Tue·Sep 28, 2004Tuesday·September 28, 2004

1. 01*

   MEM study of true flattening of free energy and the $\theta$ term

   Masahiro Imachi🇯🇵 · Yasuhiko Shinno🇯🇵 · Hiroshi Yoneyama🇯🇵

   We study the sign problem in lattice field theory with a $\theta$ term, which reveals as flattening phenomenon of the free energy density $f(\theta )$. We report the result of the MEM analysis, where such mock data are used that `true' flattening of $f(\theta )$ occurs. This is regarded as a simple model for studying whether the MEM could correctly detect non trivial phase structure in $\theta$ space. We discuss how the MEM distinguishes fictitious and true flattening.

   hep-latNucl.Phys.B Proc.Suppl.(2005)·0 citations
2. 02*

   Charmonia at finite momenta in a deconfined plasma

   Saumen Datta🇩🇪 · Frithjof Karsch🇩🇪 · Peter Petreczky🇺🇸 · Soenke Wissel🇩🇪 · Ines Wetzorke🇩🇪

   Lattice studies of charmonium systems have indicated that in a deconfined gluonic plasma ground state charmonia survive as bound states upto temperatures \~ 2 Tc. After surveying the methodologies used in reaching these results, we examine the behavior of these systems when the bound state is in motion with respect to the heatbath frame. We find that the finite momenta charmonia show medium modifications when the medium is deconfined; in particular, a modification of the energy-momentum dispersion relation is indicated.

   hep-lat34 citations
3. 03*

   Measuring interface tensions in 4d SU(N) lattice gauge theories

   Biagio Lucini🇨🇭 · Philippe de Forcrand🇨🇭 · Michele Vettorazzo🇨🇭

   We propose a new algorithm to compute the order-order interface tension in SU(N) lattice gauge theories. The algorithm is trivially generalizable to a variety of models, e.g., spin models. In the case N=3, via the perfect wetting hypothesis, we can estimate the order-disorder interface tension. In the case N=4, we study the ratio of dual k-tensions and find that it satisfies Casimir scaling down to T=1.2 T_c.

   hep-latNucl.Phys.B Proc.Suppl.(2005)·41 citations
4. 04*

   Two and three loops computations of renormalization constants for lattice QCD

   F. Di Renzo🇮🇹 · A. Mantovi🇮🇹 · V. Miccio🇮🇹 · L. Scorzato🇩🇪 · C. Torrero🇮🇹

   Renormalization constants can be computed by means of Numerical Stochastic Perturbation Theory to two/three loops in lattice perturbation theory, both in the quenched approximation and in the full (unquenched) theory. As a case of study we report on the computation of renormalization constants of the propagator for Wilson fermions. We present our unquenched (N_f=2) computations and compare the results with non perturbative determinations.

   hep-latNucl.Phys.B Proc.Suppl.(2005)·4 citations
5. 05*

   3-d lattice SU(3) free energy to four loops

   F. Di Renzo🇮🇹 · A. Mantovi🇮🇹 · V. Miccio🇮🇹 · Y. Schroder🇺🇸 · C. Torrero🇮🇹

   We report on the perturbative computation of the 3d lattice Yang-Mills free energy to four loops by means of Numerical Stochastic Perturbation Theory. The known first and second orders have been correctly reproduced; the third and fourth order coefficients are new results and the known logarithmic IR divergence in the fourth order has been correctly identified. Progress is being made in switching to the gluon mass IR regularization and the related inclusion of the Faddeev-Popov determinant.

   hep-latNucl.Phys.B Proc.Suppl.(2005)·0 citations
6. 06*

   The n_f=2 residual mass in lattice HQET to alpha^3 order

   F. Di Renzo🇮🇹 · L. Scorzato🇩🇪

   We compute the so called residual mass in Lattice Heavy Quark Effective Theory to alpha^3 order in the n_f=2 (unquenched) case. The control of this additive mass renormalization is crucial for the determination of the heavy quark mass from lattice simulations. We discuss the impact on an unquenched determination of the b-quark mass.

   hep-latNucl.Phys.B Proc.Suppl.(2005)·1 citation
7. 07*

   The QCD phase diagram at nonzero baryon, isospin and strangeness chemical potentials: Results from a hadron resonance gas model

   D. Toublan🇺🇸 · John B. Kogut🇺🇸

   We use a hadron resonance gas model to study the QCD phase diagram at nonzero temperature, baryon, isospin and strangeness chemical potentials. We determine the temperature of the transition from the hadronic phase to the quark gluon plasma phase using two different methods. We find that the critical temperatures derived in both methods are in very good agreement. We find that the critical surface has a small curvature. We also find that the critical temperature's dependence on the baryon chemical potential at zero isospin chemical potential is almost identical to its dependence on the isospin chemical potential at vanishing baryon chemical potential. This result, which holds when the chemical potentials are small, supports recent lattice simulation studies. Finally, we find that at a given baryon chemical potential, the critical temperature is lowered as either the isospin or the strangeness chemical potential are increased. Therefore, in order to lower the critical temperature, it might be useful to use different isotopes in heavy ion collision experiments.

   ↳ hep-phhep-lathep-thnucl-thPLB(2005)·65 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.