Jet-Quenching Parameter $hat{q}$ in the Nonperturbative Region

Seung-il NAM*
2016 New Physics Sae Mulli  
We investigate the jet-quenching parameterq for the quark-gluon plasma (QGP) for Nc = 3, defined nonperturbatively with the Wilson loop in the light-cone (LC) coordinate, at finite temperature (T ). Considering the effective static (heavy) quark-antiquark potential VQ Q = σL + C − A/L, where L indicates the LC transverse separation between the quarks, we obtainq ≈ 8VQ Q /L 2 . The T dependences for L and other relevant parameters are extracted from the T -dependent instanton (trivial-holonomy
more » ... (trivial-holonomy caloron) length parameters and the lattice QCD data. By choosing L ≈ a ≈ρT , in which a andρT denote the lattice spacing and the T -dependent average (anti)instanton size, respectively, we acquire numerically thatq = (5 ∼ 25) GeV/fm for T = (0 ∼ 0.6) GeV, and these values are well consistent with other estimations from AdS/CFT and experimental analyses. It turns out thatq is produced almost by the Coulomb and constant potentials of VQ Q . We also observe that the ratio T 3 /q turns into being saturated to ∼ 4.45 × 10 −2 for T 0.4 GeV, indicating the strongly-coupled QGP, andq behaves proportionally to T 3 for high T .
doi:10.3938/npsm.66.673 fatcat:xh5nlmucjvdploglmptjue6co4