SIMBAD references

We describe a new, distance-independent method for calculating the magnetic activity strength in low-mass dwarfs, L_Hα/L_bol. Using a well-observed sample of nearby stars and cool standards spanning spectral type M0.5 to L0, we compute χ, the ratio between the continuum flux near Hα and the bolometric flux, f_λ6560/f_bol. This ratio can be multiplied by the measured equivalent width of the Hα emission line to yield L_Hα/L_bol. We provide χ values for all objects in our sample, and also fits to χ as a function of color and average values by spectral type. This method was used by West et al. to examine trends in magnetic activity strength in low-mass stars.