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Related papers: Heavy-to-heavy quark decays at NNLO

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Neutral flavor-changing transitions are hugely suppressed in the Standard Model and therefore they are very sensitive to new physics. We consider the decay rate of t->u_i h where u_i=u,c using an effective field theory approach. We perform…

High Energy Physics - Phenomenology · Physics 2013-09-11 Cen Zhang , Fabio Maltoni

I give an introduction to the QCD-based theory of the heavy flavor hadrons and their weak decays. Trying to remain at the next-to-elementary level and skip technicalities, I concentrate on the qualitative description of the most important…

High Energy Physics - Phenomenology · Physics 2007-05-23 Nikolai Uraltsev

We consider the full genuine next-to-leading order SUSY-QCD corrections to the charged Higgs decays into quarks supplemented by the NNLO corrections to the effective top and bottom Yukawa couplings. The NNLO corrections to the effective top…

High Energy Physics - Phenomenology · Physics 2023-06-21 Jamie Chang , Fiona Kirk , Margarete Mühlleitner , Michael Spira

The Heavy Quark Expansion (HQE) has become an extremely powerful tool in flavor physics. For charm decays, where the expansion parameters $\alpha_s(m_c)$ and $\Lambda_{\rm QCD}/m_c$ are bigger than for bottom decays, it remains to be seen…

High Energy Physics - Phenomenology · Physics 2020-01-29 Matteo Fael , Thomas Mannel , K. Keri Vos

We extend our relativistic quark model to the study of the decay Lambda_b -> Lambda_c ell nu and verify that the model satisfies the heavy-quark symmetry constraints at order 1/mQ^2. We isolate a strong dependence on a parameter which…

High Energy Physics - Phenomenology · Physics 2010-11-01 B. Holdom , M. Sutherland , J. Mureika

In the heavy quark effective field theory of QCD, we analyze the order 1/m_Q contributions to heavy to light vector decays. Light cone sum rule method is applied with including the effects of 1/m_Q order corrections. We then extract…

High Energy Physics - Phenomenology · Physics 2009-11-11 W. Y. Wang , Y. L. Wu , M. Zhong

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 review the main aspects of the fragmentation of bottom quarks in top quark decay. The NLO b-quark energy spectrum presents large mass logarithms ln(m_t^2/m_b^2), which can be resummed by the use of the approach of perturbative…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gennaro Corcella

We present a detailed analysis of the heavy-to-light semileptonic decays of the Lambda_b and Lambda_c baryons Lambda_b -> p l- bar(nu)_l and Lambda_c -> n l+ nu_l in the covariant confined quark model. We calculate the invariant and…

High Energy Physics - Phenomenology · Physics 2015-01-07 Thomas Gutsche , Mikhail A. Ivanov , Jurgen G. Korner , Valery E. Lyubovitskij , Pietro Santorelli

The status of heavy-quark decays as of summer 1999 is reviewed. New measurements of semileptonic B decays from LEP and from CLEO are reported and the status of determining the CKM parameters |Vcb| and |Vub| is assessed. Rare charmless…

High Energy Physics - Experiment · Physics 2010-11-23 Ronald A. Poling

We evaluate analytically the master integrals for double real radiation emission in the b --> u W* decay, where b and u are a massive and massless quark, respectively, while W* is an off-shell charged weak boson. Since the W boson can…

High Energy Physics - Phenomenology · Physics 2018-09-26 Roberto Bonciani , Alessandro Broggio , Leandro Cieri , Andrea Ferroglia

We present $O(\alpha_s^2)$ QCD corrections to the fully-differential decay rate of a $b$-quark into inclusive semileptonic charmless final states. Our calculation provides genuine two-loop QCD corrections, beyond the…

High Energy Physics - Phenomenology · Physics 2015-06-12 Mathias Brucherseifer , Fabrizio Caola , Kirill Melnikov

We compute the virtual O(alpha_s^2) fermionic contributions to the charm quark mass dependent matrix elements of the B -> X_s gamma decay. In the case of a massless quark loop insertion into the gluon propagator, our result obtained as an…

High Energy Physics - Phenomenology · Physics 2009-02-18 R. Boughezal , M. Czakon , T. Schutzmeier

The paper is devoted to the calculation of the two-loop O(alpha_s y^2) and O(y^4) MSSM corrections to the relation between the pole mass of the b-quark and its running mass in DR scheme. To evaluate the needed diagrams the large mass…

High Energy Physics - Phenomenology · Physics 2011-01-27 A. Bednyakov , A. Sheplyakov

We present an analytical calculation of the $\alpha_s$ corrections for the coefficient of $\rho_D/m_Q^3$ term in the heavy quark expansion for the inclusive semileptonic decays of heavy hadrons, such as $B \to X_c \ell \bar{\nu}$. The full…

High Energy Physics - Phenomenology · Physics 2019-11-20 Thomas Mannel , Alexei A. Pivovarov

We calculate the large top quark mass expansions for the H -> bb_bar decay rate in the order (alpha_s)^2 and for the H -> gluons decay rate in the order (alpha_s)^3. The obtained expansions rapidly converge in the region of their validity,…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. A. Larin , T. van Ritbergen , J. A. M. Vermaseren

We present analytical results for master integrals emerging in the computation of differential rates for inclusive weak decays of heavy flavors at next-to-leading order (NLO) in QCD. As an immediate physical application, these master…

High Energy Physics - Phenomenology · Physics 2022-01-05 Th. Mannel , D. Moreno , A. A. Pivovarov

Bauer, Ligeti and Luke have recently proposed a new method for measuring |V_{ub}| in inclusive semileptonic B decays, using a cut on the lepton invariant mass to discriminate against b->c transitions. We investigate the structure of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Matthias Neubert

We present a number of exact relations for the heavy quark limit and develop an analytical 1/m_Q expansion for heavy mesons in the 't Hooft model. Among the new results are relation 3\mu_\pi^2=\bar\Lambda^2 - m_{sp}^2+\beta^2, 1/m_Q…

High Energy Physics - Phenomenology · Physics 2009-10-31 Matthias Burkardt , Nikolai Uraltsev

We review recent advances in the theory of strong-interaction effects and final-state interactions in hadronic weak decays of heavy mesons. In the heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can be calculated…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert
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