DARK MATTER PROBES OF SUPERMASSIVE BLACK HOLES

HotSci 23 July 2014

Joe Silk (IAP, JHU)

SMBH binaries in quasars may be commonat parsec scales,from Balmer line offsets

Liu e al 2013

Stuck at the final parsec…Benson 2014

Mpc

IMBH EXPEL BARYONSTwo baryon problems:Too big to fail dwarfs & low baryon fraction in massive galaxies

Intermediate mass BH 103-106 Msun

Inoue + 2013

supernovae

IMBH

Baryon fraction fraction

Peirani + 2012Boylan-Kirchin et al. 2011

predicted hosts,not observed

Duc + 2013

Dubois+ 2013

Gondolo + JS 1999, Gnedin & Primack 2004, Sadeghian, Ferrer + Will 2013

<v>

mxPlateau: nx(r)<sv> tBH ~ 1Density profile

Vasiliev & Zelnikov 2008

tr (GC,M31)~3Gyr

but SMBH at GC grows over 1 Gyr& tr (M87 SMBH)~105Gyr!

~tr

~3tr

Does cusp survive? MAYBE!

NEAR BINARY BLACK HOLES

Kozai mechanism drives resonant infall of DM in eccentric orbits………operates for binary black hole

Naoz and Silk 2014

Naoz and Silk 2014 Dark matter torus forms

supermassive black hole at Galactic Center HESS J1745-290 prediction for CTA: superexponential signature of TeV DM annihilations

Belikov & JS 2013

Vaiana + 2014

30-300 GeV

the near future

NEARBY AGN

M87 is an attractive target

Distance 2000 x GC but MBH 1000 x SagA*

Flux ~ nx2<sv> (2rp)3 ~ MBH

3/<sv> for low <sv> nx(rp)<sv> tBH ~ 1

Dynamical heating of spike ~ 1014 yr vs 109 yr (GC)

Gorchtein et al 2010

Gomez et al 2013

M87

CenA

relativistic jets emanate from ergosphere, so high energy e,p collide with DM spike particles!

EXTRAGALACTIC GAMMA RAY BACKGROUND

There is room for an exotic component from dark matter

EXTRACALACTIC DIFFUSE g RAY BACKGROUND

10 TeV

1 TeV

0.1 TeV

NFW

Belikov & Silk 2013

Annihilations In dark matter spikes around supermassive black holes

THE ULTIMATE PARTICLE ACCELERATOR: dark matter cusp around black hole

particle horizon

Schwarzschild

BLACK HOLES

maximum 4.5 m

NEAR KERRBLACK HOLES

ergosphere Penrose process

particle horizonrS=2GM/c2

Banados, West, JS 2009

Highly controversial…but the dust hasn’t settled yet!

Kerr black hole

near event-horizon particle collisionsof KK particles: excitations

Arina, Bringmann, Vollmann, JS 2014

Rotating black hole can feed Penrose effect via DM particle collisions

no maximumfor extremal Kerr!

Black hole shadow

Event Horizon Telescope

Simulated image at 1mmof M87 or SagA* black hole

Resolve horizon scale GM/c2 at ~5 m arcsec

Huang + 2007

M87 distance 2000 x GC but MBH 1000 x SagA*