Emission-Line Stars of the Orion Population

It is intended to replace the Second Catalog of Herbig and Rao (1972). It gives accurate coordinates (many determined especially for this Catalog), light ranges for known variables, UBVRI data near maximum light, references to ultraviolet, X-ray and radio observations and to light curves, value of v sin i and the radial velocity when known, spectral type, equivalent width of the H-alpha emission line, references to spectral reproductions or scans and spectroscopic studies and to identification charts, and a classification (as a T Tau star, FU Ori object, etc.)