FROM PLANETESIMALS TO DUST: LOW-GRAVITY EXPERIMENTS ON RECYCLING SOLIDS AT THE INNER EDGES OF PROTOPLANETARY DISKS
FROM PLANETESIMALS TO DUST: LOW-GRAVITY EXPERIMENTS ON RECYCLING SOLIDS AT THE INNER EDGES OF PROTOPLANETARY DISKS
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从星子到尘埃：原行星盘内缘固体回收的低重力实验
DOI：
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
T. Jankowski
中科院分区：
文献类型：
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作者：
C. de Beule;T. Kelling;G. Wurm;J. Teiser;T. Jankowski
不同大小的固体的输送是原行星盘演化和行星形成的一个重要过程。大的固体被认为是向内漂移的;在彗星中发现的高温矿物被认为是向外迁移的。从抛物线飞行的低重力实验，我们研究了由固态温室效应和尘埃床上层内的电泳引起的尘埃体的光致侵蚀。研究的重力水平分别为0.16 g、0.38 g、1 g和1.7 g。实验期间的光通量为12 ± 2 kW m−2，环境压力为6 ± 0.9 mbar。光致侵蚀是强烈的重力依赖性，这是与发达国家的模型。特别是对于小的尘埃体（（次）-星子），在原行星盘的光学薄的内边缘有效的侵蚀是可能的。光致侵蚀可以防止较大天体的重要部分过于靠近宿主星星，从而被吸积。产生的小尘埃继续受到电泳作用，并部分向上和向外输送到磁盘表面;在磁盘的寿命期间观察到产生的小尘埃颗粒。侵蚀尘埃的部分参与了随后的周期的增长在星子形成。另一部分尘埃可能会被行星大小的天体收集，如果这个天体已经靠近盘边缘。无论哪种方式，光诱导侵蚀都是原行星盘中有效的循环过程。
Transporting solids of different sizes is an essential process in the evolution of protoplanetary disks and planet formation. Large solids are supposed to drift inward; high-temperature minerals found in comets are assumed to have been transported outward. From low-gravity experiments on parabolic flights, we studied the light-induced erosion of dusty bodies caused by a solid-state greenhouse effect and photophoresis within a dust bed's upper layers. The gravity levels studied were 0.16g, 0.38g, 1g, and 1.7g. The light flux during the experiments was 12 ± 2 kW m−2 and the ambient pressure was 6 ± 0.9 mbar. Light-induced erosion is strongly gravity dependent, which is in agreement with a developed model. In particular for small dusty bodies ((sub)-planetesimals), efficient erosion is possible at the optically thin inner edges of protoplanetary disks. Light-induced erosion prevents significant parts of a larger body from moving too close to the host star and being subsequently accreted. The small dust produced continues to be subject to photophoresis and is partially transported upward and outward over the surface of the disk; the resulting small dust particles are observed over the disk's lifetime. The fraction of eroded dust participates in subsequent cycles of growth during planetesimal formation. Another fraction of dust might be collected by a body of planetary size if this body is already present close to the disk edge. Either way, light-induced erosion is an efficient recycling process in protoplanetary disks.
DOI：
10.1088/0004-637x/783/2/111
发表时间：
2014
期刊：
The Astrophysical Journal
影响因子：
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作者：
T. Kelling;G. Wurm;M. Köster
通讯作者：
M. Köster