Altair – the “hottest” magnetically active star in X-rays

  title={Altair – the “hottest” magnetically active star in X-rays},
  author={J. Robrade and J{\"u}rgen H. M. M. Schmitt},
  journal={Astronomy and Astrophysics},
Context. The onset of stellar magnetic activity is related to the operation of dynamo processes that require the development of an outer convective layer. This transition of stellar interior structure is expected to occur in late A-type stars. Aims. The A7 star Altair is one of the hottest magnetically active stars. Its proximity to the Sun allows a detailed investigation of a corona in X-rays for a star with a shallow convection zone. Methods. We used a deep XMM-Newton observation of Altair… 

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