Download
slide1 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Relativistically Broad Iron K-Lines of AGN “ Probing BH spin ” PowerPoint Presentation
Download Presentation
Relativistically Broad Iron K-Lines of AGN “ Probing BH spin ”

Relativistically Broad Iron K-Lines of AGN “ Probing BH spin ”

133 Vues Download Presentation
Télécharger la présentation

Relativistically Broad Iron K-Lines of AGN “ Probing BH spin ”

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Relativistically Broad Iron K-Lines of AGN “Probing BH spin ” Y. Tanaka June 22, 2011 @ICRR

  2. Black Holes are Very Simple • Mass: M • Spin: J = a*GM2/c (0 < a* < 1) • (Electric Charge: Q) • But to measure these quantities is not simple • Two feasible methods for estimating spin: • Determine RISCO of an accretion disk applicable to stellar-mass BH in the soft (X-ray) state. Mass, Distance, Inclination optically determined. • 2. Relativistically broad Fe-K line Fe-K line near BH is broadened redward due to Doppler effect and gravitational redshift (depends ona). *

  3. X-ray spectra of BH binaries in the “soft state”Multicolor blackbody disk (MCD) model(Ginga)

  4. DetermineRISCObased on theMCD model Based on the MCD model, corresponds to RISCO Spinsof several BH in binaries estimated (McClintock et al 2011)

  5. R ISCO/rg vs Spin parametera * R

  6. Black Holes are Very Simple • Mass: M • Spin: J = a*GM2/c (0 < a* < 1) • (Electric Charge: Q) • But to measure these quantities is not simple • Two feasible methods: • DetermineRISCO of an accretion disk applicable to stellar-mass BH in the soft (X-ray) state. Mass, Distance, Inclination optically determined. • 2. Relativistically broad Fe-K line Fe-K line near BH is broadened redward due to Doppler effect and gravitational redshift (depends ona). *

  7. “Broad Iron Line” story initiated in 1985 Cyg X-1 Tenma Kitamoto et al. EXOSAT Barr et al. narrow broad Gas scintillation prop. counter: best energy resolution at that time

  8. Iron K-Line profile nearablackhole Rest frame @6.4 keV Newtonian Fabian et al. 1989 Special Relativity: Beaming and Transverse Doppler General Relativity: Gravitational Redshift Disk Emissivity nobs/nem by Armitage & Reynolds

  9. SPIN Maximal Kerr

  10. MCG-6-30-15 (z=0.008) Broad Fe-K line first observed with ASCA Tanaka, Fabian et al 1994

  11. Broad Fe-K Line from the AGN MCG-6-30-15(z=0.008) first observed with ASCA Flux (photons Energy (keV) Tanaka, Fabian et al. (1995)

  12. MCG-6-30-15 SUZAKU Red wing due to large gravitational redshift implying BH rapidly spinning a > 0.98 *

  13. Broad Fe K-Lines observed with ASCA K. Nandra

  14. Broad Fe K-Lines in Galactic BHBs XTE J1550-564 (ASCA) GRS 1915+105 (CXO) Cyg X-1 (XMM) (JMM 02, 06) (JMM 04) (JMM 04) XTE J1650-500 (XMM) GX 339-4 (CXO) (JMM 04) GRO J1655-40 (ASCA) (JMM 02) Broad Fe line in ~20 systems: [J.Miller]

  15. Fe K emission line • Most prominent feature in X-ray spectrum of reprocessed (reflected) emission from surrounding matter (accretion disk, torus ?) • Relativistic broad line is the result of strong gravitational field near the central BH • Probing the spin of BH, in particular SMBH • But the reality of the Relativistic Broad Line is still subject of debate ! because the line profile is sensitive to the underlying continuum. Fixing the correct continuum is not straightforward.

  16. Compton-thick partial coverer may mimic a broad line Partial Covering 「すざく」 HXD 海老沢 天文月報 p445, vol.103, 2010

  17. Patchy Absorber taken from Dewangan 2011

  18. Compton-thick partial coverer may mimic a broad line Partial Covering 「すざく」 HXD 海老沢 天文月報 p445, vol.103, 2010

  19. A convincing case exists. 1H0707-495 NarrowLineSeyfert1 Optical properties:_____narrow H lines: FWHM Hß<2000 km/s _____relatively weak [O III]l5007_____strong FeII emission X-ray properties:_____steep power law: photon index > 2.0_____significant soft excess _____rapid & large-amplitude variation considered to be relatively low mass & high Eddington ratio

  20. 1H0707-495 time variability Gallo et al. 2004

  21. Examples of NLS1 Deep edge, Strong soft comp. Γ= 2.4 Edge:7.1keV (Boller et al. 2002) Γ= 2.5 Edge:8.2keV (Boller et al. 2003)

  22. “Partial Covering” fit to two NLS1 spectra Note the absence of narrow Fe-K line

  23. kT:100~150 eV Over mass range of three orders of magnitude Excludes accretion disk origin !

  24. Reflection from photoionized disk (Ross & Fabian 93, 04) Fe-K line must be present ! Also see Young+, Nayakshin+, Ballantyne+, Rozanska+, Dumont+

  25. XMM RGS Spectrum of the Soft Excess ____________________of 1H0707 Fe-L Blustin & Fabian 09

  26. Ratio to the PL + BB model a > 0.98 *

  27. Remaining Issues • Why not all AGN show broad lines? • How to determine the correct continuum ? • Black hole spin: tend to be high ( too few sample yet) • NLS1: show distinct differences from BLS1 ______strong soft excess ______steep power-law ______lack of narrow Fe K-line ______high Fe abundance

  28. Strong light bending close to BH Martocchia & Matt, Miniutti & Fabian