Cracking the Conundrum of F-Supergiant Coronae

  title={Cracking the Conundrum of F-Supergiant Coronae},
  author={T. Ayres},
  journal={arXiv: Solar and Stellar Astrophysics},
  • T. Ayres
  • Published 2016
  • Physics, Materials Science
  • arXiv: Solar and Stellar Astrophysics
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: Alpha Persei (HD20902: F5Ib). The warm supergiant is a moderately strong, hard coronal (T~10MK) X-ray source, but has ten times weaker "sub-coronal" Si IV 139 nm (T~80,000 K) emissions than early-G supergiants of similar high-energy properties. The Alpha Per X-ray excess speculatively was ascribed to a close-in hyperactive G… Expand

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