The mass-energy budget of the ionised outflow in NGC 7469
Sponsored Links
This presentation is the property of its rightful owner.
1 / 18

The mass-energy budget of the ionised outflow in NGC 7469 PowerPoint PPT Presentation


  • 90 Views
  • Uploaded on
  • Presentation posted in: General

The mass-energy budget of the ionised outflow in NGC 7469. Alexander J. Blustin. STFC Postdoctoral Fellow, UCL Mullard Space Science Laboratory.

Download Presentation

The mass-energy budget of the ionised outflow in NGC 7469

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


The mass-energy budget of the ionised outflow in NGC 7469

Alexander J. Blustin

STFC Postdoctoral Fellow, UCL Mullard Space Science Laboratory

In collaboration with G. Kriss (STSCI), T. Holczer (Technion), E. Behar (Technion), J. Kaastra (SRON), M. Page (UCL-MSSL), S. Kaspi (Tel-Aviv), G. Branduardi-Raymont (UCL-MSSL), K. Steenbrugge (Oxford)

Chandra X-ray Gratings Meeting, Cambridge, MA, 11th July 2007


UV absorption – less ionised

Kriss, Blustin et al. 2003, A&A 403, 473

What is the total mass-energy output through an AGN wind?

How biased is this by the waveband in which we do the spectroscopy?

X-ray absorption – more ionised

Blustin et al. 2007, 466, 107

ionised wind

Artist’s impression of ionised wind in nuclear region of a galaxy (A. Blustin)


Blustin et al. 2007, A&A 466, 107

Dataset and spectral continuum

  • NGC 7469 (z = 0.0164) is an X-ray and UV bright Seyfert with a low-column warm absorber

  • 164 ks with XMM-Newton, obtained in Nov/Dec 2004

  • Highest signal-to-noise X-ray grating and CCD spectra yet obtained for this source

Basic form of spectral continuum obtained from EPIC-pn: power-law (G = 1.81) plus soft excess (we used a 0.144 keV blackbody component). Significant soft X-ray residuals are visible


The X-ray absorption and emission features

Blustin et al. 2007, A&A 466, 107

Significance of narrow spectral features

Dc2 = 16 implies 4s significance


Fitting individual ionic columns

Blustin et al. 2007, A&A 466, 107

Ion-by-ion (slab in SPEX) absorber model superimposed on RGS data

Individual ion columns


Absorption Measure Distribution (AMD)

The AMD expresses the total line-of-sight column density as an integral over its distribution in log x

NHtotal = (3.3 ± 0.8) x 1021 cm-2

Blustin et al. 2007, A&A 466, 107

Two main ionisation regimes: most gas at higher levels of ionisation

See talk by Tomer Holczer for more details on AMDs


Photoionised absorber modelling

Blustin et al. 2007, A&A 466, 107

Scott et al. 2005 SED for Chandra/FUSE data

Blustin et al. 2007 SED for XMM-Newton data

Spectral Energy Distribution (SED) used to calculate SPEX xabs photoionised absorber model has PN spectral slope, and is normalised using fluxes from RGS and OM


Photoionised absorber modelling

3 absorber components:

X-ray 1

X-ray 2

X-ray 3

Log x = 0.8+0.4-0.3

Log NH = 19.5 ± 0.2 cm-2

v = -2300 ± 200 km s-1

Log x = 2.73 ± 0.03

Log NH = 21.30+0.04-0.05 cm-2

v = -720 ± 50 km s-1

Log x = 3.56+0.08-0.07

Log NH = 21.5 ± 0.1 cm-2

v = -580+80-50 km s-1

Blustin et al. 2007, A&A 466, 107


Velocity components in the X-ray absorber


UV properties from

Scott et al. 2005

Comparison with UV-absorbing outflow

Ionic columns (1014 cm-2)

Log x

v (km/s)

NCIV

NNV

NHI

UV 11.61562 ± 60.98 ± 0.092.9 ± 0.87 ± 2

UV20.511901 ± 62.0 ± 0.12.5 ± 0.22.4 ±0.5

X-ray 10.8+0.4-0.32300 ± 2001.63.46.2

X-ray 22.73 ± 0.03720 ± 50n/a0.00091n/a

X-ray 33.56+0.08-0.07580+80-50n/an/an/a


UV properties from

Scott et al. 2005

Comparison with UV-absorbing outflow

Ionic columns (1014 cm-2)

Log x

v (km/s)

NCIV

NNV

NHI

UV 11.61562 ± 60.98 ± 0.092.9 ± 0.87 ± 2

UV20.511901 ± 62.0 ± 0.12.5 ± 0.22.4 ±0.5

X-ray 10.8+0.4-0.32300 ± 2001.63.46.2

X-ray 22.73 ± 0.03720 ± 50n/a0.00091n/a

X-ray 33.56+0.08-0.07580+80-50n/an/an/a

Identify UV component 2 with X-ray component 1


The location of the soft X-ray/UV absorbing outflow

Distance estimates:

Rmin from escape velocity

Rmax from DR/R ≤ 1

Outflow component

Blustin et al. 2007, A&A 466, 107


Momentum of outflowing matter

Momentum of radiation absorbed and scattered by wind

~

Calculating the mass and energy transport of the outflow

.

1.23 mproton Lion Cv v W

Mass outflow rate, Mout ~

x

Volume filling factor of the outflow obtained from the assumption that, for a radiatively driven wind:

Blustin et al. 2005, A&A 431, 111


.

1

Mout v2

2

Calculating the mass and energy transport of the outflow

.

1.23 mproton Lion Cv v W

Mass outflow rate, Mout ~

x

(Labs + Lscatt) x

Volume filling factor, Cv ~

1.23 mproton c Lion v2W

Kinetic luminosity, LKEout =

Blustin et al. 2005, A&A 431, 111


The mass-energy output of NGC 7469

Mass outflow rate

(Solar masses per year)

Log Kinetic Luminosity

(erg s-1)

X-ray component 10.00239.6

X-ray component 20.0339.7

X-ray component 30.0239.4

UV component 10.00638.7

UV component 20.000438.7


The mass-energy output of NGC 7469

Mass outflow rate

(Solar masses per year)

Log Kinetic Luminosity

(erg s-1)

X-ray component 10.00239.6

X-ray component 20.0339.7

X-ray component 30.0239.4

UV component 10.00638.7

UV component 20.000438.7

The same gas


The mass-energy output of NGC 7469

Mass outflow rate

(Solar masses per year)

Log Kinetic Luminosity

(erg s-1)

X-ray component 10.00239.6

X-ray component 20.0339.7

X-ray component 30.0239.4

UV component 10.00638.7

UV component 20.000438.7

Total0.0640.1

The same gas

Using the X-ray phase properties for X1/UV2


Conclusions

  • We estimate that ~90% of the mass outflow rate and ~95% of the kinetic luminosity are associated with the soft X-ray absorbing components in this object.

  • For a complete picture, we would also want to look at the highest-ionisation gas absorbing above 6 keV.

  • Is this also the case for distant X-ray faint AGN (e.g. BALQSOs) for which we can only do optical spectroscopy? This has implications for attempts to infer the mass-energy output of cosmologically-interesting AGN winds from their rest-frame UV spectra.

For further details see Blustin et al. 2007, A&A 466, 107


  • Login