Black Hole Coalescence: The Gravitational Wave Driven Phasemctp/SciPrgPgs/events/2011/Blackholes/...Black Hole Coalescence: The Gravitational Wave Driven Phase Jeremy Schnittman Overview

Overview EM counterparts Sources Precursors Prompt Emission Trojan Analogs Next Steps/Conclusion

Black Hole Coalescence: The Gravitational WaveDriven Phase

Jeremy Schnittman

NASA Goddard

UM Black HolesAugest 24, 2011

Black Hole Coalescence: The Gravitational Wave Driven Phase Jeremy Schnittman


Motivation

Observing supermassive black hole mergers will teach us about

Relativity

High-energy Astrophysics

RadiationHydrodynamics

Cosmology

Galaxy Formation andEvolution

Stellar Evolution

Dark Matter



Motivation

Observing supermassive black hole mergers will teach us about

Relativity

High-energy Astrophysics

RadiationHydrodynamics

Cosmology

Galaxy Formation andEvolution

Stellar Evolution

Dark Matter



Time scales

“final parsec” problem (maybe) not such a big problem after all

triaxial galaxies e.g., Merritt & Poon 04, Preto+ 11

massive perturbers Perets & Alexander 08

high eccentricities Quinlan 96, Preto+ 11

circumbinary gas disk Callegari, Cuadra, Dotti, Van Wassenhove, ...



Time scales, con’t

Tanaka+ 11

101 102 103 104 105

disk radius (M)

101

102

103

104

105

106

107

time

(yr)

tGW

~R4

tinflow

~R5/4 (gas)

tinflow

~R7/2 (rad)

JS & Krolik 08




vaccuum binary merger is basically a solved problemt < 2005: “Kip diagram”




vaccuum binary merger is basically a solved problemt > 2005: “Joan diagram”



EM counterparts – What do we know?

galaxy mergers + ubiquitous SMBHs

remarkably few AGN pairs, no triples

phases of BH binary evolution

stellar dynamical frictiongas dynamical frictionGW loss

post-Newtonian + numerical relativity

kick formula for known masses, spins



EM counterparts – What do we need to know?

galaxy merger rates (dependence on masses, mass ratio, gasfraction, etc.)

BH parameters

BH massesBH spins: amplitude and orientation

BH environment prior to merger

quantity and quality of gasstellar distribution and age/metallicityproperties of circumbinary disk



What we will learn

galaxy environs: gas vs stars

high-velocity end of kick distribution

time delay between galaxy, BH merger

w/ PTA: merger rates for M & 108M, z . 1

w/ LISA: rates, masses, spins for M . 106−7M, z .∞LD vs z out to z ∼ 1

w/ LIGO: rates, masses, spins for M . 102M, z . 0.3



Diversity of Sources (theorist)

−10 yr 9 10 yr9−10 yr 3 10 yr3 10 yr6−10 yr 6 0 yr

HCSSs

off−centered/Doppler−shiftedquasars

suppressedaccretion

X−ray/UV/IR afterglows

DM annihilationBondi accretion

delayed quasar

106

103

100

10−3

10−6

galaxy mergers

M−sigma

occup. fractiondiffuse gas

X−shapedradio lobes

galaxy cores (scouring) galaxy cores (recoil)

enhancedaccretion

(pulsar timing)GW’s variable

accretion tidal disruption

diskscircumbinary

R(pc

)

time since merger

GRMHD

dual AGN

binary quasars

accretiondisks

darkmatter

stars

hot gas

GWs

LISA



Diversity of Sources (observer)

−10 yr 9 10 yr9−10 yr 3 10 yr3 10 yr6−10 yr 6 0 yr

102

100

10−2

10−4

10−6

10−10

GRMHD

dual AGN

angu

lar s

ize

(arc

sec)

(pulsar timing)GW’s

binary quasars

delayed quasar

X−ray/UV/IR afterglows

diskscircumbinary

variableaccretion enhanced

accretionsuppressedaccretion

tidal disruptionDM annihilation

Bondi accretion

off−centered/Doppler−shiftedquasars

HCSSs

galaxy cores (scouring) galaxy cores (recoil)

M−sigmadiffuse gas

occup. fractiongalaxy mergers

time since merger (lifetime of source)

X−shapedradio lobes

LISA

gam−ray

GW

X−ray

O/UV

IR

radio



Pulsar timing arrays

Hobbs+ 10



PTA sources

Sesana+ 11



Future wide-field surveys

LOFAR → SKA

PanSTARRS → LSST

eROSITA → WFXT/LOBSTER

UKIDSS → ?

all need massive efforts at automated, real-time data analysis andcoordination



GW counterparts

NS mergers:Rasio & Shapiro (1992)Rasio & Shapiro (1994)

Janka et al. (1999)

Anderson et al. (2008ab)...

