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Related papers: Electromagnetic Logarithms in B -> X_s l+ l-

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We calculate the three-loop master integrals of Ref. [1] [arXiv:1709.02160] in analytic form. This allows us to present the fermionic contributions to the $\Delta B=2$ Wilson coefficients of the $B$-$\bar B$ decay matrix in…

High Energy Physics - Phenomenology · Physics 2022-07-06 Artyom Hovhannisyan , Ulrich Nierste

We present the complete analytical result for the two-loop logarithmically enhanced contributions to the high energy asymptotic behavior of the vector form factor and the four-fermion cross section in a spontaneously broken SU(2) gauge…

High Energy Physics - Phenomenology · Physics 2010-11-05 Bernd Jantzen , Johann H. Kühn , Alexander A. Penin , Vladimir A. Smirnov

By means of a heavy-top-quark effective Lagrangian, we calculate the three-loop corrections of O(alpha_s^2 G_F M_t^2) to the H->bb-bar partial decay width of the standard-model Higgs boson with intermediate mass M_H<<2M_t. We take advantage…

High Energy Physics - Phenomenology · Physics 2009-10-30 K. G. Chetyrkin , B. A. Kniehl , M. Steinhauser

We present a search for the radiative leptonic decay B+ -> l+ nu gamma, where l=e,mu, using a data sample of 465 million B-meson pairs collected by the BABAR experiment. In this analysis, we fully reconstruct the hadronic decay of one of…

High Energy Physics - Experiment · Physics 2010-04-12 The BABAR Collaboration , B. Aubert

We perform a measurement of the tau -> l gamma nu anti-nu (l = e, mu) branching fractions for a minimum photon energy of 10 MeV in the tau rest frame, using 431fb^-1 of e^+e^- collisions collected at the center-of-mass energy of the…

High Energy Physics - Experiment · Physics 2015-04-01 The BaBar Collaboration

We present the results of a search for $B^{+}\to\gamma \ell^{+}\nu_{\ell}$, where $\ell = e, \mu$. We use a sample of 232 million $B\bar{B}$ pairs recorded at the $\Upsilon(4S)$ with the BaBar detector at the PEP-II $B$ Factory. We measure…

High Energy Physics - Experiment · Physics 2007-05-23 The BABAR Collaboration , B. Aubert

We present a search for the decay $B^{+} \to \tau^{+} \nu_{\tau}$ in $88.9 \times 10^{6}$ $\Upsilon(4S)$ decays recorded with the BABAR detector at the SLAC $B$-Factory. A sample of semi-exclusive, semi-leptonic B decays ($B^{-} \to D^{0}…

High Energy Physics - Experiment · Physics 2007-05-23 BABAR Collaboration , B. Aubert

Ongoing efforts to reduce the perturbative uncertainty in the B -> Xs gamma decay rate have resulted in a theory estimate to NNLO in QCD. However, a few contributions from multi-parton final states which are formally NLO are still unknown.…

High Energy Physics - Phenomenology · Physics 2025-11-17 Tobias Huber , Michal Poradzinski , Javier Virto

We present the first measurement of the $B^0\to X_{u}^- \ell^+ {\nu_\ell} $ partial branching fraction in the end-point region of the lepton momentum spectrum, above the threshold for $B\to X_c\ell {\nu_\ell}$ decays. The analysis is based…

High Energy Physics - Experiment · Physics 2007-08-14 The BABAR Collaboration , B. Aubert

We calculate nonperturbative ${\cal O}(\Lambda^2_{QCD}/m^2_c)$ corrections to the dilepton invariant mass spectrum and the forward-backward charge asymmetry in $B\to X_se^+e^-$ decay using a heavy quark expansion approach. The method has…

High Energy Physics - Phenomenology · Physics 2016-09-06 G. Buchalla , G. Isidori , S. -J. Rey

We reconsider the calculation of ${\cal O}(\Lambda^2_{QCD}/m^2_b)$ nonperturbative corrections to $\bar B\to X_sl^+l^-$ decay. Our analysis confirms the results of Ali et al. for the dilepton invariant mass spectrum, which were in…

High Energy Physics - Phenomenology · Physics 2009-10-09 Gerhard Buchalla , Gino Isidori

We briefly summarize the current status of perturbative calculations at next-to-next-to-leading-order (NNLO) accuracy in the \bar{B}\to X_s\gamma decay rate as well as that of non-perturbative power-corrections.

High Energy Physics - Phenomenology · Physics 2010-11-02 Thorsten Ewerth

In this paper the next-to-leading order (NLO) corrections to $B_c$ meson exclusive decays to S-wave charmonia and light pseudoscalar or vector mesons, i.e. $\pi$, $K$, $\rho$, and $K^*$, are performed within non-relativistic (NR) QCD…

High Energy Physics - Phenomenology · Physics 2014-02-12 Cong-Feng Qiao , Peng Sun , Deshan Yang , Rui-Lin Zhu

Using the heavy quark effective theory framework put forward by Grinstein and Pirjol we work out predictions for B -> K* l+ l-, l = (e, mu), decays for a softly recoiling K*, i.e., for large dilepton masses sqrt{q^2} of the order of the…

High Energy Physics - Phenomenology · Physics 2014-11-21 Christoph Bobeth , Gudrun Hiller , Danny van Dyk

The following is an overview of the measurements of the CKM matrix elements V_cb and V_ub that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and recent advances in QCD calculations. In…

High Energy Physics - Experiment · Physics 2012-10-02 Vera G. Luth

We briefly discuss the status of the NNLL QCD calculations in the inclusive rare B decay $B \to X_s \ell^+ \ell^-$. Two important ingredients, the two-loop matrix elements of the four quark operator ${\cal O}_2$ and the bremsstrahlung…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Ghinculov , T. Hurth , G. Isidori , Y. -P. Yao

I study bottom quark fragmentation in the Standard Model Higgs decay H->b bbar, within the framework of perturbative fragmentation functions. I resum large collinear logarithms ln(m_H^2/m_b^2) in the next-to-leading logarithmic (NLL)…

High Energy Physics - Phenomenology · Physics 2010-11-05 Gennaro Corcella

We study the semileptonic decays B -> Xs e+ e- and B -> Xs mu+ mu- in generic supersymmetric extensions of the Standard Model. SUSY effects are parameterized using the mass insertion approximation formalism and differences with the…

High Energy Physics - Phenomenology · Physics 2011-05-05 E. Lunghi , A. Masiero , I. Scimemi , L. Silvestrini

We report measurements of the first and second moments of the hadronic invariant mass squared distribution, <M^2_X> and <(M^2_X-<M^2_X>)^2>, in B -> X_c l nu decays for minimum lepton momenta ranging from 0.7 to 1.5 GeV/c in the B meson…

High Energy Physics - Experiment · Physics 2012-08-27 Belle Collaboration

We calculate the differential branching fraction, lepton forward-backward asymmetry and direct CP asymmetry for $B_{d,s}\to\gamma\ell\bar{\ell}$ decays with an energetic photon. We employ factorization methods, which result in rigorous…

High Energy Physics - Phenomenology · Physics 2021-03-19 Martin Beneke , Christoph Bobeth , Yu-Ming Wang