论文标题
中等能源重型离子碰撞中硬光子和游离核子的方位角各向异性和多重性
Azimuthal anisotropy and multiplicities of hard photons and free nucleons in intermediate-energy heavy-ion collisions
论文作者
论文摘要
各向异性流可以提供重型离子碰撞中进化动力学的重要信息。对定向流量$ v_1 $和椭圆流的系统研究$ v_2 $硬光子和免费核子，以$^{40} $ ca+$+$^{40} $ ca的碰撞在依赖依赖的量子量子分子动力学（IQMD）模型的框架中进行。该研究首先揭示了中间能量重离子碰撞中发出的热光子具有定向和椭圆流的行为。中央碰撞中热光子的$ v_1 $和$ v_2 $事件能量依赖性的有趣现象也证实，它可以被视为进化动力学的良好探针。此外，还研究了硬光子和游离核子的多重性及其相关性。我们发现直接光子发射与游离核子的发射呈正相关，但是，存在带有游离核子的热光子的抗相关性。
Anisotropic flow can offer significant information of evolution dynamics in heavy-ion collisions. A systematic study of the directed flow $v_1$ and elliptic flow $v_2$ of hard photons and free nucleons is performed for $^{40}$Ca+$^{40}$Ca collisions in a framework of isospin dependent quantum molecular dynamics (IQMD) model. The study firstly reveals that thermal photons emitted in intermediate-energy heavy-ion collisions have the behaviors of directed and elliptic flows. The interesting phenomena of incident energy dependence of $v_1$ and $v_2$ for thermal photons in central collisions also confirmed that it can be regarded as a good probe of evolution dynamics. Moreover, the multiplicities of hard photons and free nucleons and their correlation are also investigated. We find that direct photon emission is positively related to free nucleons emission, however, there exists an anti-correlation for thermal photons with free nucleons.
