect

During the run period from May 1992 to begin of June 1993 the Collider Detector at Fermilab (CDF) has recorded {approx} 21.4 pb{sup {minus}1} of p{anti p} collider data at {radical}s = 1.8 TeV. For this run the detector had been upgraded which significantly enhanced its b-physics capabilities. The upgrades include a high precision Silicon VerteX detector (SVX) which enables CDF to reconstruct the decay vertex and decay length of b-hadrons. In this article the author reports on several measurements of the lifetime of b-flavored hadrons. The determination of the average b-lifetime using inclusive J/{psi}`s, the measurement of the B{sup {+-}} and B{sup 0} lifetimes by reconstructing exclusive final states including a J/{psi} or {psi}(2S) and a measurement of the B{sub s}{sup 0} meson lifetime exploiting the decay: B{sub s} {yields} l{nu}D{sub s}{sup +} {yields} l{nu}{phi}{pi}{sup +} {yields} l{nu}K{sup +}K{sup {minus}}{pi}{sup +}.

Wenzel, H. [Fermi National Accelerator Lab., Batavia, IL (United States)]|[INFN, Pisa (Italy); CDF Collaboration

1993-11-01

106

Fluorescence lifetime measurements in flow cytometry  

NASA Astrophysics Data System (ADS)

Fluorescence lifetime measurements provide insights int eh dynamic and structural properties of dyes and their micro- environment. The implementation of fluorescence lifetime measurements in flow cytometric systems allows to monitor large cell and particle populations with high statistical significance. In our system, a modulated laser beam is used for excitation and the phase shift of the fluorescence signal recorded with a fast computer controlled digital oscilloscope is processed digitally to determine the phase shift with respect to a reference beam by fast fourier transform. Total fluorescence intensity as well as other parameters can be determined simultaneously from the same fluorescence signal. We use the epi-illumination design to allow the use of high numerical apertures to collect as much light as possible to ensure detection of even weak fluorescence. Data storage and processing is done comparable to slit-scan flow cytometric data using data analysis system. The results are stored, displayed, combined with other parameters and analyzed as normal listmode data. In our report we discuss carefully the signal to noise ratio for analog and digital processed lifetime signals to evaluate the theoretical minimum fluorescence intensity for lifetime measurements. Applications to be presented include DNA staining, parameters of cell functions as well as different applications in non-mammalian cells such as algae.

Beisker, Wolfgang; Klocke, Axel

1997-05-01

107

Porous glasses as a matrix for incorporation of photonic materials. Pore determination by positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

Porous glasses prepared by the sol-gel technique have a variety of applications when incorporated by photonic materials: tunable lasers, sensors, luminescence solar concentrators, semiconductor quantum dots, biological markers. The known methods of pore size determinations, the nitrogen adsorption and mercury porosimetry allow to determine the sizes of open pores. Positron annihilation lifetime spectroscopy (PALS) allows to determine pore sizes also of closed pores. As an example we have performed measurements of non-doped zirconia-silica-polyurethane (ZSUR) ormocer glasses and the same glasses doped with lead sulfide quantum dots. The pore radii range between 0.25-0.38 nm, total surface area 15.5-23.8 m 2/g.

Reisfeld, Pore determination by positron annihilation lifetime spectroscopy R.; Saraidarov, T.; Jasinska, B.

2004-07-01

108

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

PubMed

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

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

2013-08-01

109

Measurement of the tau lepton lifetime  

Microsoft Academic Search

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

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

1991-01-01

110

Measurement of the Ï lifetime at SLD  

Microsoft Academic Search

A measurement of the lifetime of the Ï lepton has been made using a sample of 1671 {ital Z}°âÏ{sup +}Ï⁻ 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

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

1995-01-01

111

A measurement of the tau lifetime  

Microsoft Academic Search

The tau lepton lifetime is measured using four different methods with the DELPHI detector. Three measurements using one prong decays are combined, accounting for correlations, resulting in tautau=298 +\\/-7 (stat.)+\\/-4 (syst.) fs while the decay length distribution of three prong decays gives pipi=298+\\/-13 (stat)+\\/-(syst.) fs. The combined result is tautau=298+\\/-7 fs. The ratio of the Fermi coupling constant from tau

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

1993-01-01

112

Measurement of the BS0 lifetime  

Microsoft Academic Search

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

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

1993-01-01

113

Measurement of the ? lifetime at SLD  

NASA Astrophysics Data System (ADS)

A measurement of the lifetime of the ? lepton has been made using a sample of 1671 Z0-->?+?- 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 ??=297+/-9 (stat)+/-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.; Daoudi, M.; de Sangro, R.; de Simone, P.; dell'orso, R.; Dima, M.; Du, P. Y.; 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.; 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.; Müller, 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.; Saxton, O. H.; Schaffner, S. F.; Schalk, T.; Schindler, R. H.; Schneekloth, U.; Schumm, B. A.; Seiden, A.; Sen, S.; Serbo, V. V.; Shaevitz, M. H.; Shank, J. T.; Shapiro, G.; Shapiro, S. L.; Sherden, D. J.; Shmakov, K. D.; Simopoulos, C.; Sinev, N. B.; Smith, S. R.; Snyder, J. A.; Stamer, P.; Steiner, H.; Steiner, R.; Strauss, M. G.; Su, D.; Suekane, F.; Sugiyama, A.; Suzuki, S.; Swartz, M.; Szumilo, A.; Takahashi, T.; Taylor, F. E.; Torrence, E.; Turk, J. D.; Usher, T.; Va'vra, J.; Vannini, C.; Vella, E.; Venuti, J. P.; Verdier, R.; Verdini, P. G.; Wagner, S. R.; Waite, A. P.; Watts, S. J.; Weidemann, A. W.; Weiss, E. R.; Whitaker, J. S.; White, S. L.; Wickens, F. J.; Williams, D. A.; Williams, D. C.; Williams, S. H.; Willocq, S.; Wilson, R. J.; Wisniewski, W. J.; Woods, M.; Word, G. B.; Wyss, J.; Yamamoto, R. K.; Yamartino, J. M.; Yang, X.; Yellin, S. J.; Young, C. C.; Yuta, H.; Zapalac, G.; Zdarko, R. W.; Zeitlin, C.; Zhang, Z.; Zhou, J.

1995-11-01

114

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

115

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

116

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  

NASA Astrophysics Data System (ADS)

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 annealing out of vacancy clusters after low-temperature electron irradiation, as well as recovery and recrystallization of a tungsten sheet, in as-manufactured form. Making measurements on uncompacted powder, we find an increasing fraction of positrons annihilating in surface states with decreasing powder-particle size. The powder-particle and grain sizes (influencing the x-ray domain size) are monitored additionally by means of metallography and x-ray diffraction. We find that all of the methods give results in agreement with each other. The small grain sizes at lower temperature, about one fifth of the powder-particle size, cause positrons to annihilate at grain boundaries, leading to vacancy-cluster-like signals. At the intensive-shrinkage stage, there are certainly contributions from different shrinkage mechanisms. The observed shrinkage rates can be explained by Coble creep. It is possible that dislocations also play a role as vacancy sources and sinks, since the intensive-shrinkage stage occurs in a temperature region wherein recrystallization takes place.

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

1999-02-01

117

Formation porosity measurement using epithermal neutron lifetime  

Microsoft Academic Search

A logging tool for in-situ measurement of earth formation porosity using epithermal neutron lifetime has been constructed and tested. A 14-MeV neutron generator in the tool emits pulses of neutrons and a Gd-covered ³He counter detects neutrons returning from the formation as a function of time following the emission pulse. Counts are accumulated in 200 1-..mu..s-wide channels for repeated pulses

D. C. Stromswold; W. R. Mills; R. D. Wilson; T. K. Cook

1989-01-01

118

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 ± 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

119

Positron annihilation lifetime and Doppler broadening study in 50 MeV Li 3+ ion irradiated polystyrene films  

NASA Astrophysics Data System (ADS)

Swift heavy ion (SHI) irradiation of polymeric materials results in the change of their free volume properties which have strong correlation with their macroscopic properties. The modification depends on the polymer and ion beam parameters, namely ion energy, fluence and ion species. Polystyrene films were irradiated with Li 3+ ions of energy 50 MeV from 15 UD Pelletron accelerators at Inter University Accelerator Centre (IUAC), New Delhi, India to the fluences of 10 11, 10 12 and 10 13 ions/cm 2. Nanosized free volume parameters in the polymer have been studied by positron annihilation lifetime spectroscopy (PALS) and Doppler broadening spectroscopy (DBS). From o-Ps lifetime ?3, free volume hole radius, mean free volume of microvoids and fractional free volume are computed and modification in free volume with the fluence is studied. Free volume parameters change slowly with ion fluence with a decrease at the highest fluence of 10 13 ions/cm 2. The decrease in ?3 and I3 (reflecting the number of free volume holes) may be interpreted on the process of cross-linking. S parameter obtained from DBS measurements showed a minor decrease with increasing fluence.

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

2010-06-01

120

A measurement of the ?0b lifetime  

NASA Astrophysics Data System (ADS)

The lifetime of the ?b0 baryon has been measured using 3.6 million hadronic Z 0 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 ± 13 ?c+? - combinations attributed to ?b0 decays in this data sample, we measure ?( ?b0) = 1.14 -0.19+0.22 ± 0.07 ps, where the errors are statistical and systematic, respectively.

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

1995-02-01

121

A measurement of the tau lifetime  

NASA Astrophysics Data System (ADS)

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

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

1993-03-01

122

Positron-annihilation-lifetime response and broadband dielectric relaxation spectroscopy: Diethyl phthalate  

NASA Astrophysics Data System (ADS)

We report the results of a combined phenomenological analysis of the data from positron-annihilation-lifetime spectroscopy (PALS) and the relaxation data from broadband dielectric spectroscopy (BDS) on diethyl phthalate (DEP). The ortho-positronium ( o -Ps) lifetime, ?3 , as a function of temperature over a temperature range from 67K up to 300K is compared with the spectral features and the relaxation parameters of the BDS spectra decomposed into the primary ? and the secondary ? processes in the temperature range from 140K up to 380K by using the Williams-Watts scheme. Phenomenological model-free analysis of the ?3-T plot provides the three characteristic PALS temperatures, where the two most pronounced ones at TgPALS=185K and Tb2=245K=1.32TgPALS are related to the glass-liquid transition and the onset of a quasiplateau region, respectively. In the case of a weaker bend effect at Tb1=210K=1.14TgPALS , a number of new coincidences with changes in the dielectric ? process have been found. They concern the changes in width parameter of the distribution function for the ? relaxation time and the activation energy of the ?eff process, a crossover from the Arrhenius to the non-Arrhenius type of temperature dependence as well as with the onset of a short-time tail of the ? relaxation time distribution and finally, with changes in the relaxation strength of the ? and ?eff processes. All these findings indicate a close connection of the o -Ps annihilation parameters and relaxation characteristics of BDS response for the DEP matrix.

Bartoš, J.; Alegría, A.; Šauša, O.; Tyagi, M.; Gómez, D.; Krištiak, J.; Colmenero, J.

2007-09-01

123

Analysis of positron annihilation lifetime data by numerical Laplace inversion: Corrections for source terms and zero-time shift errors  

NASA Astrophysics Data System (ADS)

We have recently described modifications to the program CONTIN [S.W. Provencher, Comput. Phys. Commun. 27 (1982) 229] for the solution of Fredholm integral equations with convoluted kernels of the type that occur in the analysis of positron annihilation lifetime data [R.B. Gregory and Yongkang Zhu, Nucl. Instr. and Meth. A290 (1990) 172]. In this article, modifications to the program to correct for source terms in the sample and reference decay curves and for shifts in the position of the zero-time channel of the sample and reference data are described. Unwanted source components, expressed as a discrete sum of exponentials, may be removed from both the sample and reference data by modification of the sample data alone, without the need for direct knowledge of the instrument resolution function. Shifts in the position of the zero-time channel of up to half the channel width of the multichannel analyzer can be corrected. Analyses of computer-simulated test data indicate that the quality of the reconstructed annihilation rate probability density functions is improved by employing a reference material with a short lifetime and indicate that reference materials which generate free positrons by quenching positronium formation (i.e. strong oxidizing agents) have lifetimes that are too long (400-450 ps) to provide reliable estimates of the lifetime parameters for the shortlived components with the methods described here. Well-annealed single crystals of metals with lifetimes less than 200 ps, such as molybdenum (123 ps) and aluminum (166 ps) do not introduce significant errors in estimates of the lifetime parameters and are to be preferred as reference materials. The performance of our modified version of CONTIN is illustrated by application to positron annihilation in polytetrafluoroethylene.

Gregory, Roger B.

1991-05-01

124

Plunger Lifetime Measurements in 102Pd  

SciTech Connect

Recently, an intense experimental effort has been devoted to the search of empirical proofs of critical-point symmetries in nuclear structure. These symmetries describe shape-phase transitions and provide parameter-free predictions (up to over-all scale factors) for excitation spectra and B(E2) values. This contribution reports on recent plunger-lifetime measurements ON 102Pd carried out at LNL, Legnaro, with the Cologne plunger apparatus coupled to the GASP spectrometer and using the 92Zr(13C,3n)102Pd reaction at 48 MeV. According to the results of our measurements, 102Pd is so far the best known paradigm of the E(5) critical-point symmetry.

Kalyva, G.; Spyrou, A.; Axiotis, M.; Harissopulos, S. [Institute of Nuclear Physics, NCSR 'Demokritos', 153.10 Aghia Paraskevi, Athens (Greece); Dewald, A.; Fitzler, A.; Saha, B.; Liennemann, A. [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicherstr. 77, 50937 Cologne (Germany); Vlastou, R. [National Technical University of Athens, Zographou Campus, 15780 Athens (Greece); Napoli, D. R.; Marginean, N.; Rusu, C.; De Angelis, G. [INFN, Laboratori Nationali di Legnaro, Legnaro (Italy); Ur, C.; Bazzacco, D.; Farnea, E. [Dipartimento di Fisica dell' Universita, Padova (Italy); INFN, Sezioni di Padova, Padova (Italy); Balabanski, D. L. [Dipartimento di Fisica Universita degli Studi di Camerino, Camerino (Italy); Julin, R. [Department of Physics, University of Jyvaeskylae, POB 35, 40014 Jyvaeskylae (Finland)

2006-04-26

125

First measurement of the lifetime of the ? c0  

NASA Astrophysics Data System (ADS)

We present the first measurement of the lifetime of the ? c0 baryon. The data were collected in the Fermilab high energy photoproduction experiment E687. The measured lifetime is ? = 86 -20+27(stat.) ± 28(syst.) fr. Thus the ? c0 has one of the shorter lifetimes among the weakly decaying singly charmed baryons.

