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The most recent determinations of the CKM angle gamma/phi3 by the BABAR Collaboration, using time-integrated observables measured in charged B --> D(*)K(*) decays, are presented.The measurements have been performed on the full sample of 468 million BBbar pairs collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B factory in the years 1999-2007.
Comment: 7 pages, 7 figures, 1 table. Proceedings of CKM2010, the 6th International Workshop on the CKM Unitarity Triangle, University of Warwick, UK, 6-10 September 2010
Comment: ICHEP08 parallel talk. 4 pages, 2 figures
Comment: 4 pages, 2 figures. To appear in the SUSY09 conference proceedings
Comment: 12 pages, 9 figures, Presented at Flavor Physics and CP Violation (FPCP 2012), Hefei, China, May 21-25, 2012
A physics-based device simulation was used to study the charge carrier distribution and the electric field configuration inside simplified two-dimensional models for pixel layouts based on the ATLAS pixel sensor. In order to study the behavior of such detectors under different levels of irradiation, a three-level defect model was implemented into the simulation. Using these models, the number of guard rings, the dead edge width and the detector thickness were modified to investigate their influence on the detector depletion at the edge and on its internal electric field distribution in order to optimize the layout parameters. Simulations indicate that the number of guard rings can be reduced by a few hundred microns with respect to the layout used for the present ATLAS sensors, with a corresponding extension of the active area of the s...
Comment: 7 pages, 13 figures. Presented at the 2004 IEEE Nuclear Science Symposium, October 18-21, Rome, Italy. Accepted for publication by IEEE Transactions on Nuclear Science
Based on the full BaBar data sample, we report improved measurements of the ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or mu. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 +- 0.058 +- 0.042 and R(D*) = 0.332 +- 0.024 +- 0.018, which exceed the Standard Model expectations by 2.0 sigma and 2.7 sigma, respectively. Taken together, our results disagree with these expectations at the 3.4 sigma level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model. We also report the observation of the decay B -> D Tau Nu, with a significance of 6.8 sigma.
We present searches for the rare decay modes D0 to e+e-, D0 to mu+mu- and D0 to e mu in continuum e+e- to cbar c events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468 f^-1. These decays are highly GIM suppressed but may be enhanced in several extensions of the Standard Model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D0 to mu+mu- channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman-Cousins method, we set the following 90% confidence level intervals on the branching fractions: B(D0 to e+e-)<1.7 x 10^-7, B(D0 to mu+mu-) within [0.6, 8.1] x 10^-7, and B(D0 to e mu)<3.3 x 10^-7.
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