arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2408.06231astro-ph.SRastro-ph.EP
收藏

环双星行星 Delorme 1 (AB)b 的潜在起源

On the potential origin of the circumbinary planet Delorme 1 (AB)b

Matthew Teasdale, Dimitris Stamatellos

阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

AI总结：

本文通过三种形成情景模拟环双星行星 Delorme 1 (AB)b 的起源，发现各模型只能部分解释其轨道间距、质量和吸积率，揭示现有形成理论面临挑战。

摘要：

近年来已发现许多环双星气态巨行星。宽轨道上环双星行星的形成机制尚不清楚。我们研究了 Delorme 1 (AB)b 的形成，这是一颗质量为 13±5M_J 的行星，在 84AU 处绕其宿主双星运行。该行星仍在吸积，而其估计年龄为 40Myr，这是出乎意料的，因为原行星盘的耗散本应使这一过程停止。利用平滑粒子流体动力学代码 SEREN，我们模拟了该行星的三种形成情景。在情景 I 中，行星在一个大质量盘（通过引力不稳定性）中的宽轨道上原位形成；在情景 II 中，行星在一个大质量盘中更靠近双星处形成（通过引力不稳定性）；在情景 III 中，行星在一个质量较小的盘中更靠近双星处形成（通过核心吸积）。情景 I 中的行星停留在观测到的间距处，其质量吸积率与观测值一致，但其最终质量过高。在情景 II 中，行星通过向外迁移或双星散射到达观测到的间距，其质量吸积率与观测值相当；然而，行星质量高于观测值。在情景 III 中，行星的最终质量和质量吸积率与观测值相当，但行星的间距较小。我们得出结论，所有模型可能都能解释观测的某些特征，但不能解释全部特征，这引发了关于气体如何从环行星盘吸积到行星上以及该系统假定年龄的问题。

英文摘要：

Many circumbinary gas giant planets have been recently discovered. The formation mechanism of circumbinary planets on wide orbits is unclear. We investigate the formation of Delorme 1 (AB)b, a 13$\pm$5M$_{\rm J}$ planet, orbiting its host binary at 84AU. The planet is accreting while having an estimated age of 40Myr, which is unexpected, as this process should have ceased due to the dissipation of the protoplanetary disc. Using the Smoothed Particle Hydrodynamics code SEREN, we model three formation scenarios for this planet. In Scenario I the planet forms in-situ on a wide orbit in a massive disc (by gravitational instability), in Scenario II closer to the binary in a massive disc (by gravitational instability), and in Scenario III much closer to the binary in a less massive disc (by core accretion). Planets in Scenario I stay at the observed separation, have mass accretion rates consistent with observed value, but their final mass is too high. In Scenario II, the planet reaches the observed separation through outward migration or scattering by the binary, and has mass accretion rate comparable to the observed; however, the planet mass is above the observed value. In Scenario III, the planet's final mass and mass accretion rate are comparable to the observed ones but the planet's separation is smaller. We conclude that all models may explain some features of the observations but not all of them, raising questions about how gas is accreted onto the planet from its circumplanetary disc, and of the presumed age of the system.

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。

↑