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

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We construct operators that describe power corrections in mixed collinear-ultrasoft processes in QCD. We treat the ultrasoft-collinear Lagrangian to O(lambda^2), and heavy-to-light currents involving collinear quarks to O(\lambda) including…

High Energy Physics - Phenomenology · Physics 2014-11-17 Dan Pirjol , Iain W. Stewart

Following the updated measurement of the lepton flavour universality (LFU) ratio R_K in B -> Kll decays by LHCb, as well as a number of further measurements, e.g. R_K* by Belle and B_s -> mu mu by ATLAS, we analyse the global status of new…

High Energy Physics - Phenomenology · Physics 2020-04-22 Jason Aebischer , Wolfgang Altmannshofer , Diego Guadagnoli , Meril Reboud , Peter Stangl , David M. Straub

We study consequences of the non-forward amplitude for the semileptonic baryon decay Lambda_b into Lambda_c which will be measured in detail at LHCb. We obtain a sum rule for the subleading elastic Isgur-Wise (IW) function A(w) that…

High Energy Physics - Phenomenology · Physics 2012-02-22 Frederic Jugeau

We perform a data-driven analysis of new physics (NP) effects in exclusive $b \to s \ell^+\ell^-$ decays in a model-independent effective theory approach with dimension six operators considering scalar, pseudo-scalar, vector and…

High Energy Physics - Phenomenology · Physics 2021-07-09 Aritra Biswas , Soumitra Nandi , Ipsita Ray , Sunando Kumar Patra

Recently it has been shown that symmetries emerging in the heavy quark and large recoil energy limit impose various relations on form factors that parametrise the decay of B mesons into light mesons. These symmetries are broken by…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. Beneke , Th. Feldmann

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

We present the O(alpha_s) corrections to the cross section for the reaction e+e- --> gamma^* --> Q \bar Q in the energy region close to the threshold. We assume that the energy of the reaction is such that both the perturbative expansion in…

High Energy Physics - Phenomenology · Physics 2009-10-30 Andrzej Czarnecki , Kirill Melnikov

The partial decay rate $\Gamma(Z\to b\bar{b})$ is significantly influenced by the mass of the top quark due to electroweak radiative corrections. The leading $\sim m_t^2$ and the next-to-leading contribution $\sim \ln m_t^2$ are known to be…

High Energy Physics - Phenomenology · Physics 2011-04-20 A. Kwiatkowski , M. Steinhauser

We analyse the spin structure of inclusive semileptonic b \to c transitions and the effects of non-standard model couplings on the rates and the spectra. The calculation includes the {\cal O} (\alpha_s) corrections as well as the leading…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. M. Dassinger , R. Feger , T. Mannel

We calculate the contributions arising at order $\alpha_s$ in the QCD sum rule for the spin-symmetry violating universal function $\chi_3(v\cdot v')$, which appears at order $1/m_Q$ in the heavy quark expansion of meson form factors. In…

High Energy Physics - Phenomenology · Physics 2009-10-22 M. Neubert , Z. Ligeti , Y. Nir

We calculate the $\mathcal{O}(\alpha_s)$ QCD corrections to the inclusive $h\to b\bar b$ decay rate in the dimension-6 Standard Model Effective Field Theory (SMEFT). The QCD corrections multiplying the dimension-6 Wilson coefficients which…

High Energy Physics - Phenomenology · Physics 2016-11-09 Rhorry Gauld , Benjamin D. Pecjak , Darren J. Scott

By considering that the weak currents and the electromagnetic current are members of the same SU(3) octet, two sum rules involving leading vector form factors in hyperon semileptonic decays are derived in the limit of exact flavor SU(3)…

High Energy Physics - Phenomenology · Physics 2017-05-24 Ruben Flores-Mendieta , Roberto Padron-Stevens

We derive QCD sum rules for heavy baryons at leading order in $1/m_Q$ and at next-to-leading order in $\alpha_s$. The calculation involves the evaluation of four different perturbative three-loop diagrams which determine the…

High Energy Physics - Phenomenology · Physics 2016-08-24 S. Groote , J. G. Körner , O. I. Yakovlev

We compute the O(\alpha_s^2) contributions to the photon energy spectrum of the inclusive decay \bar{B} -> X_s \gamma associated with the magnetic penguin operator O_7. They are an essential part of the ongoing NNLO calculation of this…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. M. Asatrian , T. Ewerth , A. Ferroglia , P. Gambino , C. Greub

The available data on $|\Delta B| = |\Delta S| = 1$ decays are in good agreement with the Standard Model when permitting subleading power corrections of about 15% at large hadronic recoil. Constraining new-physics effects in…

High Energy Physics - Phenomenology · Physics 2014-10-16 Frederik Beaujean , Christoph Bobeth , Danny van Dyk

We compute the inclusive decay rates $b \to D_s^-(D^{*-}_s) c$ including lowest order QCD corrections on the quark legs, and compare with existing data. Unlike the short distance QCD corrections, that are of higher order, these corrections…

High Energy Physics - Phenomenology · Physics 2016-09-06 R. Aleksan , M. Zito , A. Le Yaouanc , L. Oliver , O. Pene , J. -C. Raynal

At $e^+ \, e^-$ colliders the QED--initial state radiation forms a large part of the radiative corrections. Their precise and fast evaluation is an essential asset for the experiments at LEP, the ILC and the FCC-ee, operating at high…

High Energy Physics - Phenomenology · Physics 2023-11-27 J. Blümlein , A. De Freitas , C. G. Raab , K. Schönwald

We derive new sum rules for the form factors of the $B_c\to J/\psi\, \ell \bar{\nu}_\ell$ semileptonic transitions, employing the vacuum-to-$B_c$ correlation function of the $J/\psi$-interpolating and $b\to c$ weak currents. In the heavy…

High Energy Physics - Phenomenology · Physics 2023-01-25 Marzia Bordone , Alexander Khodjamirian , Thomas Mannel

We present an improved calculation of the $B\to K$ transition form factor with chiral current in the QCD light-cone sum rule (LCSR) approach. Under the present approach, the most uncertain twist-3 contribution is eliminated. And the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Xing-Gang Wu , Tao Huang , Zhen-Yun Fang

We present our results for the NNLL virtual corrections to the matrix elements of the operators O_1 and O_2 for the inclusive process b\to s\ell^+\ell^- in the kinematical region q^2>4m_c^2, where q^2 is the invariant mass squared of the…

High Energy Physics - Phenomenology · Physics 2009-05-20 Christoph Greub , Volker Pilipp , Christof Schüpbach