Simultaneous radio and optical polarimetry of GRB 191221B afterglow
Simultaneous radio and optical polarimetry of GRB 191221B afterglow
复制标题
DOI：
10.1038/s41550-022-01832-7
复制
发表时间：
2021-09
期刊：
影响因子：
14.1
通讯作者：
Y. Urata;K. Toma;S. Covino;K. Wiersema;Kuiyun Huang;J. Shimoda;Asuka Kuwata;Sota Nagao;K. Asada;H. Nagai;Satoko Takahashi;Chao-En Chung;G. Petitpas;K. Yamaoka;L. Izzo;J. Fynbo;A. de Ugarte Postigo;M. Arabsalmani;M. Tashiro
中科院分区：
文献类型：
--
作者：
Y. Urata;K. Toma;S. Covino;K. Wiersema;Kuiyun Huang;J. Shimoda;Asuka Kuwata;Sota Nagao;K. Asada;H. Nagai;Satoko Takahashi;Chao-En Chung;G. Petitpas;K. Yamaoka;L. Izzo;J. Fynbo;A. de Ugarte Postigo;M. Arabsalmani;M. Tashiro
伽玛射线暴（GRBs）是宇宙中最明亮的瞬变现象，被用作早期恒星，引力波对应物和无碰撞冲击物理的探测器。尽管在单个波长的伽玛暴偏振测量研究中发现了激发发射和余辉的有趣特性，但还没有进行协调的多波长测量。在这里，我们报告了与典型的长GRB 191221B相关的余辉在光学和无线电波段的第一次协调同时偏振测量。我们的观测成功地捕获了不受同步加速器自吸收影响的射电发射，并表明与光学发射相比，射电发射在射电波段是去极化的。我们同时进行的偏振角测量和时间偏振监测表明，冷电子的存在使伽马射线暴余辉的射流动能估计增加了4倍以上。进一步协调的多波长偏振运动将提高我们对各种类型grb发射区域的总射流能量和磁场结构的理解，这是理解其祖系统的质量尺度和无碰撞冲击物理所必需的。
Gamma-ray bursts (GRBs) are the most luminous transients in the universe and are utilized as probes of early stars, gravitational wave counterparts and collisionless shock physics. In spite of studies on polarimetry of GRBs in individual wavelengths that characterized intriguing properties of prompt emission and afterglow, no coordinated multi-wavelength measurements have yet been performed. Here we report the first coordinated simultaneous polarimetry in the optical and radio bands for the afterglow associated with the typical long GRB 191221B. Our observations successfully caught the radio emission, which is not affected by synchrotron self-absorption, and show that the emission is depolarized in the radio band compared with the optical one. Our simultaneous polarization angle measurement and temporal polarization monitoring indicate the existence of cool electrons that increase the estimate of jet kinetic energy by a factor of more than 4 for this GRB afterglow. Further coordinated multi-wavelength polarimetric campaigns would improve our understanding of the total jet energies and magnetic field configurations in the emission regions of various types of GRBs, which are required to comprehend the mass scales of their progenitor systems and the physics of collisionless shocks.