Gamma-Ray Burst Polarization: Limits from RHESSI Measurements
Gamma-Ray Burst Polarization: Limits from RHESSI Measurements
复制标题
DOI：
10.1086/423163
复制
发表时间：
2004-05
期刊：
影响因子：
--
通讯作者：
C. Wigger;W. Hajdas;K. Arzner;M. Güdel;A. Zehnder
中科院分区：
文献类型：
--
作者：
C. Wigger;W. Hajdas;K. Arzner;M. Güdel;A. Zehnder
最近的一项研究使用RHESSI卫星作为康普顿偏振计，声称GRB 021206的瞬发辐射几乎是完全线性偏振的。这一点受到了随后的重新分析的挑战。我们提出了一种新的方法，将我们的方法应用于相同的数据。我们确定康普顿散射候选人仔细过滤事件的能量，时间和散射几何。我们的极化搜索基于垂直方向上的时间相关散射率，从而最佳地排除系统误差。我们进行模拟，以获得仪器的偏振灵敏度，这些模拟包括光子偏振。对于GRB 021206，我们正式找到了一个线性偏振度为100GRB = 41%，得出结论，数据质量是不足以约束在这种情况下的偏振度。我们进一步将我们的分析应用于GRB 030519 B，再次发现了零结果。
Using the RHESSI satellite as a Compton polarimeter, a recent study claimed that the prompt emission of GRB 021206 was almost fully linearly polarized. This was challenged by a subsequent reanalysis. We present a novel approach, applying our method to the same data. We identify Compton scattering candidates by carefully filtering events in energy, time, and scattering geometry. Our polarization search is based on time-dependent scattering rates in perpendicular directions, thus optimally excluding systematic errors. We perform simulations to obtain the instrument's polarimetric sensitivity, and these simulations include photon polarization. For GRB 021206, we formally find a linear polarization degree of ΠGRB = 41%, concluding that the data quality is insufficient to constrain the polarization degree in this case. We further applied our analysis to GRB 030519B and again found a null result.