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MIT Workshop on Magnetized Accretion Disks

This presentation will probably involve audience discussion, which will create action items. Use PowerPoint to keep track of these action items during your presentation In Slide Show, click on the right mouse button Select “Meeting Minder” Select the “Action Items” tab

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MIT Workshop on Magnetized Accretion Disks

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  1. This presentation will probably involve audience discussion, which will create action items. Use PowerPoint to keep track of these action items during your presentation • In Slide Show, click on the right mouse button • Select “Meeting Minder” • Select the “Action Items” tab • Type in action items as they come up • Click OK to dismiss this box • This will automatically create an Action Item slide at the end of your presentation with your points entered. MIT Workshop on Magnetized Accretion Disks October 19 & 20, 2006 Supported by: MIT-France Program CEA Saclay, France MIT Kavli Inst. for Astrophysics & Space Research MIT Dept. EE&CS RXTE Project

  2. Workshop Handouts & Logistics • Schedule: (4 sessions) • Name Tag • List of Participants • MIT wireless instructions for visitors • Thursday dinner? …stay here after session 2 Legal Seafoods? Cambridge Brewery?

  3. This presentation will probably involve audience discussion, which will create action items. Use PowerPoint to keep track of these action items during your presentation • In Slide Show, click on the right mouse button • Select “Meeting Minder” • Select the “Action Items” tab • Type in action items as they come up • Click OK to dismiss this box • This will automatically create an Action Item slide at the end of your presentation with your points entered. X-ray States of Black Hole Binaries: Observations and Physical Models Ron Remillard MIT Kavli Center for Astrophysics and Space Research

  4. Workshop Motivations • Assess status of BH accretion physics General relativity astrophysics at 10 Rg? X-ray states versus accretion models critical need for steep power-law / QPO paradigm discussions of magnetism in accretion disks • Communicate: observers ; theorists ; GR/MHD physicists 1.5 years since last UCSB program on BH theory informal format for hard results + views & intuitions motivate future work

  5. Active X-ray States of BH Binaries • Thermal State: thermal spectrum ; L aT4 ; no QPOs Paradigm: Heat from weakly magnetized accretion disk • Hard State: flat, cutoff power law ; cool disk ; some QPOs Concept: Compton/synchrotron from steady jet (+ ADAF?) Jets are confined by magnetic fields from the disk? • Steep Power Law: thermal + SPL + QPOs + HFQPOs ?? Magnetized Accretion Disk ; Accretion Torus ??

  6. Black Hole X-ray Nova GRO J1655-40 First known outbursts: 1994-95; () 1996-97; 2005 Dynamical black hole binary 6.3 (+0.5) Mo Relativistic Jets in 1994 ~Radio-quiet, 1996-97, 2005

  7. Black Hole X-ray Nova GRO J1655-40  Different X-ray States

  8. Observation Reviews & Global Studies Done & Gierlinski 2003MNRAS, 342, 1041 Fender 2006Compact Stellar X-ray Sources, Ch. 9 Fender & Belloni 2004ARAA, 42, 317 Charles & Coe 2006Compact Stellar X-ray Sources, Ch. 5 McClintock & Remillard 2006Compact Stellar X-ray Sources, Ch. 4 Psaltis 2006 Compact Stellar X-ray Sources, Ch. 1 Remillard & McClintock 2006ARAA, 44, 49 van der Klis 2006Compact Stellar X-ray Sources, Ch. 2 Zdziarski & Gierlinski 2004PThPS, 155, 99

  9. X-ray States of BHBs • ThermalState: fdisk > 75%; rms < 0.075 ; no QPOs (amax < 0.5%) • inner accretion disk

  10. X-ray States of BHBs • ThermalState: • classical disk model: T(r) ~ r-3/4 L(r) ~ r-2

  11. Heat from Accretion Disk ? modified disk blackbody blackbody energetics GR/Keplerian velocities? GX339-4 Relativistic Fe line e.g. Miller et al. 2004; but see Merloni & Fabian 2003 Kubota & Done 2004; Gierlinski & Done 2004 T(r)ar-p; p ~ 0.7 (Kubota et al 2005) (GR tweak of p=0.75)

  12. Thermal State Paradigm ? Spectral shape and luminosity evolution consistent with thermal-disk model: Hot gas in Keplerian orbits + efficient dissipation GR/MHD Simulations: Plasma + Magneto-Rotational Instability (MRI): ~Keplerian orbits ; high b = Pgas / (B2/8p)  Thermal Radiation from a Weakly Magnetized Disk Alternatives:low b inner disk (external seed B) ? Plasma Rings (Coppi & Rousseau 2006) ? GR MHD: Stronger jets with higher spin ?  Other X-ray states?