Frabetti, P. L.; Cheung, H. W. K.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Greene, S. V.; Johns, W. E.; Nehring, M. S.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garbincius, P. H.; Garren, L.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Vittone, M.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Culbertson, R.; Gardner, R. W.; Greene, R.; Wiss, J.; Alimonti, G.; Bellini, G.; Boschini, M.; Brambilla, D.; Caccianiga, B.; Cinquini, L.; Di Corato, M.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Moroni, L.; Pedrini, D.; Perasso, L.; Prelz, F.; Sala, A.; Sala, S.; Torretta, D.; Buchholz, D.; Claes, D.; Gobbi, B.; O'Reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Puseljic, D. L.; Ruchti, R. C.; Shephard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Castoldi, C.; Gianini, G.; Ratti, S. P.; Riccardi, C.; Viola, L.; Vitulo, P.; Lopez, A.; Grim, G. P.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Sheldon, P. D.; Davenport, F.; Blackett, G. R.; Danyo, K.; Pisharody, M.; Handler, T.; Cheon, B. G.; Kang, J. S.; Kim, K. Y.; E687 Collaboration

1995-02-01

126

Precise Lifetime Measurement of ^37K  

NASA Astrophysics Data System (ADS)

To determine the correlation parameters of the ? decay of transitions between isobaric analogue states, the ft value is needed to determine ?, the ratio of Gamow-Teller to Fermi matrix elements. A recent review of all T = 12 ? mirror decays [1] indicates that ^37K is one of the best candidates for testing the Standard Model. The ft value is currently limited by the 0.6% uncertainty in the lifetime. In order to make Standard Model predictions of the correlation parameters negligible compared to planned experiments, we have performed a precision lifetime measurement of ^37K. We used the MARS separator for producing a secondary beam of ^37K with a purity of 98.5%. We implanted the activity in an aluminized-Mylar tape that, as part of a fast-tape drive system, quickly transported the sample to a well shielded location, stopping it in the centre of a 4? proportional gas counter. The recorded data was separated into 25 runs, each characterized by a different combination of detector high voltages, discriminator thresholds and dominant dead-time settings. An overview of the experiment and results will be presented. [4pt] [1] O. Naviliat-Cuncic and N. Severijns, Phys. Rev. Lett. 102, 142302 (2009)

Shidling, P. D.; Behling, R. S.; Hardy, J. C.; Iacob, V. E.; Mehlman, M.; Melconian, D.; Roeder, B. T.; Stephens, H.

2011-04-01

127

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

Microsoft Academic Search

Focused ion beam (FIB) microscopy was used to obtain the time dependent transformation fraction and positron annihilation lifetime spectroscopy (PALS) was employed to analyze the vacancy-type defects in electroplated copper (Cu) during room-temperature microstructrual evolution. It was found that PALS is more sensitive than FIB to show the room-temperature microstructual evolution of electroplated Cu at the first stage of self-annealing.

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

2008-01-01

128

Detection of atomic scale changes in the free volume void size of three-dimensional colorectal cancer cell culture using positron annihilation lifetime spectroscopy.  

PubMed

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

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

2014-01-01

129

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

PubMed Central

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

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

2014-01-01

130

Effect of interfacial interaction on free volumes in phenol-formaldehyde resin-carbon nanotube composites: positron annihilation lifetime and age momentum correlation studies.  

PubMed

The phenol-formaldehyde-carbon nanotube composites were characterized for their free volume properties and interfacial interactions between nanotubes and the polymer matrix. The base polymeric material was a novolac type phenol-formaldehyde (PF) condensation resin cross-linked with para-toluene sulfonic acid. Multi-wall carbon nanotubes (MWCNTs) were synthesized using a catalytical chemical vapor deposition method and characterized using high-resolution transmission electron microscopy. The PF resin-carbon nanotubes composites having 2, 5, 10 and 20% (w/w%) MWCNTs were prepared. The crystallinity and morphology of the samples were characterized using X-ray diffraction and scanning electron microscopy. The free volume size in the polymer nanocomposites was observed to increase with the increase in nanotube content. Positron age momentum correlation (AMOC) studies revealed the electronic environment around different positron annihilation sites. The studies showed that ortho-positronium principally annihilates from interfacial regions of polymer and nanotubes in the nanocomposite. The positron lifetime studies together with AMOC measurements indicate an increase in the free volumes at the interface of polymer and MWCNTs in the composite. The free positron intensities showed that the polymer and nanotubes are weakly interacting in this system. PMID:22688656

Sharma, S K; Prakash, J; Sudarshan, K; Maheshwari, P; Sathiyamoorthy, D; Pujari, P K

2012-08-21

131

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

132

Hydrogen indium vacancy complex V InH 4 in n-type InP studied by positron-lifetime  

Microsoft Academic Search

Positron-lifetime experiments have been carried out on two undoped n-type liquid encapsulated Czochralski (LEC)-grown InP samples with different stoichiometric compositions in the temperature range 10–300K. For temperatures below 120K for P-rich InP and 100K for In-rich InP, the positron average lifetime began to increase rapidly and then leveled off, which was associated with the charge state change of hydrogen indium

W. D. Mao; S. J. Wang; Z. Wang; N. F. Sun; T. N. Sun; Y. W. Zhao; H. Z. Wang

2005-01-01

133

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

134

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

135

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

Microsoft Academic Search

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

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

1999-01-01

136

The influence of microstructure on the sintering process in crystalline metal powders investigated by positron lifetime spectroscopy: I. Electrolytic and spherical copper powders  

Microsoft Academic Search

We investigate the influence of microstructure (dislocations, and grain and subgrain boundaries) on the sintering process in compacts of electrolytic and spherical copper powders by means of positron lifetime spectroscopy. We compare the lifetime data obtained to the kinetics of the annealing out of vacancy clusters after low-temperature electron irradiation, and the kinetics of recovery and recrystallization after plastic deformation.

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

1999-01-01

137

Lifetime measurement of high spin states in (75) Kr  

SciTech Connect

The lifetimes of high spin states of {sup 75}Kr have been determined via {sup 50}Cr ({sup 28}Si, 2pn) {sup 75}Kr reaction in positive parity band using the Doppler-shift attenuation method. The transition quadrupole moments Q deduced from lifetime measurements have been compared with {sup 75}Br. Experimental results obtained from lifetime measurement are interpreted in the framework of projected shell model.

Sheikh, Javid [ORNL; Trivedi, T. [University Allahabad, Uttar Pradesh, India; Maurya, K. [University Allahabad, Uttar Pradesh, India; Mehrotra, I. [University Allahabad, Uttar Pradesh, India; Palit, R. [Tata Inst Fundamental Res, Bombay, Maharashtra, India; Naik, Z. [Tata Inst Fundamental Res, Bombay, Maharashtra, India; Jain, H. C. [Tata Inst Fundamental Res, Bombay, Maharashtra, India; Negi, D. [Inter Univ Accelerator Ctr, New Delhi, India; Mahanto, G. [Inter Univ Accelerator Ctr, New Delhi, India; Kumar, R. [Inter Univ Accelerator Ctr, New Delhi, India; Singh, R.P. [Inter Univ Accelerator Ctr, New Delhi, India; Muralithar, S. [Inter Univ Accelerator Ctr, New Delhi, India; Pancholi, S.C. [Inter Univ Accelerator Ctr, New Delhi, India; Bhowmik, R.K. [Inter Univ Accelerator Ctr, New Delhi, India; Yang, Y-C [Shanghai Jiao Tong University, Shanghai; Sun, Y. [Shanghai Jiao Tong University, Shanghai; Dahl, A. [Banaras Hindu Univ, Varanasi Uttar Pradesh, India; Raju, M.K. [Andhra Univ, Waltair, Andhra Pradesh, India; Appannababu, S. [Maharaja Sayajirao Univ Baroda, Gujarat, India; Kumar, S. [University of Delhi, New Delhi, India; Choudhury, D. [Indian Inst Technol Roorkee, Uttar Pradesh, India; Jain, A. K. [Indian Inst Technol Roorkee, Uttar Pradesh, India

2010-01-01

138

Infrared, Raman, 1H NMR, thermal and positron annihilation lifetime studies of Pb(II), Sn(II), Sb(III), Bi(III)-barbital complexes  

NASA Astrophysics Data System (ADS)

Metal complexes of Pb(II), Sn(II), Sb(III) and Bi(III) with a barbital sodium were synthesized and characterized by several techniques, including elemental analysis (C, H and N), molar conductance measurements, infrared, Raman, 1H NMR, positron annihilation lifetime and thermogravimetric analysis. Reactions of barbital sodium (NaL) with salts of Pb(NO3)2, SnCl2?2H2O, SbCl3 and BiCl3 affords four novel mononuclear complexes [Pb(HL)2], [Sn(L)(H2O)], [Sb(HL)(L)] and [Bi(HL)(L)]. In complexes of Pb(II), Sb(III) and Bi(III), the molar ratio of metal-to-ligand is 1:2. Both of Sb(III) and Bi(III) complexes have six coordination via two molecules of barbital (HL and L), one of them deprotonated NH. The Pb(II) complex has a central metal ion adopts tetradentate fashion which surrounded by two (HL) barbital moieties. The elemental analysis shows that Sn(II) complex is tetradentate 1:1 ratio, chelated through oxygen sbnd O of (ONa), deprotonated (sbnd NH) and one coordinated water molecule. The positron annihilation lifetime parameters were found to be dependent on the structure, electronic configuration and molecular weight of metal complexes.

Refat, Moamen S.; Sharshar, T.

2012-05-01

139

Improved measurement of the lifetime of the ? lepton  

NASA Astrophysics Data System (ADS)

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

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

1996-02-01

140

Measured minority-carrier lifetime and CIGS device performance  

Microsoft Academic Search

The relationship between lifetime measured by time-resolved photoluminescence on bare CIGS films and subsequent device performance is examined. A correlation between device voltage and lifetime is demonstrated. The effects of measured band gap and carrier density are discussed. Results are compared with fundamental calculations.

Ingrid L. Repins; Wyatt K. Metzger; Craig L. Perkins; Jian V. Li; Miguel A. Contreras

2009-01-01

141

Method for the measurement of positron affinities and positron work functions suitable for both positive and negative work function materials  

NASA Astrophysics Data System (ADS)

The positron affinity A+, defined by A+ + ?- + ?+ = 0, where ?- ( ?+) refer to the electron (positron) work functions, is a fundamental property of solids which is useful for the determination of the behavior of positrons in multicomponent systems. For systems with a negative positron work function it is often possible to estimate the positron work function and affinity by measuring the energy of positrons re-emitted from the surface. However, this method will not work in those cases for which the positron work function is positive. While the positron affinity may, in principle, be determined in these cases from positronium time-of-flight measurements, such measurements are technically difficult. In this paper, a new method for the determination of positron affinities and positron work functions will be outlined. This method, which is based upon measurements of the cut-off energy in positron-induced secondary electron spectra, is of particular interest in that it may be used in cases where the positron work function is positive.

Weiss, Alex H.; Yang, S.; Zhou, H. Q.; Jung, E.; Koymen, A. R.; Naidu, S.; Brauer, Gerhard; Puska, Martti J.

1995-01-01

142

An internal quantum counter for lifetime measurements  

NASA Astrophysics Data System (ADS)

Excitation power thresholds and avalanche processes have been investigated on two infrared metastable levels of Nd-doped CeCl 3. An internal quantum counter effect obtained with a single laser radiation is shown to be responsible for the avalanche and is used in order to estimate the lifetimes of the two infrared levels.

Pelletier-Allard, N.; Pelletier, R.

1991-02-01

143

Positron annihilation studies of moisture in graphite-reinforced composites  

NASA Technical Reports Server (NTRS)

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

Singh, J. J.; Holt, W. H.; Mock, W., Jr.; Buckingham, R. D.

1980-01-01

144

Measurement of positron work function, positron re-emission, positronium fraction and PAES intensities from 6H-SiC  

NASA Astrophysics Data System (ADS)

The positron work function of single crystal 6H-SiC was experimentally determined from an energy analysis of positrons re-emitted when the surface was bombarded with keV energy positrons. SiC has a negative positron work function and re-emits a significant fraction of the incident keV positrons in a narrow energy range of work function energy to a few eV. This suggests the use of SiC as a new material for positron moderators used in the production of monoenergetic positron beams. The re-emitted positron yield was determined from measurement of the number of annihilations near the sample as a grid bias is varied to selectively allow positrons to leave the view of the gamma detector. The positron yield and re-emission rate were found to be dependent on the beam energy, temperature and especially on the surface conditions produced by ion sputtering and subsequent annealing. The positron diffusion length in the virgin material was calculated and the surface conditions for optimum re-emission were determined. Positronium formation at the surface and the existence of a stable positron surface state as demonstrated by the observation of the Si L2,3VV positron Auger line will also be discussed.

Nangia, Amit; Kim, Jaehong; Weiss, Alex; Brauer, Gerhard

1997-03-01

145

Measurement of the lifetime of the ?0c  

NASA Astrophysics Data System (ADS)

A measurement of the lifetime of the charmed strange baryon ?0c is presented. The data were accumulated by the Fermilab high energy photoproduction experiment E687. The measurement has been made using 42+/-10 ?0c-->?-?+ decays. The lifetime of the ?0c is measured to be 0.101+0.025-0.017+/-0.005 ps and its mass is measured to be 2462.1+/-3.1+/-1.4 MeV/c2.

Frabetti, P. L.; Cheung, H. W.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Greene, S. V.; Johns, W. E.; Nehring, M. S.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garren, L.; Garbincius, P. H.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Culbertson, R.; Gardner, R. W.; Greene, R.; Wiss, J.; Alimonti, G.; Bellini, G.; Caccianiga, B.; Cinquini, L.; di Corato, M.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Moroni, L.; Pedrini, D.; Perasso, L.; Sala, A.; Sala, S.; Torreta, D.; Vittone, M.; Buchholz, D.; Claes, D.; Gobbi, B.; O'reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Pušelji?, D. L.; Ruchti, R. C.; Shepard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Castoldi, C.; Diaferia, R.; Gianini, G.; Ratti, S. P.; Riccardi, C.; Vitulo, P.; Lopez, A.; Grim, G. P.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Sheldon, P. D.; Davenport, F.; Filasetta, J. F.; Blackett, G. R.; Pisharody, M.; Handler, T.; Cheon, B. G.; Kang, J. S.; Kim, K. Y.

1993-04-01

146

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

147

A measurement of the lifetime of the tau lepton  

Microsoft Academic Search

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

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

1991-01-01

148

Polymeric membrane studied using slow positron beam  

Microsoft Academic Search

A radioisotope slow positron beam has been built at the Chung Yuan Christian University in Taiwan for the research and development in membrane science and technology. Doppler broadening energy spectra and positron annihilation lifetime have been measured as a function of positron energy up to 30keV in a polyamide membrane prepared by the interfacial polymerization between triethylenetetraamine (TETA) and trimesoyl

Wei-Song Hung; Chia-Hao Lo; Mei-Ling Cheng; Hongmin Chen; Guang Liu; Lakshmi Chakka; D. Nanda; Kuo-Lun Tung; Shu-Hsien Huang; Kueir-Rarn Lee; Juin-Yih Lai; Yi-Ming Sun; Chang-Cheng Yu; Renwu Zhang; Y. C. Jean

2008-01-01

149

Free volume and phase transitions of 1-butyl-3-methylimidazolium based ionic liquids from positron lifetime spectroscopy.  

