Year: 2014
Type: article
Abstract: A perturbative QCD based jet tomographic Monte Carlo model, CUJET2.0, is presented to predict jet quenching observables in relativistic heavy ion collisions at RHIC/BNL and LHC/CERN energies. This model generalizes the DGLV theory of flavor dependent radiative energy loss by including multi-scale running strong coupling effects. It generalizes CUJET1.0 by computing jet path integrations though more realistic 2 + 1D transverse and longitudinally expanding viscous hydrodynamical fields contrained by fits to low p T flow data. The CUJET2.0 output depends on three control parameters, (α max , f E , f M ), corresponding to an assumed upper bound on the vacuum running coupling in the infrared and two chromo-electric and magnetic QGP screening mass scales (f E μ(T ), f M μ(T )) where μ(T ) is the 1-loop Debye mass. We compare numerical results as a function of α max for pure and deformed HTL dynamically enhanced scattering cases corresponding to (f E = 1, 2, f M = 0) to data of the nuclear modification factor, R (p T , ϕ; $$ \sqrt{s}, b $$ ) for jet fragment flavors f = π, D, B, e at $$ \sqrt{s} $$ = 0.2 − 2.76 ATeV c.m. energies per nucleon pair and with impact parameter b = 2.4, 7.5 fm. A χ 2 analysis is presented and shows that R data from RHIC and LHC are consistent with CUJET2.0 at the χ 2 /d.o.f < 2 level for α max = 0.23 − 0.30. The corresponding $$ \widehat{q} $$ (E jet , T )/T 3 effective jet transport coefficient field of this model is computed to facilitate comparison to other jet tomographic models in the literature. The predicted elliptic asymmetry, v 2(p T ; $$ \sqrt{s} $$ , b) is, however, found to significantly underestimated relative to RHIC and LHC data. We find the $$ {\chi}_{v_2}^2 $$ analysis shows that v 2 is very sensitive to allowing even as little as 10% variations of the path averaged α max along in and out of reaction plane paths.
Source: Journal of High Energy Physics
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Awards: G1079818582, G1143651532, G1286236842, G1321567321, G222768804, G2857863752, G3083819904, G365575497, THEORY OF ULTRA-DENSE MATTER AND THE DYNAMICS OF HIGH ENERGY INTERACTIONS INVOLVING NUCLEI, G42916606, THEORY OF ULTRA-DENSE MATTER AND THE DYNAMICS OF HIGH ENERGY INTERACTIONS INVOLVING NUCLEI, G5414694606, G7354628648, G969889393
OpenAlex ID: W2027194755