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X-ray diagnostics with full radiative transfer (ALI method) Loic Chevallier, Anne-Marie Dumont, Olivier Godet, Suzy Collin, Anabela C. Goncalves
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ALI method Gives I(z, , ) : 1% Fast iterative method, Max. accuracy : z, -grid. PRD, polarization, multi-D, etc. Escape probability : requires homogeneous medium optically thin at the line frequencies, no energy balance. 2-stream : 1 angle GS/SOR > x10 faster Quang, Paletou, Chevallier, 2004
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TITAN code Photoionized non-LTE medium Plane-parallel geometry Gives consistent T, pops., flux (outward, reflected) in all directions Local and global radiative equilibrium Modes : constant density, gaseous pressure, total pressure 102 ions, microturbulence Compton heating (NOAR) He-like : 15 levels + continuum (Godet et al., A&A 2004) Accuracy order 10 % for the triplet Previous 11 levels model : 50 % accuracy (Coupé et al., A&A 2004) log CD < 26 5 < log n H < 14 1 < log < 4 4 < log T < 8
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Influence on line fluxes typical model for the region emitting the UV-X “continuum” of AGN Reflected continuum R=30 (Doppler width R=3-10) n H = 10 12 cm -3, CD = 10 25 cm -2, es = 4), F = cte (0.1 eV - 100 keV) (x10) on resonance lines, because line photons are reabsorbed. Dumont et al., A&A 2003
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Influence on line ratios Collin et al., A&A 2004 Typical model for the emission region of Seyfert 2 n H = 10 7 cm -3 (cte), no microturbulence : 30% at log(CD)=20 to (x5) at log(CD)=23. Turbulence (300 km/s) : < 50% (weaker optical thickness at line frequencies).
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Ionic abundance and temperature vs. CD Coupé et al., A&A 2004 Temperature, OVII fractional abundance
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G (O VII) ratio vs. CD Coupé et al., A&A 2004 Godet et al., A&A 2004 =5 =10 =30 =100 =300 =1000 =100 Grid of models (7<log n H <12, 18<log CD<23) G independant on n H R depends on log n H > 10 Influence of CD and Same G for several ( ,CD) values
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New Diagnostic OVII Godet et al., A&A 2004
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Angular distribution - global
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Angular distribution - O VII G = (z + x) / w, R = z / x, G or R change with inclination
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Future work Multi-angle applications (aperture constraint) PRD (this year) Atomic data Acceleration (SOR, parallel) Grids of models (VO) Public release (VO)
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APPENDICES
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He-like ion model (15 levels)
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EW (sum of O VII triplet) vs. CD One curve per value 7 < log n H < 12 Saturation 25 eV Same EW for several ( ,CD) values Coupé et al., A&A 2004
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Influence on line fluxes (thin) typical model for the region emitting the UV-X “continuum” of AGN Reflected continuum R=30 (Doppler width equivalent R=3-10) n H = 10 12 cm -3, CD = 10 24 cm -2, es = 0.8). Dumont et al., A&A 2003
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