论文标题
TOI-811b和Toi-852b：新的过境棕色矮人，质量相似，半径和年龄与苔丝任务截然不同
TOI-811b and TOI-852b: New transiting brown dwarfs with similar masses and very different radii and ages from the TESS mission
论文作者
论文摘要
我们报告了来自NASA的过境系外行星调查卫星任务的两个过渡性棕色矮人（BDS），TOI-811b和TOI-852B。这两个过境的BD具有相似的质量，但半径和年龄却非常不同。他们的寄主恒星具有相似的质量，有效的温度和金属性。年轻的和较大的过渡性BD是$ m_b = 55.3 \ pm 3.2 {\ rm m_j} $，$ r_b = 1.35 \ pm 0.09 {\ rm r_j} $的质量为$ m_b = 55.3 \ pm 3.2 {\ rm m_j} $，它是$ pm r_j} $，它的宿主星和$ p = 25.16551 \ pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm pm。它的年龄为$ 93^{+61} _ { - 29} $ MYR，我们从陀螺仪中的应用到其主机恒星的应用，这就是为什么该BD的半径相对较大，而不是从其宿主恒星中加热，因为该BD轨道比大多数已知的Transiting BD在更长的轨道时期。对TOI-811b青年的这种限制使我们能够测试BDS半径随着年龄的增长而迅速变化的近地质量 - 拉迪乌斯等线。 TOI-852B是一个年龄较大的（来自恒星等速线型号的4.0 Gyr）和较小的过渡性BD，质量为$ m_b = 53.7 \ pm 1.3 {\ rm m_j} $，半径为$ r_b = 0.75 0.00008 $天。 TOI-852B加入了其他旧的过境BD，它们会踪射最古老的底座质量 - 拉迪乌斯等线，其中BD半径的收缩渐近地减慢了。两位主机星的质量为$ m_ \ star = 1.32 {\ rm m_ \ odot} \ pm0.05 $，并且在其半径上有所不同，$ t _ {\ rm eff} $和[fe/h]，toi-811的$ 811具有$ r_ \ r_ \ r_ \ star = 1.27 \ pm0.09 \ pm0.09 \ pm0.09 \ pm09 { eff} = 6107 \ pm 77 $ k，和$ \ rm [fe/h] = +0.40 \ pm 0.09 $和TOI-852具有$ r_ \ star = 1.71 \ pm0.04 {\ r_ r_ \ odot} $ +0.33 \ pm 0.09 $。我们借此机会研究了如何分别作为年轻人和老年替代等速线的测试要点。
We report the discovery of two transiting brown dwarfs (BDs), TOI-811b and TOI-852b, from NASA's Transiting Exoplanet Survey Satellite mission. These two transiting BDs have similar masses, but very different radii and ages. Their host stars have similar masses, effective temperatures, and metallicities. The younger and larger transiting BD is TOI-811b at a mass of $M_b = 55.3 \pm 3.2{\rm M_J}$ and radius of $R_b = 1.35 \pm 0.09{\rm R_J}$ and it orbits its host star in a period of $P = 25.16551 \pm 0.00004$ days. Its age of $93^{+61}_{-29}$ Myr, which we derive from an application of gyrochronology to its host star, is why this BD's radius is relatively large, not heating from its host star since this BD orbits at a longer orbital period than most known transiting BDs. This constraint on the youth of TOI-811b allows us to test substellar mass-radius isochrones where the radius of BDs changes rapidly with age. TOI-852b is a much older (4.0 Gyr from stellar isochrone models of the host star) and smaller transiting BD at a mass of $M_b = 53.7 \pm 1.3{\rm M_J}$, a radius of $R_b = 0.75 \pm 0.03{\rm R_J}$, and an orbital period of $P = 4.94561 \pm 0.00008$ days. TOI-852b joins the likes of other old transiting BDs that trace out the oldest substellar mass-radius isochrones where contraction of the BD's radius asymptotically slows. Both host stars have a mass of $M_\star = 1.32{\rm M_\odot}\pm0.05$ and differ in their radii, $T_{\rm eff}$, and [Fe/H] with TOI-811 having $R_\star=1.27\pm0.09{\rm R_\odot}$, $T_{\rm eff} = 6107 \pm 77$K, and $\rm [Fe/H] = +0.40 \pm 0.09$ and TOI-852 having $R_\star=1.71\pm0.04{\rm R_\odot}$, $T_{\rm eff} = 5768 \pm 84$K, and $\rm [Fe/H] = +0.33 \pm 0.09$. We take this opportunity to examine how TOI-811b and TOI-852b serve as test points for young and old substellar isochrones, respectively.
