Department of Theoretical Physics, Tata Institute of Fundamental Research, Mumbai, India.
Science. 2011 Jun 24;332(6037):1525-8. doi: 10.1126/science.1204621.
Matter described by quantum chromodynamics (QCD), the theory of strong interactions, may undergo phase transitions when its temperature and the chemical potentials are varied. QCD at finite temperature is studied in the laboratory by colliding heavy ions at varying beam energies. We present a test of QCD in the nonperturbative domain through a comparison of thermodynamic fluctuations predicted in lattice computations with the experimental data of baryon number distributions in high-energy heavy ion collisions. This study provides evidence for thermalization in these collisions and allows us to find the crossover temperature between normal nuclear matter and a deconfined phase called the quark gluon plasma. This value allows us to set a scale for the phase diagram of QCD.
物质由量子色动力学（QCD）描述，这是一种强相互作用理论，当它的温度和化学势发生变化时可能会经历相变。在有限温度下的 QCD 通过在不同束能下碰撞重离子在实验室中进行研究。我们通过比较晶格计算中预测的热力学涨落与高能重离子碰撞中重子数分布的实验数据，对非微扰域中的 QCD 进行了检验。这项研究为这些碰撞中的热化提供了证据，并使我们能够找到正常核物质和称为夸克胶子等离子体的离解相之间的交叉温度。这个值使我们能够为 QCD 的相图设定一个标度。
