排序方式: 共有36条查询结果,搜索用时 15 毫秒
1.
E. Matsinos J. Guy E. Simopoulou W. Venus P. Allport M. Berggren M. Calicchio T. Coghen A. M. Cooper-Sarkar O. Erriquez N. Giannakopoulos G. T. Jones P. Marage M. M. Mobayyen D. R. O. Morrison S. O'Neale M. A. Parker J. Sacton R. A. Sansum N. Schmitz G. W. Van Apeldoorn K. Varvell A. Vayaki H. Wachsmuth W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,44(1):79-87
Backward proton and pion production is studied in ν and \(\bar v\) charged current interactions in neon. The results are compared with other experiments and theory. The complete backward proton data is compatible with protons produced by reinteractions in the nucleus. However in events with only one proton, muon variables appear correlated to those for the backward proton, as expected by the two-nucleon correlation model. 相似文献
2.
P. Marage M. Aderholz P. Allport N. Armenise J. P. Baton M. Berggren D. Bertrand V. Brisson F. W. Bullock W. Burkot M. Calicchio E. F. Clayton T. Coghen A. M. Cooper-Sarkar O. Erriquez P. J. Fitch G. Gerbier J. Guy F. Hamisi P. O. Hulth G. T. Jones P. Kasper H. Klein R. P. Middleton D. B. Miller M. M. Mobayyen D. R. O. Morrison S. Natali M. Neveu S. W. O'Neale M. A. Parker P. Petiau J. Sacton R. A. Sansum E. Simopoulou C. Vallée K. Varvell A. Vayaki W. Venus H. Wachsmuth J. Wells W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,31(2):191-197
The cross section for coherent production of a single π? meson in charged current antineutrino interactions on neon nuclei has been measured in BEBC to be (175±25) 10?40 cm2/neon nucleus, averaged over the energy spectrum of the antineutrino wide band beam at the CERN SPS; this corresponds to (0.9±0.1) % of the total charged current \(\bar v_\mu \) cross section. The distributions of kinematical variables are in agreement with theoretical predictions based on the PCAC hypothesis and the meson dominance model; in particular, theQ 2 dependence is well described by a propagator containing a massm=(1.35±0.18) GeV. The absolute value of the cross section is also in agreement with the model. This analysis thus provides a test of the PCAC hypothesis in the antineutrino energy range 5–150 GeV. 相似文献
3.
Aubert B Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Palano A Chen GP Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Reinertsen PL Stugu B Abbott B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Clark AR Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kluth S Kolomensky YG Kral JF LeClerc C Levi ME Liu T Lynch G Meyer AB Momayezi M Oddone PJ Perazzo A Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Zisman MS 《Physical review letters》2002,88(10):101805
The branching fractions of the exclusive decays B0-->K(*0)gamma and B+-->K(*+)gamma are measured from a sample of (22.74+/-0.36)x10(6) BB decays collected with the BABAR detector at the PEP-II asymmetric e(+)e(-) collider. We find B (B0-->K(*0)gamma) = [4.23+/-0.40(stat)+/-0.22(syst)]x10(-5), B(B+-->K(*+)gamma) = [3.83+/-0.62(stat)+/-0.22(syst)]x10(-5) and constrain the CP-violating charge asymmetry to be -0.170K(*)gamma)<0.082 at 90% C.L. 相似文献
4.
G. T. Jones R. W. L. Jones B. W. Kennedy S. W. O'Neale H. Klein D. R. O. Morrison P. Schmid H. Wachsmuth F. Hamisi D. B. Miller M. M. Mobayyen S. Wainstein M. Aderholz D. Hantke E. Hoffmann U. F. Katz J. Kern N. Schmitz W. Wittek G. Corrigan G. Myatt D. Radojicic P. N. Shotton S. J. Towers F. W. Bullock S. Burke 《Zeitschrift fur Physik C Particles and Fields》1989,44(3):379-384
Within the framework of the quark-parton model, the quark and anti-quark structure functions of the proton have been measured by fitting them to the distributions of the events in the Bjorkeny variable. The data used form the largest sample of neutrino and antineutrino interactions on a pure hydrogen target available, and come from exposures of BEBC to the CERN wide band neutrino and antineutrino beams. It is found that the ratiod v /u v of valence quark distributions falls with increasing Bjorkenx. In the context of the quark-parton model the results constrain the isospin composition of the accompanying diquark system. Models involving scattering from diquarks are in disagreement with the data. 相似文献
5.
Aubert B Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Palano A Pompili A Chen GP Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Clark AR Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF LeClerc C Levi ME Lynch G Oddone PJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Harrison TJ Hawkes CM Knowles DJ O'Neale SW Penny RC Watson AT 《Physical review letters》2002,88(22):221802
Flavor oscillations of neutral B mesons have been studied in e+e- annihilation data collected with the BABAR detector at center-of-mass energies near the upsilon(4S) resonance. The data sample used for this purpose consists of events in which one B0 meson is reconstructed in a hadronic decay mode, while the flavor of the recoiling B0 is determined with a tagging algorithm that exploits the correlation between the flavor of the heavy quark and the charges of its decay products. From the time development of the observed mixed and unmixed final states, we determine the B0-B-0 oscillation frequency deltamd to be 0.516+/-0.016(stat)+/-0.010(syst) ps-1. 相似文献
6.