PubMed

Positron annihilation lifetime spectroscopy (PALS) was used to study a series of ionic liquids (ILs) with the 1-butyl-3-methylimidazolium cation ([C(4)MIM](+)) but different anions [Cl](-), [BF(4)](-), [PF(6)](-), [OTf](-), [NTf(2)](-), and [B(hfip)(4)](-) with increasing anion volumes. Changes of the ortho-positronium (o-Ps) lifetime parameters with temperature were observed for crystalline and amorphous (glass, supercooled, and normal liquid) states. Evidence for distinct phase transitions, e.g. melting, crystallization and solid-solid transitions, was observed in several PALS experiments. The o-Ps mean lifetime ??(3)? showed smaller values in the crystalline phase due to dense packing of the material compared to the amorphous phase. The o-Ps lifetime intensity I(3) in the liquid state is clearly smaller than in the crystallized state. This behaviour can be attributed to a solvation of e(+) by the anions, which reduces the Ps formation probability in the normal and supercooled liquid. These phenomena were observed for the first time when applying the PALS technique to ionic liquids by us in one preliminary and in this work. Four of the ionic liquids investigated in this work ([BF(4)](-), [NTf(2)](-), [PF(6)](-) and [Cl](-) ILs) exhibit supercooled phases. The specific hole densities and occupied volumes of those ILs were obtained by comparing the local free volume with the specific volume from pressure-volume-temperature (PVT) experiments. From the o-Ps lifetime, the mean size ?v(h)? of free volume holes of the four samples was calculated and compared with that calculated according to Fürth's hole theory. The hole volumes from both methods agree well. From the Cohen-Turnbull fitting of viscosity and conductivity against PALS/PVT results, the influence of the free volume on molecular transport properties was investigated. PMID:22472912

Yu, Yang; Beichel, Witali; Dlubek, Günter; Krause-Rehberg, Reinhard; Paluch, Marian; Pionteck, Jürgen; Pfefferkorn, Dirk; Bulut, Safak; Friedrich, Christian; Pogodina, Natalia; Krossing, Ingo

2012-04-01

150

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

151

Measurement of the Bs0 Lifetime Using Semileptonic Decays  

Microsoft Academic Search

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

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

2006-01-01

152

Tau and B lifetime measurements from the MARK II  

SciTech Connect

Measurement of the tau lifetime checks whether the tau couples to the charged weak current with the same universal coupling strength as the e and ..mu... The lifetime of bottom hadrons measures the weak coupling between the bottom quark and the charm and up quarks. Measurements of these lifetimes have been made with the MARK II detector at the e/sup +/e/sup -/ storage ring PEP at 29.0 GeV center-of-mass energy at the Stanford Linear Accelerator Center.

Hanson, G.G.

1983-08-01

153

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

NASA Astrophysics Data System (ADS)

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

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

2008-09-01

154

Neutron lifetime measurements using gravitationally trapped ultracold neutrons  

SciTech Connect

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

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

2008-09-15

155

Precision measurement of the positive muon lifetime by the MuLan collaboration  

NASA Astrophysics Data System (ADS)

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

Tishchenko, V.; MuLan Collaboration

2012-04-01

156

Measurement of the mass and lifetime of the ?+c  

NASA Astrophysics Data System (ADS)

Measurements of the mass and lifetime of the ?+c decaying into ?-?+?+ are presented. The data were accumulated by the Fermilab high-energy photoproduction experiment E687. The mass of the ?+c is measured to be 2464.4+/-2.0+/-1.4 MeV/c2 and the lifetime is measured to be 0.41+0.11-0.08+/-0.02 ps.

Frabetti, P. L.; Cheung, H. W.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Greene, S. V.; Johns, W. E.; Nehring, M. S.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garren, L.; Garbincius, P. H.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Culbertson, R.; Gardner, R. W.; Greene, R.; Wiss, J.; Alimonti, G.; Bellini, G.; Caccianiga, B.; Cinquini, L.; di Corato, M.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Moroni, L.; Pedrini, D.; Perasso, L.; Sala, A.; Sala, S.; Torretta, D.; Vittone, M.; Buchholz, D.; Claes, D.; Gobbi, B.; O'reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Pušelji?, D. L.; Ruchti, R. C.; Shephard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Castoldi, C.; Diaferia, R.; Gianini, G.; Ratti, S. P.; Riccardi, C.; Vitulo, P.; Lopez, A.; Grim, G. P.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Sheldon, P. D.; Davenport, F.; Filasetta, J. F.; Blackett, G. R.; Pisharody, M.; Handler, T.; Cheon, B. G.; Kang, J. S.; Kim, K. Y.

1993-03-01

157

Precise measurement of the D+/-s meson lifetime  

NASA Astrophysics Data System (ADS)

A precise measurement of the D+/-s meson lifetime is reported. The data were accumulated by the high energy photoproduction experiment E687 at Fermilab in the 1990-1991 fixed target run. The measurement has been done using 900 fully reconstructed D+/-s-->??+/- decays. The lifetime of the D+/-s meson is measured to be 0.475+/-0.020+/-0.007 ps.

Frabetti, P. L.; Cheung, H. W.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Greene, S. V.; Johns, W. E.; Nehring, M. S.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garbincius, P. H.; Garren, L.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Culbertson, R.; Gardner, R. W.; Greene, R.; Wiss, J.; Alimonti, G.; Bellini, G.; Caccianiga, B.; Cinquini, L.; di Corato, M.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Moroni, L.; Pedrini, D.; Perasso, L.; Sala, A.; Sala, S.; Torretta, D.; Vittone, M.; Buchholz, D.; Claes, D.; Gobbi, B.; O'reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Pušelji?, D. L.; Ruchti, R. C.; Shephard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Castoldi, C.; Diaferia, R.; Gianini, G.; Ratti, S. P.; Riccardi, C.; Vitulo, P.; Lopez, A.; Grim, G. P.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Sheldon, P. D.; Davenport, F.; Filasetta, J. F.; Blackett, G. R.; Pisharody, M.; Handler, T.; Cheon, B. G.; Kang, J. S.; Kim, K. Y.

1993-08-01

158

Precise measurements of the D0 and D+ meson lifetimes  

NASA Astrophysics Data System (ADS)

We report precise measurements of the D0 and D+ meson lifetimes by the E687 Collaboration at Fermilab. The measurements have been made using 16000 fully reconstructed decays of the D0 into the K-?+ and K-?+?-?+ final states and 9000 decays of the D+ into the K-?+?+ final state. The lifetimes of the D0 and D+ mesons are measured to be 0.413±0.004±0.003 ps and 1.048±0.015±01011 ps respectively.

Frabetti, P. L.; Cheung, H. W. K.; Cumalat, J. P.; Dallapiccola, C.; Ginkel, J. F.; Greene, S. V.; Johns, W. E.; Nehring, M. S.; Butler, J. N.; Cihangir, S.; Gaines, I.; Garbincius, P. H.; Garren, L.; Gourlay, S. A.; Harding, D. J.; Kasper, P.; Kreymer, A.; Lebrun, P.; Shukla, S.; Vittone, M.; Bianco, S.; Fabbri, F. L.; Sarwar, S.; Zallo, A.; Culbertson, R.; Gardner, R. W.; Greene, R.; Wiss, J.; Alimonti, G.; Bellini, G.; Caccianiga, B.; Cinquini, L.; Di Corato, M.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Meroni, E.; Moroni, L.; Pedrini, D.; Perasso, L.; Sala, A.; Sala, S.; Torretta, D.; Buchholz, D.; Claes, D.; Gobbi, B.; O'Reilly, B.; Bishop, J. M.; Cason, N. M.; Kennedy, C. J.; Kim, G. N.; Lin, T. F.; Pušelji?, D. L.; Ruchti, R. C.; Shephard, W. D.; Swiatek, J. A.; Wu, Z. Y.; Arena, V.; Boca, G.; Castoldi, C.; Gianini, G.; Ratti, S. P.; Riccardi, C.; Vitulo, P.; Lopez, A.; Grim, G. P.; Paolone, V. S.; Yager, P. M.; Wilson, J. R.; Sheldon, P. D.; Davenport, F.; Filaseta, J. F.; Blackett, G. R.; Pisharody, M.; Handler, T.; Cheon, B. G.; Kang, J. S.; Kim, K. Y.; E687 Collaboration

1994-03-01

159

A precision measurement of the average lifetime of B hadrons  

Microsoft Academic Search

The average lifetime ofB hadrons was measured using data collected with the DELPHI detector at the LEP collider during 1991 and 1992. The measurement was performed using two different anayses. The first method was an improvement on a previous technique, which used charged particle impact parameter distributions. This analysis measured an average lifetime forB hadrons of(1)\\u000a$$\\\\tau _B = 1.542

P. Abreu; W. Adam; T. Adye; E. Agasi; Roy Aleksan; G. D. Alekseev; P P Allport; S. Almehed; F. M. L. Almeida Junior; S. J. Alvsvaag; Ugo Amaldi; A. Andreazza; P. Antilogus; W.-D. Apel; R. J. Apsimon; Y. Arnoud; B. Åsman; J.-E. Augustin; A. Augustinus; Paul Baillon; P. Bambade; F. Barao; R. Barate; Guido Barbiellini; Dimitri Yuri Bardin; G. J. Barker; A. Baroncelli; O. Barring; J. A. Barrio; Walter Bartl; M. J. Bates; Marco Battaglia; M. Baubillier; K.-H. Becks; M. Begalli; P. Beilliere; Yu A Belokopytov; P. Beltran; Alberto C Benvenuti; M. Berggren; D. Bertrand; F. Bianchi; M. Bigi; M. S. Bilenky; P. Billoir; J. Bjarne; D. Bloch; J. Blocki; S. Blyth; V. Bocci; P. N. Bogolubov; T. Bolognese; M. Bonesini; W. Bonivento; P. S. L. Booth; G. Borisov; C. Bosio; B. Bostjancic; S. Bosworth; O. Botner; B. Bouquet; C. Bourdarios; T. J. V. Bowcock; M. Bozzo; S. Braibant; P. Branchini; K. D. Brand; R. A. Brenner; H. Briand; C. Bricman; L. Brillault; R. C. A. Brown; J.-M. Brunet; L. Bugge; T. Buran; A. Buys; J. A. M. A. Buytaert; M. Caccia; M. Calvi; A. J. Camacho Rozas; R. Campion; T. Camporesi; V. Canale; K. Cabkocak; F. Cao; F. Carena; P. Carrilho; L. Carroll; R. Cases; Carlo Caso; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; L. Cerrito; V. Chabaud; A. Chan; Ph. Charpentier; J. Chauveau; P. Checchia; G. A. Chelkov; L. Chevalier; P V Chliapnikov; V. Chorowicz; J. T. M. Chrin; V. Cindro; P. Collins; J. L. Contreras; R. Contri; E. Cortina; G. Cosme; F. Couchot; H. B. Crawley; D J Crennell; G. Crosetti; J. Cuevas Maestro; S. Czellar; E. Dahl-Jensen; J. Dahm; B. Dalmagne; M. Dam; G. Damgaard; E. Daubie; A. Daum; P. D. Dauncey; M. Davenport; J. Davies; W. Da Silva; C. Defoix; P. Delpierre; N. Demaria; A. De Angelis; H. De Boeck; W. De Boer; S. De Brabandere; C. De Clercq; M. D. M. De Fez Laso; C. De La Vaissiere; D. De Lotto; A. De Min; L. De Paula; H. Dijkstra; L. Di Ciaccio; F. Djama; J. Dolbeau; M. Donszelmann; K. Doroba; M. Dracos; J. Drees; M. Dris; Y. Dufour; F. Dupont; D. Edsall; L.-O. Eek; R. Ehret; T. Ekelof; G. Ekspong; A. Elliot Peisert; M. Elsing; J.-P. Engel; N. Ershaidat; M. Espirito Santo; V. Falaleev; D. Fassouliotis; M. Feindt; A. Fenyuk; A Filippas-Tassos; T. A. Filipas; A. Firestone; H. Foeth; E. Fokitis; F. Fontanelli; K. A. J. Forbes; F. Formenti; J.-L. Fousset; S. Francon; B. Franek; P. Frenkiel; D. C. Fries; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; H. Fustenau; J. Fuster; D. Gamba; M. Gandelman; C. Garcia; J. Garcia; C. Gaspar; U. Gasparini; Ph. Gavillet; E. N. Gazis; J.-P. Gerber; P. Giacomelli; D. Gillespie; R. Gokieli; B. Golob; V. M. Golovatyuk; J. J. Gomez Y Cadenas; G. Gopal; L. Gorn; M. Gorski; V. Gracco; F. Grard; E. Graziani; G. Grosdidier; B. Grossetete; P. Gunnarsson; J. Guy; U. Haedinger; F. Hahn; M. Hahn; S Haider; Z. Hajduk; A. Hakansson; A. Hallgren; K. Hamacher; G. Hamel De Monchenault; W. Hao; F. J. Harris; V. Hedberg; R. Henriques; J. J. Hernandez; J. A. Hernando; P. Herquet; H. Herr; T. L. Hessing; C. O. Higgins; E. Higon; H. J. Hilke; T. S. Hill; S. D. Hodgson; S.-O. Holmogren; P. J. Holt; D J Holthuizen; P. F. Honore; M A Houlden; Josef Hrubec; K. Huet; K. Hultqvist; P. Ioannou; P.-S. Iversen; J. N. Jackson; R. Jacobsson; P. Jalocha; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; M. Jonker; L B Jönsson; P. Juillot; M. Kaiser; G Kalkanis; 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; A. Koch-Mehrin; J. H. Koehne; B. Koene; P. Kokkionias; M. Koratzinos; K. Korcyl; A. V. Korytov; V. Kostioukhine; C. Kourkoumelis; O. Kouznetsov; P. H. Kramer; M. Krammer; C. Kreuter; J. Krolikowski; I. Kronkvist; W. Krupinski; K. Kulka; K. Kurvinen; C. Lacasta; C. Lambropoulos; J. W. Lamsa; L. Lanceri; P. Langefeld; V. Lapin; I. Last; J.-P. Laugier; R. Lauhakangas; G. Leder; F. Ledroit; R. Leitner; Y. Lemoigne; J. Lemonne; G. Lenzen; V. Lepeltier; T. Lesiak; J. M. Levy; E. Lieb; D. Liko; R. Linder; A. Lipnicka; I. Lippi; B. Loerstad; M. Lokajicek; J. G. Loken; A. Lopez-Feernandez; M. A. Lopez Aguera; M A López-Aguera; D. Loukas; J. J. Lozano; P. Lutz; L. Lyons; G. Maehlum; J. Maillard; A. Maio; A. Maltezos; F. Mandl; J. Marco; B. Marechal; M. Margoni; J.-C. Marin; C. Mariotti; A. Markou; T. Maron; S. Marti; C. Martinez-Rivero; F. Martinez-Vidal; C. Mattekuzzi; G. Mathiae; M. Mazzucato; M. Mc. Cubbin; R. Mc Kay; R. Mc. Nulty; J. Medbo; C. Meroni; W. T. Meyer; M. Michelotto; E. Migliore; I. Mikulec; L. Mirabito; W. A. Mitaroff; G. V. Mitselmakher; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; W. J. Murray; B. Muryn; G. Myatt; F. Naraghi; F. L. Navarria; P. Negri; S. Nemecek; W. Neumann; N. Neumeister; R. Nicolaidou; B. S. Nielsen; V. Nikolaenko

1994-01-01

160

Measurement of the D/sup 0/ meson lifetime  

SciTech Connect

We report the measurement of the lifetime of the D/sup 0/ meson. The direct observation of the decay vertex distribution in the process D/sup 0/ ..-->.. K/sup -/..pi../sup +/ was made using a vertex chamber installed in the HRS detector at PEP. The measured lifetime is found to be tau/sub D/sup 0// = .42 +- .09 +- .06ps. 5 refs., 4 figs.

Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J.M.; Bylsma, B.G.; Chapman, J.; Cork, B.; DeBonte, R.

1986-01-01

161

Lifetime measurement of the 9s level of atomic francium.  

PubMed

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

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

2003-11-01

162

Lifetime improvements of multicrystalline silicon analysed by spatially resolved lifetime measurements  

Microsoft Academic Search

We investigated the gettering and passivation qualities of different industrial type processes for multicrystalline silicon solar cells. For gettering different phosphorus diffusion techniques forming the emitter including single and double side doping were realised. Additional hydrogen passivation by firing of a SiN:H-layer was performed. Processed wafers have been analysed by spatially resolved lifetime measurements. It is shown that the impact

G. Emanuel; W. Wolke; R. Preu

2003-01-01

163

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=0.34±0.09 eV, u2=0.39±0.12 eV, and u3=0.42±0.08 eV for the point defect state, and u1=1.12±0.08 eV and u2=1.37±0.13 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.

164

Tracking of the viability of Stenotrophomonas maltophilia bacteria population in polyvinylalcohol nanofiber webs by positron annihilation lifetime spectroscopy.  

