|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Study of high-multiplicity three-prong and five-prong tau decays at BABAR. Phys. Rev. D, 86(9), 092010–16pp.
Abstract: We present measurements of the branching fractions of three-prong and five-prong tau decay modes using a sample of 430 million tau lepton pairs, corresponding to an integrated luminosity of 468 fb(-1), collected with the BABAR detector at the PEP-II asymmetric-energy e_e storage rings at SLAC National Accelerator Laboratory. The tau(-) -> (3 pi)(-) eta nu(tau), tau(-) -> (3 pi)(-) omega nu(tau), and tau(-) f(1) (1285)nu(tau) branching fractions are presented, as well as a new limit on the branching fraction of the second-class current decay tau(-) -> pi(-) eta'(958)nu(tau). We search for the decay mode tau(-) -> K- eta'(958)nu(tau) and for five-prong decay modes with kaons, and place the first upper limits on their branching fractions.
|
|
|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., Oyanguren, A., & Villanueva-Perez, P. (2014). Antideuteron production in Upsilon(nS) decays and in e(+)e(-) -> q(q) over bar at root s approximate to 10.58 GeV. Phys. Rev. D, 89(11), 111102–8pp.
Abstract: We present measurements of the inclusive production of antideuterons in e(+)e(-) annihilation into hadrons at approximate to 10.58 GeV center-of-mass energy and in Upsilon(1S, 2S, 3S) decays. The results are obtained using data collected by the BABAR detector at the PEP-II electron-positron collider. Assuming a fireball spectral shape for the emitted antideuteron momentum, we find B(Upsilon(1S) -> (d) over barX) = (2.81 +/- 0.49(stat)-(+0.20)(0.24)(syst)) x 10(-5), B(Upsilon(2S) -> (d) over barX) = (2.64 +/- 0.11(stat)(-0.21)(+0.26)(syst)) x 10(-5), B(Upsilon(3S) -> (d) over barX) = (2.33 +/- 0.15(stat)(-0.28)(+0.31)(syst)) x 10(-5), and sigma(e(+)e(-) -> (d) over barX) = (9.63 +/- 0.41(stat)(-1.01)(+1.17)(syst) fb.
|
|
|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., Oyanguren, A., & Villanueva-Perez, P. (2013). Measurement of CP-violating asymmetries in B-0 -> (rho pi)(0) decays using a time-dependent Dalitz plot analysis. Phys. Rev. D, 88(1), 012003–26pp.
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.
|
|
|
|
BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., Oyanguren, A., & Villanueva-Perez, P. (2013). Search for CP Violation in B-0-<(B-0)over bar> mixing using partial reconstruction of B-0 -> D*(-)Xl(+)nu(l) and a kaon tag. Phys. Rev. Lett., 111(10), 101802–7pp.
Abstract: We present results of a search for CP violation in B-0-(B) over bar (0) mixing with the BABAR detector. We select a sample of B0 -> D*-Xl(+)nu decays with a partial reconstruction method and use kaon tagging to assess the flavor of the other B meson in the event. We determine the CP violating asymmetryA(CP) [N((BB0)-B-0) – N((B-0) over bar (B-0) over bar)]/[N((B-0) over bar (B-0) over bar) + N((BB0)-B-0)] = (0.06 +/- 0.17 +/- 0.38-0.32)%, corresponding to Delta(CP) = 1- vertical bar q/p vertical bar = (0.29 +/- 0.84+1.88-1.61) X 10(-3).
|
|
|
|
BABAR Collaboration(Lees, J. P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Searches for rare or forbidden semileptonic charm decays. Phys. Rev. D, 84(7), 072006–13pp.
Abstract: We present searches for rare or forbidden charm decays of the form X(c)(+) -> h(+/-)l(+/-)l((l)+), where X(c)(+) is a charm hadron (D(+), D(s)(+), or A(c)(+)), h +/- is a pion, kaon, or proton, and l((l)+/-) is an electron or muon. The analysis is based on 384 fb(-1) of e(+)e(-) annihilation data collected at or close to the gamma(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10(-6) and 44 x 10(-6) depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.
|
|
