论文标题
同时在爆发阶段快而更好的是FRB〜180301的视图
Simultaneous view of the FRB~180301 with FAST and NICER during a bursting phase
论文作者
论文摘要
FRB180301是最积极重复的快速无线电爆发（FRB），它显示了无线电爆发发射的极化角变化，这表明它们可能起源于高度磁性中子星的磁层中。我们使用快速射电望远镜和更好的X射线观测站进行了多波长运动，以调查与明亮的无线电爆发时间相吻合的任何可能的X射线发射。这些观察结果于3月4日，9日和19日发生。我们发现了五张明亮的无线电爆发，其中四个与更好的观察结果严格同时。收音机爆发的峰值通量密度在28-105美元之间，爆发通量在$ 27-170 $ MJY-MS之间，爆发持续时间在1.7-12.3美元的$ MS之间。 FRB〜180301的无线电爆发表现出复杂的时域结构，并且在单个爆发中检测到亚脉冲，没有明显的圆极化。与2019年的观测值相比，L波段的线性极化程度显着降低。在5ms，10ms，100ms，1sec和100秒的时间间隔内/周围，在无线电 - 伯斯特Barycenter校正的到达时间（$>5σ$置信度）上，我们没有检测到超过背景的任何X射线发射。 X射线上的$5σ$上限a）持续通量为$ <7.64 \ times 10^{ - 12} \，\ rm erg \，cm^{ - 2} \，s^{ - 1} $，等于$ l _ {\ rm x} <2.50 \ 2.50 s^{ - 1} $和b）5毫秒的通量为$ <2 \ times 10^{ - 11} \ rm erg \，cm^{ - 2} $，在无线电爆发区域。使用$ 5 $ MS X射线通量上限，我们可以估计无线电效率$η_{r/x} \ equiv l _ {\ rm Radio}/l _ {\ rm x-ray} \ gtrsim 10^{ - 8} $。 $η_{r/x} $上的派生上限与磁层模型和涉及相对论冲击的同步器maser模型一致。
FRB180301 is one of the most actively repeating fast radio bursts (FRBs) which has shown polarization angle changes in its radio burst emission, an indication for their likely origin in the magnetosphere of a highly-magnetized neutron star. We carried out a multi-wavelength campaign with the FAST radio telescope and NICER X-ray observatory to investigate any possible X-ray emission temporally coincident with the bright radio bursts. The observations took place on 2021 March 4, 9 and 19. We detected five bright radio bursts with FAST, four of which were strictly simultaneous with the NICER observations. The peak flux-density of the radio bursts ranged between $28-105$ mJy, the burst fluence between $27-170$ mJy-ms, and the burst durations between $1.7-12.3$ ms. The radio bursts from FRB~180301 exhibited complex time domain structure, and sub-pulses were detected in individual bursts, with no significant circular polarisation. The linear degree of polarisation in L-band reduced significantly compared to the 2019 observations. We do not detect any X-ray emission in excess of the background during the 5ms, 10ms, 100ms, 1sec and 100sec time intervals at/around the radio-burst barycenter-corrected arrival times, at a $>5σ$ confidence level. The $5σ$ upper limits on the X-ray a) persistent flux is $<7.64\times 10^{-12}\, \rm erg\, cm^{-2}\, s^{-1}$ , equivalent to $L_{\rm X}<2.50 \times 10^{45} \rm erg\, s^{-1}$ and b) 5 ms fluence is $<2\times 10^{-11} \rm erg\, cm^{-2}$, at the radio burst regions. Using the $5$ ms X-ray fluence upper limit, we can estimate the radio efficiency $η_{R/X} \equiv L_{\rm Radio}/L_{\rm X-ray} \gtrsim 10^{-8}$. The derived upper limit on $η_{R/X}$ is consistent with both magnetospheric models and synchrotron maser models involving relativistic shocks.
