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Accretion wake of recoiled black holes Roya Mohayaee CNRS, Institut d’Astrophysique de Paris Jacques Colin Observatoire de la C ô te d’Azur, Nice Joe Silk
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Accretion wake of recoiled black holes Roya Mohayaee CNRS, Institut d’Astrophysique de Paris Jacques Colin Observatoire de la Côte d’Azur, Nice Joe Silk University of Oxford astro-ph/07093321 J-P Lasota conference,Wroclaw 2007
Galaxy (black hole) mergers BHs at the centre of many galaxies Galaxy mergers BH mergers Emission of gravitational waves HST : colliding galaxies in Canis Major NGC 2207 –IC 2163 formation of a new centralBH
Black hole & dark matter Initially : initial ~ r- Adiabatic accretion: ffinal(Efinal,Lfinal) = finitial(Einitial,Linitial)
Black hole & dark matter (Young 1980, Gondolo & Silk 1999) Without BH : initial ~ r- With BH : final ~ r-(9-2)/(4-)
Absolute luminosity (L) of BH in -rays + L =luminosity factorx ∫2 dV /s luminosity factor =[N<v>/m2]c4/cm 3/s/Gev2 For M31: Fornasa et al 2007
Galaxy (black hole) mergers BHs at the centre of many galaxies Galaxy mergers BH mergers Emission of gravitational waves HST : colliding galaxies in Canis Major NGC 2207 –IC 2163 If isotropic formation of a new centralBH
Galaxy (black hole) mergers BHs at the centre of many galaxies Galaxy mergers BH mergers Emission of gravitational waves HST : colliding galaxies in Canis Major NGC 2207 –IC 2163 If isotropic If anisotropic Ejection of the BH From the galaxy formation of a new centralBH
Ejection of a black hole during galaxies mergers Spin=zero X=0.38
Ejection of a black hole during galaxies mergers spin ≠ 0 recoil velocity 4000 km/s Campanelli et al 2007
Orbit of an ejected BH high V~0 low high v Virial radius
Density profile of the accretion wake • Cold medium >Bondi-Hoyle accretion (1944) • Two-body problem +mass conservation V r (q) dq (x) dx=(q) dq
Density profile of the accretion wake hot medium (e.g. Maxwellian velocity distribution) > Danby & Camm (1957) V Jean’s theorem numerical solution for density Analytic solution for stationary BHs : (r)~ 1/√r
Wake density : hot versus cold medium Hot environment
Wake density : hot versus cold medium Hot environment Cold environment
Wake density contours Wake density contours,small
Highest density at the apapsis passage high V~0 low high v Virial radius
Time to reach the apapsis Initial velocity of BH / escape velocity
Absolute luminosity of a recoiled BH in -rays L(M,z) = [N<v>/m2] ∫2 dV /s L= 1025 (1+z)4 (M/Mo) R2cutoff /s LBH /Lhost galaxy
BH Mass function Press & Schechter (1974) Density peaks in initially random gaussian field collapse to form ‘‘galaxies’’ Number density of galaxies of mass M at redsift z N(M,z)
Diffused -ray background =H0 ∫∫t(M,z) L(M,z) N(M,z) dM dr(z) Time the BH spends at apapsis Press-Schechter mass function 1025 (1+z)4 (M/Mo) R2cutofff/s
Time spent at apapsis =H0 ∫∫ t(M,z) L(M,z) N(M,z) dM dr(z)
Future Prospects: Confronting the observations > 10 -8 cm-2 s-1 sr-1
Future Prospects: Confronting the observations > 10 -8 cm-2 s-1 sr-1 cm-2 s-1 sr-1 EGRET 10-7 GLAST 10-8 10-9 10-10 10-11 MAGIC 10-12 HESS, VERITAS