HERSCHEL OBSERVATIONS OF MAJOR MERGER PAIRS AT z = 0: DUST MASS AND STAR FORMATION

Journal Article · Mon Feb 15 04:00:00 EST 2016 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.3847/0067-0049/222/2/16· OSTI ID:22520002

Cao, Chen ^[1]; Xu, Cong Kevin; Lu, Nanyao; Mazzarella, Joe ^[2]; Domingue, Donovan; Ronca, Joseph; Jacques, Allison ^[3]; Buat, Veronique ^[4]; Cheng, Yi-Wen ^[5]; Gao, Yu ^[6]; Huang, Jiasheng ^[7]; Jarrett, Thomas H. ^[8]; Lisenfeld, Ute ^[9]; Sun, Wei-Hsin ^[10]; Wu, Hong ^[11]

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1. School of Space Science and Physics, Shandong University, Weihai, Weihai, Shandong 264209 (China)
2. Infrared Processing and Analysis Center, California Institute of Technology 100-22, Pasadena, CA 91125 (United States)
3. Georgia College and State University, CBX 82, Milledgeville, GA 31061 (United States)
4. Laboratoire d’Astrophysique de Marseille—LAM, Université d’Aix-Marseille and CNRS, UMR7326, 38 rue F. Joliot-Curie, F-13388 Marseille Cedex 13 (France)
5. Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan (China)
6. Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, Nanjing 210008 (China)
7. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
8. Astronomy Department, University of Cape Town, Rondebosch 7701 (South Africa)
9. Departamento de Fisica Teórica y del Cosmos, Universidad de Granada (Spain)
10. Institute of Astrophysics, National Taiwan University and The National Museum of Natural Science, Taiwan (China)
11. National Astronomical Observatories, Chinese Academy of Sciences, Beijing (China)

We present Herschel PACS and SPIRE far-infrared (FIR) and submillimeter imaging observations for a large K-band selected sample of 88 close major-merger pairs of galaxies (H-KPAIRs) in 6 photometric bands (70, 100, 160, 250, 350, and 500 μm). Among 132 spiral galaxies in the 44 spiral–spiral (S+S) pairs and 44 spiral–elliptical (S+E) pairs, 113 are detected in at least 1 Herschel band. The star formation rate (SFR) and dust mass (M{sub dust}) are derived from the IR SED fitting. The mass of total gas (M{sub gas}) is estimated by assuming a constant dust-to-gas mass ratio of 0.01. Star-forming spiral galaxies (SFGs) in S+S pairs show significant enhancements in both specific star formation rate (sSFR) and star formation efficiency (SFE), while having nearly the same gas mass compared to control galaxies. On the other hand, for SFGs in S+E pairs, there is no significant sSFR enhancement and the mean SFE enhancement is significantly lower than that of SFGs in S+S pairs. This suggests an important role for the disk–disk collision in the interaction-induced star formation. The M{sub gas} of SFGs in S+E pairs is marginally lower than that of their counterparts in both S+S pairs and the control sample. Paired galaxies with and without interaction signs do not differ significantly in their mean sSFR and SFE. As found in previous works, this much larger sample confirms that the primary and secondary spirals in S+S pairs follow a Holmberg effect correlation on sSFR.

• OSTI ID: 22520002
• Journal Information: Astrophysical Journal, Supplement Series, Journal Name: Astrophysical Journal, Supplement Series Journal Issue: 2 Vol. 222; ISSN 0067-0049; ISSN APJSA2
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
COSMIC DUST
EFFICIENCY
GALAXIES
MASS
PHOTOMETRY
STAR EVOLUTION
STARS