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Searching for Intermediate Mass Black Holes Searching for intermediate mass black holes Natalie Webb Institut de Recherche en Astrophysique et Planétologie Toulouse, France Natalie Webb 1 ULXs and their environments, June 2016 Context · Black holes : stellar mass, ~3-10s M ; supermassive, 10 6-10 M ⊙ ⊙ · Black holes proposed : intermediate mass, 10 2-5 M (IMBH) ⊙ expect ~90% of ~109 M ⊙ galaxies contain ~104 M ⊙ black holes today expect ~50% of ~109 M ⊙ galaxies contain > 105 M ⊙ black holes today (Greene, 2012) Natalie Webb 2 ULXs and their environments, June 2016 HLX-1 2XMM J011028.1-460421 (Farrell, Webb et al., Nature, 2009) ~8º from nucleus of ESO 243-49 (z=0.0224, ~95 Mpc) 42 -1 If associated with ESO 243-49 => Lx=1.1x10 erg s (0.2-10.0 keV) => from Eddington luminosity (LEdd), M = 5000 M⊙ Superceding LEdd by a factor 10 (Begelman 02) => M > 500 M⊙ Natalie Webb 3 ULXs and their environments, June 2016 HLX-1 Wiersema et al. (2010) Presence of Hα line confirmed by Soria et al. (2013) Lasota, King & Dubus (2015) question the distance to HLX-1 Does the system originate in ESO 243-49 or is it due to a merger ? Natalie Webb 4 ULXs and their environments, June 2016 HLX-1 Webb et al., Science (2012) 3 σ upper limit, Servillat et al. (2011) 8.2 σ, 45 μJy 21 μJy (5+9 GHz) Natalie Webb 5 ULXs and their environments, June 2016 HLX-1 ~1 yr ~1 yr ~1 yr ~1.12 yr ~1.25 yr >1.4 yr Natalie Webb ULXs and their environments, June 2016 HLX-1 2XMM J011028.1-460421 ~8º from nucleus of ESO 243-49 (z=0.0224, ~95 Mpc) V ~ 25.4 min V ~ 23.6 max R ~ 24.5 min R ~ 23.5 max Webb et al. (2014) Natalie Webb 7 ULXs and their environments, June 2016 HLX-1 Lasota et al. (2011) Orbital evolution . of polytropic companion, n=1.5, Γ=5/3. Initial periapsis separation X (relative to tidal radius) of 2.3 (red), 2.4 (magenta), 2.5 (blue), 2.7 (black), λ = R/0.01R⊙, 4 (Godet et al. 2014) M =M /10 M⊙ 4 BH Natalie Webb 8 ULXs and their environments, June 2016 MUSE observations of the environment of HLX-1 Crédit : CXO Webb et al. (2016) Natalie Webb 9 ULXs and their environments, June 2016 MUSE observations of ESO 243-49 Galaxy mass ~ 8.1 x 1010 M ⊙ Supermassive black hole mass ~ 1 x 108 M ⊙ No evidence for a recent collision/merger A rapidly spinning disc compared to slower bulge can indicate dry minor mergers in galaxy history, e.g. Arnold et al. (2014) Minor merger scenario (Webb et al. 2010, Mapelli et al. 2013) possible Younger, metal-poor halo, indicates little matter has been accretedCrédit : CXO& initial diskiness of galaxy is thus preserved Webb et al. (2016) Natalie Webb 10 ULXs and their environments, June 2016 HLX-1 Observations in low/hard state Hα line flux diminished by > factor 10 Confirms association of line with HLX-1 and thus distance to HLX-1 No radial velocity information due to faintness of line No other lines from HLX-1 to understand environment Crédit : CXO Webb et al. (2016) Natalie Webb 11 ULXs and their environments, June 2016 Other intermediate mass black holes From Earnshaw et al. (2016) M51a Spectrum : Г~1.5, L = 2.2x1038 - 5.1 x 1039 erg s-1 Crédit : CXO x Low frequency break in power spectrum => M < 1.6 x 103 M BH ⊙ Radio & X-ray fluxes (fundamental plane) => M < 3.5 x 104 M BH ⊙ Natalie Webb 12 ULXs and their