PubMed

Polyvinylalcohol (PVA) fiber web containing embedded bacteria was prepared by electrospinning technique. From the point of the complex functionality of such potential delivery systems, it will be of impact how bacteria can survive in such artificial biotopes. The present study suggests a possible fast method for the tracking of the viability of the embedded bacteria based on the changes of the supramolecular structure of the polymeric delivery system caused by the metabolic product of the bacteria. Positron annihilation lifetime spectroscopy (PALS) was applied to track the free volume changes of the system in the course of storage. The PALS method sensitively detected the free volume changes, thus the viability of the bacteria in the polymeric fiber web. PMID:22449412

Vajdai, Attila; Szabó, Barnabás; Süvegh, Károly; Zelkó, Romána; Ujhelyi, Gabriella

2012-06-15

165

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

NASA Astrophysics Data System (ADS)

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

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

2008-03-01

166

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

167

A preliminary, precise measurement of the average B hadron lifetime  

SciTech Connect

The average B hadron lifetime was measured using data collected with the SLD detector at the SLC in 1993. From a sample of {approximately}50,000 Z{sup 0} events, a sample enriched in Z{sup 0} {yields} b{bar b} was selected by applying an impact parameter tag. The lifetime was extracted from the decay length distribution of inclusive vertices reconstructed in three dimensions. A binned maximum likelihood method yielded an average B hadron lifetime of {tau}{sub B} = 1.577 {plus_minus} 0.032(stat.) {plus_minus} 0.046(syst.) ps.

SLD Collaboration

1994-07-01

168

Measurement of the b hadron lifetime with the dipole method  

NASA Astrophysics Data System (ADS)

A measurement of the average lifetime of b hadrons has been performed with dipole method on a sample of 260 000 hadronic Z decays recorded with the ALEPH detector during 1991. The dipole is the distance between the vertices built in the opposite hemispheres. The mean dipole is extracted from all the events without attempting b enrichment. Comparing the average of the data dipole distribution with a Monte Carlo calibration curve obtained with different b lifetimes, an average b hadron lifetime of 1.51±0.08 ps is extracted.

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

1993-09-01

169

A preliminary measurement of the average B hadron lifetime  

SciTech Connect

The average B hadron lifetime was measured using data collected with the SLD detector at the SLC in 1993. From a sample of {approximately}50,000 Z{sup 0} events, a sample enriched in Z{sup 0} {yields} b{bar b} was selected by applying an impact parameter tag. The lifetime was extracted from the decay length distribution of inclusive vertices reconstructed in three dimensions. A binned maximum likelihood method yielded an average B hadron lifetime of {tau}{sub B} = 1.577{plus_minus}0.032(stat.){plus_minus}0.046(syst.) ps.

Manly, S.L. [Yale Univ., New Haven, CT (United States); SLD Collaboration

1994-09-01

170

Improved measurements of the B0 and B+ meson lifetimes  

NASA Astrophysics Data System (ADS)

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

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

1995-09-01

171

Precision Measurement of the ?b0 Baryon Lifetime  

NASA Astrophysics Data System (ADS)

The ratio of the ?b0 baryon lifetime to that of the B¯0 meson is measured using 1.0fb-1 of integrated luminosity in 7 TeV center-of-mass energy pp collisions at the LHC. The ?b0 baryon is observed for the first time in the decay mode ?b0?J/?pK-, while the B¯0 meson decay used is the well known B¯0?J/??+K- mode, where the ?+K- mass is consistent with that of the K¯*0(892) meson. The ratio of lifetimes is measured to be 0.976±0.012±0.006, in agreement with theoretical expectations based on the heavy quark expansion. Using previous determinations of the B¯0 meson lifetime, the ?b0 lifetime is found to be 1.482±0.018±0.012ps. In both cases, the first uncertainty is statistical and the second systematic.

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

2013-09-01

172

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

173

Uncertainty analysis in lifetime measurement for white light emitting diodes  

NASA Astrophysics Data System (ADS)

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

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

2012-10-01

174

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 µsec are determined. Presented at the 2013 AAPT Summer Meeting in Portland, Oregon. W36: Advanced Labs Workshop

Parks, James E.

2013-10-02

175

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

176

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

177

Lifetime measurement in the proton-unbound nucleus 109I  

NASA Astrophysics Data System (ADS)

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 109I. 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.; Cullen, D. M.; Ruotsalainen, P.; Scholey, C.; Angus, L.; Bäck, T.; Cederwall, B.; Dewald, A.; Fransen, C.; Grahn, T.; Greenlees, P. T.; Hackstein, M.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Lumley, N. M.; Mason, P. J. R.; Nieminen, P.; Nyman, M.; Pakarinen, J.; Pissulla, T.; Peura, P.; Rahkila, P.; Revill, J.; Rigby, S. V.; Rother, W.; Sandzelius, M.; Sarén, J.; Sorri, J.; Taylor, M. J.; Uusitalo, J.; Wady, P.; Qi, C.; Xu, F. R.

2011-11-01

178

The influence of microstructure on the sintering process in crystalline metal powders investigated by positron lifetime spectroscopy: I. Electrolytic and spherical copper powders  

NASA Astrophysics Data System (ADS)

We investigate the influence of microstructure (dislocations, and grain and subgrain boundaries) on the sintering process in compacts of electrolytic and spherical copper powders by means of positron lifetime spectroscopy. We compare the lifetime data obtained to the kinetics of the annealing out of vacancy clusters after low-temperature electron irradiation, and the kinetics of recovery and recrystallization after plastic deformation. The change of powder-particle and grain sizes with temperature is determined in a complementary study by metallography and x-ray line-profile analysis. At the intensive-shrinkage stage, the effective powder-particle size in electrolytic copper powder is 0953-8984/11/7/009/img7 and the grain size is 0953-8984/11/7/009/img8. Due to the dendritic morphology of the powder, the effective powder-particle size is much smaller than that determined by particle-size analysis 0953-8984/11/7/009/img9. Because of the small powder-particle and grain sizes, a measurable fraction of positrons annihilate at grain boundaries and in surface states, i.e. at inner pore surfaces. At higher temperatures 0953-8984/11/7/009/img10, grain boundaries are, besides a small surface component for compacts of electrolytic powder, the only detectable lattice defects in both powders. We find that the observed shrinkage rates can be explained - at least qualitatively - by Coble creep, while Nabarro-Herring and Kosevic (dislocation) creep seem to play only a minor role in the systems investigated.

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

1999-02-01

179

Positron annihilation studies of recrystallization in the subsurface zone induced by friction in magnesium—effect of the inhomogeneity on measured positron annihilation characteristics  

NASA Astrophysics Data System (ADS)

The discussion of the positron annihilation studies of crystal structure defects, like vacancies, dislocations, grain boundaries and the defect depth profile, is presented. The role of the positron implantation depth and positron diffusion in such studies has been considered in detail. For description of the measured annihilation characteristics the proposed theoretical models take into account both effects. The annealing studies of defects created in pure magnesium by compression or dry sliding-wear were used for demonstration of the discussed thesis. The positron lifetime measurements were applied for monitoring open volume defects behavior. It was demonstrated that annealing at the temperature of about 300 °C removes the defects created by compression. Application of the proposed model to description of the data obtained allows to determine the activation energy of the grain boundary mobility in pure magnesium equal to Q=0.56±0.18 eV. However, defects created by the dry sliding are not completely annealed up to the temperature of 500 °C. The defect depth profile induced by dry sliding evolves with the annealing temperature in such a way that at the worn surface concentration of defects gradually decreases but at the depth between 60 and 100 ?m the generation of new defects takes place at temperature of 150 and 225 °C. Above 300 °C the defects still are extended up to the depth of about 80 ?m.

Dryzek, Jerzy

2014-02-01

180

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

181

Ion induced modification in free volume in PN-6 and PES polymers by positron annihilation lifetime studies  

NASA Astrophysics Data System (ADS)

The irradiation of polymeric materials with swift heavy ions (SHI) results in a change of their free volume properties which have strong correlation with their macroscopic properties. Positron annihilation lifetime spectroscopy (PALS) has been developed into a powerful characterization tool for the study of free volume and free volume fraction in polymers. Polyamide nylon-6 (PN-6) and polyethersulphone (PES) films of thickness of 250 ?m were irradiated with C 5+ ions of energy 70 MeV from 15 UD Pelletron accelerator at Inter University Accelerator Centre (IUAC), New Delhi, India. PN-6 films were irradiated to the fluences of 10 11, 10 12 and 10 13 ions/cm 2 whereas PES films were irradiated to the fluences of 9.3 × 10 11, 9.3 × 10 12 and 1.2 × 10 13 ions/cm 2. Characterization of the effect of ion irradiation on free volume has been done by PALS. The average free volume and fractional free volume obtained from long lived component, attributed to ortho-positronium ( o-Ps) lifetime, are found to decrease with the fluence in both the cases. With increasing fluence, scissioned segments cross-link randomly, resulting in a decrease of average free volume due to overlapping of tracks.

Kumar, Rajesh; Prasad, Rajendra

2007-03-01

182

Measurement and Perturbation of Morphogen Lifetime: Effects on Gradient Shape  

PubMed Central

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

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

2011-01-01

183

Measurement and perturbation of morphogen lifetime: effects on gradient shape.  

PubMed

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

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

2011-10-19

184

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

185

Measurement of the average lifetime of B hadrons  

Microsoft Academic Search

The average lifetime ofB hadrons produced in hadronicZ0 decays has been measured with the DELPHI detector at LEP. The measurement is based on the analysis of the impact parameter distributions of highpt muons and hadrons. The resulting meanB lifetimes are tB=(1.30±0.10±0.08)ps and tB=(1.27±0.04±0.12)ps respectively, giving a combined value of tB=(1.28±0.10)ps. The hadronic sample was also used to measure the partialZ0

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

1992-01-01

186

Free volume anomalies in mixed-cation glasses revealed by positron annihilation lifetime spectroscopy (PALS).  

PubMed

PALS experiments reveal a minimum in ortho-positronium (o-Ps) lifetimes and a maximum in the corresponding intensities that emerge when mixed-cation (Li/Na) borate glasses are heated from ambient temperatures up to 473 K. These free volume 'anomalies' appear to be a true manifestation of the mixed alkali effect (MAE). They are consistent with a mechanism of ion transport involving cooperation between hops of unlike cations, resulting in increased disturbance of the glass network. The result lends support to the dynamic structure model. PMID:19787916

Ingram, Malcolm D; Pas, Steven J; Cramer, Cornelia; Gao, Yong; Hill, Anita J

2005-04-21

187

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

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

188

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

189

Lifetimes Measurement for High Spin States in 107Ag  

NASA Astrophysics Data System (ADS)

The excited states in 107Ag were populated through the heavy-ion fusion-evaporation reaction 100Mo (11B, 4n) 107Ag at a beam energy of 46 MeV. 12 Compton suppressed HPGe detectors and 2 planar HPGe detectors were employed to detect the de-excited ? rays from the reaction residues. Lifetimes of high spin states in 107Ag have been measured using the Doppler shift attenuation method (DSAM) and the deduced B(M1) and B(E2) transition probabilities have been derived from the measured lifetimes.

Yao, S. H.; Wu, X. G.; He, C. Y.; Zhang, B.; Zheng, Y.; Li, G. S.; Li, C. B.; Hu, S. P.; Cao, X. P.; Yu, B. B.; Zhu, L. H.; Xu, C.; Cheng, Y. Y.

2013-11-01

190

A capacitance servo control plunger for accurate lifetime measurement  

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

191

Measurement of the average lifetime of b hadrons  

NASA Astrophysics Data System (ADS)

The average lifetime of b hadrons has been measured using the L3 detector at LEP, running at ? 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 hadron lifetime was measured to be ?b = (1535 ± 35 ± 28) fs, where the first error is statistical and the second includes both the experimental and the theoretical systematic uncertainties.

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

1993-11-01

192

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

SciTech Connect

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

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

2011-12-01

193

Temperature dependence of the free volume from positron lifetime experiments and its relation to structural dynamics: phenylphthalein-dimethylether.  

PubMed

Positron annihilation lifetime spectroscopy (PALS) was used to study the microstructure of the free volume in the temperature range between 103 K and 393 K in phenylphthalein-dimethylether (PDE), a low-molecular-weight glass former. Using the routine LIFETIME9.0, the ortho-positronium (o-Ps) lifetime distribution was analyzed, and from this, the volume distribution gn(vh) of subnanometer-size holes was calculated. From a comparison of PALS and specific volume data, the number density and the volume fraction of holes were estimated. These free-volume data, as a function of temperature, were used to test the validity of the Cohen-Turnbull (CT) free-volume theory. It was found that the structural relaxation from dielectric spectroscopy can be described by the CT theory after introducing a corrected free volume (Vf-DeltaV), where DeltaV=0.014 cm3/g. The extended free-volume theory of Cohen and Grest can be fitted to the dielectric-relaxation and free-volume data, but the parameters of both fits are not consistent. PDE shows some peculiar features. The "knee" in the o -Ps lifetime expansion and crossover in temperature dependence of the frequency of the primary dielectric relaxation process occur at different temperatures. In addition, the change in the Vogel-Fulcher-Tammann parameters at TB/Tg=1.1 has no observable effect on the mean free volume vh (or Vf). The size of the smallest representative freely fluctuating subsystem, VSV estimated from the standard deviation sigmah of gn(vh), decreases from 4.1 nm3 to 2.6 nm3 when the temperature increases from T/Tg=1.0 to 1.15. Correspondingly, the length of dynamic heterogeneity, xi=VVS1/3, decreases from 1.6 nm to 1.4 nm. It is concluded that at T/Tg approximately 1.10=TB/Tg the system transforms from a heterogeneous to a homogeneous (true) liquid. PMID:19113134

Dlubek, Günter; Shaikh, Muhammad Qasim; Rätzke, Klaus; Faupel, Franz; Paluch, Marian

2008-11-01

194

Temperature dependence of the free volume from positron lifetime experiments and its relation to structural dynamics: Phenylphthalein-dimethylether  

NASA Astrophysics Data System (ADS)

Positron annihilation lifetime spectroscopy (PALS) was used to study the microstructure of the free volume in the temperature range between 103K and 393K in phenylphthalein-dimethylether (PDE), a low-molecular-weight glass former. Using the routine LIFETIME9.0, the ortho-positronium ( o -Ps) lifetime distribution was analyzed, and from this, the volume distribution gn(vh) of subnanometer-size holes was calculated. From a comparison of PALS and specific volume data, the number density and the volume fraction of holes were estimated. These free-volume data, as a function of temperature, were used to test the validity of the Cohen-Turnbull (CT) free-volume theory. It was found that the structural relaxation from dielectric spectroscopy can be described by the CT theory after introducing a corrected free volume (Vf-?V) , where ?V=0.014cm3/g . The extended free-volume theory of Cohen and Grest can be fitted to the dielectric-relaxation and free-volume data, but the parameters of both fits are not consistent. PDE shows some peculiar features. The “knee” in the o -Ps lifetime expansion and crossover in temperature dependence of the frequency of the primary dielectric relaxation process occur at different temperatures. In addition, the change in the Vogel-Fulcher-Tammann parameters at TB/Tg=1.1 has no observable effect on the mean free volume ?vh? (or Vf ). The size of the smallest representative freely fluctuating subsystem, ?VSV? estimated from the standard deviation ?h of gn(vh) , decreases from 4.1nm3to2.6nm3 when the temperature increases from T/Tg=1.0 to 1.15. Correspondingly, the length of dynamic heterogeneity, ?=?VVS?1/3 , decreases from 1.6nmto1.4nm . It is concluded that at T/Tg?1.10=TB/Tg the system transforms from a heterogeneous to a homogeneous (true) liquid.

