Stellar Characteristics Based on the Michigan Spectral Catalogue Classifications. I. The Main-sequence Stars

Representative stellar characteristics for main-sequence spectral types drawn from the Michigan Spectral Catalogue (MSC) are determined using distances from Gaia, V T and B T magnitudes from Tycho, and JHK magnitudes from the Two Micron All Sky Survey. Median ( B − V ) 0 color indices and absolute visual magnitudes M V , and their 16th and 84th percentiles, are computed for 17,003 stars within 200 pc of the Sun spanning B8 V through K4 V. Comparisons with similar studies using smaller and nearer samples reveal good agreement across the full range of overlapping spectral types to within the error estimates of our work; noticeable exceptions within the G stars with respect to the Pecaut & Mamajek values are discussed. Median effective temperatures are derived from ( B − V ) 0 conversions based on the mean of six color–temperature relations and are compared to values given in several published studies to good effect. Our M V values are combined with spectroscopic bolometric corrections to yield median luminosities, which comport well with other programs. Comparisons of our temperatures and luminosities are also made with results from the Tycho and Gaia missions where the agreement is again found to be quite satisfactory over the ranges in which the space-based data are most reliable. In addition, we provide derived radii and masses based on the temperatures and luminosities. Finally, a comparison is made between our fundamental parameters and those tabulated in several commonly used reference sources. Future efforts will focus on the use of MSC data to establish similar, representative parameter values for stars with higher luminosities and/or chemical peculiarities.