X-ray Spectroscopy of Cool & Warm Absorbers With Chandra: From Oxygen to iron X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA Norbert S. Schulz 1.X-ray Absorption Processes 2. Benefits, Challenges & Future of High Resolution X-ray Absorption Spectroscopy 3. Cool & Warm X-ray Absorbers: -Interstellar Media (ISMs) in Galaxies -Accreting X-ray Binaries -Active Galactic Nuclei (AGN)
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes Photoelectric Continuum Absorption
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes Absorption in Cool Matter/Plasmas Photo-electric continuum absorption X-ray fluorescence Photo-electric 1s-np resonances
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes New Models for ISM Absorption Juett, Wilms, Schulz & Nowak 2006 (tbnew in XSPEC)
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes Absorption in Collisionally Ionized Plasmas Collisional Ionization Equilibrium kT > MK H-, He-like resonance absorption ( and Li-, B-like for Fe) Fermi's Golden Rule: P i-f = 2 /h | | 2 (E f = E i )
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes Absorption in PhotoionizedPlasmas Warm absorber: electron temperature of illuminated matter << 10 6 K in contrast to a collisionally ionized gas gas with a similar level of ionization ( Halpern 1984) Ionization parameter = L x / n e d 2 C. Reynolds
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes XSTAR v2.1 simulations: Log L x ~ 37.5 [erg/s], < 2 Kallman et al. 2004
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA Determine matter properties: optical depths: (Z) columns densities: N Z, N warm, N hot abundance: A Z composition: elements, molecules geometry: d , d ionization balance: f Z dust properties/depletion 2. Benefits, Challenges & Future of High Resolution X-ray Absorption Spectroscopy Chemical evolution and recycling of matter: - accurate ccount of matter (non- radiative), - accretion dignostics, -inert cool, warm & hot absorbers in ISM/IGM
Curve of Growth Analysis Evaluation of measured equivalent width: -column densities -line oscillator strengths -mass dynamics - linear part - flat part - sqrt part
Current Spectral Capabilies Available Spectrometers: RGS XMM-Newton ~ 0.08 FWHM RGS 1 ~ 0.06 RGS 2 LETG Chandra ~ 0.05 FWHM HETG Chandra ~ 0.02 FWHM MEG ~ 0.01 HEG (CCD have E/dE < 60) Wavelength range (z=0): 45 A (C-K) -- 1,7 A (Fe K) Resolving power > 1000 desired Velocities > 150 km/s resolved Equivalent Widths ~ mA possible
Resolution vs. Efficiency = 1200 A eff ~ 100 cm 2 = 200 A eff ~ 6000 cm 2 = 2000 A eff ~ 1200 cm 2
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA Critical Angle Transmission Gratings for Con-X
Phases of Interstellar Media Phase n/[ccm] T/[K] Media Cold MCs, H I Warm < H I, H II Hot <0.005 < 10 MK SNR - (Very hot) Diffuse
Chandra HETG ISM Surveys O-K absorption Ne K absorption: Ne II, III, IX X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA Juett et al Juett et al. 2006
Ne abundance: Ne II, IIIO abundance: O II, III Chandra HETG ISM Surveys X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Absorption in X-ray sources Absorption in collisionally ionized plasmas: Collisional Ionization Equilibrium kT > MK H-, He-like resonance absorption ( and Li-, B-like for Fe) NeII K Resonance Absorption in the Hot ISM X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Future: Absorption Surveys in Galaxies ISM Studies in other Galaxies Principle: backlighting with bright X-ray continua Advantage: Long-range analysis Entire Galactic plane & Halo Study all ISM phases X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Warm absorbers in Seyfert I galaxies: Soft absorber in warm plasma: I. George X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Texas Symposium 2006, Dec. 12, Melbourne, Australia Warm absorbers in Seyfert I galaxies: X-ray spectra of Active Galactic Nuclei NGC 3783, Kaspi et al MCG , Lee et al Blustin et al. 2005
Warm Absorbers in Compact Binaries: Summary Table: X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Warm Absorbers in Compact Binaries: Summary Table: X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Hot Absorbers in Compact Binaries: Summary Table: X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Warm Absorbers in Compact Binaries: Summary Table: X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Warm Absorbers in Compact Binaries: EXO Jimenez-Garate, Schulz, & Marshall (2003)Cottam et al. (2003) X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Warm Absorbers in Compact Binaries: Microquasars GRO J (Miller et al.2006a) H (Miller et al. 2006b) Cyg X-1 (Marshall et al. 2001, Miller et al. 2005) Cir X-1 (Brandt & Schulz 2000) GRS Lee et al X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Warm Absorbers in Compact Binaries: Microquasars: the special case of Cir X-1 The X-ray binary with two faces: at high X-ray fluxes (>1 Crab) high ionization parameter: log > 4 blueshifts: v outflow = km/s cold and hot absorber present at low X-ray fluxes (<100 mCrab) microquasar low ionization parameter: log = no blueshifts cold, lukewarm, warm absorber present atol dipper Schulz & Brandt (2002) Schulz et al. (2007) ApJ, submitted X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA
Summary 1) High resolution (R > 500) X-ray spectrom,eters have opened the window for absorption spectroscopy as a powerful diagnostic in high energy astrophysics 2) Benefits: line absorption in the X-ray band cover a large range of T [ K], log [ ], N H [ cm -2 ]; measure direct abundance & ionization fractions for Z = ) Detection of absorption edge structure in O, Fe, Ne; optical depth measurements for O, Ne, Mg, Si, S, Fe; first measurments of ionization fractions involving warm ISM phase 4) Detections of cool, warm, hot absorber properties in a large range of objects: ISM, IGM (WHIM), AGN, LMXBs, HMXBs 6) We have met the challenge for more powerful X-ray spectrometers -- SO WHERE IS THE NEW MISSION? 5) First detection of an active warm absorber in an accreting NS binary: Cir X-1 (see also EXO )
X-ray Grating Spectroscopy, July 12, 2007, Cambridge MA, USA 1.X-ray Absorption Processes Absorption in Cool Matter/Plasmas