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Related papers: The b -> s gamma decay revisited

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The charged-Higgs contributions to the decay \bar{B} -> X_s gamma are discussed in the minimal supersymmetric standard model at large tan beta. These contributions receive two-loop O(alpha_s tan beta) corrections by squark-gluino subloops,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Francesca Borzumati , Christoph Greub , Youichi Yamada

We establish logarithmic local energy decay for wave equations with a varying wavespeed in dimensions two and higher, where the wavespeed is assumed to be a short range perturbation of unity with mild radial regularity. The key ingredient…

Analysis of PDEs · Mathematics 2025-09-12 Gayana Jayasinghe , Katrina Morgan , Jacob Shapiro , Mengxuan Yang

We set up a suitable renormalization programme for the one-loop computation of the decay rate Gamma(H==>hh) in the Minimal Supersymmetric extension of the Standard Model. We then perform an explicit diagrammatic calculation, including the…

High Energy Physics - Phenomenology · Physics 2011-01-27 A. Brignole , F. Zwirner

In this work we propose the Z -> gamma gamma decay as a process strictly forbidden in the standard model, suitable for the search of noncommutativity of coordinates at very short distances. We computed the Z -> gamma gamma partial width in…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Buric , D. Latas , V. Radovanovic , J. Trampetic

The factorization properties of the radiative decays B->V gamma are analyzed at leading order in 1/m_b using the soft-collinear effective theory. It is shown that the decay amplitudes can be expressed in terms of a B->V form factor…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Becher , Richard J. Hill , Matthias Neubert

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 study the effect of resumming large logarithms in the determination of the bottom quark mass through a non-relativistic sum rule analysis. Our result is complete at next-to-leading-logarithmic accuracy and includes some known…

High Energy Physics - Phenomenology · Physics 2008-11-26 Antonio Pineda , Adrian Signer

We present a calculation of the effective weak Hamiltonian which governs $b \rightarrow s\, \gamma$ and $b \rightarrow s \, g$ transitions in two different renormalization schemes (NDR and HV). In the leading logarithmic approximation, we…

High Energy Physics - Phenomenology · Physics 2011-04-20 M. Ciuchini , E. Franco , G. Martinelli , L. Reina , L. Silvestrini

The Bs to mu mu gamma decay offers sensitivity to a wider set of effective operators than its non-radiative counterpart Bs to mu mu, and a set that is interesting in the light of present-day discrepancies in flavour data. On the other hand,…

High Energy Physics - Phenomenology · Physics 2017-03-09 Francesco Dettori , Diego Guadagnoli , Meril Reboud

We review the first measurements of the CKM angle gamma from LHCb. These measurements have been performed with b-hadron decays dominated by b -> u and b -> c tree-level amplitudes, from which gamma can be determined without theoretical…

High Energy Physics - Experiment · Physics 2015-06-15 Stefania Ricciardi

The decay B_s -> mu^+ mu^- in the Standard Model is generated by the well-known W-box and Z-penguin diagrams that give rise to an effective quark-lepton operator Q_A at low energies. We compute QCD corrections of order alpha_s^2 to its…

High Energy Physics - Phenomenology · Physics 2014-03-18 Thomas Hermann , Mikolaj Misiak , Matthias Steinhauser

The measurements of the $\gamma\gamma$ and $b \bar b$ partial decay widths of an intermediate-mass Standard Model Higgs boson are among the most important goals of a future photon linear collider. While in an initially polarized $J_z=0$…

High Energy Physics - Phenomenology · Physics 2011-01-25 Michael Melles , W. James Stirling

We find some errors in previous calculation of leading log QCD corrections to $b \to s\gamma $ decay, which include corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. The inclusive decay rate is found to…

High Energy Physics - Phenomenology · Physics 2016-08-14 Cai-Dian Lü , Jing-Liang Hu , Chong-Shou Gao

We calculate the next-to-leading corrections to the branching ratio of exclusive $B\to K^* \gamma$ decay. The renormalization scale dependence is reduced compared to the leading logarithmic result but there remains a dependence on a cutoff…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. H. Asatryan , H. M. Asatrian , D. Wyler

We calculate next-to-leading QCD corrections to the decay $H^+ \to u\bar d$ for generic up and down quarks in the final state. A recently developed algorithm for evaluation of massive two-loop Feynman diagrams is employed to calculate…

High Energy Physics - Phenomenology · Physics 2016-09-01 Andrzej Czarnecki , Andrei I. Davydychev

We re-examine the question of measuring the weak phase gamma in B -> K pi pi decays. To this end, we express all B -> K pi pi amplitudes in terms of diagrams. We show that, as in B -> K pi, there exist relations between certain tree and…

High Energy Physics - Phenomenology · Physics 2013-05-29 Maxime Imbeault , Nicolas Rey-Le Lorier , David London

Using techniques in logarithmic geometry, we construct a logarithmic analogue of the Fulton--MacPherson configuration spaces. We similarly construct a logarithmically smooth degeneration of the Fulton--MacPherson configuration spaces. Both…

Algebraic Geometry · Mathematics 2026-05-22 Siao Chi Mok

We prove that in the limit $m_b, m_c\to\infty$ with $m_c/m_b$ fixed, factorization holds at order $\alpha_s$ for the decay $\Lambda_b^0\to\Lambda_c^+\pi^-$. This proof is done in the infinite-momentum frame in which the momenta of $\pi$,…

High Energy Physics - Phenomenology · Physics 2013-02-27 Zhen-Hua Zhang , Xin-Heng Guo , Gang Lü

We present upgraded theoretical predictions for inclusive and exclusive radiative decays of {\it B} mesons. Our results include those next-to-leading order corrections that have already been computed. Our best estimates in the Standard…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Ciuchini , E. Franco , G. Martinelli , L. Reina , L. Silvestrini

We present in detail the calculation of the virtual O(alpha_s) corrections to the inclusive semi-leptonic rare decay b --> s l+ l-. We also include those O(alpha_s) bremsstrahlung contributions which cancel the infrared and mass…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. H. Asatryan , H. M. Asatrian , C. Greub , M. Walker