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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
  • 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

workshop handouts logistics
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

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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X-ray States of Black Hole Binaries: Observations and Physical Models

Ron Remillard

MIT Kavli Center for Astrophysics and Space Research

workshop motivations
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

active x ray states of bh binaries
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 ??

black hole x ray nova
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

black hole x ray nova7
Black Hole X-ray Nova

GRO J1655-40

 Different X-ray States

observation reviews global studies
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

x ray states of bhbs
X-ray States of BHBs
  • ThermalState: fdisk > 75%; rms < 0.075 ; no QPOs (amax < 0.5%)
  • inner accretion disk
x ray states of bhbs10
X-ray States of BHBs
  • ThermalState:
  • classical disk model: T(r) ~ r-3/4 L(r) ~ r-2
heat from accretion disk
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)

thermal state paradigm
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?

hard state of bhbs
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)

hard state of bhbs steady radio jet
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)

states of black hole binaries
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!

hard state of bhbs16
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)

steep power law
Steep Power Law

BHB Gamma Ray Bright State

(Grove et al. 1998)

blackbody energetics

SPL

|

physical models for bhb states
Physical Models for BHB States

Energy spectraPower density spectra

Statephysical picture

steep power law Disk + ??

 thermal

hard state

Energy (keV) Frequency (Hz)

3 x ray states 3 different accretion systems
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!
unified model for jets in bh binaries
“Unified Model for Jets in BH Binaries”

Fender, Belloni, & Gallo 2004 Remillard 2005

coupling power law and thermal components
Coupling: power-law and thermal components

GRO J1655-40 XTE J1859+226 XTE J1550-564

Hard: cannot see diskThermal : yesSPL : no

conclusions
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

high frequency qpos
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)

high frequency qpos28
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

hfqpos mechanisms
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)

hfqpo frequencies vs bh mass
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

lfqpo subtypes
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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