Highlight talk at the international conference Röntgenstrahlung from the Universe Würzburg, September 1995
published in MPE report 263 (eds. H.U. Zimmermann, J. Trümper, & H.W. Yorke), p. 17
We present ROSAT observations of 30 Ae/Be stars, about half of which were detected as X-ray sources with rather high X-ray luminosities up to 10^32 erg/sec. The X-ray spectra and hardness ratios indicate plasma temperatures of 10^7 K, typical for coronal emission.
The high detection rate of X-ray emission from Ae/Be stars is surprising, if the above reasoning is correct. We discuss several possibilities for the origin of the X-ray emission: Shock interaction of the Ae/Be star stellar wind with remnant circumstellar matter, coronal emission caused by a shear dynamo, and unresolved T Tauri companions.