X-ray and Radio AGN in Coma Cluster Progenitors

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X-ray and Radio AGN in Coma Cluster Progenitors

• Quyen Nguyen Hart
• University of Colorado at Boulder, Center for
  Astrophysics and Space Astronomy

Collaborators CU-Boulder John Stocke Erica
Ellingson Eric Hallman U. Of Michigan Gus
Evrard
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On the Road to Coma
More Massive Cluster
Why should we follow this road?
Less Massive Cluster
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On the Road to Coma
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Multi-wavelength Study

• Chandra Archival data
• VLA 20-cm maps (new/archival)
• HST archival images
• Apache Point Observatory, 3.5m
• Two color imaging
• (g,r) or (r,i)
• K-short
• Med. Dispersion spectrograph with red/blue
  channels (3500 - 9000 Å)

• Additional sources
• SDSS
• ChaMP
• CNOC-1
• Literature

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Example of DataAbell 963, z0.206
Chandra 0.3-8.0 keV
FIRST
SDSS r
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AGN Luminosity Limits
X-ray LF
1 order below knee
Sazonov Revnivtsev (2004)
X-ray 0.3-8 keV 3 ? 1042 erg s-1
Radio 20 cm 1 ? 1023 W Hz1
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Passive Galaxy Spectrum
APO DIS spec, r 17th
B-band
Ca HK
Na I
Mg I
A-band
APO DIS spec, r 19th
G-band
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Emission-Line Spectrum
O II
Ne III
APO DIS spec, r 18.5th
Ne V
z0.209
H-? N II
Ca HK
O III
S II
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Simple Number Counts

• 12 low-z clusters (0.2 lt z lt 0.5)

TWO Radio AGN per Cluster
ONE Xray AGN per Cluster
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Composite COLOR MAGNITUDE Diagram
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X-ray AND Radio AGN With optical counterparts (N
100)
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Majority of cluster AGN lies on Cluster Red
Sequence (CRS)
Some X-ray AGN have BLUER colors than CRS
emission-line spectra
Host galaxies of Cluster AGN are bright cluster
galaxies
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AGN Host Galaxies

• Cluster AGN optical colors representative of old,
  red, dead galaxies, ie. Passive ellipticals
• Spectra reveal that in our sample
• X-ray AGN 75 passive galaxy host
• Radio AGN 80 passive galaxy host
• In both cases, only a few AGN would have been
  identified optically

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• ICM EMISSION
• (? - Model)
• Rcore
• 100 kpc
• 400 kpc

Cluster AGN are more centrally concentrated than
red sequence galaxies!
Cluster Red Sequence Galaxies
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In Summary

• Road to Coma is unique sample
• Majority of cluster AGN reside within 500 kpc
• distributed heating in cluster centers?
• Cluster AGN host galaxies are passive ellipticals
  (old, red, dead galaxies!)
• RARE overlap of X-ray and Radio AGN sources
• Different modes of AGN activity?

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Whats next

• AGN population in zgt0.5 sample
• X-ray hardness ratios composite X-ray spectrum
• X-ray and Radio luminosity Functions
• Is there an X-ray bi-variate luminosity function
  similar to radio?
• Input cluster AGN properties in cosmological
  simulations
• This research is supported by Chandra
  Archive/Theory Grant AR8-9013X