Dlubek, Günter; Shaikh, Muhammad Qasim; Rätzke, Klaus; Faupel, Franz; Paluch, Marian

2008-11-01

195

Fluorescence lifetime as a new parameter in analytical cytology measurements  

NASA Astrophysics Data System (ADS)

A phase-sensitive flow cytometer has been developed to quantify fluorescence decay lifetimes on fluorochrome-labeled cells/particles. This instrument combines flow cytometry (FCM) and frequency-domain fluorescence spectroscopy measurement principles to provide unique capabilities for making phase-resolved lifetime measurements, while preserving conventional FCM capabilities. Cells are analyzed as they intersect a high-frequency, intensity-modulated (sine wave) laser excitation beam. Fluorescence signals are processed by conventional and phase-sensitive signal detection electronics and displayed as frequency distribution histograms. In this study we describe results of fluorescence intensity and lifetime measurements on fluorescently labeled particles, cells, and chromosomes. Examples of measurements on intrinsic cellular autofluorescence, cells labeled with immunofluorescence markers for cell- surface antigens, mitochondria stains, and on cellular DNA and protein binding fluorochromes will be presented to illustrate unique differences in measured lifetimes and changes caused by fluorescence quenching. This innovative technology will be used to probe fluorochrome/molecular interactions in the microenvironment of cells/chromosomes as a new parameter and thus expand the researchers' understanding of biochemical processes and structural features at the cellular and molecular level.

Steinkamp, John A.; Deka, Chiranjit; Lehnert, Bruce E.; Crissman, Harry A.

1996-05-01

196

INSTRUMENTS AND METHODS OF INVESTIGATION: Positron annihilation spectroscopy in materials structure studies  

Microsoft Academic Search

A relatively new method of materials structure analysis --- positron annihilation spectroscopy (PAS) --- is reviewed. Measurements of positron lifetimes, the determination of positron 3gamma- and 2gamma-annihilation probabilities, and an investigation of the effects of different external factors on the fundamental characteristics of annihilation constitute the basis for this promising method. The ways in which the positron annihilation process operates

Viktor I. Grafutin; Evgenii P. Prokop'ev

2002-01-01

197

Lifetime measurement of the 8s level in francium  

SciTech Connect

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

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

2005-06-15

198

Measurement of the B+ and B0 meson lifetimes  

Microsoft Academic Search

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

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

1994-01-01

199

Lifetime measurements of the 7d levels of atomic francium  

Microsoft Academic Search

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

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

2000-01-01

200

Lifetime measurement of excited states in /sup 105/Ag  

SciTech Connect

The levels up to about 2.1 MeV in /sup 105/Ag were excited via /sup 105/Pd(p,n..gamma..) reaction. For the first time, lifetimes of energy levels at 1023, 1042, 1097, 1166, 1243, 1295, 1328, 1386, 1442, 1543, 1558, 1587, 1719, 1923, and 2081 keV have been measured using the Doppler shift attenuation technique.

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

1986-11-01

201

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. Barillère; 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. Maña; 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

202

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 1.455±0.046(stat.)±0.006(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.; Bjørnstad, 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.; Lefèvre, 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

203

HEAO 3 measurements of the atmospheric positron annihilation line  

NASA Technical Reports Server (NTRS)

The atmospheric positron annihilation line at 511 keV was the first gamma-ray line observed which originates from processes of astrophysical importance. Measurements of the properties of a positron annihilation line make it possible to determine many of the physical conditions present at the source of emission. An investigation was conducted of the 511-keV line measured with the HEAO C-1 experiment. The HEAO C-1 experiment consisted of a cluster of four, large, high-purity germanium detectors surrounded by an active anticoincidence CsI shield. A strong atmospheric line was measured at 511.07 + or - 0.10 keV. The net atmospheric emission has been accurately determined as a function of geomagnetic latitude and varies from 0.01 photons/sq cm-sec-sr near the magnetic equator to 0.035 photons/sq cm-sec-sr at a latitude of 55 deg.

Mahoney, W. A.; Ling, J. C.; Jacobson, A. S.

1981-01-01

204

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

205

Inhomogeneous dephasing masks coherence lifetimes in ensemble measurements.  

PubMed

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. PMID:22559497

Pelzer, Kenley M; Griffin, Graham B; Gray, Stephen K; Engel, Gregory S

2012-04-28

206

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

207

Inhomogeneous dephasing masks coherence lifetimes in ensemble measurements  

NASA Astrophysics Data System (ADS)

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.; Gray, Stephen K.; Engel, Gregory S.

2012-04-01

208

A precise measurement of the $\\\\tau$ lepton lifetime  

Microsoft Academic Search

The tau lepton lifetime has been measured using three different methods with the DELPHI detector. Two measurements of one-prong decays are combined, accounting for correlations, giving a result of \\\\tau_\\\\tau = 291.8 \\\\pm 3.3 \\\\mbox{ (stat.)} \\\\pm 2.0 \\\\mbox{(sys.) fs} while the decay length distribution of three-prong decays gives the result \\\\tau_{\\\\tau} = 286.7 \\\\pm 4.9 \\\\mbox{ (stat.)} \\\\pm 3.3

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 Åsman; J E Augustin; A Augustinus; Paul Baillon; P Bambade; F Barão; R Barate; 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 Beillière; 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; T Brenke; R A Brenner; C Bricman; L Brillault; R C A Brown; P Brückman; J M Brunet; L Bugge; T Buran; T Burgsmüller; P Buschmann; 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; 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; P D Dauncey; Martyn Davenport; W Da Silva; C Defoix; A Deghorain; 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 Vaissière; 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; M C Espirito-Santo; E Falk; D Fassouliotis; Michael Feindt; 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; 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; L N Gerdyukov; M Gibbs; R Gokieli; B Golob; Gian P Gopal; L Gorn; M Górski; Yu Guz; Valerio Gracco; E Graziani; G Grosdidier; K Grzelak; S A Gumenyuk; P Gunnarsson; M Günther; J Guy; F Hahn; S Hahn; 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; S Hoorelbeke; M A Houlden; Josef Hrubec; K Huet; K Hultqvist; 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; F Kapusta; K Karafasoulis; M Karlsson; E Karvelas; S Katsanevas; E C Katsoufis; R Keränen; Yu A Khokhlov; B A Khomenko; N N Khovanskii; B J King; N J Kjaer; H Klein; A Klovning; P M Kluit; B Köne; P Kokkinias; M Koratzinos; K Korcyl; 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; C Maocun; 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; R McKay; R McNulty; J Medbo; C Meroni; S Meyer; W T Meyer; A Myagkov; M Michelotto; E Migliore; L Mirabito; Winfried A Mitaroff; U Mjörnmark; T Moa; R Møller; 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 Pagès; H Palka; T D Papadopoulou; K Papageorgiou; L Pape; C Parkes; F Parodi; A Passeri; M Pegoraro; L Peralta; H Pernegger; Manfred Pernicka; A Perrotta; C Petridou; A Petrolini; M Petrovykh; H T Phillips; G Piana; F Pierre; M Pimenta; M Pindo; S Plaszczynski; O Podobrin; M E Pol; G Polok; P Poropat; V Pozdnyakov; M Prest; P Privitera; N Pukhaeva; D Radojicic

1995-01-01

209

Phase dependence of positron annihilation in tristearin.  

NASA Technical Reports Server (NTRS)

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

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

1972-01-01

210

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

211

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

NASA Astrophysics Data System (ADS)

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

Schewe, James Edward

212

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

213

Cosmic Electron and Positron Spectra Measured in 2002  

NASA Astrophysics Data System (ADS)

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

Evenson, P.; Clem, J.

2002-12-01

214

Lifetime Measurements of Tagged Exotic- and Unbound Nuclear States  

SciTech Connect

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

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

2011-11-30

215

Measurement of the lifetime difference between Bs mass eigenstates.  

PubMed

We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.05(+0.16)(-0.13) +/- 0.02) ps and tau(H) = (2.07(+0.58)(-0.46) +/- 0.03) ps. Expressed in terms of the difference DeltaGamma(s) and average Gamma(s), of the decay rates of the two eigenstates, the results are DeltaGamma(s)/Gamma(s) = (65(+25)(-33) +/- 1)% and DeltaGamma(s) = (0.47(+0.19)(-0.24) +/- 0.01) ps(-1). PMID:15783473

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

2005-03-18

216

Improved measurement of the B 0 and B + meson lifetimes  

NASA Astrophysics Data System (ADS)

The lifetimes of the B 0 and B + mesons have been measured with the Aleph detector at LEP, using approximately 3 million hadronic Z decays collected in the period 1991 1994. In the first of three methods, semileptonic decays of B 0 and B + mesons were partially reconstructed by identifying events containing a lepton with an associated D*- orbar D^0 meson. The second method used fully reconstructed B 0 and B + mesons. The third method, used to measure the B 0 lifetime, employed a partial reconstruction technique to identify B 0? D*- ? + X decays. The combined results are begin{gathered} tau _0 = 1.55 ± 0.06 ± 0.03 ps, \\ tau _ + = 1.58 ± 0.09 ± 0.03 ps, \\ tfrac{{tau _ + }}{{tau _0 }} = 1.03 ± 0.08 ± 0.02. \\ .

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

1996-03-01

217

Lifetime measurements of the 7D levels of atomic francium  

Microsoft Academic Search

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

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

2000-01-01

218

Lifetime measurements of the 7p levels of atomic francium  

Microsoft Academic Search

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

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

1998-01-01

219

Updated precision measurement of the average lifetime of B hadrons  

NASA Astrophysics Data System (ADS)

The measurement of the average lifetime of B hadrons using inclusively reconstructed secondary vertices has been updated using both an improved processing of previous data and additional statistics from new data. This has reduced the statistical and systematic uncertainties and gives ?B = 1.582 ± 0.011 (stat.) ± 0.027 (syst.) ps. Combining this result with the previous result based on charged particle impact parameter distributions yields ?B = 1.575 ± 0.010 (stat.) ± 0.026 (syst.) ps.

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

1996-02-01

220

Measurements of the B s 0 and ? b 0 lifetimes  

Microsoft Academic Search

This paper presents updated measurements of the lifetimes of the Bs0 meson and the ?b0 baryon using 4.4 million hadronic Z0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of Bs0 decays is obtained using Ds??+ combinations, where the Ds? is fully reconstructed in the ???, K?0K? and K?K0S decay channels and partially reconstructed

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

1998-01-01

221

Measurements of the Bs0 and Lambdab0 lifetimes  

Microsoft Academic Search

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

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

1998-01-01

222

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

223

An improved measurement of the B S 0 lifetime  

Microsoft Academic Search

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

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

1995-01-01

224

Lifetime measurements probing triple shape coexistence in 175Au  

NASA Astrophysics Data System (ADS)

Lifetimes of the low-lying excited states in the very neutron-deficient nucleus 175Au have been measured by the recoil-distance Doppler-shift method using ?-ray spectra obtained with the recoil-decay tagging technique. Transition quadrupole moments and reduced transition probabilities extracted for this odd-Z nucleus indicate the existence of three different shapes and the competition between collective and noncollective structures.

Watkins, H.; Joss, D. T.; Grahn, T.; Page, R. D.; Carroll, R. J.; Dewald, A.; Greenlees, P. T.; Hackstein, M.; Herzberg, R.-D.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Kröll, T.; Krücken, R.; Labiche, M.; Leino, M.; Lumley, N.; Maierbeck, P.; Nyman, M.; Nieminen, P.; O'Donnell, D.; Ollier, J.; Pakarinen, J.; Peura, P.; Pissulla, T.; Rahkila, P.; Revill, J. P.; Rother, W.; Ruotsalainen, P.; Rigby, S. V.; Sarén, J.; Sapple, P. J.; Scheck, M.; Scholey, C.; Simpson, J.; Sorri, J.; Uusitalo, J.; Venhart, M.

2011-11-01

225

Positron annihilation study of microvoids in centrifugally atomized 304 stainless steel  

Microsoft Academic Search

Positron trapping in microvoids was studied by positron-lifetime and positron Doppler line-shape measurements of centrifugally atomized 304 stainless-steel powder, which was hot-isostatically-press consolidated. This material contained a concentration of several times 1023\\/m3 of 1.5-nm-diam microvoids. Positron annihilation was strongly influenced by the microvoids in that a very long lifetime component ?3 of about 600 ps resulted. The intensity of the

J. Y. Kim; J. G. Byrne

1993-01-01

226

Fluorescence lifetime measurements of boronate derivatives to determine glucose concentration  

SciTech Connect

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

Gable, J H

2000-06-01

227

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

228

A Precise measurement of the B0(s) lifetime  

SciTech Connect

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

Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; /Buenos Aires U. /Rio de Janeiro, CBPF /Rio de Janeiro State U. /Sao Paulo, IFT /Alberta U. /Simon Fraser U. /York U., Canada /McGill U. /Beijing, Inst. High Energy Phys. /Hefei, CUST /Andes U., Bogota

2006-04-01

229

Microscopic basis of free-volume concept as studied by quasielastic neutron scattering and positron annihilation lifetime spectroscopy  

NASA Astrophysics Data System (ADS)

We have reexamined the free-volume concept presented by Cohen and Turnbull on the basis of two microscopic quantities: the excess mean-square displacement f and the total free volume VPA,t, of poly- butadiene evaluated from the quasielastic neutron scattering and the positron annihilation lifetime spectroscopy (PALS) data, respectively. Comparing with the viscosity ? we found two relations, ?=?0 exp u 20/f and ?=?0 exp V*PA,0/VPA,t=?0 exp V*PA,0/vPA,f, where u20, V*PA,0 and v*PA,0 are the critical values for the mean-square displacement, the total PALS free volume, and the PALS free volume per molecule, respectively, and further v*PA,0=V*PA,0/N, N being the total number of molecules or segments. On the basis of these relations, we discuss the microscopic basis of the free-volume theory. The experimentally evaluated critical values u20 and v*PA,0 are much larger than the average values of f and vPA,f calculated from the distributions. This has been explained from the low probability of escaping motions from a molecular cage. The free volume per monomer and the free-volume fraction were calculated from the excess mean-square displacement f. The former was compared with the free-volume hole obtained by PALS, suggesting that 22 monomers are required for one PALS free-volume hole. The free-volume fraction obtained from the excess mean-square displacement was found to be 6.4% at 250 K, which is in reasonable agreement with that evaluated from the rheological data (9.0%).

Kanaya, T.; Tsukushi, T.; Kaji, K.; Bartos, J.; Kristiak, J.

1999-08-01

230

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 (H2) to reversed micellar (L2) 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

231

Lifetime Measurements and Coulomb Excitation of Light Hg Nuclei  

NASA Astrophysics Data System (ADS)

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

Petts, A.; Butler, P. A.; Grahn, T.; Blazhev, A.; Bree, N.; Bruyneel, B.; Cederkäll, J.; Clement, E.; Cocolios, T. E.; Dewald, A.; Eberth, J.; Fraile, L.; Fransen, C.; Hornillos, M. B. Gómez; Greenlees, P. T.; Görgen, A.; Guttormsen, M.; Hadynska, K.; Helariutta, K.; Herzberg, R.-D.; Huyse, M.; Jenkins, D. G.; Jolie, J.; Jones, P.; Julin, R.; Juutinen, S.; Ketelhut, S.; Knapen, S.; Kröll, T.; Krücken, R.; Larsen, A. C.; Leino, M.; Ljungvall, J.; Maierbeck, P.; Marley, P. L.; Melon, B.; Napiorkowski, P. J.; Nyman, M.; Page, R. D.; Pakarinen, J.; Pascovici, G.; Patronis, N.; Peura, P. J.; Piselli, E.; Pissulla, Th.; Rahkila, P.; Reiter, P.; Sarén, J.; Scheck, M.; Scholey, C.; Semchenkov, A.; Siem, S.; Stefanescu, I.; Sorri, J.; Uusitalo, J.; van de Walle, J.; van Duppen, P.; Voulot, D.; Wadsworth, R.; Warr, N.; Weisshaar, D.; Wenander, F.; Zielinska, M.

