EXPLOSIVE OUTFLOWS POWERED BY THE DECAY OF NON-HIERARCHICAL MULTIPLE SYSTEMS OF MASSIVE STARS: ORION BN/KL
EXPLOSIVE OUTFLOWS POWERED BY THE DECAY OF NON-HIERARCHICAL MULTIPLE SYSTEMS OF MASSIVE STARS: ORION BN/KL
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DOI：
10.1088/0004-637x/727/2/113
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发表时间：
2010-11
期刊：
影响因子：
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通讯作者：
J. Bally;N. Cunningham;N. Moeckel;M. Burton;N. Smith;A. Frank;Å. Nordlund
中科院分区：
文献类型：
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作者：
J. Bally;N. Cunningham;N. Moeckel;M. Burton;N. Smith;A. Frank;Å. Nordlund
猎户座星云后面的OMC1爆发的Becklin-Neugebauer (BN)/ Kleinman-Low （KL）外流可能是由500年前一个非分层多系统的动态衰变驱动的，该系统以大约10-30 km s−1的速度喷出了大质量恒星I、BN和源n。新的对H2特征的自运动测量表明，在测量误差范围内，流出物起源于恒星抛射的位置。结合已发表的数据，这些测量表明流出的年龄为~ 500年，与恒星喷射以来的时间相似。喷出恒星和流出恒星的总动能约为2至6 × 1047尔格。有人提出，短周期双星（最有可能是源1）形成时释放的引力势能导致了恒星抛射，并为流出提供了动力。提出了一个紧凑的、无层次的多星系统的形成，它的衰变为一个被抛出的双星和两个高速恒星，以及流出的发射。有三种机制可能促成了气体中的爆炸：(1)恒星抛射后星团周围包膜的解除，(2)在最后的恒星相遇期间，星周盘的破坏和由此产生的碎片的高速排出，以及(3)储存的磁能的释放。似是而非的原恒星盘端包络特性可以产生观测到的流出质量、速度和动能分布。被抛出的恒星可能通过后退或邦迪-霍伊尔吸积获得了新的圆盘，其轴与它们的速度大致正交。OMC1的气体和恒星的排出可能是由恒星相互作用驱动的。
The explosive Becklin–Neugebauer (BN)/Kleinman–Low (KL) outflow emerging from OMC1 behind the Orion Nebula may have been powered by the dynamical decay of a non-hierarchical multiple system ∼500 years ago that ejected the massive stars I, BN, and source n, with velocities of about 10–30 km s−1. New proper-motion measurements of H2 features show that within the errors of measurement, the outflow originated from the site of stellar ejection. Combined with published data, these measurements indicate an outflow age of ∼500 years, similar to the time since stellar ejection. The total kinetic energy of the ejected stars and the outflow is about 2 to 6 × 1047 erg. It is proposed that the gravitational potential energy released by the formation of a short-period binary, most likely source I, resulted in stellar ejection and powered the outflow. A scenario is presented for the formation of a compact, non-hierarchical multiple star system, its decay into an ejected binary and two high-velocity stars, and launch of the outflow. Three mechanisms may have contributed to the explosion in the gas: (1) unbinding of the circumcluster envelope following stellar ejection, (2) disruption of circumstellar disks and high-speed expulsion of the resulting debris during the final stellar encounter, and (3) the release of stored magnetic energy. Plausible protostellar disk end envelope properties can produce the observed outflow mass, velocity, and kinetic energy distributions. The ejected stars may have acquired new disks by fall-back or Bondi–Hoyle accretion with axes roughly orthogonal to their velocities. The expulsion of gas and stars from OMC1 may have been driven by stellar interactions.