Medium-induced gluon radiation is usually identified as the dominant dynam- ical mechanism underling the jet quenching phenomenon observed in heavy-ion collisions. In its actual implementation, multiple medium-induced gluon emissions are assumed to be independent, leading, in the eikonal approximation, to a Poisson distribution. Here, we introduce a medium term in the splitting probabilities so that both medium and vacuum contributions are included on the same footing in a DGLAP approach. The improvements include energy-momentum conservation at each individual splitting, medium-modified vir- tuality evolution and a coherent implementation of vacuum and medium splitting proba- bilities. Noticeably, the usual formalism is recovered when the virtuality and the energy of the parton are very large. This leads to a similar description of the suppression observed in heavy-ion collisions with values of the transport coefficient of the same order as those obtained using the quenching weights
Medium evolved fragmentation functions / Armesto, N.; Cunqueiro, L.; Salgado, C. A.; Wen-Chang, Xiang. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - (2008). [10.1088/1126-6708/2008/02/048]
Medium evolved fragmentation functions
L. Cunqueiro;C. A. Salgado;
2008
Abstract
Medium-induced gluon radiation is usually identified as the dominant dynam- ical mechanism underling the jet quenching phenomenon observed in heavy-ion collisions. In its actual implementation, multiple medium-induced gluon emissions are assumed to be independent, leading, in the eikonal approximation, to a Poisson distribution. Here, we introduce a medium term in the splitting probabilities so that both medium and vacuum contributions are included on the same footing in a DGLAP approach. The improvements include energy-momentum conservation at each individual splitting, medium-modified vir- tuality evolution and a coherent implementation of vacuum and medium splitting proba- bilities. Noticeably, the usual formalism is recovered when the virtuality and the energy of the parton are very large. This leads to a similar description of the suppression observed in heavy-ion collisions with values of the transport coefficient of the same order as those obtained using the quenching weightsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.