论文标题
迁移热木星的通货膨胀
Inflation of Migrated Hot Jupiters
论文作者
论文摘要
当一小部分表面辐射沉积在内部深处时，可以在模型中模拟观察到的具有高平衡温度的气体巨型行星的低密度。同时，迁移理论表明，热木星远离其宿主明星并向内迁移。我们将磁盘迁移纳入对热木星不断发展的内部的模拟中，以确定迁移是否对行星的通胀有持久影响。我们量化了迁移行星的半径与作为半径差异形成的行星半径之间的差异。我们对内部加热背后的物理机制仍然不可知，但假设它会以一定的比例缩放。我们发现，在行星迁移时，从宿主明星收到的辐射的变化会影响地球的通货膨胀和最终半径。沉积在内部（> 5％）中的能量较高的模型显示，当沉积物的压力高于p = 1 bar时，半径差异很大。对于较小的1％分数，对于任何沉积深度，都没有半径差异。我们表明，统一的加热机制可能会导致不同的通货膨胀率，具体取决于迁移历史。如果即将对天然气巨头平均密度和气氛的观察结果更好地表明潜在的加热机制，这可能有助于限制此类行星的先前迁移。
The observed low densities of gas giant planets with a high equilibrium temperature can be simulated in models when a fraction of the surface radiation is deposited deeper in the interior. Meanwhile migration theories suggest that hot Jupiters formed further away from their host-star and migrated inward. We incorporate disk migration in simulations of the evolving interior of hot Jupiters to determine whether migration has a long lasting effect on the inflation of planets. We quantify the difference between the radius of a migrated planet and the radius of a planet that formed in situ as the radius discrepancy. We remain agnostic about the physical mechanism behind interior heating, but assume it scales with the received stellar flux by a certain fraction. We find that the change in irradiation received from the host-star while the planet is migrating can affect the inflation and final radius of the planet. Models with a high fraction of energy deposited in the interior ( > 5%) show a significant radius discrepancy when the deposit is at higher pressures than P=1 bar. For a smaller fraction of 1%, there is no radius discrepancy for any deposit depth. We show that a uniform heating mechanism can cause different rates of inflation, depending on the migration history. If the forthcoming observations on mean densities and atmospheres of gas giants give a better indication of a potential heating mechanism, this could help to constrain the prior migration of such planets.
