Analysis of CHEOPS light curves for eclipsing binaries with very low mass stars

CHOPS是欧空局S级任务，于2019年12月发射。这是第一次致力于通过对已知拥有行星的明亮恒星进行超高精度光度测量来搜索系外行星凌日的任务。CHOPS上80%的时间(~17500轨道)被分配给保证时间的观测，其中~500轨道被分配用于观测约30个具有极低质量伴星的食双星。通过对凌日系外行星的观测，发现了大量有凌日M矮星伴星的太阳型恒星。这些“EBLM”(食双星，低质量)系统是使用与凌日系外行星相同的技术来校准极低质量恒星的质量-半径-金属丰度关系的理想系统。目前对这种关系的定义非常模糊，而且已经变得迫切需要改善它，因为很明显，低质量恒星在宜居带拥有比大质量恒星更多的岩石行星，而且详细研究这些行星要容易得多。

CHEOPS is an ESA S-class mission that was launched in December 2019. It is the first mission dedicated to searching for exoplanetary transits by performing ultrahigh precision photometry on bright stars already known to host planets. 80% of the time on CHEOPS ( ~17500 orbits) is allocated for Guaranteed Time Observations, including ~500 orbits assigned to observe about 30 eclipsing binaries with very low mass companions. Solar-type stars with transiting M-dwarf companions are found in large numbers by surveys for transiting exoplanets. These "EBLM" (eclipsing binary, low-mass) systems are ideal for calibrating the mass-radius-metallicity relation for very low mass stars using the same techniques employed for transiting exoplanets. This relation is very poorly defined currently, and it has become urgent to improve it since it has become clear that low mass stars host more rocky planets in the habitable zone than more massive stars, and it is much easier to study these planets in detail.