Angular variation of hard back-to-back hadron suppression in heavy-ion collisions

作者：Renk Thorsten^*

来源：Physical Review C, 2008, 78(3): 034904.

DOI：10.1103/PhysRevC.78.034904

The basic idea of jet tomography is to infer information about the density evolution of the medium created in heavy-ion (A-A) collisions by studying the suppression of hard probes in an A-A environment as compared to the baseline process known from proton-proton (p-p) collisions. The suppression of back-to-back correlations in heavy-ion collisions allows, due to a different geometrical bias, a view into the medium that is qualitatively different from the one offered by single-hadron suppression. A control parameter for the suppression corresponding to a systematic variation of in-medium path lengths and densities can be obtained by studying collisions at finite impact parameter b. Asystematic variation of path length can then be introduced by studying the suppression pattern as a function of the angle phi with the reaction plane. Using a three-dimensional hydrodynamic evolution model for the medium and a Monte Carlo model that has been shown to successfully reproduce the measured suppression of back-to-back correlations in central collisions of Au-Au at 200A GeV, we compute the suppression as a function of f for b of 2.4, 4.5, 6.3, and 7.5 fm. Given that this involves variations in both control parameters b and f, a comparison with data should eventually allow one to place strong constraints on the combination of the energy loss model and the medium evolution model.

• 出版日期2008-9