Photoeletric and CCD photometry of 3 and S0 galaxies.
Abstract
We present BR photoelectric photometry for 352 E and S0 galaxies that are part of a large survey of the properties and peculiar motions of galaxies in distant clusters. Repeat measurements show our internal errors to be 2-3 per cent in B and R and 1-2 per cent in B - R. Comparisons of BR and BVR reductions for 10 galaxies also observed in V show small systematic errors due to differences between the spectral energy distributions of stars and galaxies. External comparisons with B - V colours in the literature confirm that these colours are good to 1 per cent. We also describe R-band CCD observations for 95 of the galaxies and place these on a BR photometric system for photoelectric and CCD photometry, with a common zero-point good to better than 1 per cent. We find the rms precision of both our photoelectric and CCD R magnitudes to be 2-3 per cent for galaxies as faint as R ~ 15. Errors in galaxy magnitudes of this order introduce errors of <~ 2 per cent into D_n_-σ distance estimates, corresponding to errors in peculiar velocities for single galaxies of <~ 200 km s^-1^ at a distance of 10 000 km s^-1^.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- May 1993
- DOI:
- Bibcode:
- 1993MNRAS.262..475C
- Keywords:
-
- Astronomical Photometry;
- Charge Coupled Devices;
- Electrophotometers;
- Elliptical Galaxies;
- Galactic Clusters;
- Distance;
- Magnitude;
- Red Shift;
- Astronomy