2026-10-23 中国科学院（CAS）
The phase diagram of nuclear matter and the evolution of the universe. (Image by YONG Gaochan)
＜関連情報＞
- https://english.cas.cn/newsroom/research-news/202610/t20261026_1209388.shtml
- https://www.sciencedirect.com/science/article/pii/S0370269326008816
バリオン豊富なAu+Au衝突におけるパートンダイナミクスに対するストレンジクォーク数依存応答 Strange-quark-number-dependent response to partonic dynamics in baryon-rich Au+Au collisions
Di Zhao,Xun Zhu,Gao-Chan Yong
Physics Letters B Available online: 6 October 2026
DOI:https://doi.org/10.1016/j.physletb.2026.141031
Abstract
We identify a strange-quark-number-dependent hierarchy in the response to explicit partonic dynamics by comparing PHSD5.2 with its hadron–string limit in baryon-rich Au+Au collisions at √sNN=3.0–7.2 GeV. Crossing the local conversion threshold alone does not ensure a visible final-state signal: abundant-hadron flow changes little at 3–4.5 GeV, whereas the fractional yield response becomes ordered at 6.2–7.2 GeV, reaching S|s|=1≃0.2–0.3, S|s|=2≃0.65, and S|s|=3≃0.93 at 7.2 GeV. The hierarchy is consistent with an enlarged recombination phase space for strange constituents released from different pre-hadronic sources, but does not by itself establish an increase in the total s+s¯ abundance or stronger strange-quark clustering. Since SX is a model-defined response rather than a direct observable, matched excitation functions of Ξ−/Λ and Ω−/Λ, together with high-mT proton elliptic flow, provide experimentally accessible discriminants between the predicted PHSD and HSD dynamics.
