We present a statistical parallax analysis of low-mass dwarfs from the Sloan Digital Sky Survey. We calculate absolute r-band magnitudes (Mr ) as a function of color and spectral type and investigate changes in Mr with location in the Milky Way. We find that magnetically active M dwarfs are intrinsically brighter in Mr than their inactive counterparts at the same color or spectral type. Metallicity, as traced by the proxy ζ, also affects Mr , with metal-poor stars having fainter absolute magnitudes than higher metallicity M dwarfs at the same color or spectral type. Additionally, we measure the velocity ellipsoid and solar reflex motion for each subsample of M dwarfs. We find good agreement between our measured solar peculiar motion and previous results for similar populations, as well as some evidence for differing motions of early and late M-type populations in U and W velocities that cannot be attributed to asymmetric drift. The reflex solar motion and the velocity dispersions both show that younger populations, as traced by magnetic activity and location near the Galactic plane, have experienced less dynamical heating. We introduce a new parameter, the independent position altitude (IPA), to investigate populations as a function of vertical height from the Galactic plane. M dwarfs at all types exhibit an increase in velocity dispersion when analyzed in comparable IPA subgroups.
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机译：我们通过Sloan Digital Sky Survey提供了对低质量矮星的统计视差分析。我们计算绝对r波段幅度（Mr）作为颜色和光谱类型的函数，并研究银河系中Mr随位置的变化。我们发现，在相同的颜色或光谱类型下，磁活跃的M矮星在本质上比不活跃的M矮星更亮。代用物ζ追踪到的金属性也影响Mr，在相同颜色或光谱类型下，金属贫乏的恒星的绝对幅度比金属性较高的M矮星的绝对幅度要小。此外，我们测量了M个小矮星每个子样本的椭球速度和太阳反射运动。我们发现测量的太阳奇特运动与相似种群的先前结果之间有很好的一致性，并且一些证据表明U和W速度中早期和晚期M型种群的运动不同，这不能归因于不对称漂移。太阳的反射运动和速度色散都表明，通过磁活动和银河平面附近的位置追踪到的年轻种群的动态加热较少。我们引入了一个新参数，即独立位置高度（IPA），以研究人口相对于银河系垂直高度的函数。当在可比较的IPA子组中进行分析时，所有类型的M矮人都表现出速度散布的增加。
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