|   | 
Details
   web
Records
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Improved limits on B-0 decays to invisible final states and to nu nubar gamma Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue 5 Pages 051105 - 8pp
Keywords
Abstract We establish improved upper limits on branching fractions for B-0 decays to final states where the decay products are purely invisible (i.e., no observable final state particles) and for final states where the only visible product is a photon. Within the Standard Model, these decays have branching fractions that are below the current experimental sensitivity, but various models of physics beyond the Standard Model predict significant contributions for these channels. Using 471 x 10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance by the BABAR experiment at the PEP-II e(+)e(-) storage ring at the SLAC National Accelerator Laboratory, we establish upper limits at the 90% confidence level of 2.4 x 10(-5) for the branching fraction of B-0 -> invisible and 1.7 x 10(-5) for the branching fraction of B-0 -> invisible + gamma.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, LAPP, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000309241900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1170
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Exclusive measurements of b -> s gamma transition rate and photon energy spectrum Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue 5 Pages 052012 - 16pp
Keywords
Abstract We use 429 fb(-1) of e(+)e(-) collision data collected at the Gamma(4S) resonance with the BABAR detector to measure the radiative transition rate of b -> s gamma with a sum of 38 exclusive final states. The inclusive branching fraction with a minimum photon energy of 1.9 GeV is found to be B((B) over bar -> X-s gamma) = (3.29 +/- 0.19 +/- 0.48) x 10(-4) where the first uncertainty is statistical and the second is systematic. We also measure the first and second moments of the photon energy spectrum and extract the best-fit values for the heavy-quark parameters, m(b) and mu(2)(pi), in the kinetic and shape function models.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, LAPP, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000309241400005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1171
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Study of the reaction e(+)e(-) -> J/psi pi(+)pi(-) via initial-state radiation at BABAR Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue 5 Pages 051102 - 9pp
Keywords
Abstract We study the process e(+)e(-) -> J/psi pi(+)pi(-) with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BABAR detector at center-of-mass energies 10.58 and 10.54 GeV, and correspond to an integrated luminosity of 454 fb(-1). We investigate the J/psi pi(+)pi(-) mass distribution in the region from 3.5 to 5.5 GeV/c(2). Below 3.7 GeV/c(2) the psi (2S) signal dominates, and above 4 GeV/c(2) there is a significant peak due to the Y(4260). A fit to the data in the range 3.74-5.50 GeV/c(2) yields a mass value 4245 +/- 5(stat) +/- 4(syst) MeV/c(2) and a width value 114(-15)(+16)(stat) +/- 7(syst) MeV for this state. We do not confirm the report from the Belle Collaboration of a broad structure at 4.01 GeV/c(2). In addition, we investigate the pi(+)pi(-) system which results from Y(4260) decay.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, LAPP, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000308641900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1175
Permanent link to this record
 

 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Branching fraction and form-factor shape measurements of exclusive charmless semileptonic B decays, and determination of vertical bar V-ub vertical bar Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue 9 Pages 092004 - 31pp
Keywords
Abstract We report the results of a study of the exclusive charmless semileptonic decays, B-0 -> pi(-)l(+)nu, B+ -> pi(0)l(+)nu, B+ -> omega l(+)nu, B+ -> eta l(+)nu, and B+ -> eta'l(+)nu (l = e or mu) undertaken with approximately 462 X 10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with a loose neutrino reconstruction technique. We obtain partial branching fractions in several bins of q(2), the square of the momentum transferred to the lepton-neutrino pair, for B-0 -> pi(-)l(+)nu, B+ -> pi(0)l(+)nu, B+ -> omega l(+)nu, and B+ -> eta l(+)nu. From these distributions, we extract the form-factor shapes f(+)(q(2)) and the total branching fractions B(B-0 -> pi(-)l(+)nu) = (1.45 +/- 0.04(stat) +/- 0.06(syst)) X 10(-4) (combined pi(-) and pi(0) decay channels assuming isospin symmetry), B(B+ -> omega l(+)nu) = (1.19 +/- 016(stat) +/- 0.09(syst)) X 10(-4) and B(B+ -> eta l(+)nu) = (0.38 +/- 0.05(stat) +/- 0.05(syst)) X 10(-4). We also measure B(B+ -> eta'l(+)nu) = (0.24 +/- 0.08(stat) +/- 0.03(syst)) X 10(-4). We obtain values for the magnitude of the Cabibbo-Kobayashi-Maskawa (KM) matrix element vertical bar V-ub vertical bar by direct comparison with three different QCD calculations in restricted q(2) ranges of B -> pi l(+)nu decays. From a simultaneous fit to the experimental data over the full q(2) range and the FNAL/MILC lattice QCD predictions, we obtain vertical bar V-ub vertical bar = (3.25 +/- 0.31) X 10(-3), where the error is the combined experimental and theoretical uncertainty.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, Lab Annecy le Vieux Phys Particules LAPP, CNRS IN2P3, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000310686300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1201
Permanent link to this record
 

 
Author Bernabeu, J.; Martinez-Vidal, F.; Villanueva-Perez, P.
Title Time reversal violation from the entangled B-0(B)over-bar(0) system Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 064 - 18pp
Keywords Discrete and Finite Symmetries; B-Physics; CP violation
Abstract We discuss the concepts and methodology to implement an experiment probing directly Time Reversal (T) non-invariance, without any experimental connection to CP violation, by the exchange of in and out states. The idea relies on the B-0(B) over bar (0)) entanglement and decay time information available at B factories. The flavor or CP tag of the state of the still living neutral meson by the first decay of its orthogonal partner overcomes the problem of irreversibility for unstable systems, which prevents direct tests of T with incoherent particle states. T violation in the time evolution between the two decays means experimentally a difference between the rates for the time-ordered (l+X, J/psi K-s) and (J/psi K-L, l(-)X) decays, and three other independent asymmetries. The proposed strategy has been applied to simulated data samples of similar size and features to those currently available, from which we estimate the significance of the expected discovery to reach many standard deviations.
Address [Bernabeu, J.] Univ Valencia, Dept Theoret Phys, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000309883600021 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1215
Permanent link to this record