High Resolution Soft Xray Spectroscopy of AGN

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High Resolution Soft X-ray Spectroscopy of AGN
G. Branduardi-Raymont, A. Blustin, M. J. Page
(UCL-MSSL)
EDGE workshop, Rome, 19 21 December 2006
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The power of X-ray spectroscopy

• 0.2 10 keV band rich in discrete spectral
  features
• K-shell transitions of C, N, O, Ne, Mg, Si, S,
  Ca
• L- and K-shell transitions of Fe
• All charge states visible in single X-ray
  spectrum ?
• essentially un-ambiguous interpretation
• Powerful diagnostics of physical conditions of
  the source
• dynamics, elemental abundances, ionisation
  states,
• temperatures, densities, nature of the emission
  
• and absorption processes
• Particular emphasis on AGN in the soft X-ray band

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What are AGN warm absorbers?

• Outflows of ionised gas from AGN
• Studied using soft X-ray and UV absorption
  features
• Moving at speeds of hundreds to thousands of
  kilometres
• per second
• Absorbing columns of 1021 1023 cm-2
• Wide range of ionisation Log x 0.3 3

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Warm absorbers at high resolution
XMM-Newton RGS
Absorption lines due to multiple ionisation
states of iron, neon and oxygen
Measure outflow speed, amount of gas, how highly
ionised it is, elemental composition
data model
Blustin et al. 2006, submitted
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Emission lines and density estimation
M81

• He-like OVII
• G (xyz)/w ratio used to establish the
  ionisation mechanism
• (G gt 4, pure photoionisation)
• Large R z/(xy) ratio implies nelt 109 cm-3

phot.
coll.
ne lt 1011cm-3
Page et al. 2003, AA, 400, 145
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X-ray broad emission lines
Mrk 509

• Broad OVII(r) and CVI Lya
• Likely to arise in the BLR
• (8700 and 7100 km s-1)
• Similar broad X-ray lines observed in NGC5548
  (Steenbrugge et al. 2005), Mrk 279 (Costantini et
  al. 2005) and 3C273 (Page et al. 2007)

Smith et al. 2007, in press
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The nature and origins of warm absorbers

• Surveyed the results of high resolution X-ray
  spectroscopy of 23 individual Seyfert-type AGN
  (Blustin et al. 2005, AA 431 111) and found
  that
• The outflows are likely to originate from the
  dusty torus and
• have a low volume filling factor (lt10)
• The energy they carry is lt1 of the AGN
  bolometric
• luminosity BUT the mass outflow rate is often
  greater than
• the mass accretion rate powering the AGN
• Over an AGN lifetime, the outflow rate is
  sufficient to
• supply, e.g. all the hot ISM in a Seyfert
  galaxy bulge

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The big question
Are warm absorbers weather or climate? H.
Netzer, 2001
Is this phenomenon purely incidental, or is it
telling us something fundamental about the way
AGN work?
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New black hole in star forming clouds
Black hole/galaxy co-evolution
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New black hole in star forming clouds
Black hole grows, stars form
Black hole/galaxy co-evolution
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New black hole in star forming clouds
Energy output blasts away gas clouds, stopping
star formation
Black hole grows, stars form
Black hole/galaxy co-evolution
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New black hole in star forming clouds
Energy output blasts away gas clouds, stopping
star formation
Black hole grows, stars form
Black hole/galaxy co-evolution
Black hole accretes remaining gas unobscured
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New black hole in star forming clouds
Energy output blasts away gas clouds, stopping
star formation
Black hole grows, stars form
Black hole/galaxy co-evolution
Black hole accretes remaining gas unobscured
Silk Rees 1998, Fabian 1999, Granato et al.
2004, Page et al. 2004
Dormant black hole, fuel used up
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A glorious future for warm absorbers

• There is increasing observational evidence for
  this evolutionary scheme
• The hosts of certain X-ray absorbed quasars are
  at
• the transition between massive star formation
  and
• quiescent elliptical stellar population (e.g.
  Page et al.
• 2004 ApJ 611 85, Stevens et al. 2005 MNRAS 360
  
• 610)
• The absorption is caused by a massive outflow
  (Page
• et al. 2006, ESA SP-604, 646)

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Requirements for future missions

• High resolution soft X-ray spectroscopy of these
  outflows
• has a big contribution to make to a (the?)
  major remaining
• puzzle in cosmology
• This is prime EDGE science
• A combination of high resolution, effective area
  and low
• background is required to probe the outflows in
  distant
• AGN, especially in the soft X-ray band
• Associated with low ionisation absorbers are
  often high
• ionisation phases at high column densities
  which imprint
• signatures in the hard X-ray band

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XMM-Newton RGS vs EDGE LET/TES
Blustin et al. 2006, submitted
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Now, slight change of subject
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Jupiter X-ray science with XMM-Newton (EPIC)
Jupiters auroral X-rays 0.3 2 keV Ionic
charge exchange gt 2 keV Electron
bremsstrahlung (kT 50 keV)
? connection with
magnetosphere/solar wind Low-latitude disk
X-rays Scattering of solar X-rays in Jupiters
atmosphere Emissions are
variable and relate to solar activity
Jupiters auroral and disk spectra
Jupiters auroral maps
Ion charge exchange
Electron bremsstrahlung
Branduardi-Raymont et al. 2006, AA, in press
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XMM-Newton RGS
Jupiter
FeXVII
OVII
OVIII
RGS clearly resolves the emission lines
dominating in soft X-rays and separates
spectrally auroral and disk components
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Jupiter
RGS
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Jupiter
RGS
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Jupiter
RGS
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X-ray spectroscopy of Jupiter with EDGE

• High spectral resolution of LET/TES can resolve
  ion species and establish origin of heavy ions
  leading to auroral X-ray emission
• HET spectra can characterise the electron
  bremsstrahlung component in the aurorae
• Investigations of auroral X-ray dependence on
  magnetospheric and solar wind conditions ?
  diagnostics of Jovian magnetospheric physics
• Study dependence of Jovian disk X-rays on solar
  activity

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Thank you