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arXiv 2402.14535astro-ph.EPphysics.ao-ph
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热木星大气中淬灭驱动的赤道耗竭与临边不对称性:以 WASP-96b 为例

Quenching-driven equatorial depletion and limb asymmetries in hot Jupiter atmospheres: WASP-96b example

Maria Zamyatina, Duncan A. Christie, Eric Hébrard, Nathan J. Mayne, Michael Radica, Jake Taylor, Harry Baskett, Ben Moore, Craig Lils, Denis Sergeev, Eva-Maria … 展开作者

Maria Zamyatina, Duncan A. Christie, Eric Hébrard, Nathan J. Mayne, Michael Radica, Jake Taylor, Harry Baskett, Ben Moore, Craig Lils, Denis Sergeev, Eva-Maria Ahrer, James Manners, Krisztian Kohary, Adina D. Feinstein

AI总结:

本文通过 WASP-96b 的三维 GCM 模拟,研究热木星大气中金属丰度增加如何移动淬灭层位置并导致 CH₄、NH₃ 和 HCN 赤道耗竭,进而利用晨昏临边不对称性区分不同化学状态的大气。

摘要:

热木星大气中由传输引起的淬灭是一个决定大气中处于化学平衡的部分与处于热化学(而非光热化学)非平衡的部分之间边界的过程。该边界的位置,即淬灭层,取决于大气中动力学时间尺度与化学时间尺度之间的相互作用,当这两个时间尺度相等时就会发生淬灭。我们利用热木星 WASP-96b 的无气溶胶三维 GCM 模拟,探讨了淬灭层位置对行星大气金属丰度增加的敏感性。我们发现,当金属丰度增加时,在约 $\sim$$10^{4}-10^{7}$ Pa 压强处出现的温度升高可能会使淬灭层的位置移动到由急流主导的压强区域,并导致 $CH_4$、$NH_3$ 和 $HCN$ 的赤道耗竭。我们讨论了这种耗竭如何影响行星的透射光谱,以及分析晨昏临边不对称性(尤其是在 $\sim3-5 μm$ 范围内)如何有助于区分处于化学平衡的不同金属丰度大气与上层处于热化学非平衡的大气。

英文摘要:

Transport-induced quenching in hot Jupiter atmospheres is a process that determines the boundary between the part of the atmosphere at chemical equilibrium and the part of the atmosphere at thermochemical (but not photothermochemical) disequilibrium. The location of this boundary, the quench level, depends on the interplay between the dynamical and chemical timescales in the atmosphere, with quenching occurring when these timescales are equal. We explore the sensitivity of the quench level position to an increase in the planet's atmospheric metallicity using aerosol-free 3D GCM simulations of a hot Jupiter WASP-96b. We find that the temperature increase at pressures of $\sim$$10^{4}-10^{7}$ Pa that occurs when metallicity is increased could shift the position of the quench level to pressures dominated by the jet, and cause an equatorial depletion of $CH_4$, $NH_3$ and $HCN$. We discuss how such a depletion affects the planet's transmission spectrum, and how the analysis of the evening-morning limb asymmetries, especially within $\sim3-5 μm$, could help distinguish atmospheres of different metallicities that are at chemical equilibrium from those with the upper layers at thermochemical disequilibrium.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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