Mon·Nov 12, 2007Monday·November 12, 2007

1. 01*

   Finite temperature Lattice QCD with two flavors of improved Wilson fermions

   V.G. Bornyakov🇷🇺 · S.M. Morozov🇷🇺 · Y. Nakamura🇩🇪 · M.I. Polikarpov🇷🇺 · G. Schierholz🇩🇪 · T. Suzuki🇷🇺

   We present results of finite temperature QCD from N_f=2 flavors of non-perturbatively improved Wilson fermions on lattices with N_t=8, 10 and 12. The transition temperature T_c is determined for the first time at lattice spacings as low as a = 0.08 fm, albeit at pion masses 1.3 < r_0 m_\pi. We furthermore compute the screening masses in various color channels at T>T_c.

   hep-latPoS(2007)·11 citations
2. 02*

   A first look at Landau-gauge propagators in G2 Yang-Mills theory

   Axel Maas🇸🇰 · Stefan Olejnik🇸🇰

   G_2 Yang--Mills theory is an interesting laboratory to investigate non-perturbative effects. On one hand, no conventional quark confinement via a linearly rising potential is present. On the other hand, its thermodynamic properties are similar to ordinary SU(N) Yang--Mills theory. Finally, it has been conjectured that gluons are removed from the physical spectrum in the same way as in SU(N) Yang--Mills theory. The last claim will be explored by determining the Landau-gauge ghost and gluon propagators, as well as the Faddeev--Popov operator eigenspectrum, in G_2 lattice gauge theory in two and three dimensions. The results are found to agree qualitatively with the SU(2) and SU(3) case. Therefore, the conjecture that Yang--Mills theories with different gauge groups are qualitatively similar on the level of their Landau gauge Green's functions is supported.

   hep-lathep-phhep-thJHEP(2008)·35 citations
3. 03*

   Mass gap in the 2D O(3) non-linear sigma model with a theta=pi term

   B. Alles🇮🇹 · A. Papa🇮🇹

   By analytic continuation to real theta of data obtained from numerical simulation at imaginary theta we study the Haldane conjecture and show that the O(3) non-linear sigma model with a theta term in 2 dimensions becomes massless at theta=3.10(5). A modified cluster algorithm has been introduced to simulate the model with imaginary theta. Two different definitions of the topological charge on the lattice have been used; one of them needs renormalization to match the continuum operator. Our work also offers a successful test for numerical methods based on analytic continuation.

   ↳ cond-mat.stat-mechcond-mat.otherhep-latPRD(2008)·54 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.