论文标题
从相对论重离子碰撞的晚期开始的非平衡方法用于光子发射
A Non-Equilibrium Approach to Photon Emission from the Late Stages of Relativistic Heavy-Ion Collisions
论文作者
论文摘要
根据有效的手性场理论，已经计算出辐射散射过程中光子产生的横截面。对于$π+ρ\至π+γ$和$π+π\至ρ+γ$过程，这些横截面已实现为一种新型的HADRONIC转运方法（SMASH），该方法适用于低和中等能量的碰撞。通过系统地将热光子速率与理论期望进行比较，可以验证实施。将我们获得的光子速率与以前的工作进行了比较，在这种情况下，发现由$ω$介导的散射过程对总光子产生产生了显着贡献。最后，研究了考虑$ρ$梅森的有限宽度的影响，并观察到低能量区域的光子产生显着增强。这项工作是在混合流体动力学+传输方法中对光子发射一致治疗的第一步。下一步是对直接光子流量拼图分辨率的习惯性的量化，可以应用于识别耐药燃烧室中的平衡和非平衡效应。
Cross sections for photon production in hadronic scattering processes have been calculated according to an effective chiral field theory. For $π+ ρ\to π+ γ$ and $π+ π\to ρ+ γ$ processes, these cross sections have been implemented into a novel hadronic transport approach (SMASH), which is suitable for collisions at low and intermediate energies. The implementation is verified by systematically comparing the thermal photon rate to theoretical expectations. The photon rates we obtain are compared to previous works, where scattering processes mediated by $ω$ mesons are found to contribute significantly to the total photon production. Finally, the impact of considering the finite width of the $ρ$ meson is investigated, and a significant enhancement of photon production in the low-energy region is observed. This work is the first step towards a consistent treatment of photon emission in hybrid hydrodynamics+transport approaches. The quantification of the importance of the hadronic stage for the resolution of the direct photon flow puzzle is a next step and can be applied to identify equilibrium and non-equilibrium effects in the hadronic afterburner.
