1. THE LYMAN-  FOREST AS A PROBE OF FUNDAMENTAL PHYSICS MATTEO VIEL Shanghai, 16 March 2005 1.Cosmological significance of the Lyman-  forest 2. LUQAS: The observational sample 3.Hydro-dynamical simulations of the Lyman-  forest 4.Cosmological parameters – Implications for: inflation, neutrinos, gravitinos, warm dark matter particles With M. Haehnelt, J. Lesgourgues, S. Matarrese, A. Riotto, V. Springel, J. Weller

2. GOAL: the primordial dark matter power spectrum Tegmark & Zaldarriaga 2002 CMB physics z = 1100 dynamics Ly  physics z < 6 dynamics + termodynamics CMB + Lyman  Long lever arm Constrain spectral index and shape Relation: P FLUX (k) - P MATTER (k) ?? Continuum fitting Temperature, metals, noise

3. before WMAP Croft et al. 2002 WMAP Verde et al. 2003 the WMAP era Tilt in the spectrum n<1 ? Running spectral index dn/dlnk < 0 ?

4. DM STARS GAS NEUTRAL HYDROGEN  m = 0.26   = 0.74  b =0.0463 H = 72 km/sec/Mpc - 60 Mpc/h COSMOS computer – DAMTP (Cambridge)

5. The LUQAS sample -I Kim, MV, Haehnelt, Carswell, Cristiani, 2004, MNRAS, 347, 355 Large sample Uves Qso Absorption Spectra (LP-UVES program P.I. J. Bergeron) high resolution 0.05 Angstrom, high S/N > 50 low redshift, =2.25,  z = 13.75 Nr. spectra redshift

6. The LUQAS sample –II systematic errors Effective optical depth = exp (-  eff ) Power spectrum of F/ Low resolution SDSS like spectra High resolution UVES like spectra

7. Hydro-simulations: scalings T = T 0 ( 1 +  )  Effective optical depth P FLUX (k) = b 2 (k) P MATTER (k) Viel, Haehnelt, Springel, MNRAS, 2004, 354, 684

8. Hydro-simulations: what have we learnt? Many uncertainties which contribute more or less equally (statistical error is not an issue!) Statistical error4% Systematic errors~ 15 %  eff (z=2.125)=0.17 ± 0.02 8 %  eff (z=2.72) = 0.305 ± 0.030 7 %  = 1.3 ± 0.3 4 % T 0 = 15000 ± 10000 K 3 % Method5 % Numerical simulations8 % Further uncertainties5 % ERRORS CONTRIBUTION TO FLUCT. AMPL.

9. Cosmological implications: combining the forest data with CMB - I n = 1.01 ± 0.02 ± 0.06  8 = 0.93 ± 0.03 ± 0.09 Statistical error Systematic error SDSS Seljak et al. 2004 MV, Haehnelt, Springel 2004 Note that the flux bispectrum analysis agrees with these values MV, Matarrese, Heavens, Haehnelt, Kim, Springel, Hernquist, 2004

10. Cosmological implications: combining the forest data with CMB - II SDSS Seljak et al. 2004  8 = 0.93 ± 0.07 n=0.99 ± 0.03  8 = 0.90 ± 0.03 n=0.98 ± 0.02 n run = -0.003 ± 0.010 n run =-0.033± 0.025 d n s / d ln k MV, Weller, Haehnelt, MNRAS, 2004, 355, L23

11. Cosmological implications: constraints on slow-roll inflation - III SDSS Seljak et al. 2004 r < 0.45 (95% lim.) r = 0.50 ± 0.30 No evidence for gravity waves T/S = T/S V = inflaton potential MV, Weller, Haehnelt, MNRAS, 2004, 355, L23

12. Cosmological implications: Warm Dark Matter particles-I  CDM WDM 0.5 keV 30 comoving Mpc/h z=3 MV, Lesgourgues, Haehnelt, Matarrese, Riotto, PRD in press k FS ~ 5 T v /T x (m x /1keV) Mpc -1 k FS ~ 1.5 (m x /100eV) h/Mpc In general if light gravitinos Set by relativistic degrees of freedom at decoupling

13. Cosmological implications: Warm Dark Matter particles-II  WDM  CWDM (gravitino like) Set limits on the scale of Supersymmetry breaking   susy < 260 TeV m WDM > 550 eV > 2keV sterile neutrino < 16 eV gravitino Scale of free streaming  gravitino /  DM

14. Cosmological implications: constraints on neutrinos  m (eV) = 0.33 ± 0.27 WMAP + 2dF + Lyman- 

15. HPM simulations of the forest Full hydro 200^3 part. HPM PMGRID=600 HPM PMGRID=400 FLUX POWER

16. HIGH RESOLUTION HIGH S/N vs LOW RESOLUTION LOW S/N

17. LUQAS vs SDSS

18. SUMMARY 1.LUQAS: a unique high resolution view on the Universe at z=2.1 2. Hydro-dynamical simulations of the Lyman-  forest. Systematic Errors? Differences between hydro codes? 3.Cosmological parameters: no fancy things going on  8 = 0.93 n = 1 no running substantial agreement between SDSS and LUQAS but SDSS has smaller error bars not because of the larger sample but because of the different theoretical modelling Constraints on inflationary models, neutrinos and WDM

19. HPM simulations of the forest-I Gnedin & Hui 1998 equation of motion for gas element if T = T 0 ( 1 +  ) 

20. Density Temperature No FeedbackFeedback Feedback effects: Galactic winds

21. Feedback effects: Galactic winds-III Line widths distribution Column density distribution function

22. Metal enrichment CIV systems at z=3 Strong Feedback  =1 ---- Role of the UV background Soft background ---- Role of different feedback  =1  =0  =0.1 Mori, Ferrara, Madau 2000; Rauch, Haehnelt, Steinmetz 1996; Schaye et al. 2003

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