1. AMD Absorption Measure Distribution Evidence for Thermal Instability? By Tomer Holczer Cambridge, MA July 2007

2. Outline Interesting Questions about AGN outflows Absorption Measure Distribution analysis – The method Results Thermal Instability?

3. Some Interesting Questions Where is the wind? How close is it to the engine? Are there several absorbing components or a continuous distribution? Is the absorber in pressure equilibrium? Do thermal instabilities play a role?

4. Fig 1 : NGC 3783 flux – absorption lines from all charge states From neutral to H-like (5 orders in  )‏ The Data

5. Outflow Model : Method Determine continuum Identify absorption lines; determine outflow and broadening velocity Obtain column densities from data of each individual ion by fitting all its lines Reconstruct the Absorption Measure Distribution (as a function of  )‏ Fig 2 : IRAS 13349+2438 line profile of Fe +16 resonance at 15 Å (in black) and model in red. Fitting the broadening (width) and outflow (shift) velocity.

6. Absorption Measure Distribution, A New Method (analogous to emission measure distribution) Improvement on multi-component models AMD – Absorption Measure Distribution – is the gas column-density (N H ) distribution in ionization parameter ξ : AMD

7. Measuring N ion from HETG data Fig 3 : NGC 3783 (left panel), IRAS 13349+2438 (middle panel), and MCG -6-30-15 (right panel). spectra in black, model in red.

8. Iron ion fractional abundances NGC 3783 Fig 4: Iron ion’s relative abundances for NGC 3783 using XSTAR (Kallman & Krolik 1995)‏

9. Fig 5 : AMD of IRAS 13349+2438. The lower panel is the integrated column density. For IRAS 13349+2438 N H ~ 10 22 cm -2.

10. Abundance Ratios Compared to Sun

11. Fig 6 : AMD of NGC 7469. (Blustin et al. 2007). N H ~ 3 10 21 cm -2.

12. Fig 7 : AMD of NGC 3783. The cyan bins in NGC 3783 are the Krongold et al. model (with a bin width) and the green bins Netzer et al. model. N H ~ 4 10 22 cm -2.

13. Photo-ionized Plasma Models for NGC 3783 red squares represent the observed gap ION (Netzer et al. 2003)‏ XSTAR (Used by Holczer et al. 2007)‏ CLOUDY (Krongold et al. 2003)‏ TITAN (Goncalves et al. 2006)‏

14. Cooling Curves Cooling rates at different values of ξ/T (Krolik et al. 1981))

15. Conclusions All outflows in the AGN’s we’ve checked are missing gas at logT ~ 4.5 - 5 K We believe this is evidence for thermal instability in this region Observed unstable region is not produced exactly by codes Moreover, there are discrepancies between the different models

16. THE END

17. Fig 6 : Preliminary AMD of MCG -6-30-15. MCG -6-30- 15 have total column density around 7 10 21 cm -2.

18. 2±0.5 1.2±0.3 1.7±0.7 0.7±0.2 3.7±2 MCG -6-15-30 (A z /A Fe )/ (A z /A Fe ) O 0.7 ±0.78.71 ±1.41Carbon 4.3±2.68.38 ±5.620.6±0.52.14±0.38Nitrogen 1.9±0.42.3±0.811±91.15±0.17Silicon 1.0 ±0.36±5.50.49±0.08Sulfur 1.5 ±0.51.4±0.51.0±0.91.20±0.29Magnesium 1.9 ±0.630±201.20±0.29Sodium 1.4±0.51.3 ±0.83.0±1.32.64±0.44Neon 1.0±0.21.3 ±0.5 2.64±16.2 2 Oxygen NGC 3783 (A z /A Fe )/ (A z /A Fe ) O IRAS 13349+243 8 (A z /A Fe )/ (A z /A Fe ) O NGC 7469 (A z /A Fe )/ (A z /A Fe ) O Sun Ratios (A z /A Fe ) O from Asplund et al. 2005 Element