Infrared emission in paired galaxies. II - Luminosity functions and far-infrared properties

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view Abstract Citations (115) References (45) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Infrared Emission in Paired Galaxies. II. Luminosity Functions and Far-Infrared Properties Xu, Cong ; Sulentic, Jack W. Abstract We have studied the optical and FIR luminosity functions, as well as other FIR statistics, for a sample of galaxy pairs selected from the Catalogue of Isolated Pairs of Galaxies in the Northern Sky (CPG). A comparison has been made with two control samples selected from the Catalogue of Isolated Galaxies (CIG). We find the following: 1. Approximately 10% of field galaxies are in isolated pairs. 2. The optical luminosity functions for late-type (SS), early-type (EE), and mixed (ES) pairs show enhancement at the bright end relative to control samples. 3. The optical luminosity function reveals a complete absence of dwarf EE pairs in the CPG (fainter than M_pg_ = -19). 4. SS pairs dominate the bright end of the IRAS luminosity function (L_fir_ > 2 x 10^11^ L_sun_ ), while their contribution to the faint end (L_fir_ < 10^10^ L_sun_) is small (< 10%). 5. The contribution from the S galaxies in ES pairs to the IRAS luminosity function is never greater than 10%. 6. Spiral/irregular galaxies in SS and ES pairs are on average about 3 times brighter in the FIR than isolated galaxies of the same types. 7. Compared to a sample of synthetic SS pairs, the FIR luminosity function of SS pairs shows a depression in the faint part (L_fir_ <= 10^10^ L_sun_) and an enhancement in the bright part (L_fir_ >= 10^10^ L_sun _ ), which indicates an enhancement in the FIR emission. 8. SS pairs also show statistically significant enhancements in their mean FIR to optical luminosity ratio (~ 3 σ) and FIR color ratio (~ 5 σ), compared to isolated spiral/irregular galaxies. 9. SS pairs with signs of interaction and with component separation less than the diameter of the primary show significantly higher mean FIR-to-optical luminosity ratio and mean FIR color ratio compared not only with isolated spiral/irregular galaxies, but also with other SS pairs. These "close-interacting" (CLO) pairs represent ~ 40% of all SS pairs in the CPG. 10. Only one component (the FIR bright component) in wide SS pairs (SS pairs other than CLO) is (marginally) FIR enhanced. A considerable number of CLO SS pairs show evidence for enhancement in both components. Publication: The Astrophysical Journal Pub Date: June 1991 DOI: 10.1086/170132 Bibcode: 1991ApJ...374..407X Keywords: Far Infrared Radiation; Galactic Radiation; Interacting Galaxies; Luminous Intensity; Galactic Structure; Infrared Astronomy Satellite; Star Formation; Astrophysics; GALAXIES: CLUSTERING; GALAXIES: STELLAR CONTENT; INFRARED: SOURCES; LUMINOSITY FUNCTION full text sources ADS | data products SIMBAD (66) NED (64) Associated Works (2) Part 1 Part 2