1. Growing black holes: from the first seeds to AGN Mar Mezcua Harvard-Smithsonian Center for Astrophysics T. Miyaji, F. Civano, G. Fabbiano, M. Karouzos, A.P. Lobanov, T. Miyaji, T.P. Roberts, H. Suh, A.D. Sutton Picture credit: NASA

2. Black hole seeds Mar Mezcua The seeds of supermassive black holes Quasars of 10 10 M  when Universe was < 1 Gyr Had to start as seed BHs of 100 – 10 6 M  Grow fast via accretion and mergers Wu et al. (2015) Volonteri (2012) Artist’s conception of z≈7 quasar ESO Merloni et al. (2003) Falcke, Körding & Markoff (2004) Gültekin et al. (2009, 2014) Fundamental plane of BH accretion sub-Eddington accretion rates low/hard state core radio emission Intermediate-mass black holes of 100 – 10 6 M  Accretion physics is scale invariant

3. 1. Ultraluminous X-ray sources (ULXs) - Extragalactic, off-nuclear, L X > L Eddington for a stellar-mass BH (L X > 10 39 erg/s for a 10 M  BH) - Extreme ULXs with L X > 5 x 10 40 erg/s Most are super-Eddington accreting stellar-mass BHs? Black hole seeds: ULXs Mar Mezcua IMBHs with M BH ~ 100 - 10 6 M  Where can we find IMBHs? ESO 243-49 HLX-1 L X ~ 10 42 erg/s (Farrell et al. 2009) Transient jet radio emission  9·10 3 M  < M BH < 9·10 4 M  (Webb et al. 2012; Cseh et al. 2015) Nucleus of stripped satellite galaxy HLX-1 HST+ATCA 5-9 GHZ Webb et al. 2012

4. Extreme ULX NGC2276-3c L X ~ 6 x 10 40 erg/s (Sutton et al. 2012) Jet radio emission: -VLA lobes: size ~ 650 pc -EVN: 1.8 pc jet M BH ~ 3.9 x 10 5 M  (Mezcua et al. 2013c, 2015) Nucleus of stripped satellite galaxy Black hole seeds: ULXs Mar Mezcua EVN 1.6 GHz HST+Chandra composite NASA/CXC/SAO/INAF Mezcua et al. 2015, Wolter et al. 2015 Search for seed BHs in satellite, low-mass galaxies Search for seed BHs in satellite, low-mass galaxies

5. 2. Nucleus of dwarf, low-mass galaxies Resemble the first galaxies formed in the early Universe (low mass, low metallicity) - Optically-selected samples of AGN with broad emission lines  M BH = 10 5 -10 6 M  ~50 X-ray detected: L x = 10 41 - 10 43 erg/s Bias toward high Eddington ratios (> 10 -2 ) - X-ray detected low-mass galaxies, M * < 3 x 10 9 M  38 sources (Schramm et al. 2013, Lemons et al. 2015, Gallo et al. 2010, Miller et al. 2012, 2015) L x < 10 41 erg/s Edd. ratio < 10 -2 z < 0.3 Greene & Ho 2004, 2007; Reines et al. 2013; Desroches et al. 2009; Dong et al. 2012 Black hole seeds: low-mass galaxies Mar Mezcua Extend to higher z, complete samples Derive BH occupation fraction Extend to higher z, complete samples Derive BH occupation fraction

6. Black hole seeds: low-mass galaxies Mar Mezcua Formation & Evolution of seed BHs Low fraction of IMBHs in local dwarf galaxies High fraction of IMBHs in local dwarf galaxies Greene (Nature Communications, 2012)

