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arXiv · 1404.4394

Nuclear modification factor in intermediate-energy heavy-ion collisions

M. Lv·Y. G. Ma·G. Q. Zhang·J. H. Chen·D. Q. Fang
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Abstract

The transverse momentum dependent nuclear modification factors (NMF), namely $R_{CP}$, is investigated for protons produced in Au + Au at 1$A$ GeV within the framework of the isospin-dependent quantum molecular dynamics (IQMD) model. It is found that the radial collective motion during the expansion stage affects the NMF at low transverse momentum a lot. By fitting the transverse mass spectra of protons with the distribution function from the Blast-Wave model, the magnitude of radial flow can be extracted. After removing the contribution from radial flow, the $R_{CP}$ can be regarded as a thermal one and is found to keep unitary at transverse momentum lower than 0.6 GeV/c and enhance at higher transverse momentum, which can be attributed to Cronin effect.

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M. Lv, Y. G. Ma, G. Q. Zhang, J. H. Chen, D. Q. Fang. 2014-04-16. Nuclear modification factor in intermediate-energy heavy-ion collisions. https://doi.org/10.1016/j.physletb.2014.04.025

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