脉冲星J2313+4253的周期性消零和奇偶调制特性的研究

Periodic nulling and even-odd modulation properties of PSR J2313+4253

脉冲星子脉冲的强度调制特征对揭示脉冲星辐射过程和磁层几何具有重要意义.前人研究表明,PSR J2313+4253的单脉冲序列具有44倍和2倍自转周期的强度调制.其中2倍周期的调制周期被称为奇偶性调制,其物理起源并不清晰.本文利用佳木斯66 m射电望远镜的观测数据,对脉冲星J2313+4253在2250 MHz的单脉冲辐射特性进行了详细研究.通过相位分离涨落谱(LRFS)、谐频分离的涨落谱(HRFS)和二维涨落谱(2DFS)的分析方法,发现PSR J2313+4253的奇偶性调制来自于其短周期子脉冲漂移,并且调制现象展现出了时间依赖性.分析表明,旋转木马模型下,奇偶性调制可能起源于脉冲星火花放电过程中,辐射区子辐射束间边界不清晰而发生的混叠效应.

Amplitude modulation of subpulses has substantial research implications for elucidating the geometric structure and emis-sion process of pulsars.Previous studies have revealed that the single-pulse sequence of PSR J2313+4253 exhibits am-plitude modulation with periodicities of 44 and 2 rotation periods.Moreover,shorter periodicity is associated with the even-odd modulation phenomenon,but its physical origin is unclear.We performed a detailed study of individual-pulse emission properties from the pulsar J2313+4253,observed at 2250 MHz using the Jiamusi 66 m radio telescope in this study.Using longitude-resolved,harmonic-resolved and two-dimensional fluctuation spectral techniques,we find that the even-odd modulation originates from short-period subpulse drifting,which exhibits considerable temporal dependence.The analysis reveals that the even-odd modulation phenomenon may be attributed to the aliasing effect caused by overlap-ping sub-beams within the radiation zone due to unclear boundaries during the sparking discharge process in the pulsar magnetosphere.