MIT Workshop on Magnetized Accretion Disks Supported by: MIT-France Program CEA Saclay, France MIT Kavli Inst. for Astrophysics & Space Research MIT Dept. EE&CS RXTE Project 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. October 19 & 20, 2006
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?
X-ray States of Black Hole Binaries: Observations and Physical Models Ron Remillard MIT Kavli Center for Astrophysics and Space Research 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.
Workshop Motivations Assess status of BH accretion physics General relativity astrophysics at 10 R g ? 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
Active X-ray States of BH Binaries Thermal State: thermal spectrum ; L T 4 ; 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 ??
Black Hole X-ray Nova GRO J First known outbursts: ; ( ) ; 2005 Dynamical black hole binary 6.3 ( 0.5) M o Relativistic Jets in 1994 ~Radio-quiet, , 2005
Black Hole X-ray Nova GRO J Different X-ray States
Observation Reviews & Global Studies Done & Gierlinski 2003 MNRAS, 342, 1041 Fender 2006 Compact Stellar X-ray Sources, Ch. 9 Fender & Belloni 2004 ARAA, 42, 317 Charles & Coe 2006 Compact Stellar X-ray Sources, Ch. 5 McClintock & Remillard 2006 Compact Stellar X-ray Sources, Ch. 4 Psaltis 2006 Compact Stellar X-ray Sources, Ch. 1 Remillard & McClintock 2006 ARAA, 44, 49 van der Klis 2006 Compact Stellar X-ray Sources, Ch. 2 Zdziarski & Gierlinski 2004 PThPS, 155, 99
X-ray States of BHBs 1.Thermal State: f disk > 75%; rms < ; no QPOs (a max < 0.5%) inner accretion disk
X-ray States of BHBs 1.Thermal State: classical disk model: T(r) ~ r -3/4 L(r) ~ r -2
Heat from Accretion Disk ? T(r) r -p ; p ~ 0.7 (Kubota et al 2005) (GR tweak of p=0.75) modified disk blackbody GX339-4 Relativistic Fe line blackbody energetics GR/Keplerian velocities? Kubota & Done 2004; Gierlinski & Done 2004 e.g. Miller et al. 2004; but see Merloni & Fabian 2003
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 = P gas / (B 2 /8 ) Thermal Radiation from a Weakly Magnetized Disk Alternatives:low inner disk (external seed B) ? Plasma Rings (Coppi & Rousseau 2006 ) ? GR MHD: Stronger jets with higher spin ? Other X-ray states?
Hard State of BHBs 2. Hard State f disk 0.10 steady jet (radio emission: collimated, polarized, flat spectrum)
Hard State of BHBs: Steady Radio Jet 2. Hard State f disk 0.10 steady jet (radio : X-ray tight correlation Gallo et al. 2003)
States of Black Hole Binaries 3. steep power law compact corona ? > 2.4; rms < 0.15 ; f disk < 80% + QPOs (or f disk < 50%) Energy spectra Power density spectra Energy (keV) Frequency (Hz) Neutron stars (atoll type) have thermal and hard states, but they never show strong SPL spectra!
Hard State of BHBs mechanism? geometry? Hybrid models: Synchrotron/Compton (Markoff, Nowak, & Wilms 2005) Kalemci et al ADAF-fed Syn./Comp.? (Yuan, Cui, & Narayan 2005) Cause of jets? (GRMHD?) Vertical, external B can amplify modest outflows of standard sims. XTEJ (low N H )….truncated, cool disk (McClintock et al. 2001)
Steep Power Law BHB Gamma Ray Bright State (Grove et al. 1998) blackbody energetics SPL ||
Physical Models for BHB States Energy spectra Power density spectra State physical picture steep power law Disk + ?? thermal hard state Energy (keV) Frequency (Hz)
Energy spectra YES! Statistical Distributions in key parameters YES! 6 BHBs [417 thermal; 214 hard; 184 SPL; 179 INT (all types)] GRO J ( ) XTEJ (4 outbursts) XTE J ( ) GX339-4 (3 outbursts) 4U (2002) H (2003) Power law : thermal (disk) coupling YES! 3 X-ray States 3 Different Accretion Systems?
Hard SPL Thermal Distributions in Photon Index
Hard Thermal SPL Distributions in Temperature
Hard SPL Thermal Distributions in Disk Fraction (2-20 keV)
“Unified Model for Jets in BH Binaries” Fender, Belloni, & Gallo 2004 Remillard 2005
GRO J XTE J XTE J Coupling: power-law and thermal components Hard: cannot see disk Thermal : yes SPL : no
Conclusions Observations of 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
GR in SPL State: High Frequency QPOs
High Frequency QPOs source HFQPO (Hz) GRO J , 450 XTE J , 276 GRS , 67, 113, 168 XTE J U broad features (Klein-Wolt et al. 2003) XTE J H , ISCO for 10 M o BH: = 220 Hz (a * = 0.0) 728 Hz (a * = 0.9) Condensations at preferred radii QPOs (Schnittman & Bertschinger 2004)
High Frequency QPOs source HFQPO (Hz) GRO J , 450 XTE J , 276 GRS , 67, 113, 168 XTE J U XTE J H , HFQPO pairs with frequencies in 3:2 ratio
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, } Abramowicz et al ; 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)
HFQPO Frequencies vs. BH Mass GROJ1655, XTEJ1550, and GRS qpo at 2 o : o = 931 Hz / M x Same QPO mechanism and similar value of a * Compare subclasses while model efforts continue
LFQPO Subtypes Type: AB C Phase Lag: soft hard near zero (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, 3 o yes, 2 o no HFQPOs Wijnands et al Cui et al Remillard et al Rodriguez et al Casella et al QPOs across states Jet INT SPL ?? diff. mechanism ?? evolution in magnetic instability XTEJ