Rotation Velocities of Red and Blue Field Horizontal-Branch Stars

  title={Rotation Velocities of Red and Blue Field Horizontal-Branch Stars},
  author={Bradford Bartholomew Behr},
  journal={Astrophysical Journal Supplement Series},
  • B. Behr
  • Published 11 July 2003
  • Physics
  • Astrophysical Journal Supplement Series
We present measurements of the projected stellar rotation velocities (v sin i) of a sample of 45 candidate field horizontal-branch (HB) stars spanning a wide range of effective temperatures, from red HB stars with Teff 5000 K to blue HB stars with Teff of 17,000 K. Among the cooler blue HB stars (Teff = 7500-11500 K), we confirm prior studies showing that, although a majority of stars rotate at v sin i < 15 km s-1, there exists a subset of fast rotators with v sin i as high as 30-35 km s-1. All… 
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