HUBBLE SPACE TELESCOPE MORPHOLOGIES OF z {approx} 2 DUST-OBSCURED GALAXIES. II. BUMP SOURCES
Abstract
We present Hubble Space Telescope imaging of 22 ultra-luminous infrared galaxies (ULIRGs) at z {approx} 2 with extremely red R - [24] colors (called dust-obscured galaxies, or DOGs) which have a local maximum in their spectral energy distribution (SED) at rest-frame 1.6 {mu}m associated with stellar emission. These sources, which we call 'bump DOGs', have star formation rates (SFRs) of 400-4000 M{sub sun} yr{sup -1} and have redshifts derived from mid-IR spectra which show strong polycyclic aromatic hydrocarbon emission-a sign of vigorous ongoing star formation. Using a uniform morphological analysis, we look for quantifiable differences between bump DOGs, power-law DOGs (Spitzer-selected ULIRGs with mid-IR SEDs dominated by a power law and spectral features that are more typical of obscured active galactic nuclei than starbursts), submillimeter-selected galaxies, and other less-reddened ULIRGs from the Spitzer Extragalactic First Look Survey. Bump DOGs are larger than power-law DOGs (median Petrosian radius of 8.4 {+-} 2.7 kpc versus 5.5 {+-} 2.3 kpc) and exhibit more diffuse and irregular morphologies (median M{sub 20} of -1.08 {+-} 0.05 versus -1.48 {+-} 0.05). These trends are qualitatively consistent with expectations from simulations of major mergers in which merging systems during the peak SFR period evolve from M{sub 20}more »
- Authors:
-
- Steward Observatory, Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)
- National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States)
- Spitzer Science Center, California Institute of Technology, MS 220-6, Pasadena, CA 91125 (United States)
- School of Physics, Monash University, Clayton, Victoria 3800 (Australia)
- Jet Propulsion Laboratory, California Institute of Technology, MC 169-327, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
- Georgia Southern University, P.O. Box 8031, Statesboro, GA (United States)
- Laboratoire AIM-Paris-Saclay, CEA-CNRS-Universite Paris Diderot, CEA Saclay, Gif-sur-Yvette, 91191 (France)
- Caltech Optical Observatories, California Institute of Technology, Pasadena, CA 91125 (United States)
- Astronomy Department, Cornell University, Ithaca, NY 14853 (United States)
- Publication Date:
- OSTI Identifier:
- 21576802
- Resource Type:
- Journal Article
- Journal Name:
- Astrophysical Journal
- Additional Journal Information:
- Journal Volume: 733; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/733/1/21; Journal ID: ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DUSTS; GALACTIC EVOLUTION; GALAXIES; MORPHOLOGY; RED SHIFT; EVOLUTION
Citation Formats
Bussmann, R S, Dey, Arjun, Lotz, J, Jannuzi, B T, Armus, L, Desai, V, Soifer, B T, Brown, M J. I., Eisenhardt, P, Higdon, J, Higdon, S, Le Floc'h, E, Melbourne, J, and Weedman, D. HUBBLE SPACE TELESCOPE MORPHOLOGIES OF z {approx} 2 DUST-OBSCURED GALAXIES. II. BUMP SOURCES. United States: N. p., 2011.
Web. doi:10.1088/0004-637X/733/1/21.
Bussmann, R S, Dey, Arjun, Lotz, J, Jannuzi, B T, Armus, L, Desai, V, Soifer, B T, Brown, M J. I., Eisenhardt, P, Higdon, J, Higdon, S, Le Floc'h, E, Melbourne, J, & Weedman, D. HUBBLE SPACE TELESCOPE MORPHOLOGIES OF z {approx} 2 DUST-OBSCURED GALAXIES. II. BUMP SOURCES. United States. https://doi.org/10.1088/0004-637X/733/1/21
Bussmann, R S, Dey, Arjun, Lotz, J, Jannuzi, B T, Armus, L, Desai, V, Soifer, B T, Brown, M J. I., Eisenhardt, P, Higdon, J, Higdon, S, Le Floc'h, E, Melbourne, J, and Weedman, D. 2011.
"HUBBLE SPACE TELESCOPE MORPHOLOGIES OF z {approx} 2 DUST-OBSCURED GALAXIES. II. BUMP SOURCES". United States. https://doi.org/10.1088/0004-637X/733/1/21.
@article{osti_21576802,
title = {HUBBLE SPACE TELESCOPE MORPHOLOGIES OF z {approx} 2 DUST-OBSCURED GALAXIES. II. BUMP SOURCES},
author = {Bussmann, R S and Dey, Arjun and Lotz, J and Jannuzi, B T and Armus, L and Desai, V and Soifer, B T and Brown, M J. I. and Eisenhardt, P and Higdon, J and Higdon, S and Le Floc'h, E and Melbourne, J and Weedman, D},
abstractNote = {We present Hubble Space Telescope imaging of 22 ultra-luminous infrared galaxies (ULIRGs) at z {approx} 2 with extremely red R - [24] colors (called dust-obscured galaxies, or DOGs) which have a local maximum in their spectral energy distribution (SED) at rest-frame 1.6 {mu}m associated with stellar emission. These sources, which we call 'bump DOGs', have star formation rates (SFRs) of 400-4000 M{sub sun} yr{sup -1} and have redshifts derived from mid-IR spectra which show strong polycyclic aromatic hydrocarbon emission-a sign of vigorous ongoing star formation. Using a uniform morphological analysis, we look for quantifiable differences between bump DOGs, power-law DOGs (Spitzer-selected ULIRGs with mid-IR SEDs dominated by a power law and spectral features that are more typical of obscured active galactic nuclei than starbursts), submillimeter-selected galaxies, and other less-reddened ULIRGs from the Spitzer Extragalactic First Look Survey. Bump DOGs are larger than power-law DOGs (median Petrosian radius of 8.4 {+-} 2.7 kpc versus 5.5 {+-} 2.3 kpc) and exhibit more diffuse and irregular morphologies (median M{sub 20} of -1.08 {+-} 0.05 versus -1.48 {+-} 0.05). These trends are qualitatively consistent with expectations from simulations of major mergers in which merging systems during the peak SFR period evolve from M{sub 20} = -1.0 to M{sub 20} = -1.7. Less-obscured ULIRGs (i.e., non-DOGs) tend to have more regular, centrally peaked, single-object morphologies rather than diffuse and irregular morphologies. This distinction in morphologies may imply that less-obscured ULIRGs sample the merger near the end of the peak SFR period. Alternatively, it may indicate that the intense star formation in these less-obscured ULIRGs is not the result of a recent major merger.},
doi = {10.1088/0004-637X/733/1/21},
url = {https://www.osti.gov/biblio/21576802},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 733,
place = {United States},
year = {Fri May 20 00:00:00 EDT 2011},
month = {Fri May 20 00:00:00 EDT 2011}
}