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Related papers: Complete O(alpha_s^2) Corrections to Zero-Recoil S…

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Exclusive semileptonic B decays into $D_1$ and $D_2^*$ mesons are investigated including order $\Lambda_{QCD}/m_{c,b}$ corrections using the heavy quark effective theory. At zero recoil, the $\Lambda_{QCD}/m_{c,b}$ corrections can be…

High Energy Physics - Phenomenology · Physics 2011-01-27 Adam K. Leibovich , Zoltan Ligeti , Iain W. Stewart , Mark B. Wise

We present complete O(alpha_s^2) corrections to the decay b-->c+l+nu at the point where the invariant mass of the leptons sqrt{q^2} equals the c quark mass. We use this result, together with previously obtained corrections at the ends of…

High Energy Physics - Phenomenology · Physics 2011-01-25 Andrzej Czarnecki , Kirill Melnikov

We calculate analytically the flavor non-singlet $O(\alpha_s^2)$ massive Wilson coefficients for the inclusive neutral current non-singlet structure functions $F_{1,2,L}^{ep}(x,Q^2)$ and $g_{1,2}^{ep}(x,Q^2)$ and charged current non-singlet…

High Energy Physics - Phenomenology · Physics 2016-08-24 Johannes Blümlein , Giulio Falcioni , Abilio De Freitas

The flavor-changing electromagnetic dipole operator O_7 gives the dominant contribution to the B -> Xs gamma decay rate. We calculate two-loop QCD corrections to its matrix element together with the corresponding bremsstrahlung…

High Energy Physics - Phenomenology · Physics 2013-07-02 I. Blokland , A. Czarnecki , M. Misiak , M. Slusarczyk , F. Tkachov

Taking into account the gluon condensate contributions, the form factors of the semileptonic $B_c^- \to D^{*0}\ell\nu$ transition with $l=\tau, e$ are calculated in the framework of the three point QCD sum rules. The heavy quark effective…

High Energy Physics - Phenomenology · Physics 2008-12-30 N. Ghahramany , R. Khosravi , K. Azizi

We provide upper and lower bounds on the form factors for B -> D, D^* by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to leading order in Lambda_QCD/m_Q and alpha_s. The O(alpha_s^2 beta_0)…

High Energy Physics - Phenomenology · Physics 2016-08-25 Cheng-Wei Chiang , Adam K. Leibovich

We present O(alpha_s^2) corrections to the decay t-->bW in the limit of a very large top quark mass, m_t >> m_W. We find that the O(alpha_s^2) effects decrease the top quark decay width Gamma_t by about 2%: Gamma_t =…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andrzej Czarnecki , Kirill Melnikov

We derive a model-independent upper bound for the axial-vector form factor of the $B\ra D^*$ transition at zero recoil, $F_{B\ra D^*}$. The form factor turns out to be noticeably less than unity. The deviation of $F_{B\ra D^*}$ from unity…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Shifman , N. G. Uraltsev , A. Vainshtein

We set up a zero recoil sum rule to constrain the form factors of the $\Lambda_b \to \Lambda_c$ transition. Our results are compared with the recent lattice calculation for these transitions. We find the same situation as in the case for $B…

High Energy Physics - Phenomenology · Physics 2015-10-21 Thomas Mannel , Danny van Dyk

We consider in detail various theoretical uncertainties of the perturbative predictions for the decay width of $H^0\rightarrow b\overline{b}$ process in the region $50\ GeV< M_H\leq 2M_W$. We calculate the order…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. L. Kataev , V. T. Kim

We calculate the O(alpha_s) corrections to the Z^0-penguin and electroweak box diagrams relevant for non-leptonic Delta F = 1 decays with F = S, B. This calculation provides the complete O(alpha_w alpha_s) and O(alpha_w alpha_s sin^2…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. J. Buras , P. Gambino , U. Haisch

We compute the complete two-loop O(alpha) Wilson coefficients relevant for radiative decays of the B meson in the SM. This is a necessary step in the calculation of the O(alpha alpha_s^n ln^n m_b/M_W) corrections and improves on our…

High Energy Physics - Phenomenology · Physics 2009-11-07 Paolo Gambino , Ulrich Haisch

We utilize inclusive sum rules to construct both upper and lower bounds on the form factors for B to D, D*, rho, pi, omega, K and K* semi-leptonic and radiative decays. We include the leading nonperturbative 1/E corrections and point out…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. Glenn Boyd , Ira Z. Rothstein

We compute the next-to-next-to-leading order (NNLO) QCD corrections to b \to c l \bar \nu_l decay rate at a fully differential level. Arbitrary cuts on kinematic variables of the decay products can be imposed. Our computation can be used to…

High Energy Physics - Phenomenology · Physics 2014-11-18 Kirill Melnikov

We calculate the leading-twist O(alphas^2 beta0) corrections to the B to pi transition form factor f+(0) in light-cone sum rules. We find that, as expected, there is a cancellation between the O(alphas^2 beta0) corrections to fB f+(0) and…

High Energy Physics - Phenomenology · Physics 2015-06-04 Aoife Bharucha

We extend previous computations of the second order QCD corrections to semileptonic b \to c inclusive transitions, to the case where the charged lepton in the final state is massive. This allows accurate description of b \to c \tau \bar…

High Energy Physics - Phenomenology · Physics 2010-03-03 Sandip Biswas , Kirill Melnikov

Heavy quark effective theory can be used to calculate the values of the semileptonic B^(*) -> D^(*) decays in the limit that the heavy quark masses are infinite. We calculate the lowest order chiral corrections, which are of O(1/M^2), from…

High Energy Physics - Lattice · Physics 2009-11-07 Daniel Arndt

The $b \to c$ semileptonic sum rules provide relations between the decay rates of $B \to D^{(*)} \tau\bar\nu$ and $\Lambda_b \to \Lambda_c \tau\bar\nu$. Starting from the heavy quark and zero-recoil limits, we revisit the derivation of the…

High Energy Physics - Phenomenology · Physics 2026-01-16 Motoi Endo , Syuhei Iguro , Satoshi Mishima , Ryoutaro Watanabe

With Wilson quarks, on-shell O($a$) improvement of the lattice QCD action is achieved by including the Sheikholeslami-Wohlert term and two further operators of mass dimension 5, which amount to a mass-dependent rescaling of the bare…

High Energy Physics - Lattice · Physics 2024-02-02 Mattia Dalla Brida , Roman Höllwieser , Francesco Knechtli , Tomasz Korzec , Stefan Sint , Rainer Sommer

We evaluate the O(alpha_em/alpha_s) correction to the rate of B -> X_s gamma decay, i.e. we resum all the 0[ alpha_em ln M_W^2/m_b^2 x (alpha_s ln M_W^2/m_b^2)^n ] corrections for n=0,1,2,... Our calculation differs from the previously…

High Energy Physics - Phenomenology · Physics 2009-10-31 Konrad Baranowski , Mikolaj Misiak