ترغب بنشر مسار تعليمي؟ اضغط هنا

Anisotropic Lattice and Its Application to Quark Gluon Plasma

62   0   0.0 ( 0 )
 نشر من قبل Sunao Sakai
 تاريخ النشر 2001
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We have studied the link-integration method for the improved actions. With this method the $eta$ parameter in the medium to strong coupling regions is obtained. Effects of the self-energy terms for the $eta$ parameters are small in the regions of $beta$ and $eta$ studied. After these investigations, the anisotropic lattice is used for the calculation of transport coefficients of the quark gluon plasma.



قيم البحث

اقرأ أيضاً

The thesis contains studies of properties quark-gluon plasma, using some non-perturbative techniques. It contains a brief introduction of quark-gluon plasma (QGP) and discussion on various signatures along with a motivation for this thesis work. It p resents the basic mathematical tools and ingredients required for the thesis, i.e. basics of QCD, Imaginary and Real Time Formalism, Hard Thermal Loop perturbation theory (HTLpt), Gribov-Zwanziger (GZ) action, the Correlation Function along with the Spectral Function and Operator Product Expansion (OPE) and QCD in magnetized medium. OPE is used to compute the dilepton rate in intermediate mass range by incorporating the non-perturbative dynamics of QCD through the inclusion of non-vanishing quark and gluon condensates in combination with the Green functions in momentum space. Also the magnetic scale (g^2T) in the HTL perturbation theory, related to the confining properties of the QCD is taken into account using the GZ action through a mass parameter, which reflects a new space-like quark mode in the collective excitation. The impact of this new exciting mode on the DPR has been studied and its important consequences has been discussed. A hot magnetized medium introduces another scale in the system in addition to temperature. Electromagnetic spectral properties and DPR are studied completely analytically in presence of both strong and weak background magnetic fields at finite temperature. The Debye screening in a hot and magnetized medium has been studied which reveals some of the intriguing properties of the medium in presence of both strong and weak magnetic field. Also an important quantity that characterizes the QGP, namely quark number susceptibility has been investigated. Most of the non-perturbative results discussed in this thesis are compared with those of perturbative ones and lattice QCD.
148 - O. Philipsen , M. Tassler 2009
We reconsider a plasma with an anisotropy imposed on the momentum distribution of the system and study the real time static potential for quarkonia. The distribution function is normalised so as to preserve the particle number in an ideal gas, as req uired in the Keldysh-Schwinger formalism. In contrast to recent findings without this normalisation, a weak anisotropy does not lead to an increase in the melting temperature for bound states. To test for the maximal effect, we also investigate a gluonic medium in the limit of an asymptotically strong anisotropy. The spectral function of quarkonium is calculated for this case and found to be in remarkable agreement with the corresponding results for an isotropic medium.
We study the electromagnetic (e.m.) conductivity of QGP in a magnetic background by lattice simulations with $N_f = 2+1$ dynamical rooted staggered fermions at the physical point. We study the correlation functions of the e.m.~currents at $T=200,,250 $,MeV and use the Tikhonov approach to extract the conductivity. This is found to rise with the magnetic field in the direction parallel to it and to decrease in the transverse direction, giving evidence for both the Chiral Magnetic Effect and the magnetoresistance phenomenon in QGP. We also estimate the chiral charge relaxation time in QGP.
We calculate the yield of lepton pair production from jet-plasma interaction where the plasma is anisotropic in momentum space. We compare both the $M$ and $p_T$ distributions from such process with the Drell-Yan contribution. It is observed that the invariant mass distribution of lepton pair from such process dominate over the Drell-Yan up to $3$ GeV at RHIC and up to $10$ GeV at LHC. Moreover, it is found that the contribution from anistropic quark gluon plasma (AQGP) increases marginally compared to the isotropic QGP. In case of $p_T$-distribution we observe an increase by a factor of $3-4$ in the entire $p_T$-range at RHIC for AQGP. However, at LHC the change in the $p_T$-distribution is marginal as compared to the isotropic case.
127 - L. Levkova , C. DeTar 2013
Using numerical simulations of lattice QCD we calculate the effect of an external magnetic field on the equation of state of the quark-gluon plasma. The results are obtained using a Taylor expansion of the pressure with respect to the magnetic field for the first time. The coefficients of the expansion are computed to second order in the magnetic field. Our setup for the external magnetic field avoids complications arising from toroidal boundary conditions, making a Taylor series expansion straightforward. This study is exploratory and is meant to serve as a proof of principle.
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