environments, June 2016 Other intermediate mass black holes CXO J122518.6+144545 Heida, Jonker & Torres (2015) 182 Mpc Crédit : CXO Natalie Webb ULXs and their environments, June 2016 13 Other intermediate mass black holes Tidal disruption events (TDE) (Rees, Nature, 1988) Tidal radius inside black hole event horizon for masses > 108 M ~ ⊙ Observe TDE from lower mass BHs -5 -4 ~10 ± 10 event/gal./yr Crédit : CXO ~30 such events observed (Komossa 2015) Natalie Webb 14 ULXs and their environments, June 2016 Tidal disruption events Coincident with centre of IC 4765-f01-1504 at z=0.0353 Galaxy inactive Modelling the disc with kerrbb 4 6 ⇒ M ~ 6 x 10 ± 4 x10 M BH ⊙ Lin et al. (2011) N =0.74+0.70 x1021 cm-2 H -0.70 +3.9 ~ kT = 57.8 -3.9 eV +0.59 Γ = 3.71-0.59 Χ2 = 0.92 (115 dof) ν Crédit : CXO Natalie Webb 15 ULXs and their environments, June 2016 Tidal disruption events 2003 3.8 hr period from the galaxy J1231+11 Ho et al. (2011) estimate mass ~105 M ⊙ from narrow emisson lines 2005 No longer detectable with Swift If QPO is the low frequency type, 6 2005 M < 4 x10 M BH ⊙ Lin et al. (2013) z=0.42 (d~2.3 Gpc) If at Eddington in X1 Crédit : CXO => M ~ 1 x 105 M BH ⊙ Lin et al. (2016) Natalie Webb 16 ULXs and their environments, June 2016 Intermediate mass black holes in low mass galaxies Much work done by J. Greene & collaborators searching low mass tail of the SMBH mass-velocity dispersion and mass-bulge luminosity relations. Improvements to mass-spheroid luminosity relation (Graham & Scott, ©13) Red dots = (luminous) core-Sérsic galaxies blue circles = (intermediate-luminosity) Sérsic galaxies & bulges, open crosses = barred. Graham & Scott (2013) identified ~50 lower luminosity spheroids with AGN that have M < 105 M BH ~ ⊙ Investigated 17 candidates with X-ray/radio data and placed objects on black hole fundamental plane (Koliopanos et al. in prep.) Natalie Webb 17 ULXs and their environments, June 2016 Intermediate mass black holes in low mass galaxies P r e l i m i n a r y ULXs and their environments, June 2016 Natalie Webb ( Koliopanos et al. in prep. ) 18 Summary 2XMM J011028.1-460421 HLX-1~8º from is an nucleus excellent of ESO intermediate 243-49 (z=0.0224, mass black ~95 hole Mpc) (IMBH) candidate of 4 ~2x10 M ⊙ HLX-1 fuelled by tidal stripping of companion in a short lived, highly elliptical binary Distance and luminosity to HLX-1 confirmed by variability of Hα line contemporary wth the X-ray variability Other IMBH may also be detected if they tidally strip/disrupt a star Tidal disruption events may offer another way to locate new IMBHs Some low mass galaxies may well be home to IMBH Natalie Webb 19 ULXs and their environments, June 2016 Open questions.... 2XMM J011028.1-460421 Can~8º from we detect nucleus radial of ESO velocity 243-49 from (z=0.0224, HLX-1 to ~95 understand Mpc) the orbit ? Was HLX-1 born in ESO 243-49 or is it the result of a minor merger ? What is the nature of the environment around HLX-1 ? Require observations to constrain properties ...and simulations to understand the history of the galaxy What is the size and the distribution of the population of IMBHs ? - how are IMBH formed ? - how do IMBH evolve (mergers/accretion) ? Natalie Webb 20 ULXs and their environments, June 2016 Backup slides 2XMM J011028.1-460421 ~8º from nucleus