UV-by photometry in M39 and delta Lyrae

Journal Article · Tue May 01 04:00:00 EDT 1984 · Astron. J.; (United States)

OSTI ID:6877859

Anthony-Twarog, B J

Photoelectric UV-by observations have been obtained for stars in the mid-B to early-A spectral range in the fields of M39 and delta Lyrae. The color and luminosity calibrations of Crawford for B, A, and F stars have been employed, as well as the new calibration for A0 stars of Hilditch et al. (1983). The resulting distance modulus for M39 is 7.23, with a mean E(b-y) color excess of 0.025. A distance modulus of 7.29 and a mean reddening of 0.032 has been derived for ten stars in the field of delta Lyrae, but the existence of a cluster is not strongly indicated in the present study. Comparison of photometric and rotational velocity data for the M39 stars confirms a correlation between deltac/sub 0/ and rotational velocity for A and A0 stars, and suggests that an evolutionary correction of only -3deltac/sub 0/ be employed for stars in both spectral classes.

• Research Organization: Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045
• OSTI ID: 6877859
• Journal Information: Astron. J.; (United States), Journal Name: Astron. J.; (United States) Vol. 89:5; ISSN ANJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CALIBRATION
DISTANCE
MOTION
PHOTOMETRY
ROTATION
STAR CLUSTERS
STAR EVOLUTION