HD 147010:The AP star in the reflection nebula vdB 102 in upper scorpius region

Abstract

HD 147010, which is in the reflection nebula vdB 102, has been found to be a hot Ap silicon star rather than a normal A supergiant. From the UBV and JHK photometry of the star, color excess E(B-V) of 0.29 and the ratio of total-to-selective absorption R of 4.3 have been obtained. The high value of R implies bigger grain size and also confirms the association of the star with the nebula. The dereddened colors of the star can be fitted to a theoretical energy distribution with an effective temperature of approximately 13,000 + or - 500 K and log g = 3.6 + or - 0.2. HD 147010 has also been found to be a spectrum variable; in particular, lines of Cr II show large intensity variations.