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Related papers: $B^0-\bar{B}^0$ Mixing at Next-to-Leading Order

200 papers

We compute next-to-next-to-leading order QCD corrections to the partonic processes $b\to c \bar{u} d$ and $b\to c \bar{c} s$, which constitute the dominant decay channels in standard model predictions for $B$-meson lifetimes within the…

High Energy Physics - Phenomenology · Physics 2024-07-11 Manuel Egner , Matteo Fael , Kay Schönwald , Matthias Steinhauser

We compute the QCD next-to-leading order matching conditions of the (chromo)-magnetic operators relevant for B\to X_s \gamma in supersymmetric models with minimal flavour violation. The calculation is performed under the assumption that the…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Ciuchini , G. Degrassi , P. Gambino , G. F. Giudice

We compute semi-leptonic $B_s$ decay form factors using Heavy Quark Effective Theory on the lattice. To obtain good control of the $1/m_b$ expansion, one has to take into account not only the leading static order but also the terms arising…

High Energy Physics - Lattice · Physics 2018-04-18 Debasish Banerjee , Mateusz Koren , Hubert Simma , Rainer Sommer

The production of four bottom quarks is an important benchmark channel for Higgs analyses and searches for new physics at the LHC. We report on the calculation of the next-to-leading order QCD corrections to the process pp -> b anti-b b…

High Energy Physics - Phenomenology · Physics 2013-07-23 G. Bevilacqua , M. Czakon , M. Krämer , M. Kubocz , M. Worek

We investigate the behaviour of the perturbative relation between the photon energy spectrum in B -> Xs gamma and the hadronic P+ spectrum in semileptonic B -> Xu l nu decay at high orders in perturbation theory in the "large-beta_0" limit,…

High Energy Physics - Phenomenology · Physics 2009-09-02 Francisco Campanario , Michael Luke , Saba Zuberi

We describe a strategy for a non-perturbative computation of the b-quark mass to leading order in 1/m in the Heavy Quark Effective Theory (HQET). The approach avoids the perturbative subtraction of power law divergencies, and the continuum…

High Energy Physics - Lattice · Physics 2011-01-27 Jochen Heitger , Rainer Sommer

We study the triply heavy baryons $\Omega_{QQQ}$ $(Q=c, b)$ in the QCD sum rules by performing the first calculation of the next-to-leading order (NLO) contribution to the perturbative QCD part of the correlation functions. Compared with…

High Energy Physics - Phenomenology · Physics 2021-08-11 Ren-Hua Wu , Yu-Sheng Zuo , Ce Meng , Yan-Qing Ma , Kuang-Ta Chao

We discuss possible large contributions to B -> X_s gamma, which can occur at the next-to-leading order in supersymmetric models. They can originate from terms enhanced by tan(beta) factors, when the ratio between the two Higgs vacuum…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. Degrassi , P. Gambino , G. F. Giudice

Large logarithmic corrections in $\hat s/p_t^2$ lead to substantial variations in the perturbative predictions for inclusive $W$-plus-dijet processes at the Large Hadron Collider. This instability can be cured by summing the…

High Energy Physics - Phenomenology · Physics 2021-04-28 Jeppe R. Andersen , James A. Black , Helen M. Brooks , Emmet P. Byrne , Andreas Maier , Jennifer M. Smillie

We present an improved calculation of $B\to$ light vector form factors from light-cone sum rules, including one-loop radiative corrections to twist-2 and twist-3 contributions, and leading order twist-4 corrections. The total theoretical…

High Energy Physics - Phenomenology · Physics 2008-11-26 Patricia Ball , Roman Zwicky

The next-to-leading order (NLO) corrections to the BFKL equation in the BLM optimal scale setting are briefly discussed. A striking feature of the BLM approach is rather weak Q^2-dependence of the Pomeron intercept, which might indicate an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Victor T. Kim , Lev N. Lipatov , Grigorii B. Pivovarov

We evaluate in perturbative QCD, up to order $\alpha_s^4$, the mass of the $B_c$. We use the so-called 1S-mass in order to improve the convergence of the perturbative series. Our result is $E(B_c)_{pert} = 6326^{+29}_{-9}$ MeV.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Nora Brambilla , Antonio Vairo

We consider the renormalization-group evolution of the matrix element of $\langle 0| \bar{q}(z)_\beta [z,0]b(0)_\alpha| \bar{B}\rangle$, which can be used to define the distribution amplitudes for $B$ meson and widely applied in studies of…

High Energy Physics - Phenomenology · Physics 2021-10-04 Sheng Lü , Mao-Zhi Yang

We carry out the non-perturbative renormalization of the chromo-magnetic operator in Heavy Quark Effective Theory. At order 1/m of the expansion, the operator is responsible for the mass splitting between the pseudoscalar and vector B…

High Energy Physics - Lattice · Physics 2009-04-21 Damiano Guazzini , Harvey B. Meyer , Rainer Sommer

We postulate a supplemental power counting within the heavy quark effective theory, that results in a small, highly-constrained set of second-order power corrections, compared to the standard approach. We determine all $\bar{B} \to D^{(*)}$…

High Energy Physics - Phenomenology · Physics 2022-12-16 Florian U. Bernlochner , Zoltan Ligeti , Michele Papucci , Markus T. Prim , Dean J. Robinson , Chenglu Xiong

The computation on the lattice of the bag parameter $B_{B_s}$ associated to the $B_s - \bar{B_s}$ mixing amplitude in the Standard Model is presented. The estimation has been made by combining the static limit of HQET and the Neuberger…

High Energy Physics - Lattice · Physics 2008-11-26 B. Blossier

We evaluate the three-loop matching conditions for the dimension-five operators that are relevant for the b -> s gamma decay. Our calculation completes the first out of three steps (matching, mixing and matrix elements) that are necessary…

High Energy Physics - Phenomenology · Physics 2010-04-05 Mikolaj Misiak , Matthias Steinhauser

To leading order in $\alpha_s$, we evaluate the leading and non-leading $1/M_b$ corrections to the $B^*B\pi$ and $B^*B\gamma$ couplings using QCD spectral moment sum rules in the full theory. We find that, for large $M_b$ and contrary to…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. G Dosch , S. Narison

We present lattice QCD results for the matrix elements of $R_2$ and other dimension-7, $\Delta B = 2$ operators relevant for calculations of $\Delta \Gamma_s$, the $B_s-\bar{B}_s$ width difference. We have computed correlation functions…

High Energy Physics - Lattice · Physics 2018-03-29 Christine Davies , Judd Harrison , G Peter Lepage , Christopher Monahan , Junko Shigemitsu , Matthew Wingate

In this contribution, the recent calculation of next-to-next-to-leading order QCD and next-to-leading order electroweak corrections to the decay $B_s\to \mu^+\mu^-$ is reviewed, and a detailed discussion of the uncertainty of the theory…

High Energy Physics - Phenomenology · Physics 2014-06-27 Matthias Steinhauser