Physics Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
Phys Rev Lett. 2013 Aug 23;111(8):082301. doi: 10.1103/PhysRevLett.111.082301.
Appropriate combinations of up to fourth order cumulants of net strangeness fluctuations and their correlations with net baryon number and electric charge fluctuations, obtained from lattice QCD calculations, have been used to probe the strangeness carrying degrees of freedom at high temperatures. For temperatures up to the chiral crossover, separate contributions of strange mesons and baryons can be well described by an uncorrelated gas of hadrons. Such a description breaks down in the chiral crossover region, suggesting that the deconfinement of strangeness takes place at the chiral crossover. On the other hand, the strangeness carrying degrees of freedom inside the quark gluon plasma can be described by a weakly interacting gas of quarks only for temperatures larger than twice the chiral crossover temperature. In the intermediate temperature window, these observables show considerably richer structures, indicative of the strongly interacting nature of the quark gluon plasma.
从格点 QCD 计算中得到的净奇异波动的四阶累积量及其与净重子数和电荷波动的相关性的适当组合，已被用于在高温下探测携带奇异数的自由度。在温度达到手征相变之前，奇异介子和重子的独立贡献可以很好地用强相互作用的强子气体来描述。在手征相变区域，这种描述会失效，这表明在相变温度下，奇异数的退禁闭发生了。另一方面，在手征相变温度的两倍以上的温度下，夸克-胶子等离子体中的携带奇异数的自由度可以用弱相互作用的夸克气体来描述。在中间温度窗口，这些可观测量表现出相当丰富的结构，表明了夸克-胶子等离子体的强相互作用性质。
