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Related papers: Towards a fully massive five-flavour scheme

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We check the impact of the factorization scheme employed in the calculation of the heavy-quark deep-inelastic scattering (DIS) electro-production on the PDFs determined in the NNLO QCD analysis of the world inclusive neutral-current DIS…

High Energy Physics - Phenomenology · Physics 2009-08-24 S. Alekhin , J. Blümlein , S. Klein , S. Moch

We consider a detailed account on the construction of the heavy-quark parton distribution functions for charm and bottom, starting from $n_f=3$ light flavors in the fixed-flavor number (FFN) scheme and by using the standard decoupling…

High Energy Physics - Phenomenology · Physics 2020-09-23 S. Alekhin , J. Bluemlein , S. Moch

The Thorne-Roberts variable flavour number scheme (VFNS) for heavy quarks is presented in detail for the specific case of charged current DIS. As in neutral current DIS this provides a smooth extrapolation from the fixed flavour number…

High Energy Physics - Phenomenology · Physics 2009-01-07 R. S. Thorne , R. G. Roberts

We propose a model based on the $SU(5)$ grand unification with an extra $Z_{2}\otimes Z_{2}^{\prime}\otimes Z_{2}^{\prime \prime}\otimes Z_{4}\otimes Z_{12}$ flavor symmetry, which successfully describes the observed SM fermion mass and…

High Energy Physics - Phenomenology · Physics 2014-11-13 A. E. Cárcamo Hernández , Sergey Kovalenko , Iván Schmidt

Present situation in the flavour mixing of quarks and leptons is briefly reviewed and a new approach called the Minimal Flavour Mixing (MFM) is considered in detail. According to MFM the whole of the flavour mixing is basically determined…

High Energy Physics - Phenomenology · Physics 2017-08-23 J. L. Chkareuli

I present a method for calculating heavy quark production which extrapolates smoothly from the well understood limits of the fixed-flavour number scheme for Q^2 approx m_H^2 to the zero-mass scheme at Q^2/m_H^2 -> infinity. For all Q^2 >…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. S. Thorne

The hadroproduction of heavy-flavoured mesons has recently attracted a growing interest e.g. within the people involved in global analysis of proton and nuclear parton distribution functions, saturation physics, and physics of cosmic rays.…

High Energy Physics - Phenomenology · Physics 2018-12-03 Ilkka Helenius , Hannu Paukkunen

We discuss a new general class of mass matrix ansatz that respects the fermion mass hierarchy and calculability of the flavor mixing matrix. This is a generalization and justification of the various specific forms of the mass matrix by…

High Energy Physics - Phenomenology · Physics 2014-11-17 Kyungsik Kang , Sin Kyu Kang

There are presently two approaches to calculating heavy quark production for the deeply inelastic scattering process in current literature. The conventional fixed-flavor scheme focuses on the flavor creation mechanism and includes the heavy…

High Energy Physics - Phenomenology · Physics 2007-05-23 Pankaj Agrawal , Fredrick I. Olness , Stephan T. Riemersma , Wu-Ki Tung

Several key processes at the LHC in the standard model and beyond that involve $b$ quarks, such as single-top, Higgs, and weak vector boson associated production, can be described in QCD either in a 4-flavor or 5-flavor scheme. In the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Fabio Maltoni , Giovanni Ridolfi , Maria Ubiali

We discuss a new general class of mass matrix ansatz that respects the fermion mass hierarchy and calculability of the flavor mixing matrix. This is a generalization of the various specific forms of the mass matrix that is obtained by…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kyungsik Kang , Sin Kyu Kang

Where appropriate, the abbreviation 'VFNS' is replaced by 'CSN' to indicate the scheme using massive heavy quark coefficient functions proposed in this paper. The text below Eq. (2.13) and between Eqs. (2.33) and (2.36) has been…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Chuvakin , J. Smith , W. L. van Neerven

We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass…

High Energy Physics - Phenomenology · Physics 2014-11-17 Harald Fritzsch , Zhi-zhong Xing

We present an analysis on flavour anomalies in semileptonic rare $B$-meson decays using an effective field theory approach and assuming that new physics affects only one generation in the interaction basis and non-universal mixing effects…

High Energy Physics - Phenomenology · Physics 2026-03-09 Jorge Alda , Alejandro Mir , Siannah Penaranda

We critically review heavy quark mass effects in DIS and their impact on global analyses. We lay out all elements of a properly defined general mass variable flavor number scheme (GM VFNS) that are shared by all modern formulations of the…

High Energy Physics - Phenomenology · Physics 2009-01-21 R. S. Thorne , W. K. Tung

We show that the well-known obstacle for working with the zero-mass variable flavor number scheme, namely, the omission of O(1) mass power corrections close to the conventional heavy flavor matching point (HFMP) mu_b=m, can be easily…

High Energy Physics - Phenomenology · Physics 2018-05-09 Valerio Bertone , Alexandre Glazov , Alexander Mitov , Andrew Papanastasiou , Maria Ubiali

We argue that flavour mixing, both in the quark and lepton sector, follows the minimal mixing pattern, according to which the whole of this mixing is basically determined by the physical mass generation for the first family of fermions. So,…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. L. Chkareuli , C. D. Froggatt , H. B. Nielsen

Tempering is used to change the quark mass while remaining in equilibrium between the trajectories of a standard hybrid Monte Carlo simulation of four flavours of staggered fermions. The algorithm is faster for small enough quark masses,…

High Energy Physics - Lattice · Physics 2007-05-23 G. Boyd

We study the sensitivity of our recent MSTW 2008 NLO and NNLO PDF analyses to the values of the charm- and bottom-quark masses, and we provide additional public PDF sets for a wide range of these heavy-quark masses. We quantify the impact…

High Energy Physics - Phenomenology · Physics 2010-11-23 A. D. Martin , W. J. Stirling , R. S. Thorne , G. Watt

We analyse the sensitivity of quark flavour-changing observables to the MSSM, in a regime of heavy superpartner masses. We analyse four distinct and motivated frameworks characterising the structure of the soft-breaking terms by means of…

High Energy Physics - Phenomenology · Physics 2020-04-22 Gino Isidori , Sokratis Trifinopoulos