Spectroscopic observations of Arp-Madore interacting galaxies - I. Pairs of comparably sized galaxies.
Abstract
We have obtained nuclear spectra of 129 galaxies, from a sample of 71 pairs of interacting doubles of comparably sized galaxies with IRAS observations. Radial velocities, relative emission-line intensity measurements and optical classifications are presented. Radial velocities for 93 galaxies are determined for the first time and two new Seyferts and one LINER have been identified. We confirm earlier results that a large number of these objects are indeed showing H II region type spectra. We did not find an excess of Seyfert- and LINER-type nuclei in our sample of interacting galaxies, compared to the field isolated disc galaxies. A low LINER detection rate could be due to our IR criteria which favour a strong H II region type activity and make it difficult to detect low-level LINER activity which may be present. However, there is no obvious reason why we did not find the excess of Seyfert-type nuclei which was reported in previous studies of similar galaxy samples. We also did not find a high frequency of one-sided enhanced star-formation activity, suggested by the far-infrared study of the same sample of galaxies. The enhancement of the star-formation activity is more likely to take place in both galaxies, but the strength and/or time-scale and phase of the activity in each of the two galaxies of the pair may differ substantially.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 1992
- DOI:
- 10.1093/mnras/255.4.581
- Bibcode:
- 1992MNRAS.255..581S
- Keywords:
-
- Astronomical Spectroscopy;
- Galactic Nuclei;
- Galactic Structure;
- H Ii Regions;
- Interacting Galaxies;
- Seyfert Galaxies;
- Emission Spectra;
- Infrared Astronomy Satellite;
- Line Spectra;
- Radial Velocity;
- Star Formation Rate;
- Astrophysics