Radius relations for low-metallicity M-dwarf stars

M subdwarfs are low-metallicity M dwarfs that typically inhabit the halo population of the Galaxy. Metallicity controls the opacity of stellar atmospheres; in metal-poor stars,...M型亚矮星（M subdwarfs）是一类低金属丰度的M型矮星，通常分布于银河系的银晕星族中。金属丰度决定恒星大气的不透明度；在贫金属恒星中，……