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arXiv · 2201.11064

The heavy ions are "preheated" prior to hight energy collisions

Edward Shuryak
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Abstract

The so called "isobar run" or RHIC was designed to compare a number of observables for collisions of $^{96}_{40}Zr$ with those of $^{96}_{44}Ru$, aimed at identification of $Z$-dependent effects. However, as the STAR data have shown with unprecedented accuracy, these two nuclides differ stronger than expected, producing effects larger than those depending on charge. So far, multiple studies tried to quantify their shape differences, in relation to various observables. General consensus is that these differences somehow should be related to nuclear structure, in particularly properties of the lowest excited states. Yet the precise connection between these fields -- low and high energy nuclear physics -- is still missing. In this paper I propose such a connection, via a concept of thermal density matrices of a "preheated" nuclei. The effective temperature should parameterize which set of excited states should be included in the calculations. I also suggest semiclassical "flucton" method at finite temperatures to be used to calculate thermal density matrices.

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Edward Shuryak. 2022-01-26. The heavy ions are "preheated" prior to hight energy collisions. https://arxiv.org/abs/2201.11064

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