2,100,505 research outputs found
Supersymmetric constraints from Bs -> mu+mu- and B -> K* mu+mu- observables
We study the implications of the recent LHCb limit and results on Bs ->
mu+mu- and B -> K* mu+mu- observables in the constrained SUSY scenarios. After
discussing the Standard Model predictions and carefully estimating the
theoretical errors, we show the constraining power of these observables in
CMSSM and NUHM. The latest limit on BR(Bs -> mu+mu-), being very close to the
SM prediction, constrains strongly the large tan(beta) regime and we show that
the various angular observables from B -> K* mu+mu- decay can provide
complementary information in particular for moderate tan(beta) values.Comment: 30 pages, 14 figure
Search for Bs -> mu mu and B0 -> mu mu decays in CMS
A search for the rare decays (Bs -> \mu \mu) and (B0 -> \mu\mu) performed in
pp collisions at sqrt{s} = 7 TeV is presented. The data sample, collected by
the CMS experiment at the LHC, corresponds to an integrated luminosity of 1.14
/fb. In both cases the number of events observed after all selection
requirements is consistent with expectations from background and standard model
signal predictions. The resulting upper limits on the branching fractions are
BF(Bs -> \mu\mu) \mu \mu) < 4.6 * 10^{-9} at 95%
confidence level (CL). Furthermore, the combination of the results of the
search for the decay (Bs -> \mu \mu) by the CMS and LHCb experiments is
presented. The combined upper limit is BF < 1.1 * 10^{-8} at 95% CL.Comment: Presented at the 2011 Hadron Collider Physics symposium (HCP-2011),
Paris, France, November 14-18 2011, 3 pages, 5 figur
Strong constraints on the rare decays Bs -> mu+ mu- and B0 -> mu+ mu-
A search for Bs -> mu+ mu- and B0 -> mu+ mu- decays is performed using 1.0
fb^-1 of pp collision data collected at \sqrt{s}=7 TeV with the LHCb experiment
at the Large Hadron Collider. For both decays the number of observed events is
consistent with expectation from background and Standard Model signal
predictions. Upper limits on the branching fractions are determined to be BR(Bs
-> mu+ mu-) mu+ mu-) < 1.0 (0.81) x 10^-9 at
95% (90%) confidence level.Comment: 2+6 pages; 4 figures; Accepted for publication in Physical Review
Letter
Enhancement of Br(B_d -> mu^+mu^-)/Br(B_s -> mu^+mu^-) in Supersymmetric Unified Models
We explain the 2.3 sigma deviation in the recent measurements of the neutral
B mesons decay into muon pairs from the standard model prediction in the
framework of supersymmetric grand unified models using anti-symmetric coupling
as a new source of flavor violation. We show a correlation between the B_d ->
mu^+mu^- decay and the CP phase in the B_d -> J/psi K decay and that their
deviations from the standard model predictions can be explained after
satisfying constraints arising from various hadronic and leptonic rare decay
processes, B-bar{B}, K-bar{K} oscillations data and electric dipole moments of
electron and neutron. The allowed parameter space is typically represented by
pseudoscalar Higgs mass m_A < 1 TeV and tan beta_H (= {v_u}/{v_d}) < 20 for
squark and gluino masses around 2 TeV.Comment: 6 pages, 3 figure
Search for new physics in and
Transitions of the type are flavour changing neutral
current processes where new physics can enter in competing loop diagrams with
respect to the Standard Model contributions. In these decays several
observables sensitive to new physics, and where theoretical uncertainties are
under control, can be constructed. Particularly interesting are the angular
asymmetries in the decay and the measurement of the
branching fraction of the decays . Recent measurements
of these observables and the measurement of the isospin asymmetry in the decays
are presented.Comment: Presented at Flavor Physics and CP Violation (FPCP 2012), Hefei,
China, May 21-25, 201
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