7. Black hole seeds: low-mass galaxies Mar Mezcua Chandra COSMOS Legacy Survey 2.2 deg 2 covered by Chandra & HST Largest survey with complete, deep, multiwavelength dataset: XMM-Newton, NuSTAR, CFHT, Galex UV, Spitzer mid-IR, IRAC, Herschel, UKIRT NIR, Subaru multicolor imaging, optical spectra (Magellan, VLT, Keck), VLA radio imaging… K-band sensitivity limit = 23.7+-0.1 mag 2-7 keV flux limit = 1.7 x 10 -15 erg/s/cm 2 I-band (HST/F814W) depth = 27.8 mag Chandra Courtesy of F. Civano Multiwavelength SED, galaxy templates  stellar mass, star formation rate, redshift, morphology Ilbert et al. 2009; McCracken et al. 2012

8. Black hole seeds: low-mass galaxies in COSMOS Mar Mezcua Select low-mass galaxies as: - i < 24 mag - 10 7 < M * < 3 x 10 9 M  Low-mass galaxies in COSMOS 52,508 sources K-band sensitivity limit ~ 23 mag < 1% X-ray detected Mezcua et al. submitted

9. Black hole seeds: X-ray stacked low-mass galaxies in COSMOS Mar Mezcua 1. Morphological classification Low-mass galaxies dominated by starburst and spiral hosts  X-ray contribution from X-ray binaries and hot ISM gas Accreting BHs in early-type galaxies known Miller et al. 2012; Civano et al. 2014; Paggi et al. 2015 ✔ Population of accreting BHs in starburst and late-type galaxies ? Study 50,285 starburst+spiral galaxies Mezcua et al. submitted

10. Non-detections: stacking analysis Black hole seeds: X-ray stacked low-mass galaxies in COSMOS Mar Mezcua Select complete redshift bins  stack Chandra images for each bin with CSTACK Soft band (0.5-2 keV) Hard band (2-8 keV)  Count rate  Bootstrapping error analysis  Significant: S/N > 3  Flux conversion N H = 2.6 x 10 20 cm -2 Γ= 1.4 (Takamitsu Miyaji) Mezcua et al. submitted

11. Black hole seeds: X-ray stacked low-mass galaxies in COSMOS Mar Mezcua 2. Contribution XRBs L X,XRB α M * -SFR (Lehmer et al. 2010) M * and SFR  expected L X,XRB L X > L X,XRBs in all X-ray stacked redshift bins Mezcua et al. submitted

12. Black hole seeds: X-ray stacked low-mass galaxies in COSMOS Mar Mezcua 3. Nuclear L X vs stellar mass L X – L X,XRBs – L X,hot gas  X-ray excess!!! Must be nuclear L X – L X,XRBs – L X,hot gas  X-ray excess!!! Must be nuclear Mezcua et al. submitted

13. Black hole seeds: X-ray stacked low-mass galaxies in COSMOS Mar Mezcua 4. Eddington ratio and M bh – M * If L X /L edd ≥ 10 -2  low-mass galaxies off the M bh -M *  M bh ≤ 10 4 M  Greene 2012 Low-mass galaxies on the M bh -M * if L X /L edd ≤ 10 -6  M bh ≤ 6 x 10 6 M 

14. 5. Low-mass galaxies in mergers Mergers selected as neighbors with Δv ≤ 1000 km/s At z < 0.05  10.1 % of minor mergers 1.6% of the low-mass galaxies are in minor mergers 150.71405 +2.786401 z = 0.0051 149.912802 +2.304003 z = 0.005 HST cutouts Black hole seeds: X-ray stacked low-mass galaxies in COSMOS Mar Mezcua

15. Conclusions At low z, extend search for IMBHs to: - arm of spiral galaxies - galaxies undergoing a minor merger Black hole seeds Mar Mezcua Population of low-mass starburst and spiral galaxies with accreting BHs: - up to z=1.5 - more significant for z < 0.5 - M BH in the IMBH regime for Edd. ratio ≥ 10 -2 - galaxies on the M BH -M * correlation if Edd. ratio ≤ 10 -6  M BH ≤ 10 6 M  If they undergo minor mergers  detected as ULXs (nucleus of stripped galaxy) e.g. ESO 243-49 HLX-1, NGC 2276-3c Jet radio emission!!

16. WEBSITE: www.iac.es/galeria/mmezcua @marmezcua_astro