论文标题
非常高的能量伽马射线爆发的无线电余星190829a和180720b
Radio Afterglows of Very High Energy Gamma-Ray Bursts 190829A and 180720B
论文作者
论文摘要
我们提出了长伽马射线爆发（GRB）190829a的高节奏多频射无线电观测，该观察是通过高能量立体镜面系统（H.E.S.S.）在100 GEV的光子能量下检测到的。使用Meer Karoo阵列望远镜（Meerkat，1.3 GHz）和高度的Microkelvin Imager的观察结果 - 大型阵列（Ami-La，15.5 GHz）开始了一天后的一天，并持续了近200天。我们使用了Swift X射线望远镜（XRT）的互补数据，该数据在爆炸后至100天。我们在爆炸后大约100天以上，发现了Meerkat和XRT的可能前向冲击组件。相反，AMI-LA光曲线似乎是由反向冲击发射支配的，直到燃烧后70天左右，当余气通量降至宿主星系水平以下。我们还提出了先前未发表的观察结果，对AMI-LA的其他H.E.S.S. S. S. S. S. S. S. S. S. S. S. GRB 180720b，这表明可能在不到10天内逐渐消失。我们介绍了三个GRB的无线电发射具有非常高的能量（VHE）伽玛射线发射和灵敏度有限的无线电余波样品之间的比较。 GRB 190829a的样品中任何GRB的各向同性无线电发光度最低，但是正如预期的那样，亮度的分布否则是一致的，而VHE GRB与其他与其他无线电发现的长长GRB相同的母体分布中得出。
We present high cadence multi-frequency radio observations of the long Gamma-Ray Burst (GRB) 190829A, which was detected at photon energies above 100 GeV by the High Energy Stereoscopic System (H.E.S.S.). Observations with the Meer Karoo Array Telescope (MeerKAT, 1.3 GHz), and Arcminute Microkelvin Imager - Large Array (AMI-LA, 15.5 GHz) began one day post-burst and lasted nearly 200 days. We used complementary data from Swift X-Ray Telescope (XRT), which ran to 100 days post-burst. We detected a likely forward shock component with both MeerKAT and XRT up to over 100 days post-burst. Conversely, the AMI-LA light curve appears to be dominated by reverse shock emission until around 70 days post-burst when the afterglow flux drops below the level of the host galaxy. We also present previously unpublished observations of the other H.E.S.S.-detected GRB, GRB 180720B from AMI-LA, which shows likely forward shock emission that fades in less than 10 days. We present a comparison between the radio emission from the three GRBs with detected very high energy (VHE) gamma-ray emission and a sensitivity-limited radio afterglow sample. GRB 190829A has the lowest isotropic radio luminosity of any GRB in our sample, but the distribution of luminosities is otherwise consistent, as expected, with the VHE GRBs being drawn from the same parent distribution as the other radio-detected long GRBs.
