Evidence for galaxy-galaxy interactions as an active agent of the Butcher-Oemler effect at a redshift of 0. 2

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/166496· OSTI ID:6753223

Lavery, R J; Henry, J P

The spectra and images of 10 blue emission-line galaxies observed in Abell 963 (5), Abell 2111 (4), and Abell 2125 (1) are presented. A wide range in the spectral properties of the galaxies is found, yet the large majority of the galaxies has spectra which are consistent with very recent star formation. Only one of the 10 galaxies appears to contain an active nucleus. Since star formation is now occurring in these galaxies, residual effects from the triggering mechanism may still be apparent. Images of these emission-line galaxies show that several appear to be members of interacting systems. Others show evidence for possible interactions, either being somewhat morphologically disturbed or having disturbed neighbor galaxies. To test the idea of interactions, a nearest neighbor analysis on these emission-line galaxies and a sample of red galaxies was performed using the Kolmogorov-Smirnov test. The emission-line galaxies have closer neighbor galaxies than the red galaxy sample at greater than the 98 percent level of confidence. From this result and from the images themselves, it is concluded that galaxy-galaxy interactions can induce bursts of star formation and are an active agent of the Butcher-Oemler effect at redshifts near 0.2. These interactions may be the primary cause of the B-O effect. 40 references.

• Research Organization: Hawaii Univ., Honolulu (USA)
• OSTI ID: 6753223
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 330; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BASIC INTERACTIONS
EMISSION SPECTRA
GALACTIC EVOLUTION
GALAXIES
GALAXY CLUSTERS
GRAVITATIONAL INTERACTIONS
IMAGES
INTERACTIONS
RED SHIFT
SPECTRA
STAR EVOLUTION