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Discovery of quiescent X-ray emission from HR1099 and RS CVn

Naturevolume 274pages569570 (1978) | Download Citation



OBSERVATIONS with the HEAO 1 satellite have shown that RS CVn binary systems represent a new class of soft X-ray sources1. While the space density of the normal period RS CVn systems is large9, only 26 are known optically10 and, because of their low X-ray luminosity, only about nine of these should be observable from HEAO 1. We present here our discovery of X-ray emission from HR1099 (ref. 2) and the prototype member of this class, RS CVn itself. We also comment on the possible nature of the X-ray emission mechanism in these systems.

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  1. Space Sciences Laboratory and Department of Astronomy, University of California, Berkeley, California, 94720

  2. Space Sciences Laboratory, University of California, Berkeley, California, 94720



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