Parkes observations for project P1171 semester 2023OCTS_02

The origin of Fast Radio Bursts (FRBs) is still unclear with a plethora of theoretical models for their origin. Several models predict associated multi-wavelength emission, but previous searches for optical, X-ray or gamma-ray counterparts of FRBs have not led to any detection. The Galactic magnetar SGR 1935+2154A has been observed to simultaneously emit FRB-like bursts and X-ray flares, which suggests that also extragalactic FRB sources may exhibit X-ray counterparts. Because of the high cost of X-ray satellites and in face of the relatively low FRB detection probability in their small field of view, coordinated radio and X-ray observations are logistically very difficult to set up. We propose a new approach using the X-ray satellite XMM-Newton and the Parkes/Murriyang radio telescope to put constraints on the theoretical models: We aim to conduct shadowing observations with the Parkes telescope to search for new FRBs in fields that are simultaneously covered by XMM-Newton. We hereby target regular XMM observations of nearby (low-z) galaxies, to increase our detection chances of possibly associated X-ray emission. In case of an FRB detection in the radio band, we will have guaranteed simultaneous X-ray coverage and will get detailed information about the associated X-ray spectrum and light curve since all XMM-Newton data will become public a year after the observation.

快速射电暴（Fast Radio Bursts，FRBs）的起源至今仍未明晰，学界已提出诸多相关理论模型。部分模型预言其存在对应的多波段辐射，但此前针对快速射电暴的光学、X射线或伽马射线对应体的搜寻均未取得任何探测结果。

银河系磁星SGR 1935+2154A已被观测到同时爆发类快速射电暴脉冲与X射线耀发，这暗示河外快速射电暴源或许也会产生X射线对应体。由于X射线卫星运行成本高昂，且其视场狭小导致快速射电暴的探测概率相对较低，因此协调开展射电与X射线观测在实施组织上难度极大。

我们提出一种全新方案，借助XMM-牛顿卫星（XMM-Newton）与帕克斯/穆里扬射电望远镜（Parkes/Murriyang radio telescope）对快速射电暴的理论模型施加约束：我们计划利用帕克斯望远镜在XMM-牛顿卫星同时覆盖的天区中开展同步搜寻观测，以探测新的快速射电暴。本次观测的目标为邻近（低红移）星系的常规XMM-牛顿观测项目，以此提升探测到潜在对应X射线辐射的概率。

若在射电波段探测到快速射电暴，我们将获得确定的同时段X射线观测数据；且由于所有XMM-牛顿卫星的观测数据会在观测结束一年后公开，我们还将获取对应X射线能谱与光变曲线的详细信息。