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Author LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P.
Title Searches for violation of lepton flavour and baryon number in tau lepton decays at LHCb Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 724 Issue 1-3 Pages 36-45
Keywords
Abstract Searches for the lepton flavour violating decay tau(-) -> mu(-)mu(+)mu(-) and the lepton flavour and baryon number violating decays tau(-) -> (p) over bar mu(+)mu(-) and tau(-) -> p mu(-)mu(-) have been carried out using proton-proton collision data, corresponding to an integrated luminosity of 1.0 fb(-1), taken by the LHCb experiment at root s = 7 TeV. No evidence has been found for any signal, and limits have been set at 90% confidence level on the branching fractions: B(tau(-) -> mu(-)mu(+)mu(-) < 8.0 x 10(-8), B(tau(-) -> <(p)over bar>mu(+)mu(-)) < 3.3 x 10(-7) and B(tau(-) -> p mu(-)mu(-)) < 4.4 x 10(-7). The results for the tau(-) -> (p) over bar mu(+)mu(-) and tau(-) -> p mu(-)mu(-) decay modes represent the first direct experimental limits on these channels.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: jonathan.harrison@hep.manchester.ac.uk
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000321538300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1686
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Measurement of CP-violating asymmetries in B-0 -> (rho pi)(0) decays using a time-dependent Dalitz plot analysis Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 1 Pages 012003 - 26pp
Keywords
Abstract We present results for a time-dependent Dalitz plot measurement of CP-violating asymmetries in the mode B-0 -> pi(+)pi(-)pi(0). The data set is derived from the complete sample of 471 x 10(6) B (B) over bar meson pairs collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at the SLAC National Accelerator Laboratory operating on the Upsilon(4S) resonance. We extract parameters describing the time-dependent B-0 -> rho pi decay probabilities and CP asymmetries, including C = 0.016 +/- 0.059 +/- 0.036, Delta C = 0.234 +/- 0.061 +/- 0.048, S = 0.053 +/- 0.081 +/- 0.034, and Delta S = 0.054 +/- 0.082 +/- 0.039, where the uncertainties are statistical and systematic, respectively. We perform a two-dimensional likelihood scan of the direct CP-violation asymmetry parameters for B-0 -> rho(+/-)pi(-/+) decays, finding the change in chi(2) between the minimum and the origin (corresponding to no direct CP violation) to be Delta chi(2) = 6.42. We present information on the CP-violating parameter alpha in a likelihood scan that incorporates B-+/- -> rho pi measurements. To aid in the interpretation of our results, statistical robustness studies are performed to assess the reliability with which the true values of the physics parameters can be extracted. Significantly, these studies indicate that alpha cannot be reliably extracted with our current sample size, though the other physics parameters are robustly extracted.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, IN2P3, Lab Annecy Le Vieux Phys Particules LAPP, 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 (up) WOS:000322084100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1492
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P.
Title Search for D-(s)(+) -> pi(+)mu(+)mu(-) and D-(s)(+) -> pi(-)mu(+)mu(+) decays Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 724 Issue 4-5 Pages 203-212
Keywords
Abstract A search for non-resonant D-(s)(+) -> pi(+)mu(+)mu(-) and D-(s)(+) -> pi(-)mu(+)mu(+) decays is performed using protonproton collision data, corresponding to an integrated luminosity of 1.0 fb(-1), at root s = 7 TeV recorded by the LHCb experiment in 2011. No signals are observed and the 90% (95%) confidence level (CL) limits on the branching fractions are found to be B(D+ -> pi(+)mu(+)mu(-)) < 7.3 (8.3) x 10(-8), B(D-s(+) -> pi(+)mu(+)mu(-)) < 4.1 (4.8) x 10(-7), B(D-s(+) -> pi(+)mu(+)mu(-)) < 2.2 (2.5) x 10(-8), B(D-s(+) -> pi(+)mu(+)mu(-)) < 1.2 (1.4) x 10(-7). These limits are the most stringent to date.
