Sloan/Johnson‐Cousins/2MASS Color Transformations for Cool Stars

We present multicolor transformations and photometric parallaxes for a sample of 40 low‐mass dwarfs selected from the Sloan Digital Sky Survey (SDSS) and the General Catalogue of Trigonometric Stellar Parallaxes. Our sample was reobserved at the Manastash Ridge Observatory (MRO) using both Sloan and Johnson‐Cousin filters, and color transformations between the two photometric systems were derived. A subset of the sample had previously measured Johnson‐Cousins photometry and parallaxes as well as 2MASS photometry. We observed these stars at MRO using Sloan filters and used these data to derive photometric parallax relations as well as SDSS/Johnson‐Cousins/2MASS color transformations. We present the data and derived transformations for use in future low‐mass‐star studies.