Cracking the Conundrum of F-supergiant Coronae

  title={Cracking the Conundrum of F-supergiant Coronae},
  author={Thomas R. Ayres},
  journal={The Astrophysical Journal},
  • T. Ayres
  • Published 1 September 2016
  • Physics
  • The Astrophysical Journal
Chandra X-ray and HST far-ultraviolet (FUV) observations of three early-F supergiants have shed new light on a previous puzzle involving a prominent member of the class: α Persei (HD 20902: F5 Ib). The warm supergiant is a moderately strong, hard coronal ( K) X-ray source, but has 10 times weaker “subcoronal” Si iv 1393 Å ( K) emissions than early-G supergiants of similar high-energy properties. The α Per X-ray excess was speculatively ascribed to a close-in hyperactive G-dwarf companion, which… 

The evolved fast rotator Sargas

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  • T. Ayres
  • Physics
    The Astrophysical Journal
  • 2021
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