论文标题
在与“恒星字符串” Theia 301相关的年轻三重系统中，Kelt-Tess黯然失色的二进制
A KELT-TESS Eclipsing Binary in a Young Triple System Associated with a "Stellar String" Theia 301
论文作者
论文摘要
HD 54236是附近的，广泛的公共动物视觉对，以前已被鉴定为由于强大的X射线发射和锂吸收而很可能很年轻。在这里，我们报告发现，宽对〜54236a的更明亮的成员本身就是一种黯然失色的二进制（EB），其中包括2.4 d轨道上的两个近似太阳质量的星星。它代表了一个潜在的宝贵机会，可以扩大年轻恒星年龄的基准级EBS数量。使用新的K-dwarf伴侣中CA2H＆K发射和锂吸收的新观察结果，HD 54236B，我们获得了系统的225 +/- 50 MYR的稳健年龄估计值。这个年龄估计和GAIA适当的动作表明HD 54236与Theia〜301（新发现的本地“恒星字符串”）相关联，本身可能与AB DOR移动组通过共享的恒星成员有关。将此年龄估计用于AB〜DOR本身减轻了观察和理论之间的张力，这些张力是在使用年轻年龄估计的情况下为90M_JUP星/棕色矮人AB DOR C所产生的。
HD 54236 is a nearby, wide common-proper-motion visual pair that has been previously identified as likely being very young by virtue of strong X-ray emission and lithium absorption. Here we report the discovery that the brighter member of the wide pair, HD~54236A, is itself an eclipsing binary (EB), comprising two near-equal solar-mass stars on a 2.4 d orbit. It represents a potentially valuable opportunity to expand the number of benchmark-grade EBs at young stellar ages. Using new observations of Ca2H&K emission and lithium absorption in the wide K-dwarf companion, HD 54236B, we obtain a robust age estimate of 225 +/- 50 Myr for the system. This age estimate and Gaia proper motions show HD 54236 is associated with Theia~301, a newly discovered local "stellar string", which itself may be related to the AB Dor moving group through shared stellar members. Applying this age estimate to AB~Dor itself alleviates reported tension between observation and theory that arises for the luminosity of the 90M_Jup star/brown dwarf AB Dor C when younger age estimates are used.
