论文标题
潮汐破碎作为1i/2017 U1的起源（'Oumuamua）
Tidal fragmentation as the origin of 1I/2017 U1 ('Oumuamua)
论文作者
论文摘要
The first discovered interstellar object (ISO), `Oumuamua (1I/2017 U1) shows a dry and rocky surface, an unusually elongated short-to-long axis ratio $c/a \lesssim 1/6$, a low velocity relative to the local standard of rest ($\sim 10$ km s$^{-1}$), non-gravitational accelerations, and tumbles on a few小时的时间尺度。推断的数量密度（$ \ sim 3.5 \ times 10^{13} -2 \ times 10^{15} $ PC $^{ - 3} $用于小行星ISOS的人群，由$ \ geq 10^3 $，相比之下，相比之下，$ \ geq 10^3 $，相比之下（$ \ libs）（$ \ siels becy ockim ockim ockim cockim ockim ockim cockim octers）。尽管某些场景可能会引起小行星ISO的弹出，但统一的形成理论尚未全面地联系所有“ Oumuamua的令人困惑的特征”并解释了人口。在这里，我们通过数值模拟表明，可以通过广泛的潮汐碎片化来进一步产生`oumuamua样的ISO，并在其挥发性丰富的母体与宿主星星的亲密接触中弹出。在植物座通道期间的密集加热增强了材料强度，使极其伸长的三轴ISO具有形状$ c/a \ sillesim 1/10 $，尺寸$ a \ sim 100 $ m和岩石表面。尽管升华温度低（例如CO）的挥发物同时耗尽，但在这些ISO中保留了H $ _2 $ o将其埋在表面下，提供了一个超出的源，而没有可测量的彗星活动，用于通过内部太阳能系统通过内部太阳能系统的非良好速度加速。我们推断，``oumuamua isos的祖细胞可能是来自泥石云，碎片磁盘的km大小的残留行星的长期长期彗星，或者在几个AU上的尸体，几个AU，几个AU，绕着低质量主流恒星或白色dwarfs绕的几个AU。这些提供了丰富的水库，以说明Oumuamua的发生率。
The first discovered interstellar object (ISO), `Oumuamua (1I/2017 U1) shows a dry and rocky surface, an unusually elongated short-to-long axis ratio $c/a \lesssim 1/6$, a low velocity relative to the local standard of rest ($\sim 10$ km s$^{-1}$), non-gravitational accelerations, and tumbles on a few hours timescale. The inferred number density ($\sim 3.5 \times 10^{13} - 2 \times 10^{15}$ pc$^{-3}$) for a population of asteroidal ISOs outnumbers cometary ISOs by $\geq 10^3$, in contrast to the much lower ratio ($\lesssim 10^{-2}$) of rocky/icy Kuiper belt objects. Although some scenarios can cause the ejection of asteroidal ISOs, a unified formation theory has yet to comprehensively link all `Oumuamua's puzzling characteristics and to account for the population. Here we show by numerical simulations that `Oumuamua-like ISOs can be prolifically produced through extensive tidal fragmentation and ejected during close encounters of their volatile-rich parent bodies with their host stars. Material strength enhanced by the intensive heating during periastron passages enables the emergence of extremely elongated triaxial ISOs with shape $c/a \lesssim 1/10$, sizes $a \sim 100$ m, and rocky surfaces. Although volatiles with low sublimation temperature (such as CO) are concurrently depleted, H$_2$O buried under surfaces is preserved in these ISOs, providing an outgassing source without measurable cometary activities for `Oumuamua's non-gravitational accelerations during its passage through the inner Solar System. We infer that the progenitors of `Oumuamua-like ISOs may be km-sized long-period comets from Oort clouds, km-sized residual planetesimals from debris disks, or planet-size bodies at a few AU, orbiting around low-mass main-sequence stars or white dwarfs. These provide abundant reservoirs to account for `Oumuamua's occurrence rate.
