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arXiv 1707.05046astro-ph.HE
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双漂移子脉冲现象的起源

On the origin of the bi-drifting subpulse phenomenon in pulsars

Andrzej Szary, Joeri van Leeuwen

摘要:

PSR J 0815 +0939报告的独特和极不寻常的漂移特征,其中一个组件的子脉冲漂移的方向与一般趋势相反,是对脉冲星理论的真正挑战。在本文中,我们观测量化的漂移方向在其整个配置文件,并发现,第二个组件是唯一一个表现出“双漂移”,这意味着只有第二个组件的方向相反的其他移动。我们在这里提出了一个模型,表明所观察到的双漂移现象如下的洞察力,放电区域,即火花,不旋转的磁轴本身,而是围绕点的电势极值在极冠:最小的脉冲星的情况下($\mathbfΩ \cdot \mathbf{B} < 0$)和最大的反脉冲星的情况下($\mathbfΩ \cdot \mathbf{B} > 0$)。我们表明,一个纯粹的偶极表面磁场不能表现出双漂移行为,但某些非偶极配置可以。我们可以区分两种类型的解决方案,相对较低($\sim 10^{12} \,{\rm G}$)和高($\sim 10^{14} \,{\rm G}$)表面磁场。取决于表面磁场的强度,磁场线的曲率半径的范围从$10^{5} \,{\rm cm}$到$10^{7}\,{\rm cm}$。脉冲星\J ~使我们能够获得的内部加速区域的等离子体生成过程中必不可少的极冠条件的理解,通过连接所观察到的子脉冲移位的基础火花运动。

英文摘要:

The unique and highly unusual drift feature reported for PSR J0815+0939, wherein one component's subpulses drift in the direction opposite of the general trend, is a veritable challenge to pulsar theory. In this paper, we observationally quantify the drift direction throughout its profile, and find that the second component is the only one that exhibits "bi-drifting", meaning that only second component moves in the direction opposite of the others. We here present a model that shows that the observed bi-drifting phenomenon follows from the insight that the discharging regions, i.e. sparks, do not rotate around the magnetic axis per se, but rather around the point of electric potential extremum at the polar cap: minimum in the pulsar case ($\mathbfΩ \cdot \mathbf{B} < 0$) and maximum in the antipulsar case ($\mathbfΩ \cdot \mathbf{B} > 0$). We show that a purely dipolar surface magnetic field cannot exhibit bi-drifting behaviour, though certain non-dipolar configurations can. We can distinguish two types of solutions, with relatively low ($\sim 10^{12} \,{\rm G}$) and high ($\sim 10^{14} \,{\rm G}$) surface magnetic fields. Depending on the strength of the surface magnetic field, the radius of the curvature of magnetic field lines ranges from $10^{5} \,{\rm cm}$ to $10^{7}\,{\rm cm}$. Pulsar \J~allows us to gain an understanding of the polar-cap conditions essential for plasma generation processes in the inner acceleration region, by linking the observed subpulse shift to the underlying spark motion.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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