Large Scale Structure of the Universe at high redshifts

1. Large Scale Structureof the Universeat high redshifts M.Demianski,A.Doroshkevich and S.Gottloeber

2. LSS at small redshifts – luminous matter

3. Ly- forest-LSS in DM & barions • Three characteristics of absorber Redshift – z Width - b km/s Depth - NHIcm-2 and UV background

4. Cosmological model

5. Properties of ~6000 absorbers 1015cm-2 >NHI > 1012cm-2

6. Metal systems (CIV)

7. Properties of observed LSS

8. PUZZLES • 1. Weak redshift dependence of the PDFs, P(b/<b>), P(NHI/<NHI>), P(dsep/<dsep>) • 2. <b>=const.(z), b < bbg • 3. Slow regular redshift variations of <NHI> ~(1+z)2 and <dsep>~(1+z)-2

9. DM simulation • Lbox =150h-1Mpc, Np= 2563 , Lcell=0.6h-1Mpc • Mass resolution: 2 107Mo, • Force resolution: 20h-1kpc, • Selected clusters: 10 < Np < 5000, =1.76

10. For colder clusters Np~<Np>/3 For hotter clusters Np~3<Np> Relaxation: frel~0.6-0.8 Simulated clusters

11. Core-sampling approachLcore=0.5h-1Mpc

12. Conclusions

13. Probable causes of self similarity • Deterministic character of simulations: all structure properties are determined by the initial power spectrum. • Zeldovich’ approximation • ri=(1+z)-1[qi-B(z) Si(q)] • Power spectrum • P(k)~k-3, k/k0> 1, k0~0.15Mpc-1

14. Real and simulated BBKS power spectrum

15. The end

16. Possible interpretation • <b>=const(z), W(xi)=const(z) • <dsep/(1+z)>~(1+z)-3~1/<nabsSabs> • Version 1 – relaxed clouds • nabs~(1+z)3, Sabs~const. • BUT <NHI>~(1+z)2 • Version 2 -- expanded clouds • Sabs~(1+z)-p, nabs~(1+z)3+p • BUT <b>=const., W(xi)=const(z)

17. Comparison with simulations. Lbox=100 h-1Mpc, Np=(256)3 , Lcell=0.4Mpc • Z=0, 1, 1.5, 2, 2.5, 3, 4, 5 • Two populations of clouds, and • Strongly deterministic approach • Previously – relaxed halos only • (galaxies, clusters of galaxies)

18. 60 Mpc/h

23. PDFs for cloud velocities, W(U), mass function, W(M), and surface density, W(q)

24. PDFs for three principle sizes of clouds, L, w, h

25. PDFs for the velocity dispersionsalong three principle axes of clouds

26. Mean characteristics High density clouds, L~ (1+z)1/4, w~ (1+z)1/2, h~(1+z)1/2 Vh~ (1+z)-1/2. Low density clouds, L~w~h~ const(z) Vh~ const(z). Cores and envelopes

27. Measured power spectrum

28. Problems and prospects • 1. Ly-ά emitters and population of earlier galaxies (~20 000 LBG) • 2. DM compact objects • 3. First luminous objects - stars or galaxies • 4. Spatial distribution of metal systems – bubbles ~2Mpc

29. DM simulation • Lbox =150h-1Mpc, Np= 2563 • Mass resolution 2 107Mo, Force resolution 20kpc/h • Selected clusters: 10 < Np < 5000, > 1.7 • Mean comoving principal sizes: • L~0.5h-1Mpc, W~0.2h-1Mpc, S~0.1h-1Mpc • Velocity dispersions along principal directions:

30. Z~2 - 3 • Lgal ~1026 erg/s/Hz/Mpc3 Giavalisco et al. 2004, GOODS, • LQSO~1023 – 1024 erg/s/Hz/Mpc3,

31. Next Steps • Detailed analysis of evolution of the Universe. • Properties of DM particles (composition, masses, stability). • Shape of the small scale initial power spectrum at L<100 kpc. • Galaxy and quasar formation. • Reheating and reionization of the Universe. • Etc….

32. Real and simulated power spectrum

33. Period of reionization

37. Metal systems (CIV)