G. T. Jones B. W. Kennedy R. P. Middleton S. W. O'Neale A. M. Cooper A. Grant H. Klein J. Mittendorfer D. R. O. Morrison A. Parker P. Schmid H. Wachsmuth F. Hamisi M. M. Mobayyen O. Villalobos-Baillie M. Aderholz L. Deck N. Schmitz W. Wittek G. Corrigan G. Myatt D. Radojicic M. Retter 《Zeitschrift fur Physik C Particles and Fields》1984,25(2):121-127
Data from a neutrino and antineutrino hydrogen experiment with BEBC are used to investigate transverse properties of the produced charged hadrons. Measurements are presented on average transverse momenta of charged pions as functions of Feynman-x and the hadronic mass, on the transverse momentum flow within an event and on jet-related quantities. The main features of the data are well described by the LUND model. The data favour a version of the model in which soft gluon effects are included and the primordial transverse momentum of the quarks in the proton is small. Effects from 1st order QCD (hard gluon emission) are negligible. 相似文献
7.
G. T. Jones B. W. Kennedy S. W. O'Neale K. Böckmann W. Gebel C. Geich-Gimbel B. Nellen A. M. Cooper-Sarkar A. Grant H. Klein D. R. O. Morrison P. Schmid H. Wachsmuth J. S. Chima M. M. Mobayyen M. Talebzadeh O. Villalobos-Baillie M. Aderholz L. Deck N. Schmitz K. L. Wernhard W. Wittek G. Corrigan G. Myatt D. Radojicic B. Saitta J. Wells S. Towers P. Shotton 《Zeitschrift fur Physik C Particles and Fields》1985,27(1):43-52
8.
G. T. Jones R. W. L. Jones B. W. Kennedy S. W. O'Neale H. Klein D. R. O. Morrison P. Schmid H. Wachsmuth D. B. Miller M. M. Mobayyen S. Wainstein M. Aderholz E. Hoffmann U. F. Katz J. Kern N. Schmitz W. Wittek P. Allport G. Myatt D. Radojicic F. W. Bullock S. Burke 《Zeitschrift fur Physik C Particles and Fields》1987,37(1):25-38
Data obtained with the bubble chamber BEBC at CERN are used for the first significant test of Adler's prediction for the neutrino and antineutrino-proton scattering cross sections at vanishing four-momentum transfer squaredQ 2. An Extended Vector Meson Dominance Model (EVDM) is applied to extrapolate Adler's prediction to experimentally accessible values ofQ 2. The data show good agreement with Adler's prediction forQ 2→0 thus confirming the PCAC hypothesis in the kinematical region of high leptonic energy transfer ν>2 GeV. The good agreement of the data with the theoretical predictions also at higherQ 2, where the EVDM terms are dominant, also supports this model. However, an EVDM calculation without PCAC is clearly ruled out by the data. 相似文献
9.
K. Varvell A. M. Cooper-Sarkar M. A. Parker R. A. Sansum M. Aderholz N. Armenise J. P. Baton F. W. Bullock M. Berggren D. Bertrand V. Brisson W. Burkot M. Calcchio E. F. Claytoh T. Coghen O. Erriquez P. J. Fitch G. Gerbier J. Guy P. O. Hulth G. Iaselli G. T. Jones P. Kasper H. Klein C. Kochowski P. Marage M. Mermikides R. P. Middleton D. R. O. Morrison M. M. Mobayyen S. Natali M. Neveu S. Nuzzo S. W. O'Neale P. Petiau A. Petrides F. Ruggieri J. Sacton E. Simopoulou C. Vallee A. Vayaki W. A. Venus H. Wachsmuth J. Wells W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,36(1):1-13
The isoscalar nucleon structure functionsF 2(x, Q 2) andxF 3(x, Q 2) are measured in the range 0<Q 2<64 GeV2, 1.7<W 2<250 GeV2,x<0.7 using ν and \(\bar v\) interactions on neon in BEBC. The data are used to evaluate possible higher twist contributions and to determine their impact on the evaluation of the QCD parameter Λ. In contrast to previous analyses reaching to such lowW 2 values, it is found that a low \(\Lambda _{\overline {MS} } \) value in the neighbourhood of 100 MeV describes the data adequately and that the contribution of dynamical higher twist effects is small and negative. 相似文献
10.
Aubert B Barate R Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Harrison TJ Hawkes CM Knowles DJ 《Physical review letters》2003,90(18):181801
We present a measurement of the branching fraction for the rare decays B-->rhoenu and extract a value for the magnitude of V(ub), one of the smallest elements of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix. The results are given for five different calculations of form factors used to para-metrize the hadronic current in semileptonic decays. Using a sample of 55 x 10(6) BB meson pairs recorded with the BABAR detector at the PEP-II e(+)e(-) storage ring, we obtain B(B0-->rho(-)e(+)nu)=(3.29+/-0.42+/-0.47+/-0.55) x 10(-4) and |V(ub)|=(3.64+/-0.22+/-0.25(+0.39)(-0.56)) x 10(-3), where the uncertainties are statistical, systematic, and theoretical, respectively. 相似文献