2012ApJ...751...72D

Query : 2012ApJ...751...72D

2012ApJ...751...72D - Astrophys. J., 751, 72 (2012/May-3)

A tale of two populations: the contribution of merger and secular processes to the evolution of active galactic nuclei.

DRAPER A.R. and BALLANTYNE D.R.

Abstract (from CDS):

Due to the co-evolution of supermassive black holes and their host galaxies, understanding the mechanisms that trigger active galactic nuclei (AGNs) is imperative to understanding galaxy evolution and the formation of massive galaxies. It is observationally difficult to determine the trigger of a given AGN due to the difference between the AGN lifetime and triggering timescales. Here, we utilize AGN population synthesis modeling to determine the importance of different AGN triggering mechanisms. An AGN population model is computed by combining an observationally motivated AGN triggering rate and a theoretical AGN light curve. The free parameters of the AGN light curve are constrained by minimizing a χ2 test with respect to the observed AGN hard X-ray luminosity function. The observed black hole space density, AGN number counts, and X-ray background spectrum are also considered as observational constraints. It is found that major mergers are not able to account for the entire AGN population. Therefore, non-merger processes, such as secular mechanisms, must also trigger AGNs. Indeed, non-merger processes are the dominant AGN triggering mechanism at z ≲ 1-1.5. Furthermore, the shape and evolution of the black hole mass function of AGNs triggered by major mergers are intrinsically different from the shape and evolution of the black hole mass function of AGNs triggered by secular processes.

Abstract Copyright: ∼

Journal keyword(s): galaxies: active - galaxies: Seyfert - quasars: general - X-rays: diffuse background

Simbad objects: 1

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Number of rows : 1
N Identifier Otype ICRS (J2000)
RA 		ICRS (J2000)
DEC 		Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024 		#notes
1 NAME Lockman Hole reg 10 45 00.0 +58 00 00           ~ 841 0

Query : 2012ApJ...751...72D

Basic data :
NAME Lockman Hole -- Region defined in the Sky
Origin of the objects types :

(Ref) Object type as listed in the reference "Ref"
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() Anterior to 2007, before we can link the objet type to a reference, or given by the CDS team in some particular cases

Other object types: 		reg ([SFD98])
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
ICRS coord. (ep=J2000) : 		10 45 00.0 +58 00 00 [ ] E 2011ApJ...734...99H
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
FK4 coord. (ep=B1950 eq=1950) : 		10 41 51.0 +58 15 47 [ ]
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
Gal coord. (ep=J2000) : 		149.7686 +52.0314 [ ]
SIMBAD within arcmin
', {sourceSize:12, color:'#30a090'})); aladin.on('objectClicked', function(object) { var objName=object.data.MAIN_ID; aladin.showPopup(object.ra,object.dec,'',''+ objName+''); });" title="Show Simbad objects"> Overlay Simbad points in this preview
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NAME Lockman Hole NAME the Hole NAME the LJM Hole [SFD98] J1048+5702

References (841 between 1850 and 2024) (Total 841)
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