Address [Bediaga, I.; De Miranda, J. M.; Rodrigues, F. Ferreira; Massafferri, A.; Nasteva, I.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: ed.greening@cern.ch
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000322358500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1525
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Search for a light Higgs boson decaying to two gluons or s(s)over-bar in the radiative decays of Upsilon(1S) Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 031701 - 7pp
Keywords
Abstract We search for the decay Upsilon(1S) -> A(0), A(0) -> gg or s (s) over bar, where A(0) is the pseudoscalar light Higgs boson predicted by the next-to-minimal supersymmetric Standard Model. We use a sample of (17.6 +/- 0.3) x 10(6) Upsilon(1S) mesons produced in the BABAR experiment via e(+)e(-) -> Upsilon(2S) -> pi(+)pi(-)Upsilon(1S). We see no significant signal and set 90%-confidence-level upper limits on the product branching fraction B(Upsilon(1S) -> gamma A(0)) . B(A(0) -> gg or s (s) over bar ranging from 10(-6) to 10(-2) for A(0) masses in the range 0.5-9.0 GeV/c(2).
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS, LAPP, 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 (up) WOS:000322785400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1549
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.
Title Evidence of B+ -> tau(+)nu decays with hadronic B tags Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 031102 - 9pp
Keywords
Abstract We present a search for the decay B+ -> tau(+)nu using 467.8 x 10(6) B (B) over bar pairs collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We select a sample of events with one completely reconstructed B- in the hadronic decay mode (B- -> D-(*X-)0(-) and B- -> J/psi X-). We examine the rest of the event to search for a B+ -> tau(+)nu decay. We identify the tau(+) lepton in the following modes: tau(+) -> e(+)nu(nu) over bar, tau(+) -> mu(+)nu(nu) over bar, tau(+) -> pi(+)(nu) over bar and tau(+) -> rho(+)(nu) over bar. We find an excess of events with respect to the expected background, which excludes the null signal hypothesis at the level of 3.8 sigma (including systematic uncertainties) and corresponds to a branching fraction value of B(B+ -> tau(+)nu) = (1.83(-0.49)(+0.53)(stat) +/- 0.24(syst)) x 10(-4).
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, CNRS IN2P3, Lab Annecy le Vieux Phys Particules LAPP, 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 (up) WOS:000322916300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1547
Permanent link to this record
 
 
Author LHCb Collaboration (Aaij, R. et al); Oyanguren, A.; Ruiz Valls, P.
Title Differential branching fraction and angular analysis of the decay B-s(0) -> phi mu(+)mu(-) Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 084 - 18pp
Keywords Rare decay; Hadron-Hadron Scattering; B physics; Flavor physics
Abstract The determination of the differential branching fraction and the first angular analysis of the decay B-s(0) -> phi mu(+)mu(-) are presented using data, corresponding to an integrated luminosity of 1.0 fb(-1), collected by the LHCb experiment at root s = 7 TeV. The differential branching fraction is determined in bins of q(2), the invariant dimuon mass squared. Integration over the full q2 range yields a total branching fraction of B(B-s(0) -> phi mu(+)mu(-)) = (7.07(-0.59)(+0.64) +/- 0.17 +/- 0.71) x 10(-7), where the first uncertainty is statistical, the second systematic, and the third originates from the branching fraction of the normalisation channel. An angular analysis is performed to determine the angular observables F-L, S-3, A(6), and A(9). The observables are consistent with Standard Model expectations.
Address [Bediaga, I.; De Miranda, J. M.; Ferreira Rodrigues, F.; Hicheur, A.; Massafferri, A.; Nasteva, I.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil, Email: christoph.langenbruch@cern.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000323202600084 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1634
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Time-integrated luminosity recorded by the BABAR detector at the PEP-II e(+)e(-) collider Type Journal Article
Year 2013 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 726 Issue Pages 203-213
Keywords BABAR; Integrated luminosity; Electron-positron collider; PEP-II
Abstract We describe a measurement of the time-integrated luminosity of the data collected by the BABAR experiment at the PEP-II asymmetric-energy e(+)e(-) collider at the Upsilon(4S), Upsilon(3S), and Upsilon(2S) resonances and in a continuum region below each resonance. We measure the time-integrated luminosity by counting e(+)e(-)-> e(+)e(-) and (for the Upsilon(4S) only) e(+)e(-)->mu(+)mu(-) candidate events, allowing additional photons in the final state. We use data-corrected simulation to determine the cross-sections and reconstruction efficiencies for these processes, as well as the major backgrounds. Due to the large cross-sections of e(+)e(-)-> e(+)e(-) and e(+)e(-)->mu(+)mu(-), the statistical uncertainties of the measurement are substantially smaller than the systematic uncertainties. The dominant systematic uncertainties are due to observed differences between data and simulation, as well as uncertainties on the cross-sections. For data collected on the Upsilon(3S) and Upsilon(2S) resonances, an additional uncertainty arises due to Upsilon -> e(+)e(-)X background. For data collected off the Upsilon resonances, we estimate an additional uncertainty due to time dependent efficiency variations, which can affect the short off-resonance runs. The relative uncertainties on the luminosities of the on-resonance (off-resonance) samples are 0.43% (0.43%) for the Upsilon(4S), 0.58% (0.72%) for the Upsilon(3S), and 0.68% (0.88%) for the Upsilon(2S).
