EAPSI: Demystifying the Observed Gamma Ray Burst Tracking Between the Peak Energy and Luminosity

伽马射线暴（GRBs）是宇宙中能量最高的事件之一。然而，关于这些天体还有很多未知的地方，比如它们的准直流出或射流结构的关键信息。这些信息很难推断，因为GRB观测台无法提供与GRB相对于探测器的方向有关的信息。本项目将通过探索GRB探测的时间分辨光谱峰值能量和光曲线之间的观测跟踪的起源，研究确定GRB几何方向难以捉摸信息的方法。运行GRB辐射的模拟将使我们能够确定给定GRB的跟踪关系和视角之间的相关性。这个项目将由长崎茂博博士在理化研究所进行。这次合作将建立在该小组先前对射流结构的研究基础上，并允许使用grb的磁流体动力学模拟，这将使我们能够充分探索峰值能量与光度之间的关系。利用后处理的蒙特卡洛辐射传输代码进行GRB辐射传输的模拟。这些密码将每个光子分散到流出流中，直到光子自由逃逸。这允许在模拟GRB的不同视角下，以最小的假设计算光曲线和光谱。提出了一种定量测量峰值能量和光曲线强度之间跟踪关系的方法。这将有助于确定跟踪行为的特征如何随着视角的变化而变化。该奖项由美国国家科学基金会和日本科学促进会共同资助，隶属于东亚和太平洋暑期研究所项目，支持一名美国研究生进行暑期研究。

Gamma Ray Bursts (GRBs) are some of the most energetic events in the universe. However, much is unknown about these objects such as critical information about the structure of their collimated outflow or jet. This information is hard to deduce due to the fact that GRB observatories are unable to provide information related to the orientation of the GRB in relation to the detector. This project will investigate a means to determining the elusive information of GRB geometrical orientation by exploring the origin of the observed tracking between the time resolved spectral peak energy and the light curve of a GRB detection. Running simulations of GRB radiation will allow us to identify a correlation between the tracking relation and the viewing angle for a given GRB. This project will be conducted at RIKEN with Dr. Shigehiro Nagataki. This collaboration will build upon previous studies conducted by the group on jet structure as well as allow for the use of magnetohydrodynamic simulations of GRBs which will allow us to fully explore the relation between the peak energy and the luminosity. The simulations of GRB radiation transfer will be conducted with post-processing Monte Carlo Radiation Transfer codes. These codes individually scatter each photon in an outflow until it freely escapes. This allows for light curves and spectra to be calculated at various viewing angles of the simulated GRB with minimal assumptions being made. A quantitative way to measure the tracking between the peak energy and the light curve intensity will be developed. This will aid in determining how the characteristics of tracking behavior changes as a function of viewing angle.This award, under the East Asia and Pacific Summer Institutes program, supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.