论文标题
岩石行星的内部结构和磁矩。应用于苔丝发现的第一个系外行星
Internal Structure and Magnetic Moment of Rocky Planets. Application to the first exoplanets discovered by TESS
论文作者
论文摘要
为了使行星在其表面上被认为是可居住的，它的磁场是保护其大气免受恒星风能和宇宙射线的重要优势。潜在可居住行星的磁保护在确定检测大气生物签名的机会方面起着关键作用。本文建议将初步参考地球模型（PREM）内部结构作为数值模型的基础。使用该模型，我们估计了干燥和水丰富的地球和超级地球的磁性。我们将其应用于苔丝确认的第一个176个行星上的这种行星。使用PREM作为参考，我们估计干燥和水丰富的岩石行星的内部结构。该模型估计了行星的平均密度和核心大小，并根据其磁力力矩取决于它是否被潮汐锁定。我们的模型估计热力学变量是压力的函数，并包括盐水作为水富外甲壳的组成部分。我们尚未使用完美的层分化近似。我们已经用具有相似特征的太阳系中的那些行星和卫星验证了我们的模型。内部结构特征，质量，平均密度，惯性因子和局部rossby数字中观察到的值的差异非常低甚至可以忽略不计。估计的磁矩也与观察到的磁矩非常相似。我们已经将模型应用于苔丝确认的第一个176个行星，发现从天文学的角度来看，TOI-700 D和TOI-2257 B是最有趣的，是位于可居住区（HZ）的最有趣的行星，尽管它们的磁矩仅是地球磁矩的0.01。
For a planet to be considered habitable on its surface, it is an important advantage for it to have a magnetic field that protects its atmosphere from stellar winds as well as cosmic rays. Magnetic protection of potentially habitable planets plays a key role in determining the chances of detecting atmospheric biosignatures. This paper proposes to use the Preliminary Reference Earth Model (PREM) internal structure as the base of a numerical model. With this model, we estimate the magnetic properties of dry and water-rich Earth-like and Super-Earth-like planets. We apply it to those of this kind at the first 176 planets confirmed by TESS. Using PREM as a reference, we estimate the internal structure of dry and water-rich rocky planets. This model provides an estimation of the average density and core size of the planet and, with them, its magnetic moment depending on whether it is tidally locked or not. Our model estimates the thermodynamic variables as a function of pressure and includes saltwater as a component of water-rich exoplanets. We have not used the perfect layer differentiation approximation. We have validated our model with those planets and satellites in the Solar system with similar characteristics. The differences with the observed values in the internal structure characteristics, mass, average density, moment of inertia factor, and local Rossby number are remarkably low or even negligible. The estimated magnetic moments are also very similar to the observed ones. We have applied the model to the first 176 planets confirmed by the TESS, finding that, from an astrobiological perspective TOI-700 d and TOI-2257 b are the most interesting ones as being located in the habitable zone (HZ), although their magnetic moments are only about 0.01 of the Earth's magnetic moment.
