The team noticed that the same line features are also observed at SS 433, a close binary consisting of an A-type star
and most probably a black hole with a mass less than 10 times that of the Sun.
We have been studying through 3-D global simulations the nature of both differential rotation and dynamo action that can be achieved in G-type stars like the sun by turbulent convection in their outer envelopes, and also by core convection in more massive A-type stars
Researchers at the California Institute of Technology (Caltech), surveyed about 300 stars, and focussed on those dubbed "retired" A-type stars
that are more than one and a half times more massive than the sun.