  13. Hard State of BHBs   2. Hard State fdisk < 20%; G ~ 1.4 - 2.1; rms > 0.10 steady jet(radio emission: collimated, polarized, flat spectrum)

  14. Hard State of BHBs: Steady Radio Jet  2. Hard State fdisk < 20%; G ~ 1.4 - 2.1; rms > 0.10 steady jet(radio : X-ray tight correlation Gallo et al. 2003)

  15. States of Black Hole Binaries • 3. steep power law • compact corona ? • G > 2.4; rms < 0.15 ; fdisk < 80% + QPOs (or fdisk< 50%) 1 10 100 .01 .1 1 10 100 Energy (keV) Frequency (Hz) Energy spectraPower density spectra Neutron stars (atoll type) have thermal and hard states, but they never show strong SPL spectra!

  16. Hard State of BHBs • mechanism? geometry? •  Hybrid models: • Synchrotron/Compton • (Markoff, Nowak, & Wilms 2005) • Kalemci et al. 2005 • ADAF-fed Syn./Comp.? • (Yuan, Cui, & Narayan 2005) • Cause of jets?(GRMHD?) • Vertical, external B can amplify • modest outflows of standard sims. XTEJ1118+480 (low NH)….truncated, cool disk (McClintock et al. 2001)

  17. Steep Power Law BHB Gamma Ray Bright State (Grove et al. 1998) blackbody energetics SPL |

  18. Physical Models for BHB States Energy spectraPower density spectra Statephysical picture steep power law Disk + ??  thermal hard state Energy (keV) Frequency (Hz)

  19. 3 X-ray States  3 Different Accretion Systems? • Energy spectra  YES! • Statistical Distributions in key parameters  YES! 6 BHBs [417 thermal; 214 hard; 184 SPL; 179 INT (all types)] GRO J1655-40 (1996-97) XTEJ1550-564 (4 outbursts) XTE J1859+226 (1999-2000) GX339-4 (3 outbursts) 4U1543-47 (2002) H1743-322 (2003) • Power law : thermal (disk) coupling  YES!

  20. Distributions in Photon Index Hard SPL Thermal

  21. Distributions in Temperature Hard ThermalSPL

  22. Distributions in Disk Fraction (2-20 keV) Hard SPLThermal

  23. “Unified Model for Jets in BH Binaries” Fender, Belloni, & Gallo 2004 Remillard 2005

  24. Coupling: power-law and thermal components GRO J1655-40 XTE J1859+226 XTE J1550-564 Hard: cannot see diskThermal : yesSPL : no

  25. Conclusions • Observationsof BH X-ray states : need 3 models ! • Thermal state: weakly magnetized disk (GR/MCD + MRI) seems quite satisfactory • Hard state: key topics: hot flow : jet coupling ; spin? • SPL state : PL:disk flux uncoupled; non-thermal corona (to MeV?); LFQPOs ; HFQPOs ; kinship to hard state is a key question

  26. GR in SPL State: High Frequency QPOs

  27. High Frequency QPOs source HFQPO n (Hz) GRO J1655-40 300, 450 XTE J1550-564 184, 276 GRS 1915+105 41, 67, 113, 168 XTE J1859+226 190 4U1630-472 184 + broad features (Klein-Wolt et al. 2003) XTE J1650-500 250 H1743-322 166, 242 ------- ISCO for 10 Mo BH: nf = 220 Hz (a* = 0.0)  728 Hz (a* = 0.9) Condensations at preferred radii  QPOs (Schnittman & Bertschinger 2004)

  28. High Frequency QPOs source HFQPO n (Hz) GRO J1655-40 300, 450 XTE J1550-564 184, 276 GRS 1915+105 41, 67, 113, 168 XTE J1859+226 190 4U1630-472 184 XTE J1650-500 250 H1743-322 165, 241 ------- 4 HFQPO pairs with frequencies in 3:2 ratio

  29. HFQPOs Mechanisms • Diskoseismology (Wagoner 1999 ; Kato 2001)  obs. frequencies require nonlinear modes? • Resonance in Inner Disk (Abramowicz & Kluzniak 2001). • Parametric Resonance (coupling in GR frequencies for {r, q}Abramowicz et al. 2004 ; Kluzniak et al. 2004; Lee et al. 2005) • Resonance with Global Disk Warp (S. Kato 2004) • MHD Simulations and HFQPOs (Y. Kato 2005) • Torus Models (Rezzolla et al. 2003; Fragile et al. 2005) • GR ray tracing of accretion torus (Bursa et al.) • Other Models (disk magnetosphere effects: Li & Narayan 2004 ; Alfven waves: Zhang et al. 2004)

  30. HFQPO Frequencies vs. BH Mass GROJ1655, XTEJ1550, and GRS1915+105 nqpo at 2no: no = 931 Hz / Mx • Same QPO mechanism and similar value of a* • Compare subclasses while model efforts continue

  31. LFQPO Subtypes XTEJ1550-564 Wijnands et al. 1999 Cui et al. 1999 Remillard et al. 2002 Rodriguez et al. 2004 Casella et al. 2005 QPOs across states Jet  INT  SPL ?? diff. mechanism ?? evolution in magnetic instability Type: A B C Phase Lag: soft hard near zero n0 (Hz): ~8 ~6 0.1 – 15 a (rms %) few few 5 – 20 Q : 2 – 3 ~10 ~10 State: SPL SPL Hard/Int. HFQPO coupling yes, 3noyes, 2no no HFQPOs

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