Photometry of NGC 4103
Abstract
The southern galactic cluster NGC 4103 has been studied photometrically. For 512 stars brighter than V = 17m magnitudes and colours are given. Spectral types are derived for 17 of the brightest using U, B, V photometry. Spectroscopic observation of star 12 reveals MK . Probably no stars having types earlier than B2 exist in the cluster. The mean colour excess = . The apparent distance modulus was found to be . With an absorption of I.e the true distance modulus and the distance are and 1600 parsecs respectively. An age of 27 X 10^6 years from the turn off point on the main sequence was found. The eclipsing variable Al Crucis is the 5th brightest star of the cluster and almost certainly a member. Popper and Thackeray observed line doubling in the spectrum (B2IV + ...) of this star.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- 1969
- DOI:
- 10.1093/mnras/146.3.329
- Bibcode:
- 1969MNRAS.146..329W