Download or read book Rare decays B Xd gamma gamma in the standard model written by Ahmed Ali and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rare decays B Xd gamma in the standard model written by A. Ali and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rare Decays B X D Gamma in the Standard Model written by A. Ali and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rare Decays B becomes Xd gamma in the Standard Model written by Ahmed Ali and published by . This book was released on 1992 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rare decay B K gamma BK in the standard model written by Cesáreo A. Dominguez and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rare Decay B becomes K gamma in the Standard Model written by C. A. Domínguez and published by . This book was released on 1988 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for the Decay D0 gamma gamma and Measurement of the Decay D0 pi 0 pi 0 written by James Paul Morris and published by . This book was released on 2009 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The Standard Model is the best current description of fundamental interactions and particles; however, the Standard Model has certain shortcomings which have driven particle physicists for the last 30 years to search for phenomena which provide evidence for the next theory beyond the Standard Model. To this end, using the BaBar detector, we search for evidence of the rare decay D* -> D0[pi];D0->[gamma][gamma]. The branching fraction of this decay is enhanced up to 200 times the standard model prediction in certain beyond-the-Standard-Model theories. A measurement of a significant branching fraction would provide evidence for a new theory of particle physics. We describe our search for this rare decay and an improved measurement of the associated decay, B(D0-> [pi]0 [pi]0) using an integrated luminosity corresponding to 470.5 fb−1 of e e− data collected by the BaBar detector at the PEP-II asymmetric ee− collider at SLAC from 1999-2007. We place an upper limit of B(D0->[gamma][gamma]) 2.51 X 10−6 at 90% confidence level and find B(D0-[pi]0[pi]0) = (8.4 " 0.1 " 0.4 " 0.3) X 10−4.
Download or read book A Search for the Rare Decay B0 2 gamma gamma written by and published by . This book was released on 2010 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes a search for the rare radiative decay B0 → [gamma][gamma], where the charged congugate mode is implied throughout. These decays are highly suppressed in the Standard Model where the branching fraction is expected to be of order 10-8. In some new physics scenarios this could be enhanced by up to an order of magnitude to 10-7. Therefore an observation of a significant signal above the Standard Model prediction could be a sign of new physics.
Download or read book QCD Corrections to the Rare Decays B Xs l l and B Xd l l in the Standard Model written by Manuel Philipp Walker and published by . This book was released on 2002 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for the Rare Decay B0bar D 0 Gamma written by and published by . This book was released on 2005 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on a search for the rare decay {bar B}° → D*°[gamma], which in the standard model is dominated by W-exchange. The analysis is based on a data sample comprising 87.8 x 106 B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. No significant signal is observed, and an upper limit on the branching fraction of 2.5 x 10−5 at the 90% confidence level is obtained.
Download or read book Physics Reach of Rare B Decays written by and published by . This book was released on 2002 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The author discusses the theoretical and empirical status of b 2!s[gamma], b 2!sl l− decays, as well as their future prospects. I emphasize those observables in rare b-decays which can potentially establish new physics and distinguish between extensions of the Standard Model. He briefly reviews current models of electroweak symmetry breaking, all of which can carry interesting flavor characteristics accessible with b-physics experiments.
Download or read book The Radiative Rare Decays B K K Gamma in the Light Cone QCD Sum Rule Approach written by Abdelkader S. Safir and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radiative B Decays written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We summarize the constraints placed on physics beyond the Standard Model from the recent CLEO observations of the exclusive decay B [yields] K*[gamma] and bound on the inclusive model b [yields] s[gamma].
Download or read book The Radiative Rare Decays B K g K Gamma in the Light Cone QCD Sum Rule Approach written by Abdelkader-Salim Safir and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inclusive Rare B Decays Using Effective Field Theories written by Christian Bauer and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we will discuss several properties of rare decays of ' B' mesons. First we discuss properties of the inclusive radiative decay 'B¢' [right arrow] 'Xs'ã, where 'Xs' stands for any hadronic state containing an 's' quark. We extend previous studies of this decay, which included perturbative corrections to order Ã's' and nonperturbative contributions up to order ([Lambda]QCD/' mb')2 and calculate the O ([Lambda]QCD/'mb')3 contributions to this decay. The values of the nonperturbative parameters entering at this order are unknown, leading to uncertainties in the standard model prediction of this decay. We estimate the size of these nonperturbative uncertainties by varying these parameters in the range suggested by dimensional analysis. We also estimate uncertainties arising from a cut on the photon energy which is required experimentally. Another decay mode investigated is 'B¢' [right arrow] ' Xs'3⁄4+3⁄4-. We study the O ([Lambda]QCD/'mb')3 contributions to the leptonic invariant mass spectrum, the forward-backward asymmetry and hadronic invariant mass moments and estimate the resulting uncertainties. We calculate how the size of these uncertainties depend on the value of an experimental cut that has to be applied to eliminate the large background from other 'B' decays. A model independent way to determinate the CKM matrix element @' Vub'@ from the dilepton invariant mass spectrum of the inclusive decay B[right arrow]Xu3⁄4+ n is presented next. We show that cuts required to eliminate the charm background still allow for a theoretically clean way to determine the CKM matrix element @'Vub'@. We also discuss the utility of the 'B¢' [right arrow] 'Xs'3⁄4 +3⁄4- decay rate above the y (2'S') resonance to reduce the resulting uncertainties. Finally, we introduce a novel effective theory valid for highly energetic particles. In decays where the phase space is sufficiently restricted such that final state particles have very high energies compared to their mass, the perturbative as well as nonperturbative series diverge. The effective theory presented allows to sum perturbative Sudakov logarithms in a framework that also incorporates the nonperturbative physics in such limits of phase space.
Download or read book A Search for the Rare Decay B rightarrow gamma gamma written by and published by . This book was released on 2011 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the result of a search for the rare decay B° 2![gamma][gamma] in 426 fb−1 of data, corresponding to 226 million B°{bar B}° pairs, collected on the [Upsilon](4S) resonance at the PEP-II asymmetric-energy ee− collider using the BABAR detector. We use a maximum likelihood fit to extract the signal yield and observe 2112{sup +13} signal events with a statistical signficance of 1.9 [sigma]. This corresponds to a branching fraction [Beta](B° 2![gamma][gamma]) = (1.7 ± 1.1(stat.) ± 0.2(syst.)) x 10−7. Based on this result, we set a 90% confidence level upper limit of [Beta](B° 2![gamma][gamma])
Download or read book Rare B decays in the standard model written by Ahmed Ali and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
