Anisotropy of Low Energy Direct Photons in Relativistic Heavy Ion Collisions

摘要: We investigate the behavior of low energy photons radiated by deceleration processes two colliding nuclei in relativistic heavy ion collisions using Wigner function approach for electromagnetic radiation fields. The angular distribution reveals information initial geometric configurations. Such a property is reflected anisotropic parameter $v_{2}$, showing an increasing $v_{2}$ as decreases, which qualitatively different from hadrons produced collisions.