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BABAR Collaboration(Aubert, B. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2013). The BABAR detector: Upgrades, operation and performance. Nucl. Instrum. Methods Phys. Res. A, 729, 615–701.
Abstract: The BABAR detector operated successfully at the PEP-Il asymmetric e(+) e(-) collider at the SLAC National Accelerator Laboratory from 1999 to 2008. This report covers upgrades, operation, and performance of the collider and the detector systems, as well as the trigger, online and offline computing, and aspects of event reconstruction since the beginning of data taking.
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BABAR Collaboration(Aubert, B. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Observation of inclusive D*(+/-) production in the decay of Y(1S). Phys. Rev. D, 81(1), 011102–8pp.
Abstract: We present a study of the inclusive D*(+/-) production in the decay of Y(1S) using (98.6 +/- 0.9) X 10(6) Y(2S) mesons collected with the BABAR detector at the Y(2S) resonance. Using the decay chain Y(2S) -> pi(+)pi Y-(1S), Y(1S) -> D*X-+/-, where X is unobserved, we measure the branching fraction B[Y(1S) -> D*X-+/-] = (2.52 +/- 0.13(stat) +/- 0.15(syst)% and the D*(+/-) momentum distribution in the rest frame of the Y(1S). We find evidence for an excess of D*+/- production over the expected rate from the virtual photon annihilation process Y(1S) -> gamma* -> c (c) over bar -> D*X-+/-.
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BABAR Collaboration(Aubert, B. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Searches for Lepton Flavor Violation in the Decays tau(+/-) -> e(+/-)gamma and tau(+/-) -> mu(+/-)gamma. Phys. Rev. Lett., 104(2), 021802–7pp.
Abstract: Searches for lepton-flavor-violating decays of a tau lepton to a lighter mass lepton and a photon have been performed with the entire data set of (963 +/- 7) x 10(6) tau decays collected by the BABAR detector near the Y(4S), Y(3S) and Y(2S) resonances. The searches yield no evidence of signals and we set upper limits on the branching fractions of B(tau(+/-) -> e(+/-)gamma) < 3.3 X 10(-8) and B(tau(+/-) -> mu(+/-)gamma) < 4.4 X 10(-8) at 90% confidence level.
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BABAR Collaboration(Aubert, B. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Correlated leading baryon-antibaryon production in e(+)e(-) -> c(c)over-bar -> Lambda(+)(c)(Lambda)over-bar(c)(-)X. Phys. Rev. D, 82(9), 091102–8pp.
Abstract: We present a study of 649 +/- 35 e(+)e(-) -> c (c) over bar events produced at root s approximate to 10.6 GeV containing both Lambda(+)(c) baryon and a (Lambda) over bar (-)(c) antibaryon. The number observed is roughly 4 times that expected if the leading charmed hadron types are uncorrelated, confirming an observation by the CLEO Collaboration. We find a 2-jet topology in these events but very few additional baryons, demonstrating that the primary c and (c) over bar are predominantly contained in a correlated baryon-antibaryon system. In addition to the charmed baryons we observe on average 2.6 +/- 0.2 charged intermediate mesons, predominantly pions, carrying 65% of the remaining energy.
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BABAR Collaboration(Aubert, B. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Measurement and interpretation of moments in inclusive semileptonic decays (B)over-bar -> Xcl(nu)over-bar. Phys. Rev. D, 81(3), 032003–25pp.
Abstract: We present results for the moments of observed spectra in inclusive semileptonic B-meson decays to charm hadrons (B) over bar -> X(c)l(-)(nu) over bar. Moments of the hadronic-mass and the combined mass-and-energy spectra for different minimum electron or muon momenta between 0.8 and 1: 9 GeV/c are obtained from a sample of 232 X 10(6) Gamma(4S) -> B (B) over bar events, collected with the BABAR detector at the PEP-II asymmetric-energy B-meson factory at SLAC. We also present a reevaluation of the moments of electron-energy spectra and partial decay fractions B((B) over bar -> X(c)e(-)(nu) over bar) for minimum electron momenta between 0.6 and 1: 5 GeV/c based on a sample of 51 X 10(6) Gamma(4S) -> B (B) over bar events. The measurements are used for the extraction of the total decay fraction, the Cabibbo-Kobayashi-Maskawa (CKM) matrix element vertical bar V-cb vertical bar, the quark masses m(b) and m(c), and four heavy-quark QCD parameters in the framework of a Heavy-Quark Expansion (HQE). We find B((B) over bar -> X(c)l(-)(nu) over bar = (10.64 +/- 0.17 +/- 0.06)% and vertical bar V-cb vertical bar = (42.05 +/- 0.45 +/- 0.70) X 10(-3).
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