2009-01-01

232

Phosphors’ lifetime measurement employing the Time Between Photons method  

NASA Astrophysics Data System (ADS)

The Time Between Photons theory (hereafter TBP) is applied to the evaluation of the lifetime of phosphors employed in the Ion Photon Emission Microscope (IPEM). IPEM allows Radiation Effects Microscopy (REM) without focused ion beams and appears to be the best tool for the radiation hardness assessment of modern integrated circuit at cyclotron energies. IPEM determines the impact point of a single ion onto the sample by measuring the light spot produced on a thin phosphor layer placed on the sample surface. The spot is imaged by an optical microscope and projected at high magnification onto a Position Sensitive Detector (PSD). Phosphors, when excited by an ion, emit photons with a particular lifetime, which is important to evaluate. We measured the statistical distribution of the Time Between consecutive detected Photons (TBP) for several phosphors and have been able to link it to their lifetime employing a theory that is derived in this paper. The single-photon signals are provided by the IPEM-PSD, or faster photomultipliers when high-speed materials had to be assessed.

Rossi, P.; Doyle, B. L.; Brice, D. K.; Vizkelethy, G.; McDaniel, F. D.; Branson, J. V.

2009-06-01

233

Measurement of the Lifetime Difference in the Bs0 System  

Microsoft Academic Search

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

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

2005-01-01

234

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

235

Lifetime measurement for the 21+ state of Hf170  

NASA Astrophysics Data System (ADS)

The lifetime of the J?=21+ state of Hf170 at 100.8 keV was measured. Excited states of Hf170 were populated with the Gd158(O16,4n?) reaction at the TANDEM-LINAC facility of the State University of New York (SUNY) at Stony Brook. A lifetime of ?=1.74±0.06 ns was found using the delayed ?-radiofrequency coincidence method with respect to the pulsed LINAC beam. It corresponds to an E2 transition strength of 181±6 W.u. to the J?=01+ ground state. With its increased precision, by one order of magnitude with respect to previous literature, this value serves as a normalization parameter for collective models for this nucleus.

Costin, A.; Ahn, T.; Bochev, B.; Dusling, K.; Li, T. C.; Pietralla, N.; Rainovski, G.; Rother, W.

2006-12-01

236

An improved measurement of the B0S lifetime  

NASA Astrophysics Data System (ADS)

This letter presents an updated measurement of the lifetime of the B s0 meson using 3.6 million hadronic Z 0 decays recorded by the OPAL detector at LEP from 1990 to 1994. A sample of B s0 decays is obtained using D s-? + combinations, where the D s- is reconstructed in either the ??- or K ?0K - decay mode. From 79 ± 13 D x? combinations attributed to B s0 decays in this data sample, we measure ?(B s0) = 1.54 -0.21+0.25 ± 0.06 ps, where the errors are statistical and systematic, respectively.

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

1995-02-01

237

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

238

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

239

Measurement of the neutral B meson lifetime using partial reconstruction  

NASA Astrophysics Data System (ADS)

We present here the first measurement of the B 0 lifetime using partial reconstruction in B 0 ? D*-rho+ decay. A sample of approximately 5500 B0 ? D*-rho+ events were identified among 22.7 million BB¯ pairs collected by the BABAR experiment during the years 1999--2000. With this data, the B0 lifetime is measured to be 1.616 +/- 0.064 +/- 0.075 ps, in good agreement with the world average. This measurement demonstrates that is it possible to use this technique to perform time-dependent B0 decay analysis that is central to the measurement of the charge-parity ( CP ) asymmetries. Investigation of CP observables through measurements of the decays of B 0 mesons is the primary goal of the BABAR experiment at the PEP-II storage ring located at Stanford Linear Accelerator Center (SLAC). As the B0 particle decays to final states that are directly sensitive to the CP parameter gamma are highly suppressed, a promising alternative approach is to use the final state B0 ? D *h. Using the partial event reconstruction analysis method it is possible to compensate for the small CP asymmetries in this decay.

Krishnamurthy, Mahalaxmi

240

Construction of a positron microbeam in JAEA  

NASA Astrophysics Data System (ADS)

We have developed a positron microbeam using magnetic lenses based on the commercial scanning electron microscope (SEM). A slow positron beam was generated using a handmade source with 22Na and a solid neon moderator. The beam diameter was 3.9 ?m on a target. Two-dimensional image of S parameter was successfully obtained. By introducing a beam pulsing section, positron lifetime measurement beam is also available.

Maekawa, Masaki; Kawasuso, Atsuo

2008-10-01

241

Evolution of Nuclear Shapes at High Spins as Determined by Lifetime Measurements.  

National Technical Information Service (NTIS)

Lifetime measurements of high spin states are obtained by the Doppler-shift recoil-distance method. Transition quadrupole moments are extracted from these data. Expanding on earlier experimental work, lifetime and moment of inertia measurements were made ...

N. Johnson

1986-01-01

242

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

243

Accurate Lifetime Measurements of Superdeformed Bands in A ~ 80 Nuclei  

NASA Astrophysics Data System (ADS)

Comparative measurements of the lifetimes of yrast superdeformed (SD) states in 80-83Sr, 83Y, and 84Zr have been performed using the Doppler-shift attenuation method. Thus, the transition quadrupole moments ( Qt) of these structures have been determined accurately. The yrast SD bands in 80-83Sr possess Qt~3.5 e b, while the 83Y and 84Zr cases display Qt = 4.4 e b and 5.6 e b, respectively. Intruder orbital assignments based on these results demonstrate a previously unnoticed transition in the structure of the SD bands when the proton number changes from Z = 38 to Z>=39.

Lerma, F.; Devlin, M.; Lafosse, D. R.; Sarantites, D. G.; Wyss, R.; Baktash, C.; Clark, R. M.; Lee, I. Y.; Macchiavelli, A. O.; MacLeod, R. W.; Soltysik, D.; Tabor, S. L.

1999-12-01

244

Lifetime measurement of the yrast 8^+ state in ^70As  

NASA Astrophysics Data System (ADS)

In the A ˜ 70 region of the nuclear chart, the structure of excited nuclear states is sensitive to the occupation of the g9/2 orbital. In particular, the excited states of the odd-odd nucleus ^70As have been discussed in terms of the coupling of the valence proton and neutron to form two-particle configurations of ?g9/2?g9/2 orbitals. To examine this, the lifetime of the 8^+ yrast state in ^70As was measured using the gamma-ray line shape technique at the NSCL. Gamma-rays emitted at the reaction target position were measured with the SeGA HPGe array in coincidence with reaction residues detected in the S800 spectrometer. The transition strength of the lowest 8^+ level, which is among the excited states suggested to be part of these two-particle configurations, was obtained from the measured lifetimes. The validity of this assignment to a ?g9/2?g9/2 configuration and the possible evolution of such high-spin orbitals in neutron-deficient As nuclei will be discussed in light of the present results.

Morse, Chris; Iwasaki, Hironori; Lemasson, Antoine; Baugher, Travis; Bazin, Daniel; Berryman, Jill; Gade, Alexandra; McDaniel, Sean; Ratkiewicz, Andrew; Stroberg, Steven; Voss, Phil; Weisshaar, Dirk; Wimmer, Kathrin; Winkler, Ryan; Dewald, Alfred; Fransen, Christoph; Nichols, Adam; Wadsworth, Robert

2012-10-01

245

A precise measurement of the tau lepton lifetime  

NASA Astrophysics Data System (ADS)

The tau lepton lifetime has been measured using three different methods with the DELPHI detector. Two measurements of one-prong decays are combined, accounting for correlations, giving a result of ?? = 291.8 ± 3.3 (stat.) ± 2.0(sys.) fs while the decay length distribution of three-prong decays gives the result ?? = 286.7 ± 4.9 (stat.) ±3.3 (sys.) fs. Combining the results presented here with previous DELPHI measurements, we get ?? = 291.4 ± 3.0 fs and find that the ratio of the coupling constant for tau decay relative to that for muon decay is 0.990 ± 0.009, compatible with lepton universality.

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

1996-02-01

246

B(S) LIFETIME DIFFERENCE MEASUREMENTS FROM THE TEVATRON.  

SciTech Connect

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

YIP, K.

2006-07-02

247

Lifetime measurements by open circuit voltage decay in GaAs and InP diodes  

NASA Technical Reports Server (NTRS)

Minority carrier lifetimes in the base of solar cells made on GaAs and InP were measured by the open-circuit voltage decay method. The measurement technique and the conditions under which the minority carrier lifetimes can be measured are described. Minority carrier lifetimes ranging from 1.6 to 34 ns in InP of different doping concentrations were measured. A minority carrier lifetime of 6 ns was measured in n-type GaAs, which agrees well with the lifetime of 5.7 ns measured by transient microwave reflection.

Bhimnathwala, H. G.; Tyagi, S. D.; Bothra, S.; Ghandhi, S. K.; Borrego, J. M.

1990-01-01

248

Mass and lifetime measurements of exotic nuclei in storage rings.  

PubMed

Mass and lifetime measurements lead to the discovery and understanding of basic properties of matter. The isotopic nature of the chemical elements, nuclear binding, and the location and strength of nuclear shells are the most outstanding examples leading to the development of the first nuclear models. More recent are the discoveries of new structures of nuclides far from the valley of stability. A new generation of direct mass measurements which allows the exploration of extended areas of the nuclear mass surface with high accuracy has been opened up with the combination of the Experimental Storage Ring ESR and the FRragment Separator FRS at GSI Darmstadt. In-flight separated nuclei are stored in the ring. Their masses are directly determined from the revolution frequency. Dependent on the half-life two complementary methods are applied. Schottky Mass Spectrometry SMS relies on the measurement of the revolution frequency of electron cooled stored ions. The cooling time determines the lower half-life limit to the order of seconds. For Isochronous Mass Spectrometry IMS the ring is operated in an isochronous ion-optical mode. The revolution frequency of the individual ions coasting in the ring is measured using a time-of-flight method. Nuclides with lifetimes down to microseconds become accessible. With SMS masses of several hundreds nuclides have been measured simultaneously with an accuracy in the 2 x 10(-7)-range. This high accuracy and the ability to study large areas of the mass surface are ideal tools to discover new nuclear structure properties and to guide improvements for theoretical mass models. In addition, nuclear half-lives of stored bare and highly charged ions have been measured. This new experimental development is a significant progress since nuclear decay characteristics are mostly known for neutral atoms. For bare and highly charged ions new nuclear decay modes become possible, such as bound-state beta decay. Dramatic changes in the nuclear lifetime have been observed in highly charged ions compared to neutral atoms due to blocking of nuclear decay channels caused by the modified atomic interaction. High ionization degrees prevail in hot stellar matter and thus these experiments have great relevance for the understanding of the synthesis of elements in the universe and astrophysical scenarios in general. PMID:18636527

Franzke, Bernhard; Geissel, Hans; Münzenberg, Gottfried

2008-01-01

249

Measurement of the B0 and B- meson lifetimes  

NASA Astrophysics Data System (ADS)

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

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

2000-01-01

250

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

251

Ligament coarsening in nanoporous gold: Insights from positron annihilation study  

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

252

Lifetime measurements and magnetic rotation in 107Ag  

NASA Astrophysics Data System (ADS)

The excited states in 107Ag were populated through the heavy-ion fusion evaporation reaction 100Mo (11B, 4n) 107Ag at a beam energy of 46 MeV. Lifetimes of high-spin states in 107Ag have been measured through the Doppler shift attenuation method. The deduced B (M1) values, gradually decreasing with increasing spin, clearly demonstrate that both the yrast positive-parity band and the yrast negative-parity band in 107Ag are magnetic rotation bands. Furthermore, experimental deduced B (M1) values for the yrast positive-parity band are compared with the predictions of the particle rotor model. The approximate agreement between theoretical calculations and experimental results further confirms the mechanism of magnetic rotation for the yrast positive-parity band. In addition, a systematic investigation shows the evolution of the magnetic rotation mechanism in the A ?110 mass region.

Yao, S. H.; Ma, H. L.; Zhu, L. H.; Wu, X. G.; He, C. Y.; Zheng, Y.; Zhang, B.; Li, G. S.; Li, C. B.; Hu, S. P.; Cao, X. P.; Yu, B. B.; Xu, C.; Cheng, Y. Y.

2014-01-01

253

Lifetime Measurements in 134Pr and Chirality in Nuclei  

NASA Astrophysics Data System (ADS)

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

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

254

Positron Annihilation Study of Y1Ba2Cu306+delta Superconducting Ceramics.  

National Technical Information Service (NTIS)

The positron annihilation lifetime spectra of Y1Ba2Cu3O(6 + delta) (0 < delta < 1.0) samples with different oxygen contents were measured. The relationship between positron lifetime and the oxygen vacancy in the ceramics was discussed, based on the positr...

A. Chen Y. Zhi B. R. Li X. L. Zhang X. H. Li S. J. Wang

1992-01-01

255

Positron lifetime studies of the dose dependence of nanohole free volumes in ion-irradiated conducting poly-(ethylene-oxide) salt polymers  

NASA Astrophysics Data System (ADS)

Polymer based ion conducting materials have potential applications as an electrolyte and separator in the field of lithium batteries. Solid polymer electrolytes for lithium batteries are one of the best applications. The irradiation of polymeric materials with swift heavy ions results into the change of their free volume properties which have strong correlation with their macroscopic properties. Poly-ethylene-oxide (PEO)-salt polymers were prepared using solution-cast method. Irradiation of the films with 95 MeV oxygen (O 6+) ions from the pelletron accelerator at IUAC, New Delhi, India, to different fluences up to 10 13 ions/cm 2 was carried out under high vacuum of the order of 4 × 10 -6 Torr. Nanosized free volume parameters in PEO-salt polymer complex have been studied by positron annihilation lifetime spectroscopy (PALS) and Doppler broadening spectroscopy (DBS). From orthopositronium ( o-Ps) lifetime, free volume hole radius, free volume of micro voids and fractional free volume are computed. Free volume changes with the fluence are studied. The variation of o-Ps lifetime, mean free volume and fractional free volume with the ion fluence is studied. o-Ps lifetime, free volume radius, mean free volume and fractional free volume decrease for the fluence 10 10 and 10 11 ions/cm 2 and then increase with fluences of 10 12 and 10 13 ions/cm 2. The S parameter showed a continuous decrease with increasing fluence of irradiation. The intermediate lifetime ?2 also showed a similar decrease. These results indicate the occurrence of scission in the polymer chains and the fragmentation of larger free volumes into smaller ones.