of ESO 243-49 (z=0.0224, ~95 Mpc) Backup slides Natalie Webb 21 ULXs and their environments, June 2016 MUSE observations of ESO 243-49 Crédit : CXO Natalie Webb 22 ULXs and their environments, June 2016 Scott & Graham 2013 sample of 72 galaxies with reliable supermassive black hole masses derive the M bh-(host spheroid luminosity, L) relation Ks -band 2MASS data gives near-linear relation M bh∝ L 1.10 ± 0.20 Ks for the core-Sérsic spheroids thought to be built in additive dry merger events, relation M bh∝ L 2.73 ± 0.55 Ks for Sérsic spheroids from gas-rich processes. advocate that the near-linear M bh-L and M bh-M Spheroid relations at high masses may have arisen from additive dry merging of galaxies. new Sérsic M bh-L equations predict the masses of candidate intermediate mass black holes in almost 50 low-luminosity spheroids containing active galactic nuclei Crédit : CXO Natalie Webb 23 ULXs and their environments, June 2016 Graham & Scott (2013) (a) central velocity dispersion σ, (b) Ks-band host spheroid magnitude, and (c) B-band host spheroid magnitude. The red dots representCrédit the : CXO (luminous) core-Sérsic galaxies and the blue circles represent the (intermediate-luminosity) Sérsic galaxies and bulges, while the open crosses designate those which are barred. Natalie Webb 24 ULXs and their environments, June 2016 Scott & Graham 2013 Schematic showing the evolutionary path of "dry" galaxy mergers as they branch off from the steeper, near- quadratic, Mbh±L relation for Sérsic galaxies built from "wet" mergers and/or gas- rich processes. Crédit : CXO Natalie Webb 25 ULXs and their environments, June 2016 Scott & Graham 2013 Predicted Intermediate Mass Black Holes Galaxy log M_bh/M_sun NGC 3185 -20.80 -20.94 5.3 +or- 0.9 NGC 3593 -20.70 -21.03 5.4 +or- 0.9 NGC 3600 -19.20 -19.72 4.0 +or- 1.1 NGC 3729 -20.10 -20.24 4.6 +or- 1.0 NGC 4245 -20.80 -20.93 5.3 +or- 0.9 NGC 4314 -21.00 -21.11 5.5 +or- 0.9 NGC 4369 -20.90 -21.01 5.4 +or- 0.9 NGC 4470 -20.40 -20.53 4.9 +or- 1.0 NGC 3003 -19.60 -20.09 4.4 +or- 1.0 NGC 3043 -20.80 -21.17 5.6 +or- 0.9 NGC 3162 -20.00 -20.12 4.4 +or- 1.0 NGC 3344 -19.30 -19.41 3.7 +or- 1.1 NGC 3507 -20.90 -21.01 5.4 +or- 0.9 NGC 3684 -20.60 -20.74 5.1 +or- 1.0 NGC 3686 -20.60 -20.72 5.1 +or- 1.0 NGC 3756 -18.20 -18.43 2.6 +or- 1.3 IC 467 -19.20 -19.50 3.8 +or- 1.1 NGC 514 -19.90 -20.02 4.3 +or- 1.0 NGC 628 -20.40 -20.51 4.9 +or- 1.0 NGC 864 -19.90 -20.03 4.3 +or- 1.0 NGC 2276 -20.90 -21.01 5.4 +or- 0.9 NGC 2715 -19.20 -19.56 3.8 +or- 1.1 NGC 2770 -19.10 -19.50 3.8 +or- 1.1 NGC 2776 -20.90 -21.01 5.4 +or- 0.9 NGC 2967 -20.30 -20.41 4.8 +or- 1.0 NGC 3041 -19.90 -20.05 4.4 +or- 1.0 NGC 3198 -19.80 -20.11 4.4 +or- 1.0 NGC 3359 -20.80 -20.97 5.4 +or- 0.9 NGC 3430 -20.10 -20.29 4.6 +or- 1.0 NGC 3433 -20.40 -20.51 4.9 +or- 1.0 NGC 3486 -19.90 -20.03 4.3 +or- 1.0 NGC 3596 -21.00 -21.11 5.5 +or- 0.9 NGC 3666 -18.20 -18.63 2.8 +or- 1.2 Crédit : CXO NGC 3726 -20.10 -20.24 4.6 +or- 1.0 NGC 3780 -20.20 -20.32 4.7 +or- 1.0 NGC 3938 -20.50 -20.61 5.0 +or- 1.0 NGC 4062 -18.50 -18.78 3.0 +or- 1.2 NGC 4096 -19.40 -19.84 4.1 +or- 1.1 NGC 4136 -18.00 -18.11 2.2 +or- 1.3 NGC 4152 -20.80 -20.92 5.3 +or- 0.9 NGC 4212 -20.10 -20.27 4.6 +or- 1.0 Natalie Webb 26 ULXs and their environments, June 2016.
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