1994A&A...287L..34R

A series of recent papers (Kouveliotou et al., 1994; Sommer et al., 1994; Ryan et al., 1994) have discussed the localization and properties of GRB930131, the brightest gamma ray burst (GRB) observed by the Compton Gamma Ray Observatory (CGRO). Schaefer et al. (1994) have looked for objects in the neighbourhood of this GRB. They have shown that there are two X-ray sources near the CGRO localization, which were identified with the stars HD 106225 and HR 4657. In the present Letter we discuss these two sources in detail. HR 4657 is a visual binary of spectral type F at a distance of 34 pc and it is unlikely to be the source of GRB930131. The object HD 106225 is one of the most active RS CVn type of binaries at a distance of 220 pc and it exhibits surface magnetic activity in all wavelengths from radio to X-rays (Strassmeier et al., 1993). Vahia and Rao (1988) have suggested that the GRBs arise from flares on Magnetically Active Stellar Systems (MASS) consisting of flare stars, RS CVn binaries and cataclysmic variables of which about 300 sources are known. The probability of finding a magnetically active system in the CGRO error box is about 3x10^–3. Other properties of the GRB also agree well with our expectations of flares on such a binary.