INPE Advanced Course on Compact Objects

Course IV: Accretion Processes in Neutron Stars & Black Holes

Ron RemillardKavli Center for Astrophysics and Space ResearchMassachusetts Institute of Technology

http://xte.mit.edu/~rr/inpe_IV.2.ppt

IV.2 X-ray States of Black Hole Binaries Thermal States and Accretion Disk Models

Defining States: Energy and Power Density Spectra Observational Support for the Multicolor Disk Model Applying Relativistic Disk Models

Hard State, Jets, and Microquasars Hard State and a Steady Jet Advection Models (ADAF and CDAF) Synchrotron/Compton Models

Steep Power-Law of Black Hole Binaries Summary of Properties Link to High-Frequency QPOs

Further Considerations of BH X-ray States Overview of X-ray State Evolution Alternative Descriptions of X-ray States Statistics of State Occupations

X-ray States of BHBs

1. Thermal State:

inner accretion disk

X-ray States of BHBs

1. Thermal State: fdisk > 75%; rms < 0.075 ; no QPOs (amax < 0.5%)

inner accretion disk

Thermal State ParadigmTheory: Hot gas in thin disk + viscous dissipation Rel. MHD: Plasma + Magneto-Rotational Instability

Thermal radiation ; weakly magnetized 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; butsee Merloni & Fabian 2003

Emissivity vs. Radius in the Accretion Disk

GR Applications for Thermal State

Shakura & Sunyaev 1973; Makishima et al. 1986; Gierlinski et al. 1999; Zimmerman et al. 2005

Page & Thorne 1974; Zhang, Cui, & Chen 1997Gierlinski et al. 2001; Li et al. 2005

Relativistic Accretion Disk: Spectral Models

GR Applications for Thermal State

e.g. kerrbb in xspecLi et al. 2005; Davis et al. 2005

• Integrate over disk and B(T)

• Correct for GR effects(grav-z, Doppler, grav-focusing)

• Radiative transfer (i.e. f factor)

Thermal state X-ray spectra BH spin

Shafee et al. 2006; Davis, Done & Blaes 2006; McClintock et al. 2006

• Input Mx, d(kpc), disk inclination (i)

• Run model trials for values of:(viscosity parameter)model Comptonization (comptt, power-law, broken pow.)fit hardening factor vs. use Davis and Blaes model

• Derive a* (for various trials) in range of Lx

BH spin

McClintock et al. 2006

BH spin

McClintock et al. 2006

theory: disk should thicken near Lx ~ 0.3 LEDD

Thermal state BH spin

Shafee et al. 2006: a* ~ 0.75 for GROJ1655-40, 4U1543-47

Davis, Done & Blaes 2006: “moderate spin” (0.1-0.8) for XTEJ1550-564, LMC X-3

McClintock et al. 2006: a* > 0.98 for GRS1915+105

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Systematic concerns:

• Are -disk assumptions valid?

• Theory of radiative transfer (hardening factor) accurate?

• ISCO is smeared by B-coupling? (Page & Throne 1974; Agol & Krolik 2000)

Hard State of BHBs 2. Hard State fdisk < 20%; ~ 1.4 - 2.1; rms > 0.10

steady jet

Hard State of BHBs: Steady Radio Jet

2. Hard State fdisk < 20%; ~ 1.4 - 2.1; rms > 0.10

radio : X-ray correlations: Corbel et al. 2000; Gallo et al. 2003

Hard State of BHBs: Steady Radio Jet

Corbel et al. 2000

Hard State of BHBs: Steady Radio Jet

50730 50740 50750

MJD

GRS1915+105 Oct. 1 – Nov. 7, 1997

X-ray c/s

H-ray HR

Radio Flux

Radio index

Modeling the Hard State

ADAF models:(Advection-Dominated Accretion Flow)

• transition: Keplerian to quasi-radial inflow at ~100-500 Rg

• energy ‘advected’ into BH• electrons can still radiate some synchrotron and inverse Compton

controversies! Model evolution!ADAF CDAF (convective DAF)

more outflow

XTEJ1118+480 (low NH)….truncated, cool disk(McClintock et al. 2001)

Modeling the Hard State

Hybrid models:• Synchrotron/Compton (Markoff, Nowak, & Wilms 2005) Kalemci et al. 2005

• ADAF-fed Syn./Comp.? (Yuan, Cui, & Narayan 2005)

XTEJ1118+480 synchrotron model(Markoff et al. 2001)

States of Black Hole Binaries

3. steep power law compact corona ?