Kumar, Rajesh; De, Udayan; Nambissan, P. M. G.; Maitra, M.; Ali, S. Asad; Middya, T. R.; Tarafdar, S.; Singh, F.; Avasthi, D. K.; Prasad, Rajendra

2008-04-01

256

Atomic Oscillator Strengths by Emission Spectroscopy and Lifetime Measurements  

NASA Astrophysics Data System (ADS)

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

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

2002-11-01

257

Positron annihilation study on ZnO-based scintillating glasses  

Microsoft Academic Search

Positron lifetime of ZnO-based scintillating glasses (55?x)SiO2–45ZnO–xBaF2 (x=5, 10, 15mol%) were measured with a conventional fast–fast spectrometer. Three positron lifetime components ?1, ?2, and ?3 are ?0.23ns, ?0.45ns, and ?1.6ns, respectively. All the three positron lifetime components first increase with increasing BaF2 concentration from 5mol% to 10mol%, then decreases as BaF2 further increases to 15mol%. The result suggests that the

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

2009-01-01

258

Beam-laser measurements of lifetimes in SiO+ and N+2  

Microsoft Academic Search

We have constructed a beam-laser lifetime-measuring apparatus and tested it by measuring the well known lifetime of the v=0 level of the 2Sigma+u state of 14N+2. Our result of 61.8(5) ns is in excellent agreement with previous high-precision measurements. Employing this technique we performed measurements of the lifetimes of the four lowest vibrational levels of the B 2Sigma+ state of

T. J. Scholl; R. Cameron; S. D. Rosner; R. A. Holt

1995-01-01

259

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

NASA Astrophysics Data System (ADS)

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

Dryzek, Jerzy; Siemek, Krzysztof

2013-12-01

260

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

261

Secondary cosmic-ray electrons and positrons from 1 to 100 GeV in the upper atmosphere and interstellar space, and interpretation of a recent positron flux measurement  

NASA Technical Reports Server (NTRS)

Secondary electron and positron fluxes generated in interstellar space and in the atmosphere from the decays of pions and kaons in inelastic nuclear interactions are calculated by Monte Carlo techniques for lepton energies in the range from 1 to 100 GeV and an assumed thickness of 10 g/sq cm or less for the interstellar or atmospheric material. A simple and accurate analytical model which summarizes the Monte Carlo results and identifies the essential parameters involved is developed and used to interpret a previous positron measurement. It is found that the thickness of interstellar and source material is about 4.3 g/sq cm for cosmic-ray positrons with energies exceeding 4 GeV, a result that is difficult to reconcile with recently proposed two-containment-volume propagation models which predict a thickness of 1.8 g/sq cm for the same energies on the basis of the energy dependence of the measured (Li+Be+B)/(C+O) ratio. It is shown that single-containment-volume (galactic) models invoking an energy-dependent leakage lifetime are compatible with the positron data, but lack a mechanism to explain the energy dependence.

Orth, C. D.; Buffington, A.

1976-01-01

262

Measurement of the charged and neutral D meson lifetimes  

SciTech Connect

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

Butler, J.M.

1986-02-01

263

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

264

Measurements of aperture and beam lifetime using movable beam scrapers in Indus-2 electron storage ring  

SciTech Connect

In this paper, the measurements of vertical and horizontal aperture which are available for stable beam motion in Indus-2 at beam energy 2.5 GeV using movable beam scrapers are presented. These beam scrapers are installed in one of the long straight sections in the ring. With the movement of beam scrapers towards the beam centre, the beam lifetime is measured. The beam lifetime data obtained from the movement of vertical and horizontal beam scrapers are analyzed. The contribution of beam loss due to beam-gas scattering (vacuum lifetime) and electron-electron scattering within a beam bunch (Touschek lifetime) is separated from the measured beam lifetime at different positions of the beam scrapers. Vertical and horizontal beam sizes at scrapers location are estimated from the scraper movement towards the beam centre in quantum lifetime limit and their values closely agree with measured value obtained using X-ray diagnostic beamline.

Kumar, Pradeep; Ghodke, A. D.; Karnewar, A. K.; Holikatti, A. C.; Yadav, S.; Puntambekar, T. A.; Singh, G. [Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)] [Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Singh, P. [Bhabha Atomic Research Centre, Mumbai (India)] [Bhabha Atomic Research Centre, Mumbai (India)

2013-12-15

265

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

NASA Astrophysics Data System (ADS)

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

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.; Åsman, 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.; ?wiok, 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.; Kur?a, 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.

2009-03-01

266

Measurement of the lifetime of excited-state electron bubbles in superfluid helium  

SciTech Connect

We report on the measurement of the lifetime of bubbles in superfluid helium that contain an electron in the 1P state. The 1P bubbles are produced by laser excitation of ground-state bubbles, and are detected by ultrasonic cavitation. Our measurements show that the lifetime of these excited bubbles is much less than the calculated lifetime for radiative decay and, hence, is determined by a nonradiative mechanism.

Ghosh, Ambarish; Maris, Humphrey J. [Department of Physics, Brown University, Providence, Rhode Island 02912 (United States)

2005-08-01

267

Applications of positron annihilation spectroscopy in materials research  

NASA Technical Reports Server (NTRS)

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

Singh, Jag J.

1988-01-01

268

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

269

Subnanometre size free volumes in amorphous Verapamil hydrochloride: a positron lifetime and PVT study through T(g) in comparison with dielectric relaxation spectroscopy.  

PubMed

Positron annihilation lifetime spectroscopy (PALS), a method well established for the study of polymers, is employed to characterize the temperature dependence of the free volume through T(g) in the amorphous pharmaceutical Verapamil hydrochloride. From the PALS spectra analyzed with the routine LifeTime9.0 the size (volume) distribution of local free volumes (subnanometre-size holes), its mean, v(h), and mean dispersion, sigma(h), were calculated. A comparison with the macroscopic volume from PVT-experiments delivered the hole density and the hole free volume fraction and in that way a complete characterization of the free volume microstructure. These data are used in correlation with structural (alpha-) relaxation data from broad-band dielectric spectroscopy in terms of the Cohen-Turnbull free volume model. An extension of this model, distinctions in the free volume behaviour of the glassy and supercooled-liquid state and different ways of extrapolating the equilibrium part of the free volume into the temperature range of the glass are discussed. The potential of the PALS method for the study of pharmaceuticals is briefly reviewed and some recently developed applications (analysis of density fluctuations) are illuminated. PMID:20638474

Dlubek, Günter; Shaikh, Muhammad Q; Rätzke, Klaus; Pionteck, Jürgen; Paluch, Marian; Faupel, Franz

2010-10-01

270

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

National Technical Information Service (NTIS)

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

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

1980-01-01

271

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

272

An Undergraduate Experiment for the Measurement of Phosphorescence Lifetimes  

ERIC Educational Resources Information Center

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

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

1975-01-01

273

Lifetime Measurements in C I, C Ii and C Iii.  

National Technical Information Service (NTIS)

Radiative lifetimes have been obtained by the beam-foil method for twelve excited terms in C1-C3. CO(+) beams with energies between 250 and 1000 keV, incident on 5 mecrog/sq cm carbon foils, were used to excite the terms. Systematic errors due to blends a...

D. L. Mickey

1970-01-01

274

Measurement of the B0 and B+ lifetimes  

Microsoft Academic Search

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

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

1993-01-01

275

Neutron Detection Improvements for Measurement of Neutron Lifetime  

Microsoft Academic Search

Ultra Cold Neutrons (UCN) have energies low enough to be confined in material and magnetic traps, yet it makes transmission into typical neutron detectors a nontrivial task. The neutron lifetime experiment at LANL may require improvements to a standard ionization chamber detector or an entirely different approach to UCN detection [1]. We compare Si and Zr ionization chamber windows to

Gregory Manus; Chen-Yu Liu; Daniel Salvat; Christopher Cude; Aaron Hanson; Sonya Sawtelle

2010-01-01

276

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. Maña; 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

277

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

Microsoft Academic Search

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

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

1995-01-01

278

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

NASA Astrophysics Data System (ADS)

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

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.; Daoudi, M.; de Sangro, R.; de Simone, P.; dell'orso, R.; Dima, M.; Du, P. Y.; 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.; 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.; Müller, 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.; Saxton, O. H.; Schaffner, S. F.; Schalk, T.; Schindler, R. H.; Schneekloth, U.; Schumm, B. A.; Seiden, A.; Sen, S.; Serbo, V. V.; Shaevitz, M. H.; Shank, J. T.; Shapiro, G.; Shapiro, S. L.; Sherden, D. J.; Shmakov, K. D.; Simopoulos, C.; Sinev, N. B.; Smith, S. R.; Snyder, J. A.; Stamer, P.; Steiner, H.; Steiner, R.; Strauss, M. G.; Su, D.; Suekane, F.; Sugiyama, A.; Suzuki, S.; Swartz, M.; Szumilo, A.; Takahashi, T.; Taylor, F. E.; Torrence, E.; Trandafir, A. I.; Turk, J. D.; Usher, T.; Va'vra, J.; Vannini, C.; Vella, E.; Venuti, J. P.; Verdier, R.; Verdini, P. G.; Wagner, S. R.; Waite, A. P.; Watts, S. J.; Weidemann, A. W.; Weiss, E. R.; Whitaker, J. S.; White, S. L.; Wickens, F. J.; Williams, D. A.; Williams, D. C.; Williams, S. H.; Willocq, S.; Wilson, R. J.; Wisniewski, W. J.; Woods, M.; Word, G. B.; Wyss, J.; Yamamoto, R. K.; Yamartino, J. M.; Yang, X.; Yellin, S. J.; Young, C. C.; Yuta, H.; Zapalac, G.; Zdarko, R. W.; Zeitlin, C.; Zhang, Z.; Zhou, J.

1995-11-01

279

Measurement of the positron work functions of polycrystalline Fe, Mo, Ni, Pt, Ti, and V  

NASA Astrophysics Data System (ADS)

We report measurements of the positron work functions ?+ of polycrystalline samples of Fe, Mo, Ni, Pt, Ti, and V. The positron work functions were obtained by measuring the energy spectrum of slow positrons reemitted by the metal surfaces when bombarded with keV-energy positrons. Two methods were used to extract the work functions. The first method provides an absolute measurement. The second method infers the positron work function from measurements of ?=?++?- (where ?+ and ?- are the positron and electron chemical potentials, respectively) relative to the value of ? for Cu and to the values of the electron work function for the surface. The second method (which circumvents many of the systematic problems of the first method since the values of ? are independent of crystal face and surface contamination) gives ?+Fe=-1.2(2) eV, ?+MO=-2.2(2) eV, ?+Ni=-1.2(2) eV, ?+Pt=-1.8(2) eV, ?+V=-0.6(2) eV, and ?+Ti>0. Our results are compared to theoretical predictions and to previous measurements.

Jibaly, Mohammed; Weiss, Alex; Koymen, A. R.; Mehl, D.; Stiborek, L.; Lei, C.

1991-12-01

280

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

NASA Astrophysics Data System (ADS)

Minority carrier lifetime measurement using a microwave photoconductivity decay method was examined. A simple method of immersing a silicon wafer in a toxic HF solution by using a plastic envelope is introduced. An effective lifetime in 50% HF solution is much higher than that in air due to reduction of the surface recombination velocity and is almost the same compared with that of an oxidized and well-passivated substrate. This method provides the effective lifetime, which approximates a bulk lifetime, without an oxide layer and is useful in estimating the short circuit current of solar cells prior to the cell fabrication.

Nammori, Takayuki; Okamoto, Koji; Nunoi, Tohru; Hayashi, Yutaka

1990-01-01

281

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

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

282

A Comparison of the Microwave Photoconductivity Decay and Open-Circuit Voltage Decay Lifetime Measurement Techniques for Lifetime-Enhanced 4H-SiC Epilayers  

NASA Astrophysics Data System (ADS)

This work compares the optical microwave photoconductivity decay (?PCD) and electrical open-circuit voltage decay (OCVD) techniques for measuring the ambipolar carrier lifetime in 4H-silicon carbide (4H-SiC) epitaxial layers. Lifetime measurements were carried out by fabricating P+/intrinsic/N+ (PiN) diodes on 100- ?m-thick, 1 × 1014 cm-3 to 4.5 × 1014 cm-3 doped N-type 4 H-SiC epilayers, and measuring the lifetime optically using ?PCD prior to metallization, then electrically using OCVD after contact deposition. Both as-grown epilayers as well as epilayers with improved lifetime (via thermal oxidation) were measured using both techniques. The observed ambipolar lifetime was improved from 1.4 ?s on an unenhanced wafer to 4 ?s on a wafer enhanced through the oxidation process as measured by ?PCD. Little difference was observed between the ?PCD and OCVD measurements on the unenhanced wafer; the ambipolar lifetime on the enhanced wafer measured by OCVD was approximately 5.5 ?s, or 1.5 ?s higher than the ?PCD measurement. Continuous evaluation of the OCVD transient waveform was necessary due to the high lifetime in the enhanced wafer; shunt resistances included to discharge the P+/N junction capacitance were found to damp the OCVD response and yield low values for the measured lifetime. Simulation of the ?PCD measurement including various surface recombination conditions yielded a good match to experimentally observed ?PCD measurements for high values of the surface recombination velocity. The OCVD lifetime measurement technique is expected to yield measured lifetime values closer to the physical value due to its independence from surface conditions, provided that the experimental conditions are appropriately chosen.

Van Brunt, Edward; Agarwal, Anant; Burk, Al; Cheng, Lin; O'Loughlin, Michael; Palmour, John; Suvorov, Alexander

2014-04-01

283

Measurement of the average B hadron lifetime in Z0 decays  

Microsoft Academic Search

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

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

1992-01-01

284

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

285

Interplay of bulk and surface properties for steady-state measurements of minority carrier lifetimes  

NASA Astrophysics Data System (ADS)

The measurement of the minority carrier lifetime is a powerful tool in the field of semiconductor material characterization as it is very sensitive to electrically active defects. Furthermore, it is applicable to a large variety of samples ranging from ingots to wafers. In this work, a systematic analysis of the effective measurable lifetime within the steady-state approach for samples of arbitrary thickness is presented and applied to experimental data. It is shown how the measured lifetime relates to the intrinsic bulk lifetime for a given material quality, sample thickness, and surface passivation. This approach makes the bulk properties experimentally accessible by separating them from the surface effects. A criterion for a critical sample thickness is given beyond which a lifetime measurement allows deducing the bulk properties for a given surface recombination. It is shown how the surface recombination effects lifetime measurements even for thick blocks. Furthermore, it is demonstrated under what conditions a lifetime measurement on unpassivated samples can give reliable bulk information. These results are of particular interest for semiconductor material diagnostics especially for photovoltaic applications but not limited to this field.

Turek, Marko

2012-06-01

286

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

287

Fast Timing:. Lifetime Measurements with LaBr3(Ce) Scintillators  

NASA Astrophysics Data System (ADS)

The performance of new LaBr3(Ce) crystals for ?-ray detectors provides a new method for measurements the lifetimes of nuclear states in the sub-nanosecond domain. Especially the decay scheme is rather complex, it is possible to perform precise measurements because of the superior energy resolution and excellent time resolution of the LaBr3(Ce) detectors, compared to that of BaF2 scintillators. Two measurements are presented to illustrate the method: one off-line test of the known lifetime of the 21+ state in 152Eu, another in-beam re-determination of the lifetime of the 21+ state in 174Os.

Li, C. B.; Wu, X. G.; He, C. Y.; Zheng, Y.; Li, G. S.; Yao, S. H.; Hu, S. P.; Li, H. W.; Wang, J. L.; Liu, J. J.; Li, X. F.; Lu, J. B.; Ma, Y. J.; Yang, D.; Xu, C.; Sun, J. J.; Qu, W. W.

2013-11-01

288

Lifetime-Measurements of Selectively Excited Molecular Levels  

NASA Astrophysics Data System (ADS)

A synchroneously pumped mode-locked cavity-dumped dye laser, which delivers nearly Fourier-limited output pulses with 20 W peak power, 500 ps pulsewidth and 1.5 GHz spectral bandwidth is used to populate selected rovibronic levels in excited electronic states of alkali molecules. The laser induced fluorescence is filtered through a monochromator and the lifetimes of individual rovibronic levels are determined with the single photon delayed coincidence technique. The influence of different perturbations on the lifetimes is investigated and discussed.Translated AbstractLebensdauermessungen an selektiv angeregten MolekülniveausMit einem synchron gepumpten modengekoppelten Farbstofflaser, der fast Fourierbegrenzte Pulse mit 20 W Spitzenleistung, 500 ps Dauer und 1.5 GHz spektraler Bandbreite liefert, werden einzelne Schwingungs-Rotations-Niveaus in elektronisch angeregten Zuständen von Alkali-Dimeren selektiv bevölkert und ihre Lebensdauern mit Hilfe der Photonenzähltechnik mit verzögerter Koinzidenz gemessen. Der Einfluß verschiedener molekularer Störungen (Prädissoziation, Spin-Bahn-Kopplung) auf die Lebensdauern individueller Niveaus wird untersucht und die daraus gewonnenen Erkenntnisse diskutiert.

