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Related papers: Two-loop perturbative corrections to the constrain…

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We use the recently obtained two-loop hard thermal loop perturbation theory thermodynamics functions of a plasma of quarks and gluons to compute the diagonal second- and fourth-order quark number susceptibilities. The two-loop hard thermal…

High Energy Physics - Phenomenology · Physics 2013-08-07 Najmul Haque , Munshi G. Mustafa , Michael Strickland

We present a determination of a new class of Feynman diagrams relevant for second-order QCD corrections to the top quark decay t -> b W. Modern computing techniques allow us to perform a reduction of the original loop integrals to master…

High Energy Physics - Phenomenology · Physics 2017-08-23 Maciej Slusarczyk

As it was suggested by previous works on a modified perturbation expansion for QCD, the possibility for the generation of large quark condensates in the mass-less version of the theory is explored. For this purpose, it is firstly presented…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alejandro Cabo Montes de Oca , Danny Martinez-Pedrera

We evaluate the fermionic two-loop QCD corrections to the heavy-quark pair production process in the quark-antiquark channel. We obtain analytic results which are valid for any value of the Mandelstam invariants s and t, and of the heavy…

High Energy Physics - Phenomenology · Physics 2009-11-13 R. Bonciani , A. Ferroglia , T. Gehrmann , D. Maitre , C. Studerus

This talks contains a short introduction to Chiral Perturbation Theory and the existing calculations to two-loop order in the mesonic sector. I include a discussion on which quantities the expansion can be organized in. The present best…

High Energy Physics - Lattice · Physics 2008-11-26 Johan Bijnens

In quantum chromodynamics (QCD), the binding energy of an infinitely heavy quark--antiquark pair in a color singlet state can be calculated as a function of the distance. We investigate this static potential of QCD perturbatively and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Y. Schroder

We compute the three-loop corrections to the potential of two heavy quarks. In particular we consider in this Letter the purely gluonic contribution which provides in combination with the fermion corrections of Ref. \cite{Smirnov:2008pn}…

High Energy Physics - Phenomenology · Physics 2010-04-23 Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We apply the Local Composite Operator method to construct the three loop effective potential for the dimension two operator $\frac{1}{2} { A_\mu^a }^2$ in the Landau gauge in Quantum Chromodynamics. For $SU(3)$ we show that the three loop…

High Energy Physics - Theory · Physics 2022-09-21 J. A. Gracey

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

In the present paper, we return to the problem on a spontaneous generation of the $A_0$-background field in QCD at finite temperature and include in addition a quark chemical potential, $\mu$. We reproduce the known expressions in terms of…

High Energy Physics - Theory · Physics 2021-12-01 M. Bordag , V. Skalozub

We calculate all those QCD $N$-point functions which are relevant for a three-loop QCD thermodynamics calculation with finite quark masses within the hard the thermal loop approximation. Using the effective quark propagator, we also…

High Energy Physics - Phenomenology · Physics 2018-07-16 Najmul Haque

We obtain the two-loop effective potential for general renormalizable theories, using a generalized gauge-fixing scheme that includes as special cases the background-field $R_\xi$ gauges, the Fermi gauges, and the familiar Landau gauge, and…

High Energy Physics - Phenomenology · Physics 2018-10-24 Stephen P. Martin , Hiren H. Patel

We compute the pressure of hot quantum electrodynamics from the two-loop truncation of the 2PI effective action. Since the 2PI resummation guarantees gauge-fixing independence only up to the order of the truncation, our result for the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Szabolcs Borsanyi , Urko Reinosa

We present results of a simulation of QCD on a 4x16^3 lattice with 2 continuum flavors of p4-improved staggered fermion with mass m/T=0.4. Derivatives of the thermodynamic grand potential with respect to quark chemical potential mu_q up to…

High Energy Physics - Lattice · Physics 2011-05-05 C. R. Allton , S. Ejiri , S. J. Hands , O. Kaczmarek , F. Karsch , E. Laermann , C. Schmidt

We calculate the quark contribution to the free energy of a hot quark-gluon plasma to two-loop order using hard-thermal-loop (HTL) perturbation theory. All ultraviolet divergences can be absorbed into renormalizations of the vacuum energy…

High Energy Physics - Phenomenology · Physics 2009-11-10 Jens O. Andersen , Emmanuel Petitgirard , Michael Strickland

It is well known that effective potentials can be gauge-dependent while their values at extrema should be gauge-invariant. Unfortunately, establishing this invariance in perturbation theory is not straightforward, since contributions from…

High Energy Physics - Phenomenology · Physics 2015-06-22 Anders Andreassen , William Frost , Matthew D. Schwartz

Expressions for the potentials appearing in the nonrelativistic effective field theory description of doubly heavy baryons are known in terms of operator insertions in the Wilson loop. However, their evaluation requires nonperturbative…

High Energy Physics - Phenomenology · Physics 2021-11-19 Joan Soto , Jaume Tarrús Castellà

We briefly review how nonrelativistic effective field theories give us a definition of the QCD potentials and a coherent field theory derived quantum mechanical scheme to calculate the properties of bound states made by two or more heavy…

High Energy Physics - Phenomenology · Physics 2009-01-08 Nora Brambilla

We study the radiative corrections to the Chern-Simons mass term at two loops in 2+1 dimensional quantum electrodynamics at finite temperature. We show that, in contrast to the behavior at zero temperature, thermal effects lead to a non…

High Energy Physics - Theory · Physics 2009-10-31 F. T. Brandt , Ashok Das , J. Frenkel , K. Rao

We calculate the two-loop effective action of QED for arbitrary constant electromagnetic fields at finite temperature T in the limit of T much smaller than the electron mass. It is shown that in this regime the two-loop contribution always…

High Energy Physics - Phenomenology · Physics 2009-09-25 Holger Gies