Zhuge et al. (1994)Ruffert et al. (1996)

Faber & Rasio (2000)Faber & Rasio (2001)Shibata et al. (2003)

Analytic Newtonian hydro Relativistic hydro

Bloom et al. (2009)

O’Neill et al. (2009)Megevand et al. (2009)

Demorest et al. (2009)Jenet et al. (2009)Madau et al. (2009)Miller et al. (2009)Nandra et al. (2009)Owen (2009)

Phinney (2009)Prince (2009)Schutz et al. (2009)Stamatikos et al. (2009)

Astro 2010 white papers

Corrales et al. (2009)

MacFadyen & Milos. (2008)

Armitage & Natarajan (2002)Hayasaki et al. (2008)

Shields & Bonning (2008)JS & Krolik (2008)Lippai et al. (2008)Kocsis & Loeb (2008)Krolik (2010)Chang et al. (2009)

Anderson et al. (2010)

Palenzuela et al. (2009)Bode et al. (2009)van Meter et al. (2010)Farris et al. (2010)

Shapiro (2010)Haiman et al. (2010)Tanaka & Menou (2010)

Rossi et al. (2010) Palenzuela et al. (2010)Mosta et al. (2010)Zanotti et al. (2010)



Even small amount of gas leads to bright EM signal

energy content of gas dominated by gravitational potential:

Egas ∼ εΣR2 (ε ≈ 0.01− 0.1)

cooling time for optically thick gas:

tcool =τh

c∼ ε1/2ΣR3/2,

giving “universal” luminosity:

dL

d lnR≈ ε1/2R1/2LEdd ∼ 1044 M6 erg/s

Krolik (2010)



Test particle simulations ⇒ ultra-relativistic flows

234567

234567

Max

imum

Lor

entz

Fac

tor

-600 -500 -400 -300 -200 -100 0 100Time [M]

234567

Isolated, Nonrotating

Nonrotating, 5 orbits to merger

Rotating, 5 orbits to merger

10-5

10-4

10-3

10-2

IsolatedNonrotatingRotating

10-5

10-4

10-3

10-2

Frac

tion

of P

artic

les

with

Out

flows

γ >

γ c

-700 -600 -500 -400 -300 -200 -100 0 100Time [M]

10-5

10-4

10-3

10-2

γc = 1.2

γc = 1.4

γc = 1.5

10-510-410-310-210-1100

10-510-410-310-210-1100

Frac

tion

of P

artic

les

with

Out

flow

γ > γ c

10-510-410-310-210-1100

-700 -600 -500 -400 -300 -200 -100 0 100Time [M]

10-510-410-310-210-1100 Isolated

NonrotatingRotating

γc = 1.2

γc = 1.5

γc = 2

γc = 3

van Meter et al.(2010)



Hydro plus NR ⇒ strong shocks, heating

Bode et al.(2010)



Hydro plus NR ⇒ strong shocks, heating

Bode et al.(2010)



but just one question...



...will there be any gas?

circumbinary disk clears out a gap around the BHs:

MacFadyen & Milosavljevic (2008)

after disk decouples (tGW < tinflow), could be even less gas



Need grid-based 3D MHD simulations

−2 −1 0 1 2

−2

−1

0

1

2

−4

−3

−2

−1

0

t=300.5

Shi, Krolik, & Lubow (2011)



Clear periodic accretion

360 380 400 420 440 460 480t(Ωbin

−1 )

0.00

0.01

0.02

0.03

0.04

0.05

−dM

/dt(

(GM

a)1/

2 Σ 0)

0.5 1.0 1.5 2.0 2.5 3.0ω(Ωbin )

0.000

0.005

0.010

0.015

0.020

0.025

0.030

pow

er s

pect

ral d

ensi

ty

Shi, Krolik, & Lubow (2011)



Classical Lagrange points in restricted 3-body problem

µ2 = m2/M = 0.2 µ2 = m2/M = 0.02

µcrit ≈ 0.0385JS 2010



Applications

formation mechanisms:

tidal capture of GC+IMBHsupermassive star formation in accretion diskgas leaking from circumbinary diskIMBH+MS star

observables:

tidal disruption eventshyper-velocity starsenhanced star formationhighly-shifted emission linesaccretion burst prior to mergereffect on gravitational waveforms



Tidal disruption of stars during inspiral

Rtd,∗ = 2R∗(

MBHM∗

)1/3

M1 = 106M, µ2 = 1/50 M1 = 107M, µ2 = 1/50

0.01 0.10 1.00 10.00 100.00 1000.0010000.00days before merger

1011

1012

1013

1014

a (c

m)

Rtd, O/B

Rtd, sun

Rtd, WD

0.01 0.10 1.00 10.00 100.00 1000.0010000.00days before merger

1011

1012

1013

1014

a (c

m)

Rtd, O/B

Rtd, sun

Rtd, WD



What do we do next—theory

cosmological N-body plus hydro

high-resolution N-body simulations of galactic nuclei

Newtonian regime: grid-based code vs. geodesics/SPH

good initial conditions for circumbinary disk

full NR+MHD

radiation post-processing



What do we do next—observations

dual AGN: HST imaging, field integral spectroscopy

binary AGN: SDSS + long-term spectroscopic followups

pulsar timing: more pulsars, ∼ 10 ns resolution

afterglows: wide-field multi-band surveys

cores/star clusters: HST imaging + hires spectra

LISA counterparts/precursors: wide-field time domain surveys(Pan-STARRS, LSST, MAXI, WFXT, etc.)



Summary/Conclusions

EM signatures of BH mergers are valuable as:

Probes of strong-field GR (mass loss, kicks)

Probes of accretion disk properties

Cosmological observationsMBH, Mbulge, σbulge relationshipsgalaxy formation and evolutionSMBH growth (mergers vs. accretion)mass/spin distribution functions

PTA counterpartsnearby, massive, brightextensive follow-up on human timescales

LISA counterpartsdistance ladder in a single stepluminosity-redshift to . 1%

LIGO counterparts: GW confirmation



Discussion Questions

is there gas?

can we see it?


Documents

Black Hole Coalescence: The Gravitational Wave Driven Phasemctp/SciPrgPgs/events/2011/Blackholes/...Black Hole Coalescence: The Gravitational Wave Driven Phase Jeremy Schnittman Overview