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High Resolution Soft Xray Spectroscopy of AGN

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XMM-Newton RGS. Emission lines and density estimation. He-like OVII ... Jupiter X-ray science with XMM-Newton (EPIC) Jupiter's auroral maps ... – PowerPoint PPT presentation

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Title: High Resolution Soft Xray Spectroscopy of AGN


1
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
2
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

3
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

4
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
5
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
6
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
7
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

8
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?
9
New black hole in star forming clouds
Black hole/galaxy co-evolution
10
New black hole in star forming clouds
Black hole grows, stars form
Black hole/galaxy co-evolution
11
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
12
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
13
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
14
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)

15
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

16
XMM-Newton RGS vs EDGE LET/TES
Blustin et al. 2006, submitted
17
Now, slight change of subject
18
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
19
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
20
Jupiter
RGS
21
Jupiter
RGS
22
Jupiter
RGS
23
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

24
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