832 research outputs found
Studies of Radiative Penguin B Decays at BaBar
We summarize results on a number of observations of penguin dominated
radiative decays of the B meson. Such decays are forbidden at tree level and
proceed via electroweak loops. As such they may be sensitive to physics beyond
the standard model. The observations have been made at the BaBar experiment at
PEP-II, the asymmetric B factory at SLAC.Comment: 3 pages, 5 figure
QCD corrections to the Wilson coefficients C9 and C10 in two-Higgs doublet models
In this letter we present the analytic results for the two-loop corrections
to the Wilson coefficients C_9(mu_W) and C_10(mu_W) in type-I and type-II
two-Higgs-doublet models at the matching scale mu_W. These corrections are
important ingredients for next-to-next-to-leading logarithmic predictions of
various observables related to the decays B -> X_s l^+ l^- in these models. In
scenarios with moderate values of tan(beta) neutral Higgs boson contributions
can be safely neglected for e,mu. Therefore we concentrate on the contributions
mediated by charged Higgs bosons.Comment: 12 pages, 3 figure
Renormalization of the Cabibbo-Kobayashi-Maskawa Quark Mixing Matrix
We have investigated the present renormalization prescriptions of
Cabibbo-Kobayashi-Maskawa (CKM) matrix. When considering the prescription which
is formulated with reference to the case of zero mixing we find it doesn't
satisfy the unitary condition of the bare CKM matrix. After added a delicate
patch this problem can be solved at one-loop level. In this paper We generalize
this prescription to all loop levels and keep the unitarity of the bare CKM
matrix, simultaneously make the amplitude of an arbitrary physical process
involving quark mixing convergent and gauge independent. We also find that in
order to keep the CKM counterterms gauge independent the unitarity of the bare
CKM matrix must be preserved.Comment: has been revised, 8 pages, 1 figur
Recent developments in radiative B decays
We report on recent theoretical progress in radiative B decays. We focus on a
calculation of logarithmically enhanced QED corrections to the branching ratio
and forward-backward asymmetry in the inclusive rare decay anti-B --> X(s) l+
l-, and present the results of a detailed phenomenological analysis. We also
report on the calculation of NNLO QCD corrections to the inclusive decay anti-B
--> X(s) gamma. As far as exclusive modes are concerned we consider
transversity amplitudes and the impact of right-handed currents in the
exclusive anti-B --> K^* l+ l- decay. Finally, we state results for exclusive B
--> V gamma decays, notably the time-dependent CP-asymmetry in the exclusive B
--> K^* gamma decay and its potential to serve as a so-called ``null test'' of
the Standard Model, and the extraction of CKM and unitarity triangle parameters
from B --> (rho,omega) gamma and B --> K^* gamma decays.Comment: 5 pages, 2 figures. Accepted for publication in the proceedings of
International Europhysics Conference on High Energy Physics (EPS-HEP2007),
Manchester, England, 19-25 Jul 200
Evidence for Bosonic Electroweak Corrections in the Standard Model
We present strong indirect evidence for the contribution of bosonic
electroweak corrections in the Standard Model. Although important conceptually,
these corrections give subleading contributions in current high energy
experiments, and it was previously thought that they are difficult to detect.
We also discuss the separate contribution of the Higgs boson.Comment: 9 pages (LaTeX + 3 PS figures, needs psfig
A New Renormalization Scheme of Fermion Fields in Electroweak Standard Model
This paper has been withdrawn by the author,due a immature idea.Comment: 6 page
Brief review on semileptonic B decays
We concisely review semileptonic B decays, focussing on recent progress on
both theoretical and experimental sides.Comment: 18 pages, 2 figures; version to be published in Mod. Phys. Lett.
New proton polarized structure functions in charged current processes at HERA
Estimates for longitudinal spin asymmetries which single out new polarized
nucleon structure functions in deeply inelastic charged current interactions at
HERA energies are given, exploiting their interpretation in terms of polarized
quark distributions. These asymmetries turn out to be large and allow a
measurement of the new polarized structure functions and ,
which would add valuable tests and information on the spin content of quarks
inside a polarized proton. We also show that single spin asymmetries in neutral
current interactions are very small.Comment: LaTeX, 8 pages, 6 figure
Recombinant factorVIII Fc fusion protein for the prevention and treatment of bleeding in children with severe hemophilia A
This work was supported
by funding from Biogen, including funding for the
editorial and writing support in the the development of
this paper
Higher Order Power Corrections in Inclusive B Decays
We discuss order 1/m_b^4 and 1/m_b^5 corrections in inclusive semileptonic
decay of a meson. We identify relevant hadronic matrix elements of
dimension seven and eight and estimate them using the ground-state saturation
approximation. Within this approach the effects on the integrated rate and on
kinematic moments are estimated. The overall relative shift in V_{cb} turns out
about +0.4% as applied to the existing fits. Similar estimates are presented
for B -> X_s+\gamma decays.Comment: 30 pages, 16 figure
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