PSR J1420−6048 is a young γ-ray pulsar with recurrent glitches. Utilizing long-term monitoring data obtained from the Fermi Gamma-ray Space Telescope, we found that PSR J1420−6048 has shown γ-ray flux variation and we also detected four glitches between 2008 and 2019. Two of the glitches are previously unknown, and their γ-ray spectrum also shows variability between each glitch. Because the results might be contaminated by background sources, we discuss whether the observed changes in flux and spectra were caused by artificial misallocations of photons from a nearby pulsar wind nebula (HESS J1420−607) and a pulsar (PSR J1418−6058), or by a change of the emission geometry from the target pulsar itself. We examine the correlation of the flux changes and the alternating pulse structure to investigate whether the emission geometry in the outer magnetosphere was changing. By assuming that the observational features did not totally result from the background environment, we compare our results with similar phenomena observed in other γ-ray pulsars. We propose that a strong crust crack can cause timing anomaly of a neutron star, which can affect the particle accelerations or pair creation regions, resulting in the changes of emission behaviours.

中文翻译：

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PSR J1420-6048 γ射线变异性和毛刺的研究

PSR J1420−6048 是一颗年轻的 γ 射线脉冲星，具有反复出现的毛刺。利用从费米伽马射线太空望远镜获得的长期监测数据，我们发现 PSR J1420−6048 显示出 γ 射线通量变化，我们还检测到 2008 年至 2019 年之间的四个毛刺。其中两个毛刺以前是未知的，并且他们的 γ 射线光谱还显示了每个故障之间的可变性。因为结果可能受到背景源的污染，我们讨论观察到的通量和光谱变化是否是由附近脉冲星风星云 (HESS J1420-607) 和脉冲星 (PSR J1418-6058) 的光子的人工错误分配引起的，或者通过改变目标脉冲星本身的发射几何形状。我们检查了通量变化和交替脉冲结构的相关性，以研究外磁层中的发射几何形状是否正在发生变化。通过假设观测特征并非完全来自背景环境，我们将我们的结果与在其他 γ 射线脉冲星中观察到的类似现象进行了比较。我们提出强烈的地壳裂缝会导致中子星的计时异常，这会影响粒子加速度或对产生区域，从而导致发射行为的变化。