标题： PSR J1452-6036脉冲星跃变后的宽频辐射变化约束 显示英文标题

标题： Constraints on wide-band radiative changes after a glitch in PSR J1452-6036

摘要： 我们展示了年轻至中年射电脉冲星J1452-6036的高灵敏度宽频带（704到4032 MHz）观测结果，这些观测是在一次 glitch 发生前的多个时间点以及意外地在 glitch 发生后不久进行的。这次 glitch 发生的时间是2019年4月27日。 我们使用Parkes射电望远镜上的新型超宽带低频（UWL）接收器获取了数据，并使用马尔可夫链蒙特卡洛技术稳健地估计了 glitch 参数。 我们第三次观测会话的数据开始于最佳拟合 glitch 时刻后约3小时，我们将其限制在4分钟以内。 该 glitch 的规模适中，自旋频率的相对变化为$270.52(3) \times 10^{-9}$。 我们没有测量到显著的减速率变化，也没有发现快速衰减的 glitch 成分的证据。 我们系统性地研究了 glitch 是否影响了脉冲星的任何辐射参数，发现其谱指数、谱形状、偏振分数和旋转量在 glitch 时期内的不确定性范围内保持恒定。 然而，在 glitch 后的时期内，其脉冲平均通量密度显著增加了约10%，并在我们的第四次观测（一天后）之前略有下降。 我们表明，这种增加不太可能是由校准问题引起的。 虽然我们不能排除它是由于折射星际闪烁造成的，但它很难与折射效应相吻合。 通量密度增加与 glitch 事件的巧合概率较低。 最后，我们展示了脉冲星脉冲轮廓在整个频带中的演化。 其极化脉冲轮廓的形态在精度优于2%的情况下保持不变。 显示英文摘要

摘要： We present high-sensitivity, wide-band observations (704 to 4032 MHz) of the young to middle-aged radio pulsar J1452-6036, taken at multiple epochs before and, serendipitously, shortly after a glitch occurred on 2019 April 27. We obtained the data using the new ultra-wide-bandwidth low-frequency (UWL) receiver at the Parkes radio telescope, and we used Markov Chain Monte Carlo techniques to estimate the glitch parameters robustly. The data from our third observing session began 3 h after the best-fitting glitch epoch, which we constrained to within 4 min. The glitch was of intermediate size, with a fractional change in spin frequency of $270.52(3) \times 10^{-9}$. We measured no significant change in spin-down rate and found no evidence for rapidly-decaying glitch components. We systematically investigated whether the glitch affected any radiative parameters of the pulsar and found that its spectral index, spectral shape, polarisation fractions, and rotation measure stayed constant within the uncertainties across the glitch epoch. However, its pulse-averaged flux density increased significantly by about 10 per cent in the post-glitch epoch and decayed slightly before our fourth observation a day later. We show that the increase was unlikely caused by calibration issues. While we cannot exclude that it was due to refractive interstellar scintillation, it is hard to reconcile with refractive effects. The chance coincidence probability of the flux density increase and the glitch event is low. Finally, we present the evolution of the pulsar's pulse profile across the band. The morphology of its polarimetric pulse profile stayed unaffected to a precision of better than 2 per cent.