  In the ROSAT all-sky survey 11 HgMn stars were detected as soft X-ray
emitters (Berghoefer, Schmitt & Cassinelli 1996). Prior to ROSAT, X-ray
observations with the Einstein Observatory had suggested that stars in the
spectral range B5-A7 are devoid of X-ray emission. Since there is no X-ray
emitting mechanism available for these stars (also not for HgMn stars), the
usual argument in the case of an X-ray detected star of this spectral type is
the existence of an unseen low-mass companion which is responsible for the
X-ray emission. The purpose of the present work is to use all available data
for our sample of X-ray detected HgMn stars and conclude on the nature of
possible companions.
