Records |
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 |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000309241400005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number ![sorted by Call Number field, descending order (down)](img/sort_desc.gif) |
IFIC @ pastor @ |
Serial |
1171 |
Permanent link to this record |
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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 |
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Thesis |
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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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 ![sorted by Call Number field, descending order (down)](img/sort_desc.gif) |
IFIC @ pastor @ |
Serial |
1175 |
Permanent link to this record |
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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 |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
|
Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1550-7998 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000310686300001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number ![sorted by Call Number field, descending order (down)](img/sort_desc.gif) |
IFIC @ pastor @ |
Serial |
1201 |
Permanent link to this record |
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Author |
BABAR Collaboration (Lees, J.P. et al); Bernabeu, J.; Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P. |
Title |
Observation of Time-Reversal Violation in the B-0 Meson System |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
109 |
Issue |
21 |
Pages |
211801 - 8pp |
Keywords |
|
Abstract |
Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B-0 or (B) over bar (0)), and J/psi K-L(0) or c (c) over barK(S)(0) final states (referred to as B+ or B-), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, (B) over bar (0) -> B- and B- -> (B) over bar (0), as a function of the time difference between the two B decays. Using 468 X 10(6) B (B) over bar pairs produced in Y(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding Delta S-T(+) = -137 +/- 0.14(stat) +/- 0.06(syst) and Delta S-T(-) = 1.17 +/- 0.18(stat) +/- 0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation. |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, LAPP, F-74941 Annecy Le Vieux, France |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9007 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
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Conference |
|
Notes |
WOS:000311283800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number ![sorted by Call Number field, descending order (down)](img/sort_desc.gif) |
IFIC @ pastor @ |
Serial |
1220 |
Permanent link to this record |
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|
Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A. |
Title |
Search for resonances decaying to eta(c)pi(+) pi(-) in two-photon interactions |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
86 |
Issue |
9 |
Pages |
092005 - 10pp |
Keywords |
|
Abstract |
We report a study of the process gamma gamma -> X -> eta(c)pi(+)pi(-) , where X stands for one of the resonances chi(c2)(1P), eta(c)(2S), X(3872), X(3915), or chi(c2)(2P). The analysis is performed with a data sample of 473.9 fb(-1) collected with the BABAR detector at the PEP-II asymmetric-energy electron-positron collider. We do not observe a significant signal for any channel, and calculate 90% confidence-level upper limits on the products of branching fractions and two-photon widths Gamma B-x ->gamma gamma(X -> eta(c)pi(+) pi(-)): 15.7 eV for chi(c2)(1P), 133 eV for eta(c)(2S), 11.1 eV for X(3872) (assuming it to be a spin-2 state), 16 eV for X(3915) (assuming it to be a spin-2 state), and 18 eV for chi(c2)(2P). We also report upprt limits on the rations of branching fractions B(eta(c)(2S) -> eta(c)pi(+) pi(-))/B(eta(c)(2S) -> (KSK+)-K-0 pi(-)) < 10.0 and B(chi(c2)(1P) -> eta(c)pi(+) pi(-))/B(chi(c2)(1P) -> (KSK+)-K-0 pi(-)) < 32.9 at the 90% confidence level. |
Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, Lab Annecy le Vieux Phys Particules LAAP, 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 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1550-7998 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000310845200002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number ![sorted by Call Number field, descending order (down)](img/sort_desc.gif) |
IFIC @ pastor @ |
Serial |
1225 |
Permanent link to this record |