RT Journal Article
T1 Energy versus centrality dependence of the jet quenching parameter q̂ at RHIC and LHC: a new puzzle?
A1 Andrés Casas, Carlota
A1 Armesto Pérez, Néstor
A1 Luzum, Matthew
A1 Salgado López, Carlos Alberto
A1 Zurita, María Pía
AB The central goal of jet quenching studies in high-energy nuclear collisions is the characterization of those QCD medium properties that are accessible by these probes. Most of the discussion in the last years has been focused on the determination of the jet quenching parameter,   q^ . We present here an extraction of this parameter using data of inclusive particle suppression at RHIC and LHC energies for different centralities. Our approach consists in fitting a K factor that quantifies the departure of this parameter from an ideal estimate,   K≡q^/(2ϵ3/4)K≡q^/(2ϵ3/4) , where   q^q^  is determined by the local medium quantities as provided by hydrodynamical calculations. We find that this K factor is larger at RHIC than at the LHC, as obtained already in previous analyses, but, surprisingly, it is almost independent of the centrality of the collision. Taken at face value, the K factor would not depend on the local properties of the medium as energy density or temperature, but on global collision quantities such as the center of mass energy. This is a very intriguing, unexpected possibility for which we cannot yet provide a clear interpretation. We also comment on the limitations of the formalism that may affect this conclusion
PB Springer
SN 1434-6044
YR 2016
FD 2016-08-26
LK http://hdl.handle.net/10347/16327
UL http://hdl.handle.net/10347/16327
LA eng
NO Andrés, C., Armesto, N., Luzum, M. et al. Eur. Phys. J. C (2016) 76: 475. https://doi.org/10.1140/epjc/s10052-016-4320-5
NO This research was supported by the European Research Council Grant HotLHC ERC2011-StG-279579;the People Programme (Marie Curie Actions) ofthe European Union’s Seventh Framework Programme FP7/2007-2013/under REA Grant Agreement #318921 (NA); Ministerio de Ciencia e Innovación of Spain under project FPA2014-58293-C2-1-P; Xunta deGalicia (Consellería de Educación)—the group is part of the StrategicUnit AGRUP2015/11. C. Andrés thanks the Spanish Ministery ofEducation, Culture and Sports for financial support (Grant FPU2013-03558)
DS Minerva
RD 28 abr 2026