CHANDRA DISCOVERY OF A BINARY ACTIVE GALACTIC NUCLEUS IN Mrk 739
Abstract
We have discovered a binary active galactic nucleus (AGN) in the galaxy Mrk 739 using Chandra and Swift BAT. We find two luminous (L{sub 2-10 keV} = 1.1 x 10{sup 43} and 1.0 x 10{sup 42} erg s{sup -1}), unresolved nuclei with a projected separation of 3.4 kpc (5.''8 {+-} 0.''1) coincident with two bulge components in the optical image. The western X-ray source (Mrk 739W) is highly variable (x 2.5) during the 4 hr Chandra observation and has a very hard spectrum consistent with an AGN. While the eastern component was already known to be an AGN based on the presence of broad optical recombination lines, Mrk 739W shows no evidence of being an AGN in optical, UV, and radio observations, suggesting the critical importance of high spatial resolution hard X-ray observations (>2 keV) in finding these binary AGNs. A high level of star formation combined with a very low L{sub [O{sub III}]/L{sub 2-10 keV}} ratio cause the AGN to be missed in optical observations. {sup 12}CO observations of the (3-2) and (2-1) lines indicate large amounts of molecular gas in the system that could be driven toward the black holes during the violent galaxy collision and be keymore »
- Authors:
-
- Astronomy Department, University of Maryland, College Park, MD (United States)
- Institute for Astronomy, University of Hawaii, Honolulu, HI (United States)
- Department of Physics, Yale University, New Haven, CT (United States)
- Publication Date:
- OSTI Identifier:
- 21562546
- Resource Type:
- Journal Article
- Journal Name:
- Astrophysical Journal Letters
- Additional Journal Information:
- Journal Volume: 735; Journal Issue: 2; Other Information: DOI: 10.1088/2041-8205/735/2/L42; Journal ID: ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; GALAXY NUCLEI; HARD X RADIATION; INTERACTIONS; SPATIAL RESOLUTION; X-RAY GALAXIES; X-RAY SOURCES; COSMIC RAY SOURCES; COSMIC X-RAY SOURCES; ELECTROMAGNETIC RADIATION; GALAXIES; IONIZING RADIATIONS; RADIATION SOURCES; RADIATIONS; RESOLUTION; X RADIATION
Citation Formats
Koss, Michael, Mushotzky, Richard, Veilleux, Sylvain, Vasudevan, Ranjan, Miller, Neal, Trippe, Margaret, Treister, Ezequiel, Sanders, D B, and Schawinski, Kevin. CHANDRA DISCOVERY OF A BINARY ACTIVE GALACTIC NUCLEUS IN Mrk 739. United States: N. p., 2011.
Web. doi:10.1088/2041-8205/735/2/L42.
Koss, Michael, Mushotzky, Richard, Veilleux, Sylvain, Vasudevan, Ranjan, Miller, Neal, Trippe, Margaret, Treister, Ezequiel, Sanders, D B, & Schawinski, Kevin. CHANDRA DISCOVERY OF A BINARY ACTIVE GALACTIC NUCLEUS IN Mrk 739. United States. https://doi.org/10.1088/2041-8205/735/2/L42
Koss, Michael, Mushotzky, Richard, Veilleux, Sylvain, Vasudevan, Ranjan, Miller, Neal, Trippe, Margaret, Treister, Ezequiel, Sanders, D B, and Schawinski, Kevin. 2011.
"CHANDRA DISCOVERY OF A BINARY ACTIVE GALACTIC NUCLEUS IN Mrk 739". United States. https://doi.org/10.1088/2041-8205/735/2/L42.
@article{osti_21562546,
title = {CHANDRA DISCOVERY OF A BINARY ACTIVE GALACTIC NUCLEUS IN Mrk 739},
author = {Koss, Michael and Mushotzky, Richard and Veilleux, Sylvain and Vasudevan, Ranjan and Miller, Neal and Trippe, Margaret and Treister, Ezequiel and Sanders, D B and Schawinski, Kevin},
abstractNote = {We have discovered a binary active galactic nucleus (AGN) in the galaxy Mrk 739 using Chandra and Swift BAT. We find two luminous (L{sub 2-10 keV} = 1.1 x 10{sup 43} and 1.0 x 10{sup 42} erg s{sup -1}), unresolved nuclei with a projected separation of 3.4 kpc (5.''8 {+-} 0.''1) coincident with two bulge components in the optical image. The western X-ray source (Mrk 739W) is highly variable (x 2.5) during the 4 hr Chandra observation and has a very hard spectrum consistent with an AGN. While the eastern component was already known to be an AGN based on the presence of broad optical recombination lines, Mrk 739W shows no evidence of being an AGN in optical, UV, and radio observations, suggesting the critical importance of high spatial resolution hard X-ray observations (>2 keV) in finding these binary AGNs. A high level of star formation combined with a very low L{sub [O{sub III}]/L{sub 2-10 keV}} ratio cause the AGN to be missed in optical observations. {sup 12}CO observations of the (3-2) and (2-1) lines indicate large amounts of molecular gas in the system that could be driven toward the black holes during the violent galaxy collision and be key to fueling the binary AGN. Mrk 739E has a high Eddington ratio of 0.71 and a small black hole (log M{sub BH} = 7.05 {+-} 0.3) consistent with an efficiently accreting AGN. Other than NGC 6240, this stands as the nearest case of a binary AGN discovered to date.},
doi = {10.1088/2041-8205/735/2/L42},
url = {https://www.osti.gov/biblio/21562546},
journal = {Astrophysical Journal Letters},
issn = {2041-8205},
number = 2,
volume = 735,
place = {United States},
year = {Sun Jul 10 00:00:00 EDT 2011},
month = {Sun Jul 10 00:00:00 EDT 2011}
}