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We study the semileptonic decays B -> Xs e+ e-, 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 MSSM results…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Lunghi

Exclusive and inclusive, semileptonic and non-leptonic, charmed decays of the B-meson are investigated in the context of a phenomenological quark model. Bound-state effects are taken care of by adopting a single (model-dependent)…

High Energy Physics - Phenomenology · Physics 2009-10-30 I. L. Grach , I. M. Narodetskii , K. A. Ter-Martirosyan , S. Simula

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

We investigate the relation between the E_gamma spectrum in B->X_s gamma decay and the P+ spectrum in semileptonic B->X_u l nu decay (P+ is the hadronic energy minus the absolute value of the hadronic three-momentum), which provides in…

High Energy Physics - Phenomenology · Physics 2014-11-18 Andre H. Hoang , Zoltan Ligeti , Michael Luke

We investigate rare semileptonic \bar B -> \bar K^* l^+ l^- decays, providing a comprehensive treatment of theoretical uncertainties in the low-q^2 region as needed for interpreting current and future LHCb and B-factory data in terms of the…

High Energy Physics - Phenomenology · Physics 2015-06-12 Sebastian Jäger , Jorge Martin Camalich

The shape of the lepton spectrum in inclusive semileptonic $B\to X\,\ell\,\bar\nu_\ell$ decay is sensitive to matrix elements of the heavy quark effective theory, $\bar\Lambda$ and $\lambda_1$. From CLEO data we extract…

High Energy Physics - Phenomenology · Physics 2014-11-17 Martin Gremm , Anton Kapustin , Zoltan Ligeti , Mark B. Wise

Applying the effective Hamilton for $b\rightarrow sl^+l^-,\;(l=e,\;\mu)$ in the framework of minimal supersymmetric extension of the standard model with local $B-L$ gauge symmetry, we investigate branching ratios and forward-backward…

High Energy Physics - Phenomenology · Physics 2017-01-03 Tai-Fu Feng , Jin-Lei Yang , Hai-Bin Zhang , Shu-Min Zhao , Rong-Fei Zhu

We compute O(alpha_s) and O(alpha_s^n beta_0^{n-1}) (BLM) corrections to the five structure functions relevant for b->q l nu decays and apply the results to the moments of a few distributions of phenomenological importance. We present…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. Aquila , P. Gambino , G. Ridolfi , N. Uraltsev

We compute non-perturbative contributions to b->s l+ l- that are not explicitly suppressed by powers of the b-quark mass. They are proportional to lambda_2 and arise from an interference between the free-quark amplitude and higher order…

High Energy Physics - Phenomenology · Physics 2011-01-27 Jiunn-Wei Chen , Gautam Rupak , Martin J. Savage

Using soft-collinear effective theory we describe at leading order in 1/m_b all the semi-inclusive hadronic B -> XM decays near the endpoint, where an energetic light meson M recoils against an inclusive jet X. We also include the decays…

High Energy Physics - Phenomenology · Physics 2008-11-26 Junegone Chay , Chul Kim , Adam K. Leibovich , Jure Zupan

Two-jet event shape distributions, traditionally studied in the language of perturbative QCD, can be described naturally in soft-collinear effective theory. In this language, we demonstrate factorization of event shape distributions into…

High Energy Physics - Phenomenology · Physics 2010-10-27 Christopher Lee

We study power corrections to the differential thrust, heavy jet mass and C-parameter distributions in the two-jet kinematical region in e^+e^- annihilation. We argue that away from the end-point region, e>> \Lambda_{QCD}/Q, the leading…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. P. Korchemsky , S. Tafat

We discuss the implications of charged lepton energy cut to the hadronic invariant mass spectrum in charmless semileptonic B decays. Charged-lepton energy cut is inevitable in order to remove secondary leptonic events such as b -> c, tau ->…

High Energy Physics - Phenomenology · Physics 2011-02-01 K. K. Jeong , C. S. Kim , Yeong Gyun Kim

The charged lepton spectrum in semileptonic $B\to X_u \ell\bar\nu$ decay near maximal lepton energy receives important corrections from subleading structure functions that are formally suppressed by powers of $\Lambda_{QCD}/m_b$ but are…

High Energy Physics - Phenomenology · Physics 2014-11-17 Adam K. Leibovich , Zoltan Ligeti , Mark B. Wise

We discuss two dedicated observables in exclusive B -> K* l+ l- decay that can be used to study effects of physics beyond the standard model, namely the forward-backward asymmetry in the lepton spectrum and the isospin-asymmetry between…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thorsten Feldmann , Joaquim Matias

The goal of the SIMBA collaboration is to provide a global fit to the available measurements of inclusive B -> X_s gamma and B -> X_u l nu decays. By performing a global fit one is able to simultaneously determine the relevant…

High Energy Physics - Phenomenology · Physics 2013-03-06 Florian U. Bernlochner , Heiko Lacker , Zoltan Ligeti , Iain W. Stewart , Frank J. Tackmann , Kerstin Tackmann

The hadronic invariant mass spectrum for the inclusive charmless semileptonic decay $B\to X_u e \bar\nu_e$ is studied. Particular attention is paid to the region $s_H<m_D^2$, which may be useful for extracting the value of $|V_{ub}|$. The…

High Energy Physics - Phenomenology · Physics 2014-11-17 Adam F. Falk , Zoltan Ligeti , Mark B. Wise

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

We perform infrared factorization of differential rates of radiative and semileptonic inclusive decays of the B meson in the end-point region of photon and charged lepton spectrum, respectively, in the leading heavy quark mass limit. We…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. P. Korchemsky , G. Sterman

We study power corrections to the event shapes in $\e^+\e^--$annihilation in the two jets kinematical region, $e\ll 1$. We argue that for $e \sim \Lambda_{QCD}/Q$ all power corrections of the form $1/\lr{Qe}^n$ have to be taken into account…

High Energy Physics - Phenomenology · Physics 2007-05-23 Sofiane Tafat