The X-Ray Origin of Herbig AeBe Systems: New Insights

Abstract

We present a statistical study of the X-Ray emission toward 22 Herbig AeBe stars using the Chandra archive. We probe the origin of the X-Rays toward Herbig stars: are they intrinsic? This question is addressed by correlations between the physical stellar properties and the X-Ray emission. There is a weak correlation between the continuum radio emission at lambda = 3.6cm and Lx, which suggests that the X-Ray emission depends upon the source. On the other hand, no correlation was found with the stellar rotational period, but that only excludes solar-like magnetic activity as the origin of the X-Rays. Most importantly, the X-Ray luminosity of Herbig AeBe stars have a different distribution than T Tauri stars, suggesting X-Ray emission from an unseen late type star companion can be ruled out with an 80% confidence level. This implies that the Herbig AeBe stars must have magnetic activity. In addition, we report the observation of five sources for the first time, three detections.