REVISITING JOVIAN-RESONANCE INDUCED CHONDRULE FORMATION
REVISITING JOVIAN-RESONANCE INDUCED CHONDRULE FORMATION
复制标题
重新审视木星共振引起的球粒形成
DOI：
10.1088/2041-8205/794/1/l7
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
and T. Yamamoto
中科院分区：
文献类型：
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作者：
M. Nagasawa ;K. K. Tanaka;H. Tanaka;T. Nakamoto;H. Miura;and T. Yamamoto
有人提出，被木星平均运动共振扰动的行星体是形成球粒的激波的来源。认为这种激波诱导球粒的形成要求小行星相对于气盘的速度在1AU时约为≳7公里S−1的量级。在以往的行星小激发研究中，研究了木星平均运动共振和气体阻力的影响，但在小行星带内得到的速度至多为S−1 8公里，这不足以解释球粒陨石的普遍存在。在这篇文章中，我们重新检查了木星共振的影响，并考虑了小行星带中由气盘引力引起的长期共振。我们发现几百公里大小的小行星相对于气盘的速度超过了12公里的S−1，并且这是在3：1平均运动共振附近实现的。加热区被限制在1.5AU到3.5AU之间的相对较窄的频段内。我们的结果表明，在木星形成后，小行星区域有效地产生了球粒陨石。我们还发现，许多行星体散布在海王星以外的地方。我们的发现可以解释彗星中结晶硅酸盐的存在，如果分散的行星体包括经过冲击加热处理的硅酸盐尘埃。
It is proposed that planetesimals perturbed by Jovian mean-motion resonances are the source of shock waves that form chondrules. It is considered that this shock-induced chondrule formation requires the velocity of the planetesimal relative to the gas disk to be on the order of≳ 7 km s− 1 at 1 AU. In previous studies on planetesimal excitation, the effects of Jovian mean-motion resonance together with the gas drag were investigated, but the velocities obtained were at most 8 km s− 1 in the asteroid belt, which is insufficient to account for the ubiquitous existence of chondrules. In this paper, we reexamine the effect of Jovian resonances and take into account the secular resonance in the asteroid belt caused by the gravity of the gas disk. We find that the velocities relative to the gas disk of planetesimals a few hundred kilometers in size exceed 12 km s− 1, and that this is achieved around the 3: 1 mean-motion resonance. The heating region is restricted to a relatively narrowband between 1.5 AU and 3.5 AU. Our results suggest that chondrules were produced effectively in the asteroid region after Jovian formation. We also find that many planetesimals are scattered far beyond Neptune. Our findings can explain the presence of crystalline silicate in comets if the scattered planetesimals include silicate dust processed by shock heating.