Mon·Sep 12, 2005Monday·September 12, 2005

1. 01*

   String tensions and deconfinement transition in the SU(4) center vortex model

   Michael Engelhardt🇺🇸

   A center vortex model for the infrared sector of SU(4) Yang-Mills theory is constructed such as to reproduce both the ratio between the zero-temperature quark and diquark string tensions known from lattice Yang-Mills theory, as well as the properties of the deconfinement transition. On this basis, the temperature dependence of the spatial quark and diquark string tensions is predicted. Though still phenomenologically viable, details of the construction of the SU(4) center vortex model corroborate previous arguments that modeling infrared Yang-Mills dynamics purely in terms of vortex world-surface characteristics may become less appropriate as the number of colors is increased.

   hep-latPoS(2006)·1 citation
2. 02*

   Lattice and renormalons in heavy quark physics

   Antonio Pineda🇪🇸

   Perturbative expansions of QCD observables in powers of ${\alpha }_s$ are believed to be asymptotic and non-Borel summable due to the existence of singularities in the Borel plane (renormalons). This fact is connected with the factorization of scales (which is inherent to QCD and asymptotic freedom) and jeopardizes the convergence of the perturbative expansion and the accurate determination of power-suppressed corrections. This problem is more acute for physical systems composed by one or more heavy quarks. In lattice regulations, it reflects on the appearance of power-like divergences in the inverse of the lattice spacing for a series of quantities ($\bar{\Lambda }$, gluelump masses, the singlet and hybrid potentials, ...) making that the continuum limit can not be reached for them. Nevertheless, all these problems are solved within the framework of effective field theories with renormalon substraction. This allows us to obtain convergent perturbative series and to unambiguously define power corrections. In particular, one can connect with lattice results. Remarkably enough the dependence on the lattice spacing can be predicted by perturbation theory. This framework has been applied to the prediction of the gluelump masses and the singlet and octet (hybrid) potentials at short distances, as well as to their comparison with lattice simulations. Overall, very good agreement with data is obtained.

   hep-lathep-phPoS(2006)·5 citations
3. 03*

   Hadronic decays

   C. Michael🇬🇧

   Hadronic decays and transitions are a key ingredient of hadronic physics. I discuss how hadronic decays can be explored in lattice gauge theory and review studies undertaken. I also discuss the impact of decays on masses and how lattice studies can explore the nature of a hadronic state: namely whether it is a molecular or quark-antiquark state. A brief discussion of lattice exploration of pentaquark states is presented.

   hep-latPoS(2006)·18 citations
4. 04*

   Study of the systematic errors in the calculation of renormalization constants of the topological susceptibility on the lattice

   B. Alles (INFN Pisa)🇮🇹 · M. D'Elia (U. Genova)🇮🇹 · A. Di Giacomo (U. Pisa)🇮🇹 · C. Pica (U. Pisa)🇮🇹

   We present a study of the systematic effects in the nonperturbative evaluation of the renormalization constants which appear in the field-theoretical determination of the topological susceptibility in pure Yang-Mills theory. The study is performed by computing the renormalization constants on configurations that have been calibrated by use of the Ginsparg-Wilson formalism and by cooling.

   hep-latPoS(2006)·5 citations
5. 05*

   Interaction studies of a heavy-light meson-baryon system

   M. S. Cook🇺🇸 · H. R. Fiebig (the LHP Collaboration)🇺🇸

   We study time correlation functions of operators representing heavy-light K-Lambda like systems at various relative distances r. The heavy quarks, one in each hadron, are treated as static. An anisotropic and asymmetric lattice is used with Wilson fermions. Our goal is to extract an adiabatic potential and thus learn about the physics of the five-quark system viewed as an hadronic molecule.

   hep-latPoS(2006)·1 citation

* 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.