> 2.4; rms < 0.15 ;

fdisk < 80% + QPOs (or fdisk< 50%)

mechanism? : inverse Compton

origin? : magnetized disk ?Energy spectra Power density spectra

1 10 100 .01 .1 1 10 100 Energy (keV) Frequency (Hz)

Neutron stars (atoll type) have thermal and hardStates, but they never show SPL-dominated spectra

Steep Power Law

Gamma Ray Bright State(Grove et al. 1998)

blackbody energetics

SPL

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Physical Models for BHB StatesEnergy spectra Power density spectra

State physical picture

steep power law Disk + ??

thermal

hard state

Energy (keV) Frequency (Hz)

Are they different?

Very different X-ray spectra Extremely Different Gamma Ray Spectra QPOs vs. none

Conclusions: Do not combine thermal and SPL “soft” 3 X-ray States 3 Accretion Systems

Comparing SPL vs. Thermal States

High Frequency QPOs (40-450 Hz)

High Frequency QPOs

source HFQPO (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: = 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 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

HFQPO Frequencies vs. BH Mass

GROJ1655, XTEJ1550,

and GRS1915+105

qpo at 2o: o = 931 Hz / Mx

Same QPO mechanism and similar value of a*

Compare subclasses

while model efforts continue

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. 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.)

AEI + Rossby vortex (Tagger & Varniere 2006)

BH Outbursts & States

GRO J1655-40

1996-97 outburst

Thermal x

Hard (jet)

Steep Power Law

Intermediate O

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

Hard Color

X-rayintensity

BH States: OverviewGX339-4

Mx = 5 – 15 Mo

Frequent outbursts: 1970 - 2005+ extended, faint, hard states

Thermal x

Hard (jet)

Steep Power Law

Intermediate O

BH States: Overview

GRO J1655-40

1996-97 outburst

Thermal x

Hard (jet)

Steep Power Law

Intermediate O

BH States: OverviewH1743-322

Mx unknown (ISM dust)

HEAO-1 outburst: 1977RXTE: 2003; minor outburst 2005

Thermal x

Hard (jet)

Steep Power Law

Intermediate O

BH States: OverviewXTEJ1550-564

Mx = 9.6 + 1.2 Mo

Outbursts: 1998 ; smaller, 2000; + 3 faint hard-state outbursts

2001, 2002, 2003

Thermal x

Hard (jet)

Steep Power Law

Intermediate O

Black Hole States: Statistics

XTE J1550-564 GRO J1655-40 XTE J1118+480

Steep Power Law 26 15 0Thermal 147 47 0Low/hard 22 2 10

Intermediate 57 2 0

Timescales (days) for state (all BH Binaries)

duration transitionsSteep Power Law 1-10 <1Thermal 3-200 1-10Low/hard 3-200 1-5

Intermediate 3-30 1-3

Low Frequency QPOs (0.05-30 Hz)

XTE J1550-5641998 Sept. 23

QPO: 4 Hz, 12% rms

Q ~ 9

Flux 2 Crab (~0.2 LEdd)

fdisk = 0.1

QPO wave tracking

random walk in phase(Morgan et al. 1997)

Low Frequency QPOs : Subtypes

Type: A B CPhase Lag: soft hard near zero (Hz): ~8 ~6 0.1 – 15a (rms %) few few 5 – 20 Q : 2 – 3 ~10 ~10State: SPL SPL Hard/Int.

HFQPO coupling yes, 3o yes, 2o no HFQPOs

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

XTEJ1550-564

LFQPO Mechanisms Periastron precession of emitting blobs in GR (Stella et al. 1999)

Frame Dragging in GR (Stella & Vietri 1998; Fragile et al. 2001)

Resonance oscillation sidebands (Horak et al. 2004)

p-mode oscillations in a truncated disk (Giannios & Spruit 2004)

Inertial-Acoustic oscillations (Milson & Taam 1997)

Global disk oscillations (Titarchuk & Osherovich 2000)

Alfven waves (C.M. Zhang et al. 2005)

Accretion-Ejection Instability in disk (magnetic spiral waves)

(Tagger & Pellat 1999)

Radial oscillations in accretion shocks

(Molteni et al. 1996; Chakrabarti & Manickam 2000)

QPO Frequency vs. Disk Flux

? different types of magnetized disk ?