A Five-year Spectroscopic and Photometric Campaign on the Prototypical α Cygni Variable and A-type Supergiant Star Deneb

  title={A Five-year Spectroscopic and Photometric Campaign on the Prototypical $\alpha$ Cygni Variable and A-type Supergiant Star Deneb},
  author={Noel D. Richardson and Nancy Dunlap Morrison and Erin Kryukova and Saul J. Adelman},
  journal={The Astronomical Journal},
Deneb is often considered the prototypical A-type supergiant and is one of the visually most luminous stars in the Galaxy. A-type supergiants are potential extragalactic distance indicators, but the variability of these stars needs to be better characterized before this technique can be considered reliable. We analyzed 339 high-resolution echelle spectra of Deneb obtained over the five-year span of 1997 through 2001 as well as 370 Stromgren photometric measurements obtained during the same time… Expand

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