arXiv 1409.76412014-09-26astro-ph.EP

168 P/Hergenrother彗星爆发与碎裂事件的时间相关性

Temporal Correlation Between Outbursts and Fragmentation Events of Comet 168P/Hergenrother

Zdenek Sekanina

备注：: 24 pages, 12 tables, 3 figures; to appear in the International Comet Quarterly

摘要：

众所周知，爆发开始于一个突然出现和急剧变亮的“恒星核”-一个未解决的图像，一个从彗星表面出来的物质羽流和一个扩张的喷出物晕的初始阶段。由于这一特征的亮度与天体测量一起被大多数彗星观测者作为“核星等”定期报告，因此通过检查这些观测的时间表来确定核亮度的主要跳跃，可以直接确定爆发的开始时间，这是任何爆发的基本参数。虽然在没有首先仔细检查它们的兼容性的情况下，混合不同观测者的核震级是不允许的，但是从不同观测者报告的数据集获得的时间限制可以很容易地结合起来。这些集合的交集提供了对爆发开始时间的最严格的可能约束。在2012年168 P/Hergenrother彗星返回近日点期间，探测到三次爆发，并以良好到极好的精度确定了它们的时间。彗星经历的六次碎裂事件被证明是在爆发的同一时期发生的。在第一次爆发中，可能有三个伴星从主星脱离，在第二次爆发中有两个伴星，在最后一次爆发中有一个伴星。所有的同伴都是短命的，属于过于脆弱的碎片类。然而，结果表明，在第一次爆发中损失的大部分质量在升空过程中保持相对完整，而在最后一次爆发中情况正好相反。

英文摘要：

Outbursts are known to begin with a sudden appearance and steep brightening of a "stellar nucleus" --- an unresolved image of a plume of material on its way from the comet's surface and an initial stage of an expanding halo of ejecta. Since the brightness of this feature is routinely reported, together with astrometry, by most comet observers as the "nuclear magnitude," it is straightforward to determine the onset time, a fundamental parameter of any outburst, by inspecting the chronological lists of such observations for a major jump in the nuclear brightness. Although it is inadmissible to mix nuclear magnitudes by different observers without first carefully examining their compatibility, the time constraints obtained from data sets reported by different observers can readily be combined. The intersection of these sets provides the tightest possible constraint on the outburst's onset time. Applied to comet 168P/Hergenrother during its 2012 return to perihelion, three outbursts were detected and their timing determined with good to excellent accuracy. Six fragmentation events experienced by the comet are shown to have occurred in the same period of time as the outbursts. Three companions are likely to have broken off from the primary in the first outburst, two companions in the second outburst, and one companion in the last outburst. All companions were short-lived, belonging to the class of excessively brittle fragments. Yet, the results suggest that most of the mass lost in the first outburst remained relatively intact during the liftoff, while the opposite was the case in the last outburst.

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。

摘要：

英文摘要：

相关论文