论文标题
一个快速的无线电爆发祖细胞出生于银河系合并
A fast radio burst progenitor born in a galaxy merger
论文作者
论文摘要
我们报告了一项巨大的Metrewave射电望远镜HI 21cm映射研究，对快速无线电爆发（FRB）FRB20180916b的中性原子氢（HI）的中性原子氢（HI）$ z \ of $ z \约0.03399 $。我们发现，FRB主机的HI质量为$ \ rm m_ {hi} =（2.74 \ pm 0.33）\ times 10^9 \ m_ \ odot $和高的HI与恒星质量比，$ \ $ \ $ \ of 1.3 $。因此，FRB宿主是一种气体丰富但近乎弥补的星系，在最近的过去很可能获得了大量的HI。 HI分布受到干扰，在东北尾尾中检测到延长的HI 21cm发射，向南尾巴，银河中心和FRB位置之间的HI孔，以及接近FRB位置的高HI柱密度。 FRB主机是一个小组的一部分，在其HI 21厘米发射中检测到四个同伴，其最接近的是来自FRB位置的22〜kpc。气体富度和干扰的HI分布表明，FRB宿主最近进行了一次次要合并，该合并增加了HI质量，干扰了Galaxy磁盘中的HI，并将HI在FRB位置附近压缩以增加其表面密度。我们建议这次合并导致了银河郊区的恒星形成爆发，这引起了FRB祖先。次要合并的证据与FRB祖细胞是巨大的恒星，由于合并事件而形成的场景一致。
We report a Giant Metrewave Radio Telescope HI 21cm mapping study of the neutral atomic hydrogen (HI) in the host galaxy of the fast radio burst (FRB) FRB20180916B at $z \approx 0.03399$. We find that the FRB host has an HI mass of $\rm M_{HI} = (2.74 \pm 0.33) \times 10^9 \ M_\odot$ and a high HI-to-stellar mass ratio, $\approx 1.3$. The FRB host is thus a gas-rich but near-quiescent galaxy, that is likely to have acquired a significant mass of HI in the recent past. The HI distribution is disturbed, with extended HI 21cm emission detected in a north-eastern tail, a counter-tail towards the south, an HI hole between the galaxy centre and the FRB location, and a high HI column density measured close to the FRB position. The FRB host is part of a group with four companions detected in their HI 21cm emission, the nearest of which is only 22~kpc from the FRB location. The gas-richness and disturbed HI distribution indicate that the FRB host has recently undergone a minor merger, which increased its HI mass, disturbed the HI in the galaxy disk, and compressed the HI near the FRB location to increase its surface density. We propose that this merger caused the burst of star-formation in the outskirts of the galaxy that gave rise to the FRB progenitor. The evidence for a minor merger is consistent with scenarios in which the FRB progenitor is a massive star, formed due to the merger event.
