1. 1 X-ray Diagnostics of Physical Conditions in Warm Absorbers Y. Krongold (UNAM) N. Brickhouse (CfA) M. Elvis (CfA) F. Nicastro (CfA) S. Mathur (Ohio State U.) D. Liedahl (LLNL)

2. 2  Found in the X-ray and UV spectra of 1/2 of all Seyfert 1 galaxies  Blueshifted (500-1000 km s -1 )  winds  m OUT  m accr  dynamically important Valuable to understand quasars Interaction with ISM Metal pollution of the IGM Warm Absorbers

3. 3 NGC 3783  Bright Seyfert galaxy redshift 0.0097 (2926 km s-1)  Extensively observed in the X-rays Monitored by the Chandra HETGS, Total exposure of 900 ksec > 2000 counts per resolution element at 7 A

4. 4 NGC 3783 Chandra MEG 900 ksec exposure 1keV

5. 5 Modeling with PHASE  Based on APED (Smith et al. 2001)  accuracy in the wavelength  Plus data for inner shell transitions (Behar et al. 2001, 2002), and from Verner list  Ionization balance from CLOUDY  Includes a Voigt Profiles  Self Consistent Model  Global Fit

6. 6 NGC 3783 Model  Photoionization Equilibrium Models  3 Free parameters per absorption component: U =Q/4  cr 2 n Ionization Parameter N H Column Density V OUT Outflow Velocity  2 Absorption Components

7. 7 NGC 3783 Chandra MEG 900 ksec exposure 1keV

8. 8 NGC 3783 Chandra MEG 900 ksec exposure

9. 9 Model Highlights  Simple solution  only 2 absorbing components (LIP and HIP)  Fits more than 100 features with only 6 free parameters.  Predicts reasonable absorption in the UV by the LIP  Netzer et al. (2003) modeled a third hotter component (Fe K-shell, VHIP)

10. 10 Does not fit two significant LIP lines: Si X, Si XI  Lack of low temperature (n=0) DR rates for Fe M-shell (Netzer et al. 2003; Netzer 2004; Kraemer Ferland and Gabel 2004) Si X-XI

11. 11 Other Representation  Many Charge states present in the spectrum  Continuous Radial Flow of Ionization structures Several charge states of the same element are significantly present  Not a global fit, but based on ion by ion Fits everything 40 free parameters Not self consistent

12. 12  Pressure Equilibrium  Similar kinematical properties  Confirmed by Netzer et al. (2003), plus 3erd component  3 phase medium Phases of the same medium:  1/P

13. 13 Another Case of Pressure Balance: NGC 985  Pressure Equilibrium  Similar kinematical properties  Marginal evidence of 3rd component  3 phase medium?  1/P Krongold et al. 2004, ApJ in press 80ksec exposure with Chandra HETGS

14. 14 Constraining the Structure and Location of the Absorber

15. 15 Constraining the Structure of the Absorber Continuous Flow  Several Charge States of the same element  Averaged absorption is observed  No response to flux variations by factors < 3-5 Clumped Gas  Should respond even to moderate flux variations  Isolated Components  vary as expected in PI   U   Flux  Opacity variation in response to flux variations

16. 16 Variability on NGC 3783 (LIP) Bin size of 0.25 Å DataPhotoionization Equilibrium Model Krongold et al. 2005, ApJ in press 2X flux increase

17. 17 The UTA varies as expected in PI Data Ratio Model Ratio Significance ~10

18. 18 Implications of Variability  Variability observed in the UTA  rules out a Radial Continuous Flow of Ionization Stages  If LIP in PI Using t obs as upper limit to recombination time  n e  10 4 cm -3 Using n e and U1/n e D 2  D < 6 pc (Reeves et al. 2004; Nicastro et al 1999; Netzer et al. 2002; Kriss and Blustin et al. 2003, Kaastra et al.2004) ΔD <.15 pc  Compact Absorber  Behar et al. (2003) D > 2 pc

19. 19 Further Constraints of the Density  Most Determinations are Upper or Lower Limits  We need to constrain the density n e to constrain D  Diagnostics of n:  Atomic Physics (Kaastra 2004)  Time Evolving Photoionization Models (Nicastro 1999)

20. 20 Constraining the Line Widths of the Absorber Constraining the Geometry?

21. 21 The width of the Lines  Absorption Lines are not Resolved  We have to constrain the width of the Lines indirectly  Through Models (Widths > 200 km s -1 )  Through UV data (Widths between 100-200 km s -1 )

22. 22 Voigt Profiles  Convolution of Natural and Doppler Broadening  Voigt Parameter a  Γ/Δ  Not relevant in other bands a << 1  Relevant in X-rays a > 1 (Inner shell Transitions)  Affects the Depth at the core of the line:  o N i f ul  o

23. 23  o N i f ul  o Fe Inner Shell vs. Outer Shell

24. 24 Constraining the Geometry UV data Constraints (Figure by Arav 2003) UV widths >> X-ray widthsUV widths ~ X-ray widths UV X-ray Constraining the widths we can constrain the angle of the flow Transverse Flow

25. 25 Conclusions  WA can be modeled with a Simple picture Fits almost all absorption features with only few free parameters  3 or 2 phases  Observed in other objects (NGC 5548, Kaastra et al 2002; IRAS 13349+2438, Sako et al. 2001, etc.) Intrinsic property related to the structure of the nuclear environment of AGN  Pressure equilibrium (and similar kinematics) Suggests pressure confinement  Observed Variability Rules out a Radial Continuous flow  clumped gas  Better Diagnostics in n e and D  Better Diagnostics of the widths  Geometry  Consistent with transverse flow (consistent with UV observations)

26. 26 Fe XVII-XXI does NOT vary simply (as expected in PI at constant density) Variability on NGC 3783 (HIP)

27. 27

28. 28 Fe Inner Shell Si Complex between 6-7 A Inner Shell Transitions Outer Shell

29. 29 Implications  Observed variability in the absorbing components is consistent with variation at constant pressure in a PI multi-phase wind  3 phase medium  Change in constant pressure  t Pgas < t PI  Fragmentation of the absorber in cloudlets (as suggested by the UV obs, Gabel et al. 2003)

30. 30  LIP (Fe VII-XII) vary as expected in PI  HIP (Fe XVII-XXI) does not vary simply  VHIP (Fe XXIV-XXVI) vary as expected in PI (Reeves et al. 2004)  The HIP could be out of PI (Time evolving effects)  different location than that of the LIP and the VHIP  An scenario of pressure confinement can also explain the observed variation of the 3 components. Variation in Pressure Balance and PI

31. 31 BeppoSAX BeppoSAX data of NGC 985  1/P 3X flux increase  1/P Krongold et al. 2004 Variation of HIP in PI and const. n e Chandra VHIP

32. 32 Observational limitations UV spectra have 20 times better spectral resolution Difficult component identifications Lack of simultaneous observations The UV/X-ray connection is uncertain:

33. 33

34. 34

35. 35 Fe Inner Shell

36. 36