English
Related papers

Related papers: Comparative analysis of non-perturbative effects i…

200 papers

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

It has recently been pointed out that a new class of subleading shape functions involving B-meson matrix elements of non-local four-quark operators contributes at order Lambda_{QCD}/m_b to B->X_u+l+nu decay distributions in the endpoint…

High Energy Physics - Phenomenology · Physics 2009-01-07 Matthias Neubert

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

This article explores the calculation of non-perturbative parameters present in the matrix element of semileptonic inclusive $B$ decays. These are important for the inclusive determination of the Cabbibo-Kobayashi-Maskawa (CKM) parameters…

High Energy Physics - Phenomenology · Physics 2024-10-30 Namit Mahajan , Dayanand Mishra

Methods are described in the framework of light-cone expansion which allow one to determine the Cabibbo-Kobayashi-Maskawa matrix elements |V_ub| and |V_cb| from measurements of the differential decay rates as a function of the scaling…

High Energy Physics - Phenomenology · Physics 2009-10-31 Changhao Jin

We present an analysis of the Belle measured moments of the lepton energy and hadronic mass spectra in B -> X_c l nu decays and the photon energy spectrum in B -> X_s gamma decays using theoretical expressions derived in the 1S and kinetic…

High Energy Physics - Experiment · Physics 2019-08-14 K. Abe

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

The Cabibbo-Kobayashi-Maskawa matrix element |V_ub| can be extracted from the rate for the semi-leptonic decay B -> pi + l + antineutrino_l, with little theoretical uncertainty, provided the hadronic form factor for the B -> pi transition…

High Energy Physics - Phenomenology · Physics 2016-09-06 Joao M. Soares

We derive the triply differential spectrum for the inclusive rare decay B -> Xs l+ l- in the shape function region, in which Xs is jet-like with $mX^2 \lesssim mb \Lambda_QCD$. Experimental cuts make this a relevant region. The perturbative…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith S. M. Lee , Iain W. Stewart

It is shown that measuring the lepton invariant mass spectrum in inclusive semileptonic B -> X_u l nu decay yields a model independent determination of |V_{ub}|. Unlike the lepton energy and hadronic invariant mass spectra, nonperturbative…

High Energy Physics - Phenomenology · Physics 2010-11-23 Christian W. Bauer , Zoltan Ligeti , Michael Luke

We derive a class of formulae relating moments of B -> Xu l nu to B -> Xs gamma in the shape function region, where m_X^2 ~ m_b Lambda_QCD. We also derive an analogous class of formulae involving the decay B -> Xs l+ l-. These results…

High Energy Physics - Phenomenology · Physics 2008-12-16 Keith S. M. Lee

We present a new theoretical framework for the study of $B\to X_u \ell \nu$ decays, which includes all known perturbative and non-perturbative contributions and a description of leading and subleading Fermi motion effects. The perturbative…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Giordano

The total B->Xs gamma decay rate and the CKM-matrix element Vub play an important role in finding indirect evidence for new physics affecting the flavor sector of the Standard Model, complementary to direct searches at the LHC and Tevatron.…

High Energy Physics - Phenomenology · Physics 2011-05-18 Florian U. Bernlochner , Heiko Lacker , Zoltan Ligeti , Iain W. Stewart , Frank J. Tackmann , Kerstin Tackmann

The effects of spectator light quark in decays of heavy mesons are considered, which vanish in the limit of factorization of matrix elements of four-quark operators over the mesons. These effects include the difference of the total widths…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. B. Voloshin

We present a QCD-based approach to the endpoint region of the lepton spectrum in $\bar B\to X_u\,\ell\,\bar\nu$ decays. We introduce a genuinely nonperturbative form factor, the shape function, which describes the fall-off of the spectrum…

High Energy Physics - Phenomenology · Physics 2010-11-01 Matthias Neubert

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

An analytic result for the O(alpha_s corrections to the triple differential B -> X_u l nu decay rate is presented, to leading order in the heavy-quark expansion. This is relevant for computing partially integrated decay distributions with…

High Energy Physics - Phenomenology · Physics 2015-06-25 F. De Fazio , M. Neubert

We discuss nonperturbative contributions to the inclusive rare $B$ decays $B\to X_s\gamma$ and $B\to X_s\ell^+\ell^-$. We employ an operator product expansion and the heavy quark effective theory to compute the leading corrections to the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Adam F. Falk , Michael Luke , Martin J. Savage

We present the results of a nonrelativistic constituent quark model study of the semileptonic decays $\Lambda_b^0 \to \Lambda_c^+ l^- {\bar \nu}_l$ and $\Xi_b^0 \to \Xi_c^+ l^- {\bar \nu}_l$. We work on coordinate space, with baryon wave…

Nuclear Theory · Physics 2009-11-10 C. Albertus , E. Hernandez , J. Nieves

Using methods of effective field theory, factorized expressions for arbitrary B -> X_u l nu decay distributions in the shape-function region of large hadronic energy and moderate hadronic invariant mass are derived. Large logarithms are…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. W. Bosch , B. O. Lange , M. Neubert , G. Paz
‹ Prev 1 2 3 10 Next ›