1. The Effects of X-rays on Star Formation and Black Hole Growth in Young Galaxies Ayçin Aykutalp (Kapteyn), John Wise (Georgia), Rowin Meijerink (Kapteyn/Leiden) Marco Spaans (Kapteyn, Netherlands)

2. BHs  Many galaxies contain BHs : M BH ~10 -3 M bulge  Need accretion onto seed BHs and the formation of Pop III and PopII/I at early times  Even z~6 SMBHs of 10 9 M  exist  Possible evolution in Magorrian rel. at high z (Walter ea 04)  BHs produce UV and X-ray radiation: feedback  Seed BHs formed as remnants of Pop III stars or through singular collapse in primordial atomic cooling halos. The latter requires a strong UV background (10 3-5 J 21 ) and/or Lyman α trapping (Bromm & Loeb 03, Spaans & Silk 06, Shang ea 08, Dijsktra ea 08, Inayoshi & Omukai 12)

3. XDRs  σ ~ E -3 1keV  10 22 cm -2 penetration Secondary Ionizations Dominate  F X =84 L 44 r 100 -2 erg cm -2 s -1  X-ray flux over 1-100 keV with a power law E -0.9  think of a Seyfert AGN at 100 pc

4. E > 1 keV  Heating: X-ray photo-ionization  fast electrons; 10-50% H and H 2 vib excitation; UV emission (Ly α, Lyman-Werner)  Cooling: [FeII] 1.26, 1.64; [OI] 63; [CII] 158; [SiII] 35 μm; CO thermal H 2 vib; gas-dust  1 keV photon penetrates 10 22 cm -2 of N H

5. XDRs  Heating efficiency 10-50%  X-rays penetrate further than UV  High opacity of metal-rich gas  Large energy deposition rate (~F X /n H )  X-rays ionize and drive the ion-molecule chemistry, hence the H 2 formation

6. Simulations-1  Box size of 3 Mpc/h  3.6 pc proper resolution  Include X-ray chemistry by porting XDR code (Meijerink&Spaans 05): dust & ion-molecule chemistry, heating, cooling (escape probability for lines); pre- computed tables in n H, N H, F X, and Z/Z  (176 species, more than 1000 reactions)  Employ Moray (Wise et. al. 12) : UV and X-ray radiation transport (polychromatic spectrum) around the seed BH and every star particle  XDR (metallicity dependent) + Enzo non-equilibrium chemistry (9 species) run in parallel

7. Simulations-2  Consider singular collapse scenario for UV backgrounds of 10 3 J 21 and 10 5 J 21, which facilitate destruction of H 2 and suppresses fragmentation  Introduce seed BH M=5 x 10 4 M  at z=15  BH at 10% Eddington (Kim et. al. 11 prescrip.) produces UV (90%) and X-ray (10%)  Star formation recipes for Pop III (H 2 > 5 x 10 -4 ) and Pop II/I (Z > 10 -3.5 Z  ) from z=30  SN feedback, metal enrichment followed

8. Density-temperature (left) and column density-radius (right) profiles for zero and solar metallicity cases at z=14.95 (top) and z=14.54 (bottom). High opacity effect of metal enriched gas Solar Zero Solar

9. H 2 Fraction Low (10 3 J 21 ) and high (10 5 J 21 ) UV bg. cases at z=14.95 (left), 14.86 (middle), and 14.78 (right). Low High

10. Pop III stars Low UV bg, at z=14.95!!!

11. Metallicity z=14.78

12. Accretion rate  High UV bg case: 10 5 J 21  Low UV bg case: 10 3 J 21

13. BH growth Strong UV background prevents growth to a SMBH! X-ray feedback/BH growth self-regulating

14. X-ray Flux

15. X-ray flickering z=14.95 z=13.22 z=14.39 z=12.86 z=12.15 z=12.00

16. HII region High UV bg case, at z=12.86

17. Conclusions  X-rays important & metals boost X-ray opacity  heating  Weaker 10 3 J 21 UV background allows Pop III star formation and enrich the medium with metals  X-ray feedback/BH growth is self-regulating  Singular collapse scenario does not yield SMBHs at z=6 for 10 5 J 21 UV background  Interesting though for slowly evolving dwarfs today, unless there is later time UV weakening and/or metal enrichment  For low UV bg, 10 5 M  MBH grows at 10 -3 M  /yr, doubles in mass in Edd. time (usual suspects for SMBHs at z=6)

18. Discussion  3 Mpc/h box size: Merger rate, maximum halo mass underestimated  No Jets included  Self-shielding approximated locally  No UV background evolution  The simulations are still running!!!