TY - JOUR
T1 - Chandra observations of Galaxy Zoo mergers
T2 - Frequency of binary active nuclei in massive mergers
AU - Teng, S.H.
AU - Schawinski, K.
AU - Urry, C.M.
AU - Bonning, E.W.
AU - Simmons, B.D.
AU - Darg, D.W.
AU - Kaviraj, S.
AU - Lintott, C.J.
AU - Oh, K.
AU - Cardamone, C.N.
AU - Keel, W.C.
AU - Treister, E.
PY - 2012/7/10
Y1 - 2012/7/10
N2 - We present the results from a Chandra pilot study of 12 massive galaxy mergers selected from Galaxy Zoo. The sample includes major mergers down to a host galaxy mass of 1011 M ☉ that already have optical active galactic nucleus (AGN) signatures in at least one of the progenitors. We find that the coincidences of optically selected active nuclei with mildly obscured (N H 1.1 × 1022 cm–2) X-ray nuclei are relatively common (8/12), but the detections are too faint (<40 counts per nucleus; f 2-10 keV 1.2 × 10–13 erg s–1 cm–2) to reliably separate starburst and nuclear activity as the origin of the X-ray emission. Only one merger is found to have confirmed binary X-ray nuclei, though the X-ray emission from its southern nucleus could be due solely to star formation. Thus, the occurrences of binary AGNs in these mergers are rare (0%-8%), unless most merger-induced active nuclei are very heavily obscured or Compton thick
AB - We present the results from a Chandra pilot study of 12 massive galaxy mergers selected from Galaxy Zoo. The sample includes major mergers down to a host galaxy mass of 1011 M ☉ that already have optical active galactic nucleus (AGN) signatures in at least one of the progenitors. We find that the coincidences of optically selected active nuclei with mildly obscured (N H 1.1 × 1022 cm–2) X-ray nuclei are relatively common (8/12), but the detections are too faint (<40 counts per nucleus; f 2-10 keV 1.2 × 10–13 erg s–1 cm–2) to reliably separate starburst and nuclear activity as the origin of the X-ray emission. Only one merger is found to have confirmed binary X-ray nuclei, though the X-ray emission from its southern nucleus could be due solely to star formation. Thus, the occurrences of binary AGNs in these mergers are rare (0%-8%), unless most merger-induced active nuclei are very heavily obscured or Compton thick
UR - http://www.scopus.com/inward/record.url?scp=84863325189&partnerID=8YFLogxK
U2 - 10.1088/0004-637X/753/2/165
DO - 10.1088/0004-637X/753/2/165
M3 - Article
AN - SCOPUS:84863325189
SN - 0004-637X
VL - 753
JO - The Astrophysical Journal
JF - The Astrophysical Journal
IS - 2
M1 - 165
ER -