The use of the Kitt Peak IDS in determing galaxy redshifts : results for five clusters.
Abstract
The redshifts of 71 galaxies in five clusters determined using the Kitt Peak Image Dissector Scanner (IDS) are presented and the accuracy of velocities determined with the IDS system is discussed. Data were obtained from observations of absorption or emission lines in the range 3600-5400 A using the IDS on a 2.1-m telescope and effective apertures of 3.8 x 10.3 arcsec from galaxies belonging to the AWM 7 = NGC 1129, A 1213, A 1795, A 2589 and A 2666 clusters. Wavelength errors due to mechanical flexure, off-center guiding and spectrum noise are estimated to provide an uncertainty of + or - 1.21 A or 92 km/sec in measurements of a given spectrum, and comparison of the velocities determined by the Kitt Peak IDS with those determined by the Lick IDS supports the error value. Implications of the mean heliocentric redshifts and relativistically correct velocity dispersions obtained for the structure and membership of the AWM 7 cluster are discussed.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 1980
- DOI:
- 10.1086/112721
- Bibcode:
- 1980AJ.....85..626H
- Keywords:
-
- Astronomical Photography;
- Galactic Clusters;
- Image Dissector Tubes;
- Red Shift;
- Ultraviolet Absorption;
- Velocity Distribution;
- Absorption Spectra;
- Galactic Structure;
- Radial Velocity;
- Astronomy