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Related papers: Simultaneous decoupling of bottom and charm quarks

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We review the model-independent description of the couplings of the top quark to the Higgs and gauge bosons in theories beyond the Standard Model. Then we examine these couplings in the case of arbitrary heavy vector-like quarks mixing with…

High Energy Physics - Phenomenology · Physics 2015-06-15 J. A. Aguilar-Saavedra , M. Perez-Victoria

The $b\bar b$ spectrum is calculated with the use of a relativistic Hamiltonian where the gluon-exchange between a quark and an antiquark is taken as in background perturbation theory. We observed that the splittings $\Delta_1=…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. M. Badalian , A. I. Veselov , B. L. G. Bakker

New data for the total cross section $\sigma(e^+e^-\to{hadrons})$ in the charm and bottom threshold region are combined with an improved theoretical analysis, which includes recent four-loop calculations, to determine the short distance…

High Energy Physics - Phenomenology · Physics 2008-11-26 Johann H. Kuehn , Matthias Steinhauser , Christian Sturm

The heavy charm and bottom quarks are unique probes of the transport properties of the quark-gluon plasma (QGP) and its hadronization in high-energy nuclear collisions. A key challenge in this context is to embed the interactions of the…

Nuclear Theory · Physics 2025-12-30 Tharun Krishna , Ralf Rapp , Yu Fu , Steffen A. Bass , Weiyao Ke

We revisit the calculation of nonfactorizable corrections induced by charm-quark loops in exclusive FCNC $B$-decays. For the sake of clarity, we make use of a field theory with scalar particles: this allows us to focus on the conceptual…

High Energy Physics - Phenomenology · Physics 2018-10-31 Anastasiia Kozachuk , Dmitri Melikhov

We study the dependence on the charm quark mass of the leading-order low-energy constants of the $\Delta S=1$ effective Hamiltonian, with the aim of elucidating the role of the charm mass scale in the $\Delta I=1/2$ rule for $K\to\pi\pi$…

High Energy Physics - Lattice · Physics 2016-07-08 Eric Endress , Carlos Pena

We report on our ongoing determination of the charm quark mass and the masses and decay constants of various charmed mesons, obtained within a mixed-action setup. We employ $N_f=2+1$ CLS ensembles combined with a Wilson twisted mass valence…

High Energy Physics - Lattice · Physics 2021-12-02 A. Bussone , A. Conigli , J. Frison , G. Herdoíza , C. Pena , D. Preti , J. Á. Romero , J. Ugarrio

We review the present status and the future prospects for the measurements of the Higgs Yukawa couplings to light quarks and charm. A special focus is given to novel proposed off-shell probes, which offer promising and complementary…

High Energy Physics - Phenomenology · Physics 2022-06-09 Natascia Vignaroli

With the increasing experimental precision available at colliders, higher-order perturbative calculations are required to reduce the theory uncertainty in order to extract crucial QCD parameters, such as the strong coupling constant, to the…

High Energy Physics - Phenomenology · Physics 2022-08-15 Marco Saragnese

We study the complete non-decoupling effects of the standard model Higgs boson to one loop. Using effective field theory methods, we integrate out the Higgs boson and represent its non-decoupling effects by a set of gauge invariant…

High Energy Physics - Phenomenology · Physics 2009-10-28 Maria J. Herrero , Ester Ruiz Morales

The charged axial-vector $J^{P}=1^{+}$ tetraquarks $Z_{q}=[cq][\bar {b} \bar q ]$ and $Z_{s}=[cs][\bar {b} \bar s]$ with the open charm-bottom contents are studied in the diquark-antidiquark model. The masses and meson-current couplings of…

High Energy Physics - Phenomenology · Physics 2017-06-28 S. S. Agaev , K. Azizi , H. Sundu

The $DD^*$ scattering phase shifts in the $T_{cc}^+=cc\bar{u}\bar{d}$ channel are extracted from lattice QCD for five different charm quark masses and a fixed light-quark mass corresponding to $m_\pi\simeq 280$~MeV. The phase shifts are…

High Energy Physics - Lattice · Physics 2024-11-21 Sara Collins , Alexey Nefediev , M. Padmanath , Sasa Prelovsek

By means of QCD simulations on the lattice, we compute the coupling of the heavy-light mesons to a soft pion in the static heavy quark limit. The gauge field configurations used in this calculations include the effect of N_f=2 dynamical…

High Energy Physics - Phenomenology · Physics 2010-05-28 Damir Becirevic , Benoit Blossier , Emmanuel Chang , Benjamin Haas

We present preliminary results from a lattice calculation of tetraquark states in the charm and bottom sector of the type $ud\bar{b}\bar{b}$, $us\bar{b}\bar{b}$, $ud\bar{c}\bar{c}$ and $sc\bar{b}\bar{b}$. These calculations are performed on…

High Energy Physics - Lattice · Physics 2018-05-01 Parikshit Junnarkar , M Padmanath , Nilmani Mathur

We compute three-loop corrections to the Higgs-gluon form factor, incorporating the top quark mass dependence. Our method is based on the combination of expansions around the top threshold and for large top quark mass, using conformal…

High Energy Physics - Phenomenology · Physics 2020-09-18 Joshua Davies , Ramona Groeber , Andreas Maier , Thomas Rauh , Matthias Steinhauser

We perform an integral reduction for the 3-loop effective gauge coupling and screening mass of QCD at high temperatures, defined as matching coefficients appearing in the dimensionally reduced effective field theory (EQCD). Expressing both…

High Energy Physics - Phenomenology · Physics 2015-06-05 Jan Moeller , York Schroder

We review the experimental measurements and theoretical descriptions of leptonic and semileptonic decays of particles containing a single heavy quark, either charm or bottom. Measurements of bottom semileptonic decays are used to determine…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jeffrey D. Richman , Patricia R. Burchat

I calculate the QED coupling, alpha, directly in the MS-bar scheme using an unsubtracted dispersion relation for the three light quarks, and perturbative QCD for charm and bottom quarks. Compact analytical expressions are presented, making…

High Energy Physics - Phenomenology · Physics 2010-04-06 Jens Erler

The coupling of a pseudo-scalar Higgs boson to gluons is mediated through a heavy quark loop. In the limit of large quark mass, it is described by an effective Lagrangian that only admits light degrees of freedom. In this effective theory,…

High Energy Physics - Phenomenology · Physics 2016-01-20 Taushif Ahmed , Thomas Gehrmann , Prakash Mathews , Narayan Rana , V. Ravindran

We present the method and compute the strong couplings of the lowest and first orbitally excited heavy-light mesons to a soft pion in the static heavy quark limit on the lattice. Besides the usual g^ and \~g couplings, we were able to make…

High Energy Physics - Lattice · Physics 2012-03-02 Damir Becirevic , Emmanuel Chang , Alain Le Yaouanc