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arXiv · 2409.07685

Optimal collision-energy range for realizing macroscopic high-baryon-density matter

Hidetoshi Taya·Asanosuke Jinno·Masakiyo Kitazawa·Yasushi Nara
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Abstract

We investigate the volume and lifetime of the high baryon-density matter created in heavy-ion collisions and estimate the optimal collision-energy range to realize the high baryon-density region over a large spacetime volume. We simulate central collisions of gold ions for the center-of-mass energy per nucleon pair $\sqrt{s_{NN}}=2.4 - 19.6\;{\rm GeV}$ with a microscopic transport model JAM. We discover that the optimal range is around $\sqrt{s_{NN}}=3 - 5\;{\rm GeV}$, where a baryon density exceeding three times the normal nuclear density is realized with a substantially large spacetime volume. Higher and lower energies are disfavored due to short lifetime and low density, respectively. We also point out that event-by-event fluctuations of the spacetime density profile are large, indicating the importance of the event selection in the experimental analysis.

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Hidetoshi Taya, Asanosuke Jinno, Masakiyo Kitazawa, Yasushi Nara. 2024-09-12. Optimal collision-energy range for realizing macroscopic high-baryon-density matter. https://doi.org/10.1103/rpxm-fql8

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