astro 641 agn mapping the evolution of agn more material: this lecture!
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Astro 641 AGNAstro 641 AGN
Mapping the Evolution Mapping the Evolution of AGNof AGN
More material:
• This lecture!
3C Radio Survey3C Radio Survey
• Third (revised) Cambridge Catalogue of radio sources using extended emission at 178 MHz.
• Low selection frequency: steep spectra
• Survey of all sources north of -5 deg with fR>9 Jy. 328 sources.
• Complete sample: Laing, Riley and Longair (1983). 96% complete to 10 Jy.
V/VV/Vmaxmax Test Test
V/VV/Vmaxmax Test Test• Flux-limited sample --> at small
distances larger luminosity range.
• Solution: compute for each source the max. redshift at which it would still be included in a complete survey --> maximum volume Vmax.
• V/Vmax is a measure of the source position within the observable volume.
• V/Vmax uniform in [0,1] range.
• <V/Vmax>=0.5.
V/VV/Vmaxmax Test Test
Laing, Riley & Longair (1983)
IRASIRAS
de Grijp et al. (1987)
SpitzerSpitzer
Lacy et al. (2004)
Stern DiagramStern Diagram
Stern et al. (2005)
Power-law AGNPower-law AGN
Donley et al. (2008)
Selection: IRAC photometry is well-fit by a line of slope <-0.5
Why does it work?Why does it work?
Hickox et al. (2007)
Fraction of Recovered Fraction of Recovered SourcesSources
Stern et al. (2005)
X-ray Selected SourcesX-ray Selected Sources
Cardamone et al. (2008)
X-ray Selected SourcesX-ray Selected Sources
Cardamone et al. (2008)
X-ray Selected SourcesX-ray Selected Sources
Eckart et al. (2010)
X-ray Selected SourcesX-ray Selected Sources
Eckart et al. (2010)
SummarySummary
Eckart et al. (2010)
24 24 m Selectionm Selection
Brand et al. (2006)
24 24 m Selectionm Selection
Brand et al. (2006)
AGN FractionAGN Fraction
Treister et al. (2006)
AGN Contribution to IR AGN Contribution to IR BackgroundBackground
Treister et al. (2006)
Fiore et al. 2008
Finding Heavily-Obscured AGNFinding Heavily-Obscured AGN
Mid-IRMid-IR X-ray StackingX-ray Stacking
FF2424/F/FRR>1000>1000
FF2424/F/FRR<200<200
• 4 detection in X-ray stack. Hard spectral shape, harder than X-ray detected sources.Good CT AGN candidates.• Similar results found by Daddi et al. (2007)
Rest-Frame StackingRest-Frame Stacking
Good fit with either NH1023cm-2 or combination of CT AGN with star-forming galaxies.
Consistent results with observed-frame stacking.
Treister et al. ApJ 2009c
X-Ray to Mid-IR RatioX-Ray to Mid-IR Ratio
~100x lower ratio for X-ray undetected sources.
Explained by NH~5x1024 to 1025cm-2
Treister et al. ApJ 2009c
Both X-rays and 12µm good tracers of AGN activity.
X-Ray to Mid-IR RatioX-Ray to Mid-IR Ratio
Ratio for sources with L12µm>1043erg/s (~80% of the sources) ~2-3x higher than star-forming galaxies
Treister et al. ApJ 2009c
Near to Mid-IR ColorsNear to Mid-IR Colors- Distributions significantly different- X-ray detected sources much bluer- Average f8/f24=0.2 for X-ray sources and 0.04 for X-ray undetected sample
BluerRedder
Well explained by different viewing angle (30o vs 90o) in the same torus model Can it be star-formation versus AGN?
Treister et al. ApJ 2009c
Near to Mid-IR ColorsNear to Mid-IR Colors
Armus et al. 2007
ULIRG, LINER
ULIRG, Sey2
IRAC ColorsIRAC Colors
[5.8]-[8] (Vega)
z=0-1
z>1
AGNFaint 8 µm
Treister et al. ApJ 2009c
IRAC ColorsIRAC Colors
log (f5.8/f3.6)F
ain
t 8µ
m
Treister et al. ApJ 2009c
Mid-IR/Radio SelectionMid-IR/Radio Selection
Donley et al. (2005)
Mid-IR/Radio SelectionMid-IR/Radio Selection
Park et al. (2008)
Martinez-Sansigre et al. (2005)
Mid-IR/Radio SelectionMid-IR/Radio Selection
Barger et al. (2007)
Putting it all togetherPutting it all together
Hickox et al. (2009)
AGN FractionAGN Fraction
Donley et al. (2008)
q vs IR Lumq vs IR Lum
Kartaltepe et al. (2010)
Stern DiagramStern Diagram
Kartaltepe et al. (2010)
Mid-IR ExcessMid-IR Excess
Kartaltepe et al. (2010)
Redshift and LRedshift and LIRIR DistributionsDistributions
Kartaltepe et al. (2010)
AGN FractionAGN Fraction
Kartaltepe et al. (2010)