ACTIVE GALACTIC NUCLEI CLUSTERING IN THE LOCAL UNIVERSE: AN UNBIASED PICTURE FROM SWIFT-BAT
- Max Planck Institut fuer Extraterrestrische Physik, D-85478 Garching (Germany)
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)
- University of California, Center for Astrophysics and Space Sciences, San Diego, 9500 Gilman Dr., La Jolla, CA 92093 (United States)
- Instituto de AstronomIa, Universidad Nacional Autonoma de Mexico, Ensenada, Mexico-P.O. Box 439027, San Ysidro, CA 92143 (United States)
- Max Planck Institut fuer Astrophysik, D-85478 Garching (Germany)
We present the clustering measurement of hard X-ray selected active galactic nuclei (AGNs) in the local universe. We used a sample of 199 sources spectroscopically confirmed, detected by Swift-BAT in its 15-55 keV all-sky survey. We measured the real space projected autocorrelation function (ACF) and detected a signal significant on projected scales lower than 200 Mpc h {sup -1}. We measured a correlation length of r{sub 0} = 5.56{sup +0.49}{sub -0.43} Mpc h {sup -1} and a slope {gamma} = 1.64{sup -0.08}{sub -0.07}. We also measured the ACF of Type I and Type II AGNs and found higher correlation length for Type I AGNs. We have a marginal evidence of luminosity dependent clustering of AGNs, as we detected a larger correlation length of luminous AGNs than that of low-luminosity sources. The corresponding typical host dark matter halo masses of Swift-BAT are {approx} log(M{sub DMH}){approx} 12-14 h {sup -1} M/M{sub sun}, depending on the subsample. For the whole sample, we measured log(M{sub DMH}){approx} 13.15 h {sup -1} M/M{sub sun} which is the typical mass of a galaxy group. We estimated that the local AGN population has a typical lifetime {tau}{sub AGN{approx}}0.7 Gyr, it is powered by supermassive black hole with mass M{sub BH{approx}}(1-10) x 10{sup 8} M{sub sun} and accreting with very low efficiency, log({epsilon}){approx}-2.0. We also conclude that local AGN host galaxies are typically red-massive galaxies with stellar mass of the order (2-80) x 10{sup 10} h {sup -1} M{sub sun}. We compared our results with clustering predictions of merger-driven AGN triggering models and found a good agreement.
- OSTI ID:
- 21451069
- Journal Information:
- Astrophysical Journal Letters, Vol. 716, Issue 2; Other Information: DOI: 10.1088/2041-8205/716/2/L209; ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
Similar Records
OCCUPATION OF X-RAY-SELECTED GALAXY GROUPS BY X-RAY ACTIVE GALACTIC NUCLEI
THE SPATIAL CLUSTERING OF ROSAT ALL-SKY SURVEY ACTIVE GALACTIC NUCLEI. III. EXPANDED SAMPLE AND COMPARISON WITH OPTICAL ACTIVE GALACTIC NUCLEI
Related Subjects
COSMOLOGY AND ASTRONOMY
BLACK HOLES
GALAXY NUCLEI
HARD X RADIATION
LUMINOSITY
MASS
NONLUMINOUS MATTER
UNIVERSE
X-RAY GALAXIES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ELECTROMAGNETIC RADIATION
GALAXIES
IONIZING RADIATIONS
MATTER
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS
X RADIATION