Address [Lees, J. P.; Poireau, V.; Tisserand, V.; Bettoni, D.; Bozzi, C.; Piemontese, L.; Santoro, V.; Passaggio, S.; Robutti, E.; Neri, N.; Morandin, M.; Posocco, M.; Rotondo, M.; Simi, G.; Perez, A.; Walsh, J.; Anulli, E.; Ferrarotto, F.; Gioi, L. Li; Mazzoni, M. A.; Piredda, G.] Univ Savoie, CNRS IN2P3, LAPP, F-74941 A Le Vieux, France, Email: abi@slac.stanford.edu
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000323557200028 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1561
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Production of charged pions, kaons, and protons in e(+)e(-) annihilations into hadrons at root s=10.54 GeV Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 032011 - 26pp
Keywords
Abstract Inclusive production cross sections of pi(+/-), K-+/- and p/(p) over bar per hadronic e(+)e(-) annihilation event are measured at a center-of-mass energy of 10.54 GeV, using a relatively small sample of very high quality data from the BABAR experiment at the PEP-II B-factory at the SLAC National Accelerator Laboratory. The drift chamber and Cherenkov detector provide clean samples of identified pi(+/-), K-+/-, and p/(p) over bar over a wide range of momenta. Since the center-of-mass energy is below the threshold to produce a B (B) over bar pair, with B a bottom-quark meson, these data represent a pure e(+)e(-) -> q (q) over bar sample with four quark flavors, and are used to test QCD predictions and hadronization models. Combined with measurements at other energies, in particular at the Z(0) resonance, they also provide precise constraints on the scaling properties of the hadronization process over a wide energy range.
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
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000323576100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1564
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Search for the rare decays B -> pi l(+)l(-) and B-0 -> eta l(+)l(-) Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 032012 - 16pp
Keywords
Abstract We present the results of a search for the rare flavor-changing neutral-current decays B -> pi l(+)l(-) (pi = pi(+), pi(0) and l = e, mu) and B-0 -> eta l(+)l(-) using a sample of e(+)e(-) -> Upsilon(4S) -> B (B) over bar decays corresponding to 428 fb(-1) of integrated luminosity collected by the BABAR detector. No significant signal is observed, and we set an upper limit on the isospin and lepton-flavor averaged branching fraction of B(B -> pi l(+)l(-)) < 5.9 x 10(-8) and a lepton-flavor averaged upper limit of B(B-0 -> eta l(+)l(-)) < 6.4 x 10(-8), both at the 90% confidence level. We also report 90% confidence level branching fraction upper limits for the individual modes B+ -> pi(+)e(+)e(-), B-0 -> pi(0)e(+)e(-), B-0 -> pi(+)mu(+)mu(-), B-0 -> pi(+)mu(+)mu(-), B-0 -> pi(0)mu(+)mu(-), B-0 -> eta e(+)e(-), and B-0 ->eta mu(+)mu(-).
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, 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
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000323609500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1562
Permanent link to this record
 
 
Author BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P.
Title Precision measurement of the e(+)e(-) -> K+K-(gamma) cross section with the initial-state radiation method at BABAR Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 3 Pages 032013 - 28pp
Keywords
Abstract A precise measurement of the cross section for the process e(+)e(-) -> K+K-(gamma) from threshold to an energy of 5 GeV is obtained with the initial-state radiation (ISR) method using 232 fb(-1) of data collected with the BABAR detector at e(+)e(-) center-of-mass energies near 10.6 GeV. The measurement uses the effective ISR luminosity determined from the e(+)e(-) -> mu(+)mu(-)(gamma)gamma(ISR) process with the same data set. The corresponding lowest-order contribution to the hadronic vacuum polarization term in the muon magnetic anomaly is found to be a(mu)(KK,LO) = (22.93 +/- 0.18(stat) +/- 0.22(syst)) x 10(-10). The charged kaon form factor is extracted and compared to previous results. Its magnitude at large energy significantly exceeds the asymptotic QCD prediction, while the measured slope is consistent with the prediction.
Address [Lees, J. P.; Poireau, V.; Tisserand, V.] Univ Savoie, 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
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes (up) WOS:000323609500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1563
Permanent link to this record