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Related papers: On the Theoretical Understanding of Inclusive $\La…

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We apply perturbative QCD factorization theorems to inclusive heavy hadron decays, and obtain simultaneously a low semileptonic branching ratio $B(B\to Xl\bar{\nu})=10.16%$, the average charm yield $<n_c>=1.17$ per $B$ decay, a small…

High Energy Physics - Phenomenology · Physics 2009-10-31 We-Fu Chang , Hsiang-nan Li , Hoi-Lai Yu

We provide upper and lower bounds on the semileptonic weak decay form factors for $B \to D^(*)$ and $\Lambda_b \to \Lambda_c$ decays by utilizing inclusive heavy quark effective theory sum rules. These bounds are calculated to second order…

High Energy Physics - Phenomenology · Physics 2009-10-31 Cheng-Wei Chiang

We present an analytic formula for the $O(\alpha_s)$ corrections to the decay $t\to H^+b$ for nonzero $m_H$ and $m_b$. The Equivalence Theorem is used to relate these corrections to those for the process $t\to W^+b$. Contrary to previously…

High Energy Physics - Phenomenology · Physics 2009-10-22 Andrzej Czarnecki , Sacha Davidson

Exploiting recently proposed novel improvements of the techniques used for extracting from QCD sum rules pivotal hadron characteristics, including their systematic errors, we succeed to achieve a conspicuous agreement of the predictions of…

High Energy Physics - Phenomenology · Physics 2014-04-15 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

Based on the nonrelativistic QCD factorization theorem, we resum QCD corrections to the inclusive decay rate of $\eta_c$ and $\eta_b$ in the large-$n_f$ limit using bubble chain resummation. By employing dimensional regularization, we show…

High Energy Physics - Phenomenology · Physics 2018-12-24 Nora Brambilla , Hee Sok Chung , Javad Komijani

Starting from the most general effective $|\Delta B| = 1$ Hamiltonian describing non-leptonic $b$-quark decays $b\to q_1 \bar q_2 q_3$, we compute analytic expressions for all matching coefficients of the two-quark operator contributions in…

High Energy Physics - Phenomenology · Physics 2026-05-27 Martin Lang , Alexander Lenz , Ali Mohamed , Maria Laura Piscopo , Aleksey V. Rusov

We calculate the electron spectrum of semileptonic decays of B-mesons into non-charmed hadrons. The shape of the spectrum obtained from QCD sum rules is in general agreement with quark model calculations. At high electron energies the…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Ball , V. M. Braun , H. G. Dosch

Precision tests of the CKM mechanism and searches for new physics in the flavour sector require dedicated QCD calculations of decay widths and spectra. Significant progress has been achieved in recent years in computing inclusive B decay…

High Energy Physics - Phenomenology · Physics 2008-06-30 Einan Gardi

I illustrate the role of infrared renormalons in computing inclusive B-decay spectra. I explain the relation between the leading ambiguity in the definition of Sudakov form factor \sim \exp(N\Lambda/M) and that of the pole mass, and show…

High Energy Physics - Phenomenology · Physics 2017-08-23 Einan Gardi

The rare inclusive decay $\bar{B}\rightarrow X_s\gamma$ is an important probe of physics beyond the standard model. The largest uncertainty on the decay rate and CP asymmetry comes from operators that appear at order $1/m_b$ in the heavy…

High Energy Physics - Phenomenology · Physics 2019-09-20 Ayesh Gunawardana

We derive the imaginary part of the potential NRQCD Hamiltonian up to order 1/m^4, when the typical momentum transfer between the heavy quarks is of the order of Lambda_{QCD} or greater, and the binding energy E much smaller than…

High Energy Physics - Phenomenology · Physics 2009-11-07 Nora Brambilla , Dolors Eiras , Antonio Pineda , Joan Soto , Antonio Vairo

We give an updated summary of the topics covered in Working Group I of the 2nd Workshop on the CKM Unitarity Triangle, with emphasis on the results obtained since the 1st CKM Workshop. The topics covered include the measurement of |V_{ub}|,…

High Energy Physics - Phenomenology · Physics 2010-11-23 Laurent Lellouch

A possibility is considered of explaining the low experimental value of the ratio of the lifetimes tau(Lambda_b)/tau(B_d) by a new `centiweak' four-quark interaction, i.e with a strength on the order of 10^{-2}G_F. It is noted that the…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. B. Voloshin

We demonstrate that Borel QCD sum rules for heavy-light currents entail a very strong correlation between the $b$-quark mass $m_b$ and the $B$-meson decay constant $f_B,$ that is, $\delta f_B/f_B\approx-8\delta m_b/m_b.$ By starting from…

High Energy Physics - Phenomenology · Physics 2014-04-15 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

We overview the current status and future perspectives of the QCD-based method of light-cone sum rules. The two main versions of these sum rules, using light-meson and $B$-meson distribution amplitudes are introduced and the most important…

High Energy Physics - Phenomenology · Physics 2023-11-16 Alexander Khodjamirian , Blaženka Melić , Yu-Ming Wang

We discuss the problem of the large discrepancy between the observed lifetime ratio of $\Lambda_b$ to $B_d$ and the theoretical prediction obtained by the heavy quark effective theory. A new possibility of solving this problem is proposed…

High Energy Physics - Phenomenology · Physics 2009-10-30 Toshiaki Ito , Masahisa Matsuda , Yoshimitsu Matsui

We study the inclusive decay widths of singly heavy baryons with the improved bag model in which the unwanted center-of-mass motion is removed. Additional insight is gained by comparing the charmed and bottom baryons. We discuss the running…

High Energy Physics - Phenomenology · Physics 2023-08-02 Hai-Yang Cheng , Chia-Wei Liu

Theoretical predictions for B decay rates are rewritten in terms of the Upsilon meson mass instead of the b quark mass, using a modified perturbation expansion. The theoretical consistency is shown both at low and high orders. This method…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zoltan Ligeti

We compute the Darwin operator contribution ($1/m_b^3$ correction) to the width of the inclusive non-leptonic decay of a $B$ meson ($B^+$, $B_d$ or $B_s$), stemming from the quark flavour-changing transition $b \to q_1 \bar q_2 q_3$, where…

High Energy Physics - Phenomenology · Physics 2021-01-25 Alexander Lenz , Maria Laura Piscopo , Aleksey V. Rusov

Recent progress in calculating O(alpha_s^2) corrections to inclusive and exclusive semileptonic b-->c transitions is reviewed. The impact of these corrections on the |V_cb| determination from both inclusive and exclusive B decays is…

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