Einstein solid state spectrometer observation of the peculiar red dwarf Wolf 630 AB

Abstract

Wolf 630 AB is a double and perhaps triple star with a predominant dM 3.5e spectrum. It is one of the relatively strong red dwarf X-ray sources. The 0.5 to 4 keV spectral data for a steady, non-flaring flux are interpreted in terms of emission from thin thermal plasma with a dominant temperature of approximately 6,500,000 K. Both in temperature and average surface flux the quiescent corona is similar to that of the low temperature component found for RS Canum Venaticorum binaries. There is an indication of additional emission above 10 to the 7th power K, but the ratio of high to low temperature emission is smaller than for typical RS CVn systems. The solid state spectrometer observed the spectrum of only one other red dwarf, Ad Leo, which is very similar to that observed for Wolf 630 AB