A.Klypin. Dark Matter Halos

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1 A.Klypin Dark Matter Halos 1

2 Major codes: GADET N-body Hydro Cooling/Heating/SF Metal enrichment Radiative transfer Multistepping/Multiple masses Springel, SDM White PKDGRAV - GASOLINE ART ENZO Quinn, Steidel, Wadsley, Governato, Moore Kravtsov, Klypin, N.Gnedin, Gottlober Bryan, Norman 2 2

3 Non-linear evolution: from Zeldovich approximation to DM halos 3 3

4 Non-linear evolution: from Zeldovich approximation to DM halos 3 3

5 Non-linear evolution: from Zeldovich approximation to DM halos 3 3

6 4 4

7 5 5

8 6 6

9 Local Group:z=0 7 7

10 Local Group:z=1 8 8

11 Local Group:z=7 9 9

12 Mass function of distinct halos 10 10

13 Mass function of distinct halos It started long ago: 32 years to be precise Now we live through 5th generation of this

14 Mass function of distinct halos It started long ago: 32 years to be precise Warren etal 2005: 13 sims each with 1G particles Now we live through 5th generation of this

15 Mass function of distinct halos It started long ago: 32 years to be precise Warren etal 2005: 13 sims each with 1G particles Now we live through 5th generation of this

16 Halo Mass Function depends on environment Sheth&Tormen 2002 GottlÖber etal

17 Clustering: DM halos and L Conroy, Wechsler, Kravtsov (2005): N-body only Get all halos from high-res simulation Use maximum circular velocity (NOT mass) For subhalos use Vmax before they became subhalos Every halo (or subhalo) is a galaxy Every halo has luminosity: LF is as in SDSS No cooling or major mergers and such. Only DM halos Reproduces most of the observed clustering of galaxies 12 12

18 SDSS: z=0 DM galaxies DM SDSS 13 13

19 DEEP: z=

20 Dark Matter and Galaxies 15 15

21 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson 15 15

22 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson 15 15

23 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson - Morphology-density relation: morphology is mostly defined by halo mass

24 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson - Morphology-density relation: morphology is mostly defined by halo mass. - Environment (how many neighbors) is just an indicator of halo mass 15 15

25 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson - Morphology-density relation: morphology is mostly defined by halo mass. - Environment (how many neighbors) is just an indicator of halo mass 15 15

26 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson - Morphology-density relation: morphology is mostly defined by halo mass. - Environment (how many neighbors) is just an indicator of halo mass Young etal(2003-5), Berrier etal(2005) : Halo occupation distribution the same conclutions 15 15

27 Dark Matter and Galaxies - Central DM closely correlates with L: Tully- Fisher, Faber-Jackson - Morphology-density relation: morphology is mostly defined by halo mass. - Environment (how many neighbors) is just an indicator of halo mass Young etal(2003-5), Berrier etal(2005) : Halo occupation distribution the same conclutions 15 15

28 Cusps: simulations Diemand etal

29 Tasitsiomi etal 2004 Navarro etal 2004 Slope gets shallower with decreasing radius, but it does not go below -1 Consistent with what other groups found 17 17

30 18 18

31 Profiles are NFW NOT NFW ρ(r)=ρo exp(-2nr 1/n )+<ρ> n=6-8 3D Sersic Navarro etal 2004 Merritt, Navarro 2004 Prada etal 2005 NFW 19 19

32 Average profiles of Milky Way-size halos 20 20

33 Infall velocities on halos of different mass Prada et al

34 RMS velocity of isolated halos Full: simulations Dash: solution of Jeans equation 22 22

35 SDSS and LCDM: surface number density of satellites around isolated galaxies 23 23

36 SDSS and LCDM: surface number density of satellites around isolated galaxies LCDM 23 23

37 Evolution of Halo structure Most of the accreted mass stays in the outer region of halo. Diemand etal

38 Evolution of Halo structure Dwarf Halos at high z cusp evolves very little. Colin etal

39 Halo Concentrations Bullock etal

40 Patiri et al 2006: SDSS Voids R>10Mpc 27 27

41 Number-density Profiles of Voids: n(r)/<n> Patiri et al 2006 SDSS LCDM 28 28

42 DM in central parts of galaxies Adiabatic compression: old approximation Adiabatic compression: Gnedin etal

43 How it works 30

44 Structure of our Galaxy Prada etal

halo formation in peaks halo bias if halos are formed without regard to the underlying density, then δn h n h halo bias in simulations

halo formation in peaks halo bias if halos are formed without regard to the underlying density, then δn h n h halo bias in simulations Physics 463, Spring 07 Bias, the Halo Model & Halo Occupation Statistics Lecture 8 Halo Bias the matter distribution is highly clustered. halos form at the peaks of this distribution 3 2 1 0 halo formation