Bieniak, B.; Hinske, H. P.; Paulus, H.; Zevgolis, D.; Demtröder, W.

289

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

NASA Astrophysics Data System (ADS)

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

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

2012-02-01

290

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

291

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

292

A Pulsed GaAs Laser System for Semiconductor Carrier Lifetime Measurements.  

National Technical Information Service (NTIS)

An electronic system is described for controlling a semiconductor laser, which is convenient for measuring semiconductor carrier lifetimes of 500 ns or greater by the photoconductive decay method with the laser providing the sample illumination. Particula...

C. R. Kannewurf M. E. Motamedi

1969-01-01

293

Measuring the lifetime of trapped sleptons using the general purpose LHC detectors  

SciTech Connect

In supergravity where the gravitino is the lightest supersymmetric particle, the next-to-lightest supersymmetric particle decays to the gravitino with a naturally long lifetime (10{sup 4}-10{sup 8} s). However, cosmological constraints favor charged slepton next-to-lightest supersymmetric particles with lifetimes below a year as the natural next-to-lightest supersymmetric particle candidate. For this scenario we report a method to accurately determine the slepton lifetime and supersymmetry cross section from observation of the decays of sleptons trapped in the material comprising the main detector (ATLAS, CMS). A measurement of the lifetime to 5% is possible after 3 yr at nominal luminosity and running conditions. This method is sensitive to the cosmologically preferred stau lifetime of {approx}37 days and does not require the use of ancillary trapping volumes or special LHC experiment initiated beam dump requirements.

Pinfold, James L.; Sibley, Logan [Physics Department, University of Alberta, Edmonton, Alberta T6G 2G7 (Canada)

2011-02-01

294

Carrier lifetime measurement in n- 4H-SiC epilayers  

NASA Astrophysics Data System (ADS)

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

Klein, P. B.

2008-02-01

295

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

296

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

SciTech Connect

We present measurements of the lifetimes and polarization amplitudes for B{sub s}{sup 0} {yields} J/{psi}{phi} and B{sub d}{sup 0} {yields} J/{psi} K*{sup 0} decays. Lifetimes of the heavy (H) and light (L) mass eigenstates in the B{sub s}{sup 0} system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time.

Acosta, D.; The CDF Collaboration

2005-04-28

297

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

298

In situ activity of suspended and immobilized microbial communities as measured by fluorescence lifetime imaging.  

PubMed

In this study, the feasibility of fluorescence lifetime imaging (FLIM) for measurement of RNA:DNA ratios in microorganisms was assessed. The fluorescence lifetime of a nucleic acid-specific probe (SYTO 13) was used to directly measure the RNA:DNA ratio inside living bacterial cells. In vitro, SYTO 13 showed shorter fluorescence lifetimes in DNA solutions than in RNA solutions. Growth experiments with bacterial monocultures were performed in liquid media. The results demonstrated the suitability of SYTO 13 for measuring the growth-phase-dependent RNA:DNA ratio in Escherichia coli cells. The fluorescence lifetime of SYTO 13 reflected the known changes of the RNA:DNA ratio in microbial cells during different growth phases. As a result, the growth rate of E. coli cells strongly correlated with the fluorescence lifetime. Finally, the fluorescence lifetimes of SYTO 13 in slow- and fast-growing biofilms were compared. For this purpose, biofilms developed from activated sludge were grown as autotrophic and heterotrophic communities. The FLIM data clearly showed a longer fluorescence lifetime for the fast-growing heterotrophic biofilms and a shorter fluorescence lifetime for the slow-growing autotrophic biofilms. Furthermore, starved biofilms showed shorter lifetimes than biofilms supplied with glucose, indicating a lower RNA:DNA ratio in starved biofilms. It is suggested that FLIM in combination with SYTO 13 represents a useful tool for the in situ differentiation of active and inactive bacteria. The technique does not require radioactive chemicals and may be applied to a broad range of sample types, including suspended and immobilized microorganisms. PMID:17981940

Walczysko, Petr; Kuhlicke, Ute; Knappe, Sabine; Cordes, Christiana; Neu, Thomas R

2008-01-01

299

Lifetime measurements in N III using the beam-foil technique and cascade corrections  

Microsoft Academic Search

Lifetime measurements are reported for several levels in the 2s2p3p, 2s2p3d, 2s2p2, 2p3 configurations of boronlike N III. Beam-foil excitation methods were used with cascade repopulation analyzed by the correlated decay curve ANDC technique. A small but significant J-dependence in the lifetimes of the 3d 4F levels was observed. The experimental lifetimes for the levels in the 2s2p2 and 2p3

P. Bengtsson; L. J. Curtis; M. Henderson; R. E. Irving; S. T. Maniak

1995-01-01

300

Lifetime measurement of fissionable nuclei produced in the development of neutron emission (III) Lifetime of protactinium isotopes  

NASA Astrophysics Data System (ADS)

The lifetime of the 233,232Pa excited nuclei produced in the (d, xnf) reaction on 232Th has been measured by the blocking technique at Ed = 8.0-15.6 MeV. The analysis of the decay time of the 233,232Pa performed in the framework of the statistical model of nuclear reaction and the double-humped fission barrier model was made. Characteristics of the transitional states in the second potential well, in particular, the level density and the second-well depth were determined. It was shown that the fissioning nuclei have no axial and mirror symmetry in the excited second-well state. The probability of the second-well state population for actinide nuclei has been evaluated within the diffusion model.

Eremenko, D. O.; Kordyukevich, V. O.; Platonov, S. Yu.; Fotina, O. V.; Yuminov, O. A.; Giardina, G.; Malaguti, F.; Vannini, G.

1995-02-01

301

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

NASA Astrophysics Data System (ADS)

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; Qi, Ying; Mountziaris, T. J.; Salthouse, Christopher D.

2014-05-01

302

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

PubMed

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. PMID:24880404

Wang, Hongtao; Qi, Ying; Mountziaris, T J; Salthouse, Christopher D

2014-05-01

303

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

304

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

305

Precision Measurements of the {Lambda}{sup +}{sub c} and D{sup 0} Lifetimes  

SciTech Connect

We report new precision measurements of the lifetimes of the {Lambda}{sup +}{sub c} and D{sup 0} from SELEX, the charm hadroproduction experiment at Fermilab. Based upon 1630 {Lambda}{sup +}{sub c} and 10210 D{sup 0} decays we observe lifetimes of {tau}[{Lambda}{sup +}{sub c}]=198.1{+-} 7.0{+-}5.6 fs and {tau}[D{sup 0}]=407.9{+-}6.0{+-}4 .3 fs .

Kushnirenko, A.; Alkhazov, G.; Atamantchouk, A. G.; Balatz, M. Y.; Bondar, N. F.; Cooper, P. S.; Dauwe, L. J.; Davidenko, G. V.; Dersch, U.; Dolgolenko, A. G. (and others)

2001-06-04

306

Measurement of the 7p²Pââ Level Lifetime in Atomic Francium  

Microsoft Academic Search

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

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

1997-01-01

307

Iron contamination in silicon wafers measured with the pulsed MOS capacitor generation lifetime technique  

Microsoft Academic Search

The pulsed MOS capacitor generation lifetime technique is used to determine the iron density in boron-doped silicon wafers. Effective generation lifetimes (?g,eff) are extracted from the Zerbst plots obtained from the measured capacitance-time (C-t) data. Upon thermal heating at 200°C for 5 minutes and quenching to 23°C, iron-boron (Fe-B) pairs dissociate into interstitial iron (Fei) and substitutional boron (B). The

Suat-Eng Tan; Dieter K. Schroder; Motohiro Kohno; Morimasa Miyazaki

2000-01-01

308

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

NASA Astrophysics Data System (ADS)

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

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

2013-10-01

309

Measurement of the average b hadron lifetime in Z 0 decays  

Microsoft Academic Search

A sample of 2610 electron candidates and 2762 muon candidates identified in hadronic Z 0 decays has been used to measure the average b hadron lifetime. These data were recorded with the OPAL detector during 1990 and 1991. Maximum likelihood fits to the distributions of the lepton impact parameters yield an average b hadron lifetime of 10052_2005_Article_BF01474617_TeX2GIFE1.gif tau _b =

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

1993-01-01

310

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

311

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

SciTech Connect

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

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

1995-11-01

312

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

313

Defects in ZnO thin films grown on ScAlMgO4 substrates probed by a monoenergetic positron beam  

Microsoft Academic Search

Zinc oxide (ZnO) thin films grown on ScAlMgO4 substrates were characterized by means of positron annihilation. We measured Doppler broadening spectra of annihilation radiation and photoluminescence spectra for the ZnO films deposited by laser molecular-beam epitaxy and single-crystal ZnO. Although the lifetime of positrons in single-crystal ZnO was close to the lifetime of positrons annihilated from the free state, the

A. Uedono; T. Koida; A. Tsukazaki; M. Kawasaki; Z. Q. Chen; Sf. Chichibu; H. Koinuma

2003-01-01

314

Precision measurement of the ratio of the ?b0 to B lifetimes  

NASA Astrophysics Data System (ADS)

The LHCb measurement of the lifetime ratio of the ?b0 baryon to the B meson is updated using data corresponding to an integrated luminosity of 3.0 fb-1 collected using 7 and 8 TeV centre-of-mass energy pp collisions at the LHC. The decay modes used are ?b0?J/?pK- and B?J/??+K-, where the ?+K- mass is consistent with that of the K(892) meson. The lifetime ratio is determined with unprecedented precision to be 0.974±0.006±0.004, where the first uncertainty is statistical and the second systematic. This result is in agreement with original theoretical predictions based on the heavy quark expansion. Using the current world average of the B lifetime, the ?b0 lifetime is found to be 1.479±0.009±0.010 ps.

Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Caponio, F.; 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.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dorosz, P.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Esen, S.; Falabella, A.; Färber, C.; Farinelli, C.; Farry, S.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; 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.; Giani', S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Hafkenscheid, T. W.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; 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.; 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.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lowdon, P.; Lu, H.; Lucchesi, D.; Luo, H.

2014-06-01

315

On the measured lifetime of light hypernuclei 3?H and 4?H  

NASA Astrophysics Data System (ADS)

A statistical combination of the experimental lifetime estimations available in the literatures is performed for 3?H and 4?H, including several recent measurements. The combined average values of the lifetime for 3?H and 4?H are respectively 216-16+19 ps and 192-18+20 ps with a reduced ?2 of 0.89 and 0.48. A new insight into the lifetime estimation of the HypHI Phase 0 experiment by a Bayesian approach is also presented. In this approach, several different prior distributions including the combination of previous lifetime data and a Jeffrey prior are used. The principal mode and the smallest credible interval at 68% of the posterior distribution, given by the prior belief of the previous measurements, are 217-16+19 ps and 194-18+20 ps respectively for 3?H and 4?H. The two employed approaches have revealed that the lifetime of hypernuclei 3?H and 4?H can be shorter than the ?-hyperon lifetime.

Rappold, C.; Saito, T. R.; Bertini, O.; Bianchin, S.; Bozkurt, V.; Kavatsyuk, M.; Kim, E.; Ma, Y.; Maas, F.; Minami, S.; Nakajima, D.; Özel-Tashenov, B.; Yoshida, K.

2014-01-01

316

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

PubMed

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

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

2012-01-01

317

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

NASA Astrophysics Data System (ADS)

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

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

2012-01-01

318

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

319

Structure of Aqueous Solutions of Acetonitrile Investigated by Acoustic and Positron Annihilation Measurements  

Microsoft Academic Search

We report the results of acoustic and positron annihilation measurements in aqueous solutions of acetonitrile (CH3CN). Hydrophobicity of the solute is discussed, as well as the possibility of describing the title system in terms of hydrophobic solvation. The concept of Levay et al. of calculating the \\

K. Jerie; A. Baranowski; S. Koziol; A. Burakowski

2005-01-01

320

Regional distribution of human cerebral vascular mean transit time measured by positron emission tomography  

Microsoft Academic Search

Cerebral vascular mean transit time (MTT) characterizes the cerebral circulation. MTT has been measured in humans by carotid angiography, x-ray computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). However, regional distribution of MTT has not been investigated in detail. Thus, we investigated regional distribution of normal human MTT. Regional cerebral blood flow (CBF) and cerebral blood

Hiroshi Ito; Iwao Kanno; Kazuhiro Takahashi; Masanobu Ibaraki; Shuichi Miura

2003-01-01

321

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

322

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

323

Recoil Distance Method lifetime measurements via gamma-ray and charged-particle spectroscopy at NSCL  

NASA Astrophysics Data System (ADS)

The Recoil Distance Method (RDM) is a well-established technique for measuring lifetimes of electromagnetic transitions. Transition matrix elements derived from the lifetimes provide valuable insight into nuclear structure. Recent RDM investigations at NSCL present a powerful new model-independent tool for the spectroscopy of nuclei with extreme proton-to-neutron ratios that exhibit surprising behavior. Neutron-rich 18C is one such example, where a small B(E2; 2+1 ? 0+gs) represented a dramatic shift from the expected inverse relationship between the B(E2) and 2+1 excitation energy. To shed light on the nature of this quadrupole excitation, the RDM lifetime technique was applied with the Koln/NSCL plunger. States in 18C were populated by the one-proton knockout reaction of a 19N secondary beam. De-excitation gamma rays were detected with the Segmented Germanium Array in coincidence with reaction residues at the focal plane of the S800 Magnetic Spectrometer. The deduced B(E2) and excitation energy were both well described by ab initio no-core shell model calculations. In addition, a novel extension of RDM lifetime measurements via charged-particle spectroscopy of exotic proton emitters has been investigated. Substituting the reaction residue degrader of the Koln/NSCL plunger with a thin silicon detector permits the study of short-lived nuclei beyond the proton dripline. A proof of concept measurement of the mean lifetime of the two-proton emitter 19Mg was conducted. The results indicated a sub-picosecond lifetime, one order of magnitude smaller than the published results, and validate this new technique for lifetime measurements of charged-particle emitters.

Voss, Philip Jonathan

324

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

SciTech Connect

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

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

2009-01-28

325

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

NASA Astrophysics Data System (ADS)

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

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

2013-01-01

326

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

327

Rapid three-dimensional imaging of defect distributions using a high-intensity positron microbeam  

SciTech Connect

An intense positron microbeam generated by an electron accelerator has been developed for obtaining three-dimensional positron lifetime mappings in a sample to permit visual evaluation of defect distributions. The beam diameter at the sample was 80-100 {mu}m. The counting rate of the positron annihilation {gamma} rays used to measure positron lifetime was as large as 3x10{sup 3} s{sup -1}. Three-dimensional imaging was demonstrated of positron lifetimes in a SiO{sub 2} sample, which was irradiated with ion beams through a mesh mask. The time to obtain a single image (3500 pixels for an area of 2.5x3.5 mm{sup 2}) was 0.5-1 h.

Oshima, N.; Suzuki, R.; Ohdaira, T.; Kinomura, A. [National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Narumi, T.; Uedono, A. [Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan); Fujinami, M. [Department of Applied Chemistry, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8552 (Japan)

2009-05-11

328

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

329

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

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