Effects of interactions on spiral galaxies. II. Disk star-formation rates

Journal Article · Fri May 01 04:00:00 EDT 1987 · Astron. J.; (United States)

DOI:https://doi.org/10.1086/114384· OSTI ID:6018257

Kennicutt, Jr, R C; Roettiger, K A; Keel, W C; Van der hulst, J M; Hummel, E

H-alpha emission-line and IRAS far-IR observations of interacting spiral and irregular galaxies are here used to assess the influence of interactions on their global star-formation rates. Two samples of interacting galaxies were observed: a complete sample of close pairs, and an Arp atlas sample of peculiar systems. When compared to a control sample of single galaxies, both samples of interacting systems exhibit systematically higher levels of H-alpha and infrared emission on average, and a larger dispersion in emission properties. Emission levels in the very active system are much more strongly correlated with the properties of the interaction than with the internal properties of the galaxies themselves. Strong disk emission is almost always accompanied by unusually strong nuclear activity. Simple star-formation burst models can reproduce the observed H-alpha equivalent widths and broadband colors of most of the galaxies. The bursts are relatively short (few times 10 million yr) and rarely involve more than 1-2 percent of a galaxy's total mass. 56 references.

• Research Organization: Minnesota Univ., Minneapolis; Kitt Peak National Observatory, Tucson, AZ; Leiden Rijksuniversiteit, Sterrewacht, Netherlands; Westerbork Radiosterrenwacht, Zwiggelte, Netherlands; Max-Planck-Institut fuer Radioastronomie, Bonn, West Germany
• OSTI ID: 6018257
• Journal Information: Astron. J.; (United States), Journal Name: Astron. J.; (United States) Vol. 93; ISSN ANJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BALMER LINES
BASIC INTERACTIONS
CONFIGURATION
ELECTROMAGNETIC RADIATION
EMISSION SPECTRA
FAR INFRARED RADIATION
GALACTIC EVOLUTION
GALAXIES
GRAVITATIONAL INTERACTIONS
INFRARED RADIATION
INTERACTIONS
LUMINOSITY
MASS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS
SPECTRA
SPIRAL CONFIGURATION
STAR EVOLUTION