Abstract

We calculate the gluon self-energy using quark energy projectors in a general quark-gluon plasma. By separating the quark field into positive- and a negative-energy modes, the quark loop constructed with the same mode is always convergent, and the divergence appears only in the mixed loop with different modes and is medium independent. After removing the divergence in vacuum, we obtain the one-loop gluon self-energy at finite temperature, chemical potential, and quark mass without approximation. With the method of quark-loop resummation, we calculate nonperturbatively the gluon Debye mass and thermodynamic potential. In the limit of small gluon momentum in comparison with temperature, chemical potential, and quark mass, our calculation comes back to the known HTL/HDL results in literature.

Highlights

  • As an often used method in theoretical calculations, one introduces energy projectors to divide the quark field into positive- and negative-energy modes, and any Feynman diagram is separated into two groups: the pure fraction constructed from the same modes, and the mixed fraction contructed from the two modes [55,56,57,58,59,60,61]

  • The one-loop diagram plays a crucial role in nonperturbative calculations of QCD, like the approaches of hard thermal loop resummation (HTL) [83,84,85,86,87,88] and hard dense loop resummation (HDL) [89]

  • Like extremely high temperature or high baryon density, the divergence is properly removed in HTL and HDL [90,91,92]

Read more

Summary

INTRODUCTION

The properties of QCD matter at finite temperature and chemical potential, especially the deconfinement and chiral symmetry phase transitions [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26] and their realization in high-energy nuclear collisions [27,28,29,30,31,32,33,34,35,36,37,38,39] and compact stars [40,41,42,43,44,45,46,47,48,49,50,51,52,53,54], have been widely studied for decades. Like extremely high temperature or high baryon density, the divergence is properly removed in HTL and HDL [90,91,92]. Divergence problem in the calculation of the in-medium one-loop gluon self-energy at finite temperature, chemical potential, and quark mass, using the quark energy-projector method. We will see that the divergence appears only in the mixed loop and is medium independent It does not change the thermodynamic properties relative to the vacuum and can be directly removed.

ENERGY-PROJECTOR METHOD
ONE-LOOP GLUON SELF-ENERGY
T2 δab 2
Gluon loop and ghost loop
Debye mass
High-density limit
Thermodynamic potential
SUMMARY

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.