ترغب بنشر مسار تعليمي؟ اضغط هنا

Heavy Quarkonia beyond Deconfinement and Real Time Lattice Simulations

362   0   0.0 ( 0 )
 نشر من قبل Marcus R. Tassler
 تاريخ النشر 2008
  مجال البحث
والبحث باللغة English
 تأليف M. Tassler




اسأل ChatGPT حول البحث

Since the initial investigation by Matsui and Satz heavy quark bound states at finite temperature have been subject to numerous studies. The derivation of a finite-temperature potential from first principles was attempted only recently however, by generalising the Schroedinger equation which is successfully employed for the description of quarkonia at zero temperature to a thermal setting. In this note the finite-temperature static potential is derived to leading order using resummed perturbation theory. The modification of the heavy quarkonium spectral function by an imaginary part of the potential appearing at finite temperature is discussed. Additionally, the extent of possible corrections due to non-perturbative processes is assessed by employing real-time lattice techniques based on kinetic theory.

قيم البحث

اقرأ أيضاً

We report on recent results for the spectrum of heavy quarkonia. Using coarse and anisotropic lattices we achieved an unprecedented control over statistical and systematic errors for higher excited states such as exotic hybrid states. In a parallel s tudy on isotropic lattices we also investigate the effect of two dynamical flavours on the spin structure of charmonium and bottomonium for several symmetric lattices.
Recently, a finite-temperature real-time static potential has been introduced via a Schrodinger-type equation satisfied by a certain heavy quarkonium Greens function. Furthermore, it has been pointed out that it possesses an imaginary part, which ind uces a finite width for the tip of the quarkonium peak in the thermal dilepton production rate. The imaginary part originates from Landau-damping of low-frequency gauge fields, which are essentially classical due to their high occupation number. Here we show how the imaginary part can be measured with classical lattice gauge theory simulations, accounting non-perturbatively for the infrared sector of finite-temperature field theory. We demonstrate that a non-vanishing imaginary part indeed exists non-perturbatively; and that its value agrees semi-quantitatively with that predicted by Hard Loop resummed perturbation theory.
We investigate the QCD phase diagram based on the strong coupling expansion of the lattice QCD with one species of the staggered fermions at finite temperature (T) and chemical potential (mu). We analytically derive an effective potential including b oth chiral and deconfinement (Z_3) dynamics with finite coupling effects in mean-field approximations. We focus on Polyakov loop properties in whole T-mu plane, and study relations between the chiral and deconfinement crossovers. At a fixed large mu, sequencial rapid variations of the Polyakov loop are observed with increasing T. It is natural to interprete them as the chiral induced and Z_3 induced deconfinement crossovers.
We study the temperature dependence of bottomonium for temperatures in the range $0.4 T_c < T < 2.1 T_c$, using nonrelativistic dynamics for the bottom quark and full relativistic lattice QCD simulations for $N_f=2$ light flavors on a highly anisotro pic lattice. We find that the $Upsilon$ is insensitive to the temperature in this range, while the $chi_b$ propagators show a crossover from the exponential decay characterizing the hadronic phase to a power-law behaviour consistent with nearly-free dynamics at $T simeq 2 T_c$.
We study the spectral properties of a highly occupied non-Abelian non-equilibrium plasma appearing ubiquitously in weak coupling descriptions of QCD matter. The spectral function of this far-from-equilibrium plasma is measured by employing linear res ponse theory in classical-statistical real-time lattice Yang-Mills simulations. We establish the existence of transversely and longitudinally polarized quasiparticles and obtain their dispersion relations, effective mass, plasmon frequency, damping rate and further structures in the spectral and statistical functions. Our new method can be interpreted as a non-perturbative generalization of hard thermal loop (HTL) effective theory. We see indications that our results approach leading order HTL in the appropriate limit. The method can also be employed beyond the range of validity of HTL.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا