The calibration of intrinsic colours in UVBY photometry.
Abstract
On the basis of photoelectric uvby observations of NGC 1502 and NGC 2169 it is shown that the m0 and (u-b)0 values for early-type members of young open clusters critically depend on the set of standard stars selected to perform the transformation of instrumental to standard magnitudes. In particular, the values of these indices may contain large errors when the calibrations need to be extrapolated due to the cluster reddening. It is shown that these errors should be greatly reduced by using a calibration for (u-b), instead of m1.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 1989
- Bibcode:
- 1989A&A...219..121D
- Keywords:
-
- Open Clusters;
- Stellar Color;
- Stellar Spectrophotometry;
- Ubv Spectra;
- Visual Photometry;
- Interstellar Extinction;
- Stellar Magnitude;
- Astronomy