论文标题
Oort Cloud Ecology II：超极的OORT云和小行星闯入者的起源
Oort cloud Ecology II: Extra-solar Oort clouds and the origin of asteroidal interlopers
论文作者
论文摘要
我们模拟了在200个最近的恒星（根据Gaia DR2）数据库附近的Oort云的形成和演变。这项研究是通过数字整合围绕父恒星和银河电位的轨道上的行星和次要物体来进行的。计算从1 \，Gyr开始，并继续前进100Myr。在这个时间范围内，我们模拟了小行星（和行星）如何从恒星附近弹出并定居在Oort云中，以及它们如何逃脱局部恒星重力以形成潮汐蒸汽。小行星的0.0098至0.026的比例保持与他们的母恒星的结合。由于银河潮汐场的影响，这些小行星的轨道各向同性和循环构造最终在10^4和2 10^5au之间形成oort云。我们估计附近有6％的恒星可能在其卵子云中有一个行星。大多数小行星（和某些行星）与母体恒星无界，以在银河电位上自由漂浮。这些孤圈在银河系中心与宿主恒星相似的轨道上，形成了茂密的流氓星际小行星和行星。 太阳系偶尔会通过这样的潮汐流，有可能引起该流中与对象的偶尔接触。最近发现的两个对象，1i/（2017 Q3）'Oumuamua和2i/（2019 Q4）Borisov，可能是这样的对象。尽管单独的Lapis起源的方向不能轻易地追溯到原始主机，但来自同一来源的多个此类对象可能有助于识别其起源。目前，太阳系处于附近10颗恒星的潮汐流的弓形或尾流，这可能会对相互作用速率产生重大贡献。 （简略）
We simulate the formation and evolution of Oort clouds around the 200 nearest stars (within 16pc according to the Gaia DR2) database. This study is performed by numerically integrating the planets and minor bodies in orbit around the parent star and in the Galactic potential. The calculations start 1\,Gyr ago and continue for 100Myr into the future. In this time frame, we simulate how asteroids (and planets) are ejected from the star's vicinity and settle in an Oort cloud and how they escape the local stellar gravity to form tidal steams. A fraction of 0.0098 to 0.026 of the asteroids remain bound to their parent star. The orbits of these asteroids isotropizes and circularizes due to the influence of the Galactic tidal field to eventually form an Oort cloud between 10^4 and 2 10^5au. We estimate that 6% of the nearby stars may have a planet in its Oort cloud. The majority of asteroids (and some of the planets) become unbound from the parent star to become free floating in the Galactic potential. These soli lapides remain in a similar orbit around the Galactic center as their host star, forming dense streams of rogue interstellar asteroids and planets. The Solar system occasionally passes through such tidal streams, potentially giving rise to occasional close encounters with object in this stream. The two recently discovered objects, 1I/(2017 Q3) 'Oumuamua and 2I/(2019 Q4) Borisov, may be such objects. Although the direction from which an individual solus lapis originated cannot easily be traced back to the original host, multiple such objects coming from the same source might help to identify their origin. At the moment the Solar system is in the bow or wake of the tidal stream of 10 of the nearby stars which might contribute considerably to the interaction rate. (abridged)
