1. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Accretion Disk Atmospheres Mario Jimenez-Garate MIT John Raymond CfA Duane Liedahl LLNL Christopher Mauche LLNL

2. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Part I: Accretion Disk Atmospheres in X-ray Binaries EXO 0748-676 4U1626-67 Rendering code by R. Hynes Hercules X-1

3. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Hercules X-1 in the Low State

4. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Physical Model of Centrally Illuminated Accretion Disk Atmosphere Radiation Transfer Gravity Hydrostatic Equilibrium Thermal Balance Ionization Equilibrium L X = 10 37.3, 10 38.3 erg s -1 M NS = 1.4 M SUN Continuum is 8 keV bremsstrahlung. Solar abundances 10 8.5 < r < 10 11 cm =

5. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Radiation Transfer Gravity Hydrostatic Equilibrium Thermal Balance Ionization Equilibrium Compton heating + photoionization heating = Compton cooling + recombination cooling + bremsstrahlung cooling Ionization rate = Recombination rate Semi-Newtonian disk flux output (Shakura & Sunyaev 1973, Agol & Krolik 2000) · Model for Accretion Disk Atmosphere Structure

6. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Temperature and Ionization Structure of Disk Atmosphere and Corona Vertical Ionization Structure Atmosphere is thickened by Irradiation Irradiation -Atmosphere Feedback

7. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Simulated Spectra of a Centrally-Illuminated X-ray Atmosphere and Corona for a Low-Mass X-ray Binary

8. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Spectroscopic comparison with an Illuminated Accretion Disk Atmosphere and Corona Model Parameters: L = 3x10 37 erg/s (constrained) disk radii = 10 10.9 < r < 10 11 cm (fitted)

9. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Spectroscopic comparison with an Illuminated Accretion Disk Atmosphere and Corona Model Temperature Diagnostics The RRCs indicate Ne IX RRC yields kT = 7 ± 3 eV (T = 81000 ± 35000 K) photoionization. Ly  /Ly  ratios The Ly  Ly  ratios are Ion Observed Model line optical depth diagnostics. Mg XII 2.9 ± 0.9 4.8 Ne X 4.5 ± 1.2 3.3 O VIII 14 ± 6 4.7

10. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Fe I-XIII and Fe XXVI emission lines in Hercules X-1 - Bright Fe fluorescence from near-neutral gas (Fe I-XIII) - Fe XXVI from hot corona. Fe K  /Fe K  = 6.2 ± 1.6 (7.99 for Fe I, from Kaastra & Mewe 1993) Fe K    Fe K   = 2.28 ± 0.45 (2.00 for Fe I, idem)

11. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) For LMXB dippers, the Soft X-ray Band is dominated by the Disk Atmospheric Emission Comparison with Spectral Data Model Data EXO 0748-676: eclipses, bursts, dips P orb = 3.8 hr, M 2 ~ 0.4-0.8 M sun

12. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Part II: Accretion Disk Atmospheres near Supermassive Black Holes XMM-Newton EPIC observation of MCG-6-30-15, Fabian et al. (2002) How do we interpret line emission?

13. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Radiation transfer and vertical structure of disk annulus

14. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Time-averaged temperature structure of accretion disk Corona Atmosphere Optically thick disk M = 10 24 g/s  = 2.1 E max = 150 keV f = 1 M = 10 7 M sun a = 0.998 ·

15. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Time-averaged density structure of accretion disk Corona Atmosphere Optically thick disk

16. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Modeled disk atmosphere x-ray line spectra Comoving disk frame Observer frame

17. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Line emission from the accretion disk atmosphere and corona of a supermassive Kerr black hole O VII N VII O VIII Ly  Fe K C VI N VI O VII RRC C V O VIII +Ne IX blend Model-dependent X-ray EW is 98 to 188 eV Compton broadening and line transfer not included here A 150 keV cutoff and MCG-6-30-15 like parameters were used to obtain 'maximal' soft x-ray emission

18. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Comparison of Model with Seyfert I X-ray Spectra Controversy: Lee et al. (2001) interpret only dusty warm absorber in these AGN. Branduardi-Raymont et al. (2001)  =2.1, Low Accretion Rate (0.3)  =1.9, High Accretion Rate (5.0) Model Disk Atmosphere for Kerr Black Hole Disk

19. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Representative line emissivities from recombination and fluorescence The emissivity functions roughly scale like the ionizing continuum Input continuum

20. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Monte Carlo: X-ray emission lines are converted to other Lyα lines within the atmosphere Seed Line: O VIII Ly  at E 0 = 0.67 keV High probability of escape Seed Line: Ne X Ly  at E 0 = 1.0 keV Conversion to O VIII and C VI Mauche et al. (2004)

21. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Monte Carlo: Composite X-ray spectrum of H-like and He-like ions Line transfer effects off Line transfer effects on (recombination follows photoabsorption) Mauche et al. (2004.)

22. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) The soft x-ray line intensity is sensitive to the ionizing spectrum  =1.9, Ecut = 150 keV Ebins < 1 MeV.  = 2.1, Ecut = 150 keV E bins < 100 keV.

23. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Accretion Disk Atmosphere Models: Conclusions Agreement of disk atmosphere models with X-ray Binary X-ray spectra & DEM. Model predicts line fluxes; illuminated disk area derived. Measured densities and temperatures agree with model. Explained presence of lines in only high-inclination systems. TBD: comptonized continuum, instability signatures, He-like ion layer. Relativistically-broadened line complex has characteristic sawtooth shape in soft X- rays: O VII, O VIII, C VI, C V, N VII, and N VI. Monte Carlo: optical depth affects spectrum. Predict anti-correlation between Fe K fluorescence and recombination line intensities. Line emissivities scale with local disk energetics, except for Fe XXVI/Fe XXV, for which emissivity index= 4. EWs not definitive due to model assumptions. TBD: MHD dynamics, full MC line transfer, Fe L K-shell fluorescence.

24. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Monte Carlo: X-ray RRC photons are converted to Ly  lines within the atmosphere Seed photons: O VIII RRC  at E 0 = 0.86 keV Conversion to O VIII Ly  and C VI Ly  Seed photons: Ne X RRC at E 0 = 1.3 keV Conversion to O VIII Ly  and C VI Ly 

25. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Model prediction: the anti-correlation of the fluorescence and the recombination line fluxes The intermediate layer that produces the recombination emission absorbs some of the photons which produce the Fe K fluorescence line at the bottom layer.

26. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Strong Theoretical Evidence for Accretion Disk Atmosphere and Corona present in 0.01-1L edd neutron star LMXBs X-ray Spectroscopic data reveal high density photoionized medium in LMXBs Verified via Optical Depth and Plasma Diagnostics of T e,n e Thickened by Irradiation and Feedback High Inclination LMXBs have largest line EW's Lines in LMXBs produced by outer disk, inner disk, or disk warp. Weak Coupling with Shakura & Sunyaev Disk Disk Atmospheres in X-ray Binaries: Conclusions Lines of the H-like ions from Fe to C are matched Multiple LMXBs show atmosphere signature, disk radii derived Thermal stability and disk structure will start to be diagnosed

27. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) 3D Monte Carlo code tracks the complex interactions and trajectories of individual photons S S E Photon destroyed Photon escapes radius  z  Colors encode the relative energy of the photon, starting (S) with purple and ending (E) with red.

28. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Accretion Disk Atmospheres in X-ray Binaries: Observations EXO 0748-676 4U1626-67 Used rendering code by R. Hynes Hercules X-1

29. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Physical assumptions of 2-stage spectral model atmosphere Self-illuminated Disk Hydrostatic Equilibrium Thermal Balance (non-LTE) Photoionization Equilibrium Gas-pressure supported disk interior from Page & Thorne (1974) Low-res, 2D radiation transfer 2 )Monte Carlo Radiation Transfer 3-dimensional (4D IP) Compton scattering, Klein-Nishina Continuum opacity Recombination & Fluorescence Line transfer effects 2) Semi-analytic Radiation Transfer 2+1 dimensional Thomson Scattering Continuum opacity Recombination & Fluorescence Use Cunningham (1975) & Laor (1991) GR raytraces for line profiles 1) Structure (time avg.) Riffert & Herold (1995)

30. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Input parameters and calculation of 2+1 dimensional disk structure Jimenez-Garate, Raymond, Liedahl, & Hailey (2001, ApJ, 558, 448) Jimenez-Garate, Raymond, & Liedahl (2002, ApJ, 581, 1297) B H parameters: mass (10 7 M o ), spin (a=0.998) Free parameters: inner disk torque (nonzero), powerlaw-to-thermal energy ratio, powerlaw illumination geometry i = 30  = 0.01

31. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Density and Location Diagnostics for Hercules X-1 (w/Chandra) X

32. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) In the Dipper LMXBs, the Neutron Star X-rays are Partially Absorbed Comparison with Spectral Data Model HETG Data (EXO 0748-676) Dips vs. No Dip Dips

33. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Conversion of X-ray emission lines is a consequence of continuum opacity and ionization balance Photons above the photoelectric absorption edge of an abundant ion are converted efficiently

34. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Have We Detected Soft X-ray Lines Emitted by the Accretion Disk Close to the Black Hole? Branduardi-Raymont et al. (2001) Sako et al. (2003) Chandra HETGS spectrum of MCG-6-30-15 Lee et al. (2001) Turner et al. (astro-ph/0303418) YES NO

35. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Comparison of the Soft X-ray Emission from Accretion Disk Atmosphere Models (Kerr) Unlike our model, the B&F (2002) model is calculated at a single radius and extrapolated to the rest of the disk via a power-law parameterization.  =2.1, Low Accretion Rate (0.3) Our model (semi-analytic) Ballantyne & Fabian (2002)

36. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Comparison of X-ray Emission from Accretion Disk Atmosphere Models Nayakshin & Kallman (2001) Ballantyne & Fabian (2002) Our Model

37. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) The challenge: to model the atomic processes which determine the disk atmosphere spectrum RRC

38. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Low Mass X-ray Binaries with Broad Emission Lines EXO 0748-676 : eclipses, bursts, dips P orb = 3.8 hr, M 2 ~ 0.4-0.8 M sun, i ~75° 4U1626-67 : X-ray pulsar: disk disturbed by B field P orb = 42 min, M 2 = 0.02-0.08 M sun, i ~30° HETGS Schulz et al.(2001) HETGS Jimenez-Garate et al. (2002)

39. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Accretion disk atmosphere structure Radiation pressure on Radiation pressure off (chosen) Warm corona Recombination layer Fluorescence layer

40. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Thermal instability in photoionized plasma Warm corona Recombination layer Fluorescence layer Nayakshin & Kallman (2001) Plotted vs. F X /F bb

41. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Comparison of Model with Seyfert I X-ray Spectra Ogle et al. (2004) fit soft excess with broad O VIII emission complex. Ogle et al. (astro-ph/0401173)  =2.1, Low Accretion Rate (0.3)  =1.9, High Accretion Rate (5.0) Model Disk Atmosphere for Kerr Black Hole Disk

42. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Line Emission from Disk Atmosphere and Corona, plus Continuum from Neutron Star Synthetic X-ray Spectrum vs. Absorption N H of Neutron Star Flux

43. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Photoionized Plasmas in Thermal and Ionization Balance (non-LTE) Particle-photon interactions Heating = Cooling Recombination rate = Photoionization rate  Ionization parameter Emission measure Recombination Line luminosity

44. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) The Spectrum of a Disk Atmosphere and Corona depends Strongly on Viewing Angle Exception: X-ray pulsars can exhibit lines at low inclination Photosphere

45. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Part III: Supporting Slides

46. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Thermal instability in photoionized plasma Warm corona Recombination layer Fluorescence layer Nayakshin & Kallman (2001) Plotted vs. F X /F bb

47. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate(MIT) Thermal instability in photoionized plasma Warm corona Recombination layer Fluorescence layer

48. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Spectroscopic comparison with an Illuminated Accretion Disk Atmosphere and Corona Model The under-prediction of the He-like ion fluxes suggests the suppression of a thermal instability. The model shows a Nitrogen over- abundance, confirming XMM-Newton RGS (Jimenez-Garate 2002). Velocity broadening OVIII  (12 mÅ):  300 km/s expected)

49. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Centrally Illuminated Accretion Disk A Thick Atmosphere and Corona

50. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) The line profiles probe the structure and radius of the disk atmosphere Synthetic profiles used to derive 10 8.5 < r < 10 11 cm “inner and outer” disk HETG Data (EXO 0748-676)

51. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Low Mass X-ray Binaries with Narrow Emission Lines Hercules X-1 X-Ray Pulsar P orb = 40.8 hr i ~ 85° (Jimenez-Garate et al. 2002). 4U1822-37 ADC source P orb = 5.57 hr i ~ 75-85° HETGS Cottam et al. (2001). Also ADC sources - 2S 0921-63 (Kallman et al. 2003), - AC211 (White et al. 2002)

52. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) In the Dipper LMXBs, the Neutron Star X-rays are Partially Absorbed Comparison with Spectral Data Model HETG Data (EXO 0748-676) Dips vs. No Dip

53. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) Cottam et al. (2001) MEG HEG MEG / 50 ks simulation ADC Sources Show Emission from the Outer Radii of the Disk only Narrow Line Emission from a Disk Bulge in 4U 1822-37: X-ray pulsar, ADC, P orb = 5.6 hr Comparison with Spectral Data

54. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) The Low and Short on States of Hercules X-1 show emission lines and a weak continuum XMM-Newton RGS spectra Jimenez-Garate et al. (2002)

55. Accretion Disk Atmospheres 2004 Mario Jimenez-Garate (MIT) The He-like ion line ratios constrain the electron density and UV field For Hercules X-1, we diagnose d and the electron density. 2 3 S 1 -> 2 3 P 0,1,2 wavelengths: O VII 1637 Å Ne IX 1270 Å Mg XI 1033 Å Si XIII 864 Å Used Porquet & Dubau (2000) calculations for n e. d < 3 x 10 12 cm n e > 8 x 10 11 cm -3 d < 7 x 10 11 cm n e > 8 x 10 12 cm -3 D ~ 2.4 x 10 11 cm n e = (2.2 ± 0.8) x 10 13 cm -3 No d limit (due to Lyman  edge) n e < 1.1 x 10 13 cm -3