A Multiwavelength View of Powerful High-Redshift AGN
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Transcript of A Multiwavelength View of Powerful High-Redshift AGN
A Multiwavelength View of Powerful A Multiwavelength View of Powerful High-Redshift AGNHigh-Redshift AGN
Ohad ShemmerOhad Shemmer
Penn State UniversityPenn State University
‘‘Active Galactic Nuclei: From Atoms to Black Holes’, Tel Aviv, February 22, 2006Active Galactic Nuclei: From Atoms to Black Holes’, Tel Aviv, February 22, 2006
A Multiwavelength, A Multiwavelength, and extremely biasedand extremely biased View of Powerful High-Redshift AGNView of Powerful High-Redshift AGN
Ohad ShemmerOhad Shemmer
Penn State UniversityPenn State University
‘‘Active Galactic Nuclei: From Atoms to Black Holes’, Tel Aviv, February 22, 2006Active Galactic Nuclei: From Atoms to Black Holes’, Tel Aviv, February 22, 2006
Overall, similar SEDs and emission line properties.
What have we learned about distant AGN?
From the optical-near-IR: Barth+03
Fan+04
Similar RL/RQ fraction and overall SED.
What have we learned about distant AGN?
From the radio:Carilli+01
Stern+00 Low-z
High-z
No evolution in the X-ray spectral shape and intrinsic absorption.
What have we learned about distant AGN?
From the X-ray:
OS+05,06
OS+05
Distant SMBHs seem to feed and grow like local ones
Central engines of AGN are not aware of the cosmic epoch in which they live
Should investigate the full range of AGN physical properties, instead of focusing on evolution
The role of powerful AGN
Two related observational efforts:
1. Luminous AGN at z~2-3 with Hβ measurements
2. Multiwavelength properties of powerful AGN at z>4
0.52?
(The Hβ factory)
The starburst - ‘monster’ connection
Direct and indirect evidence for the coexistence of starbursts and ‘monsters’
Hamann & Ferland 99
Maiolino+05
Bertoldi+03
The metallicity-accretion rate relationship
Important implications for the starburst-‘monster’ connection.
OS, Netzer+04
Ham
ann &
Ferl
and 9
2, 93,
99
UV
- o
pti
cal
- near-
IR
The coexistence of starbursts and monsters
Evidence for starbursts in powerful, nearby and distant, AGN is piling up. [Are all of the above in conflict with [O II] (Ho 2005)?]
PI: R. Maiolino
PREL
IMIN
ARY
mid
-IR
Are there enormous NLRs?
Do powerful AGN blow off their NLRs? [Is this related to the luminosity-dependent obscuration, aka the ‘Steffen effect’?]
Netzer, OS+04
op
tica
l -
near-
IR(Netzer Line Region)
What determines the AGN SED?
Steffen+06 (yesterday’s astro-ph)
X-ray-to-optical spectral slope does not evolve and depends on UV luminosity. [Does αox depend primarily on the accretion rate?]
X-r
ay
- op
tica
l
13
Were AGN more X-ray variable in the past?
‘Typical’ long-term X-ray variability is detected in powerful AGN at high-z. No significant short timescale (~1 hr in the rest frame) variations are detected.
OS+05
X-
ray
14
Photon index measurements in luminous, high accretion rate sources are still missing.
OS, Brandt, Netzer+06
X-r
ay -
op
tica
l -
near-
IR
Is the photon index an accretion-rate indicator?
The next step: MBH & L/LEdd in the most distant powerful AGN
OS+06 (today’s astro-ph)
Measurements of Hβ at z>4 require L-band spectroscopy. [Should wait for JWST.]
X-
ray
Lineless quasars at high redshift: BL Lacs or a new type of unbeamed quasars?
OS+06 (astro-ph/0602442)
PI: X. FanPRELIMIN
ARY
The mystery deepens
Are powerful AGN analogous to NLS1s?
NLS1s Powerful AGN
?
?
High accretion rate High accretion rate
Super solar metallicitySuper solar metallicity
X-rays: steep spectral slope, extreme variations ?
?Evidence for recentstar formation
Hamann & Ferland 93, Dietrich+03
OS+04Boller+96, Crenshaw+03
OS & Netzer 02
Boller+96, Leighly 99
Moran+96
Conclusions
Thank you
Hagai