Tue·Oct 2, 2001Tuesday·October 2, 2001

1. 01*

   Determining hybrid content of heavy quarkonia using lattice nonrelativistic QCD

   Tommy Burch🇺🇸 · Kostas Orginos🇺🇸 · Doug Toussaint🇺🇸

   Using lowest-order lattice NRQCD to create heavy meson propagators and applying the spin-dependent interaction, $c_B^{}\frac{-g}{2m_q}\vec{\sigma }\cdot \vec{B}$, at varying intermediate time slices, we compute the off-diagonal matrix element of the Hamiltonian for the quarkonium-hybrid two-state system. Diagonalizing this two-state Hamiltonian, the admixture of hybrid ($|Q\bar{Q}g>$) in the ground state is found. We present results from a set of quenched lattices with an interpolation in quark mass to match the bottomonium spectrum.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·7 citations
2. 02*

   Abelian and Center Vortex Condensation in SU(3) Lattice Gauge Theory

   Paolo Cea🇮🇹 · Leonardo Cosmai🇮🇹

   We study the condensation of Abelian and Center vortices in SU(3) lattice gauge theory at finite temperature. We find that both vortices condense in the confined phase of the SU(3) vacuum.

   hep-lat1 citation
3. 03*

   F_B from moving B mesons

   S. Collins🇬🇧 · G. Cowan🇬🇧 · C. T. H. Davies🇬🇧 · J. Hein🇬🇧 · G. P. Lepage🇺🇸 · C. Morningstar🇺🇸 · J. Shigemitsue🇺🇸

   We show results for the B meson decay constant calculated both for B mesons at rest and those with non-zero momentum and using both the temporal and spatial components of the axial vector current. It is an important check of lattice systematic errors that all these determinations of f_B should agree. We also describe how well different smearings for the B meson work at non-zero momentum - the optimal smearing has a narrow smearing for the b quark.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·3 citations
4. 04*

   Dynamics near the critical point: the hot renormalization group in quantum field theory

   D. Boyanovsky🇺🇸 · H. J. de Vega🇫🇷

   The perturbative approach to the description of long wavelength excitations at high temperature breaks down near the critical point of a second order phase transition. We study the \emph{dynamics} of these excitations in a relativistic scalar field theory at and near the critical point via a renormalization group approach at high temperature and an $ϵ$ expansion in $d=5-ϵ$ space-time dimensions. The long wavelength physics is determined by a non-trivial fixed point of the renormalization group. At the critical point we find that the dispersion relation and width of quasiparticles of momentum $p$ is ${\omega }_p\sim p^z$ and ${\Gamma }_p\sim (z-1){\omega }_p$ respectively, the group velocity of quasiparticles $v_g\sim p^{z-1}$ vanishes in the long wavelength limit at the critical point. Away from the critical point for $T\gtrsim T_c$ we find ${\omega }_p\sim {\xi }^{-z}[1+(p\xi {)}^{2z}{]}^{1/2}$ and ${\Gamma }_p\sim (z-1){\omega }_p\frac{(p\xi {)}^{2z}}{1+(p\xi {)}^{2z}}$ with $\xi$ the finite temperature correlation length $\xi \propto |T-T_c{|}^{-\nu }$. The new \emph{dynamical} exponent $z$ results from anisotropic renormalization in the spatial and time directions. For a theory with O(N) symmetry we find $z=1+ϵ\frac{N+2}{(N+8{)}^2}+\mathcal{O}({ϵ}^2)$. Critical slowing down, i.e, a vanishing width in the long-wavelength limit, and the validity of the quasiparticle picture emerge naturally from this analysis.

   ↳ hep-phcond-mathep-lathep-th+1PRD(2002)·16 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.