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

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In this paper, we present analytical results for the two-loop QCD corrections to the production of two partons or a photon and a parton in hadronic collisions, mediated by loops of massive quarks. These amplitudes involve Feynman integrals…

High Energy Physics - Phenomenology · Physics 2025-09-22 Federico Coro , Christoph Nega , Lorenzo Tancredi , Fabian J. Wagner

We calculate the pressure for pure-glue QCD at high temperature to two-loop order using hard-thermal-loop (HTL) perturbation theory. At this order, all the ultraviolet divergences can be absorbed into renormalizations of the vacuum energy…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jens O. Andersen , Eric Braaten , Emmanuel Petitgirard , Michael Strickland

Within an effective field theory framework we study heavy-quark--antiquark systems with a typical distance between the heavy quark and the antiquark smaller than $1/\Lambda_{\rm QCD}$. A suitable definition of the potential is given within…

High Energy Physics - Phenomenology · Physics 2015-06-25 N. Brambilla , A. Pineda , J. Soto , A. Vairo

We give an analytic formula for the double distribution of hadronic invariant mass and charged lepton energy to one-loop order of the perturbative QCD. Although infrared singular, this quantity is closely related to physical observables…

High Energy Physics - Phenomenology · Physics 2011-04-15 M. Jezabek , P. Urban

Recent calculations of heavy quark cross sections near threshold at next-to-next-to-leading order have found second-order corrections as large as first-order ones. We analyse long-distance contributions to the heavy quark potential in…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Beneke

We study several issues related to the use of effective field theories in QCD at large baryon density. We show that the power counting is complicated by the appearance of two scales inside loop integrals. Hard dense loops involve the large…

High Energy Physics - Phenomenology · Physics 2010-04-05 Thomas Schaefer

The QCD-coupling is a necessary input in the computation of many observables, and the parametric error on input parameters can be a dominant source of uncertainty. The coupling can be extracted by comparing high order perturbative…

High Energy Physics - Lattice · Physics 2022-03-16 Leonardo Chimirri , Rainer Sommer

An equivariant BRST-construction is used to define the continuum SU(3) gauge theory on a finite torus. I corroborate previous results using renormalization group techniques by explicitly computing the measure on the moduli-space of the…

High Energy Physics - Theory · Physics 2009-10-31 Martin Schaden

We present the one-loop QCD amplitudes for two external massless quarks and three external gluons ($\bar{q}qggg$). This completes the set of one-loop amplitudes needed for the next-to-leading-order corrections to three-jet production at…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. A. Kosower

We study effective energies of heavy-light meson correlation functions in lattice QCD and a small volume of (0.2 fm)^4 to non-perturbatively calculate their dependence on the heavy quark mass in the continuum limit. Our quenched results…

High Energy Physics - Lattice · Physics 2009-11-10 Jochen Heitger , Jan Wennekers

A quark confinement potential is derived from QCD Lagrangial under the two assumptions in the energy region relevant to quark confinement. The possibility of perturbation in QCD is assumed, and the momentum of the gluon transfered by the…

Nuclear Theory · Physics 2007-05-23 Yongkyu Ko

We compute, to two loops in pertubation theory, the fermionic contribution to rectangular RxT Wilson loops, for different values of R and T. We use the overlap fermionic action. We also employ the clover action, for comparison with existing…

High Energy Physics - Lattice · Physics 2016-09-01 A. Athenodorou , H. Panagopoulos

We calculate the one-loop effective potential at finite temperature for a system of massless scalar fields with quartic interaction $\lambda\phi^4$ in the framework of the boundary effective theory (BET) formalism. The calculation relies on…

High Energy Physics - Phenomenology · Physics 2011-06-30 A. Bessa , C. A. A. de Carvalho , E. S. Fraga , F. Gelis

We consider the factorization properties of on-shell QCD amplitudes with massive partons in the limit when all kinematical invariants are large compared to the parton mass and discuss the structure of their infrared singularities. The…

High Energy Physics - Phenomenology · Physics 2009-01-07 S. Moch , A. Mitov

We complete the derivation of the Cornwall-Jackiw-Tomboulis effective potential for quark propagator at finite temperature and finite quark chemical potential in the real-time formalism of thermal field theory and in Landau gauge. In the…

High Energy Physics - Theory · Physics 2014-11-18 Zhou Bang-Rong

We analyze the dependence of heavy quark free energies on the baryon chemical potential (mu_b) in 2-flavour QCD using improved (p4) staggered fermions with a bare quark mass of m/T = 0.4. By performing a 6th order Taylor expansion in the…

High Energy Physics - Lattice · Physics 2009-01-07 M. Doring , S. Ejiri , O. Kaczmarek , F. Karsch , E. Laermann

We compute the two-loop contribution to the QCD pressure in a strong magnetic background, for arbitrary quark masses. We show that, for very large fields, the chiral limit is trivial.

High Energy Physics - Phenomenology · Physics 2013-05-01 Jean-Paul Blaizot , Eduardo S. Fraga , Leticia F. Palhares

We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors $F_1$ and $F_2$ involving a closed loop of massless fermions. This subset is gauge invariant and contains both planar and non-planar…

High Energy Physics - Phenomenology · Physics 2018-04-18 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

The strange quark mass is determined from a new QCD Finite Energy Sum Rule (FESR) optimized to reduce considerably the systematic uncertainties arising from the hadronic resonance sector. As a result, the main uncertainty in this…

High Energy Physics - Phenomenology · Physics 2009-01-06 Cesareo A. Dominguez , Nasrallah F. Nasrallah , Raoul Röntsch , Karl Schilcher

If the fermion mass is large enough, the phase of the fermion determinant of QCD at finite density is strongly correlated with the imaginary part of the Polyakov loop. This fact can be exploited to reduce the fluctuations of the phase…

High Energy Physics - Lattice · Physics 2015-06-25 Philippe de Forcrand , Victor Laliena