Constraint fitting of experimental data with a jet quenching model embedded in a hydrodynamical bulk medium

Néstor Armesto (1) , Matteo Cacciari (2) , Tetsufumi Hirano (3) , James L Nagle (4) , Carlos A Salgado (1, 2)

1 IGFAE
2 LPTHE - Laboratoire de Physique Théorique et Hautes Energies
3 Department of Physics
4 University of Colorado [Boulder]

We present a global fit to single- and double-inclusive suppression data of high-p T particles in central Au+Au collisions at top RHIC energy. We also include in this analysis data on heavy quarks via their D and B meson semi-leptonic decays (i.e. non-photonic electrons). The analysis is based on the parton quenching weights for medium-induced gluon radiation computed in the BDMPS approximation then embedded in a hydrodynamical description of the bulk medium. Our results indicate that values of the transport coefficient more than four times larger than perturbative estimates are preferred by experimental data. This confirms previous calculations based on simpler implementations of the medium geometry or only the single-inclusive suppression. We also comment on the statistical compatibility of the heavy quark data within a radiative only energy loss scenario, and on the sensitivity of the results to nuclear modification of the parton distribution functions (PDFs) and to assumptions on the energy loss during times in the collision prior to the hydrodynamical behavior.

Mots clés: Physical Sciences

Domaines: Physique des Hautes Energies - Phénoménologie [hep-ph]; Physique Nucléaire Expérimentale [nucl-ex]; Physique Nucléaire Théorique [nucl-th]

Néstor Armesto, Matteo Cacciari, Tetsufumi Hirano, James L Nagle, Carlos A Salgado. Constraint fitting of experimental data with a jet quenching model embedded in a hydrodynamical bulk medium. Journal of Physics G: Nuclear and Particle Physics, 2010, 37 (2), pp.25104. ⟨10.1088/0954-3899/37/2/025104⟩. ⟨hal-00600789⟩