BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Amplitude analysis and measurement of the time-dependent CP asymmetry of B-0 -> (KSKSKS0)-K-0-K-0 decays. Phys. Rev. D, 85(5), 054023–21pp.
Abstract: We present the first results on the Dalitz-plot structure and improved measurements of the time-dependent CP-violation parameters of the process B-0 -> (KSKSKS0)-K-0-K-0 obtained using 468 x 10(6) B (B) over bar decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. The Dalitz-plot structure is probed by a time-integrated amplitude analysis that does not distinguish between B-0 and (B) over bar (0) decays. We measure the total inclusive branching fraction B(B-0 -> (KSKSKS0)-K-0-K-0) = (6.19 +/- 0.48 +/- 0.15 +/- 0.12) x 10(-6), where the first uncertainty is statistical, the second is systematic, and the third represents the Dalitz-plot signal model dependence. We also observe evidence for the intermediate resonant states f(0)(980), f(0)(1710), and f(2)(2010). Their respective product branching fractions are measured to be (2.70(-1.19)(+1.25) +/- 0.36 +/- 1.17) x 10(-6), (0.50(-0.24)(+0.46) +/- 0.04 +/- 0.10) x 10(-6), and (0.54(-0.20)(+0.21) +/- 0.03 +/- 0.52) x 10(-6). Additionally, we determine the mixing-induced CP-violation parameters to be S = -0.94(-0.21)(+0.24) +/- 0.06 and C = -0.17 +/- 0.18 +/- 0.04, where the first uncertainty is statistical and the second is systematic. These values are in agreement with the standard model expectation. For the first time, we report evidence of CP violation in B-0 -> (KSKSKS0)-K-0-K-0 decays; CP conservation is excluded at 3.8 standard deviations including systematic uncertainties.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Search for the Z(1)(4050)(+) and Z(2)(4250)(+) states in (B)over-bar(0) -> chi K-c1(-)pi(+) and B+ -> chi K-c1(S)0 pi(+). Phys. Rev. D, 85(5), 052003–12pp.
Abstract: We search for the Z(1)(4050)(+) and Z(2)(4250)(+) states, reported by the Belle Collaboration, decaying to chi(c1)pi(+) in the decays (B) over bar (0) -> chi K-c1(-)pi(+) and B+ -> chi K-c1(S)0 pi(+) where chi(c1) -> J/psi gamma. The data were collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e(+)e(-) collider operating at center-of-mass energy 10.58 GeV, and correspond to an integrated luminosity of 429 fb(-1). In this analysis, we model the background-subtracted, efficiency-corrected chi(c1)pi(+) mass distribution using the K pi mass distribution and the corresponding normalized K pi Legendre-polynomial moments, and then test the need for the inclusion of resonant structures in the description of the chi(c1)pi(+) mass distribution. No evidence is found for the Z(1)(4050)(+) and Z(2)(4250)(+) resonances, and 90% confidence level upper limits on the branching fractions are reported for the corresponding B-meson decay modes.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Improved limits on B-0 decays to invisible final states and to nu nubar gamma. Phys. Rev. D, 86(5), 051105–8pp.
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.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Exclusive measurements of b -> s gamma transition rate and photon energy spectrum. Phys. Rev. D, 86(5), 052012–16pp.
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.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Study of the reaction e(+)e(-) -> J/psi pi(+)pi(-) via initial-state radiation at BABAR. Phys. Rev. D, 86(5), 051102–9pp.
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.
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