English
Related papers

Related papers: B -> X_u l nu decay distributions to order alpha_s

200 papers

We present ``state-of-the-art'' theoretical expressions for the triple differential B->X_u l^- nu decay rate and for the B->X_s gamma photon spectrum, which incorporate all known contributions and smoothly interpolate between the…

High Energy Physics - Phenomenology · Physics 2010-11-23 Bjorn O. Lange , Matthias Neubert , Gil Paz

The calculation of partial decay rates in B --> X_u l nu decays at next-to-next-to-leading order (NNLO) in alpha_s and to leading order in 1/m_b is described. New results for the hard function are combined with known results for the jet…

High Energy Physics - Phenomenology · Physics 2008-10-17 Ben D. Pecjak

We study the triple differential distribution of B-> Xu l nu, consistently including all perturbative and non-perturbative effects through O(alphas^2 beta_0) and O(1/mb^3). The Fermi motion is parameterized in terms of a single light-cone…

High Energy Physics - Phenomenology · Physics 2009-02-18 P. Gambino , P. Giordano , G. Ossola , N. Uraltsev

We present theoretical predictions for a few phenomenologically interesting distributions in the semileptonic b->u decays which are affected by Fermi motion. The perturbative effects are incorporated at the one-loop level and appear to be…

High Energy Physics - Phenomenology · Physics 2010-11-23 R. David Dikeman , N. G. Uraltsev

We present an updated next-to-leading order analysis of the B -> X_s gamma branching ratio and photon spectrum, including consistently the effects of Fermi motion in the heavy-quark expansion. For the Standard Model, we obtain B(B -> X_s…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. L. Kagan , M. Neubert

A new class of enhanced non-perturbative corrections to the inclusive B->X_s+gamma decay rate is identified, which contribute first at order Lambda/m_b in the heavy-quark expansion and cannot be described using a local operator product…

High Energy Physics - Phenomenology · Physics 2008-11-26 Seung J. Lee , Matthias Neubert , Gil Paz

The inclusive decay B --> X_u l nu is of much interest because of its potential to constrain the CKM element |V_ub|. Experimental cuts required to suppress charm background restrict measurements of this decay to the shape-function region,…

High Energy Physics - Phenomenology · Physics 2009-01-08 H. M. Asatrian , C. Greub , B. D. Pecjak

We calculate the decay distributions for inclusive B -> X_s gamma and B -> X_u l nu decays in the endpoint region, where radiative corrections are large. The computation is done using effective field theory methods. The matching…

High Energy Physics - Phenomenology · Physics 2011-05-05 Christian W. Bauer , Aneesh V. Manohar

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 compute O(alpha_s^2) QCD corrections to the lepton invariant mass spectrum in the decay b --> u l nu_l, relevant for the determination of the CKM matrix element |V_{ub}|. Our method can also be used to evaluate moments of the lepton…

High Energy Physics - Phenomenology · Physics 2010-11-23 Andrzej Czarnecki , Kirill Melnikov

We resum to next-to-leading order the distribution in the ratio of the invariant hadron mass mX to the total hadron energy EX and the distribution in mX in the semileptonic decays B -> Xu l nu. By expanding our formulas, we obtain the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ugo Aglietti , Giulia Ricciardi , Giancarlo Ferrera

Analytic formulae are given for order alpha_s perturbative QCD corrections to the double differential distribution of the tau lepton energy and the invariant mass of the tau + antineutrino system in semileptonic decays of the bottom quark.…

High Energy Physics - Phenomenology · Physics 2009-10-30 Marek Jezabek , Leszek Motyka

Recently, it was shown that in inclusive B -> Xs l+ l- decay, an angular decomposition provides three independent (q^2 dependent) observables. A strategy was formulated to extract all measurable Wilson coefficients in B -> Xs l+ l- from a…

High Energy Physics - Phenomenology · Physics 2009-08-03 Keith S. M. Lee , Frank J. Tackmann

We report the first complete calculation of the five heavy-to-light hadronic structure functions underlying semi-leptonic heavy-quark decays at next-to-next-to-next-to-leading order ($\mathcal{O}(\alpha_s^3)$) in perturbative QCD. This…

High Energy Physics - Phenomenology · Physics 2026-02-13 Long Chen , Xiang Chen , Xin Guan , Yan-Qing Ma

We resum to next-to-leading order (NLO) the distribution in the light-cone momentum p+ = EX - |pX| and the spectrum in the electron energy, in the semileptonic decays B-> Xu l nu, where EX and pX are the total energy and three-momentum of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ugo Aglietti , Giulia Ricciardi , Giancarlo Ferrera

Perturbative corrections of the order of $\alpha_s$ to inclusive double differential lepton distribution from $b$ quark decay are considered. A perturbative correction to the charged lepton energy spectrum has been calculated for an…

High Energy Physics - Phenomenology · Physics 2011-01-25 Marek Jezabek , Leszek Motyka

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

Details of a recent calculation of O(alpha_s^2) corrections to the decay b -> c,l,nu_l, taking into account the c-quark mass, are described. Construction of the expansion in the mass ratio m_c/m_b as well as the evaluation of new four-loop…

High Energy Physics - Phenomenology · Physics 2008-12-30 Alexey Pak , Andrzej Czarnecki

We review the theoretical understanding of the branching ratio and photon-energy spectrum in B -> Xs gamma decays at next-to-leading order in QCD, including consistently the effects of Fermi motion. For the Standard Model, we obtain B(B ->…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert

Hadron spectra and hadronic moments in the decay $B \to X_s \ell^+ \ell^-$ are calculated taking into account both the short-distance and long-distance contributions in the decay amplitude using a Fermi motion (FM) model to incorporate the…

High Energy Physics - Phenomenology · Physics 2016-08-25 A. Ali , G. Hiller
‹ Prev 1 2 3 10 Next ›