X-rays from the First Massive Black Holes

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X-rays from the First Massive Black Holes
Brandt, Vignali, Schneider, Alexander, Anderson,
Bassett, Bauer, Fan, Garmire, Gunn, Lehmer,
Lopez, Kaspi, Richards, Strateva, Strauss
Are early black holes feeding and growing in the
same way as local ones?
Chandra 4-10 ks snapshots (gt100) z gt 4.8 SDSS,
Opt. bright, RLQs, Exotic High detection
fraction ROSAT, Chandra, XMM-Newton archives
Additional z gt 4 detections Supporting samples
at z 0-4 Deep X-ray surveys
www.astro.psu.edu / users / niel / papers /
highz-xray-detected.dat
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X-ray Versus Optical Fluxes
X-ray and optical fluxes correlated. Fluxes
generally low X-ray spectroscopy challenging
even for XMM-Newton.
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X-ray Spectroscopy at z gt 4
XMM-Newton spectroscopy possible for a few of the
X-ray brightest quasars. Joint fitting can place
respectable average X-ray spectral constraints.
PSS 13260743 z 4.17 XMM-Newton
PSS 01210347 z 4.13 XMM-Newton
Also see Ferrero et al. (03), Grupe et al. (04)
Vignali et al. (2004)
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X-ray Spectral Comparisons at Low and High
Redshifts
Significant intrinsic scatter at all redshifts,
but no systematic trend. Inner-disk coronae
stable. No X-ray reflection humps detected.
No X-ray absorption detected.
Vignali et al. (03)
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X-ray Contribution to Spectral Energy Distribution
Combine high-redshift sample with well-defined,
lower-redshift samples to constrain X-ray
evolution. Want broad lum. and z coverage to
break degeneracies High-detection fraction
(pattern censoring issues) Reliable separation
of RQQ and RLQ Good BAL removal / control New
sample of 152 SDSS and PSS quasars spanning z
0.02-6.28
Partial correlation analyses indicate luminosity
effect is primary. No highly significant
trend with redshift.
Also see Vignali, Brandt, Schneider (2003)
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New X-ray Constraints on z gt 4 Radio-Loud Quasars
12 high-redshift RLQs with flat radio spectra and
moderate-to-high R. Fill X-ray observation
gap between RQQs and blazars. Representative of
majority of RLQs.
Bassett et al. (04)
Blazars
Lopez et al. (04)
New RLQ targets
100 detection rate with some bright objects
great for XMM-Newton.
Small-scale, jet-linked X-ray component (SSC)
consistent at z gt 4 and z 0. Degree of X-ray
enhancement vs. RQQs X-ray spectral
shape Suggestive evidence for X-ray absorption.
Radio quiet
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Rarity of X-ray Luminous Jets at z gt 4
One favored model for X-ray jet emission is
IC/CMB. Need bulk relativistic velocities on kpc
scales. If true, X-ray jets can outshine cores
at z gt 4.
Use Chandras imaging to search for such X-ray
luminous jets. We do not detect X-ray jets in
any of our 12 RLQs (including objects similar to
3C 273 and PKS 0637-752). Physical sizes lt
10-15 kpc. Such X-ray luminous jets are
rare. Perhaps synchrotron with multiple
electron populations?
Following Rees Setti (1968) etc.
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X-ray Survey Constraints on z gt 4 AGN
Probe moderate-luminosity, typical AGN at z gt
4 Minimize absorption bias (rest-frame 2-40 keV)
High-redshift sources and candidates in
central Chandra Deep Field-N
Find or constrain sky density exploiting Lyman
break. Alexander et al. (01), Barger et al.
(03), Cristiani et al. (04), Koekemoer et al.
(04) Constraints on reionization.
Vignali et al. (02)
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Ongoing Chandra and XMM-Newton Surveys
21 Ongoing Deep Surveys
18 Ongoing Wide Surveys
3.5 sq. degrees in total
Lists above available from astro-ph/0403646
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Constraining Lower Luminosity AGN at High Redshift
X-ray Stacking of Large Lyman Break Galaxy
Samples from GOODS
z 3.0
z 3.8
Lehmer et al. (04)
468 U-dropouts from GOODS-N Effective exposure
0.8 Gs 25 yr
338 B-dropouts from GOODS-N, S Effective
exposure 0.4 Gs 13 yr
Also tight constraints on V, i dropouts at z 5,
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Observed X-ray emission plausibly from X-ray
binaries and supernova remnants no need to
invoke numerous lower luminosity AGN.
Also see Moustakas Immler (04), Wang et al. (04)
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General Conclusions
AGN at z 4-6 and z 0-2 have reasonably
similar X-ray and broad-band spectra. No hints
of different accretion/growth mechanisms.
(After controlling for luminosity
effects) Small-scale X-ray emission
regions insensitive to strong large-scale environm
ental differences from z 0-6. X-ray emission
universal. X-ray surveys giving significant
demographic constraints on mod.-lum. AGN at
highest redshifts.
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Some Future Prospects
Improve coverage at z 5 - 6.5 Other
selection methods minimize bias IR, submm,
mm Minority populations Weak-line quasars,
BALQSOs, RLQs Better X-ray spectral and
variability studies
Chandra can go significantly deeper with best
positions for 20 years. Both Chandra and
XMM-Newton can go wider.
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Long-Term Prospects Proto-Quasars and Black
Holes from the First Stars
1 Chandra count per 35 yr