γ射线暴光变曲线的研究

A Study of Variable Light Curves of GRB

γ射线暴的光变曲线复杂多变,普遍认为是由内激波产生.由相对论运动学效应导出高速运动激波层发射的光子数与观测者接收到的光子数之间的转换关系,再运用内激波辐射的角度扩展得到单个脉冲的曲线方程和形状,其形状为典型的快上升指数下降.进而在合理的参数下用多壳层的连续碰撞模型对γ射线暴的一些观测光变曲线进行拟合,取得较好效果,由此可以解释更多类型的γ射线暴的光变曲线.

Most of GRB have a highly variable profile with time.It is believed generally that the observed prompt structure arise from the internal shocks which could occur when a rapid shell catches up a slower one and collide with it.The electrons with- in shock shell are heated by the shocks and internal energy is then radiated via synchro- tron and inverse Compton scattering.Based on relativistic kinematics,a transform rela- tion between the photon number of emission of shock shell which moves with ultra-rela- tivistic speed and the photon number received by observer has been derived.Applying the angular spreading of internal shock's emission,the curve function and the profile of light pulse are obtained.The single pulse has a typical shape of fast rise exponential de- cay.At last,using the model of multiple collisions of consequent shells and reasonable parameters,the observed variable light curves of GRB are simulated and the better re- sults are acquired.Therefore one can explain more kinds of light curves.