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Do Intergalactic HI Clouds Exist ?

Do Intergalactic HI Clouds Exist ?. A recycled IGM talk from the IAU Symposium on Recycling the Intergalactic Medium. z = 8. z = 0. NEUTRAL Hydrogen. NO !. Do INTERGALACTIC HI CLOUDS exist ?. The Short Answer:. z = 8. z = 0. NEUTRAL Hydrogen. HI.

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Do Intergalactic HI Clouds Exist ?

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  1. Do Intergalactic HI Clouds Exist ? A recycled IGM talk from the IAU Symposium on Recycling the Intergalactic Medium z = 8 z = 0

  2. NEUTRAL Hydrogen NO ! Do INTERGALACTIC HI CLOUDS exist ? The Short Answer: z = 8 z = 0

  3. NEUTRAL Hydrogen HI INTERGALACTIC HI CLOUDS The Short Story: • definition … • why should they exist ? • why should they NOT exist?

  4. M82 M81 NGC 3077 HI Map of M81 Group Yun, Ho & Lo 1994

  5. HI Map of M81 Group Yun, Ho & Lo 1994 ??? INTERGALACTIC ?????? Pristine, Primordial gas !!?? NO STARS !!!???

  6. Fuel ongoing Star Formation Solve metal abundance problems…. Trace “dark” Dark Matter Halos HI Map of M81 Group Yun, Ho & Lo 1994 Pristine, Primordial gas ??

  7. more HI in M96 than the Ring (Schneider etal 1989)

  8. HI contours

  9. i.e. Cartoon for Z = 0 Sea of ionized baryons F ?? Just HI ?? Stars & HI gas

  10. Radio spectroscopy

  11. Giovanelli- Haynes “Virgo Cloud” Chengalur et al 1995 .

  12. Limits on I.G. HI Clouds: • Fisher & Tully “not cosmologically significant”

  13. Limits on I.G. HI Clouds: • Fisher & Tully “not cosmologically significant” • 1990 Briggs NIGClouds 1 • NGalaxies 100 <

  14. Limits on I.G. HI Clouds: • Fisher & Tully “not cosmologically significant” • 1990 Briggs NIGClouds 1 • NGalaxies 100 < 2000 Zwaan (PhD Thesis) HI Mass Function

  15. Limits on I.G.Clouds Arecibo: HI content according to galaxy mass (Zwaan et al 1997)

  16. Limits on I.G. HI Clouds: • Fisher & Tully “not cosmologically significant” • 1990 Briggs NIGClouds < 1 . • NGalaxies 100 • 2000 Zwaan (PhD Thesis) HI Mass Function • 2003 Koribalski/Zwaan ET AL… HIPASS

  17. HIPASS … Parkes Telescope Consortium: ATNF, Melbourne, Cardiff, RSAA +

  18. Limits on I.G. HI Clouds: • Fisher & Tully “not cosmologically significant” • 1990 Briggs NIGClouds < 1 . • NGalaxies 100 • 2000 Zwaan (PhD Thesis) HI Mass Function • 2003 Koribalski/Zwaan ET AL… HIPASS • 1000’s of galaxies… no I.G. Clouds

  19. MHI Msolar = 10 – 20 Loptical Lsolar HIPASS result… Warren, Jerjen, ET AL …. a few extremely HI rich galaxies ??? I.G. HI Clouds with stellar contamination ??? B.Warren: “They’re galaxies !”

  20. … that’s the observational evidence.

  21. CMB Big Bang Nucleosynthesis+WMAP .…. ionized……

  22. damped Lyman-a abs-lines 21cm Line Studies (HIPASS)

  23. W W M Tot -0.5 0 1/3300

  24. Recombination competes with Re-ionization

  25. = n /(n n a ) recomb e e p = 1 /( n a ) p recomb 1/2 -11 = T /( n 2 x 10) sec p 3 but, n~ n proportional ~ (1+z) p baryon 3 1/2 t proportional T /(1+z) recomb Time scales for Recombination in IGM… t = n /R recomb e

  26. Onset of sources of ionizing radiation Temperature vs Redshift Tcmb Tkinetic

  27. Temperature vs Redshift first ionizing sources H

  28. QSOs /AGN He Temperature vs Redshift first ionizing sources H

  29. low density Galaxy Disk Gas Trec ~ 105yr Tkinetic Recombination Time (mean density) 1010yr 109yr Age of Universe 107yr

  30. i.e. Hydrogen must be confined ! Z = 0 Sea of ionized baryons F ?? Just HI ?? Stars & HI gas

  31. Barkana & Loeb: Dark Matter Halo Mass Function Z = 30 20 10 50

  32. Integral Mass Content per logarithmic interval

  33. Mass Functions

  34. DM Clusters baryons Mass Functions

  35. Mass Functions

  36. Mass Functions

  37. Mass Functions Missing bound baryons

  38. i.e. If massive, get Z = 0 Fate of baryons in small halos…? Sea of ionized baryons F

  39. Z = 0 Fate of baryons in small halos… Sea of ionized baryons F • Early small halo formation… gas expelled by supernovae • Late small halo formation… IGM too hot to be captured by a low mass halo Mhalo ~108Mo => Tvir ~ 104.3 K

  40. Large mass halosStar Formation Galaxies Early Low mass halos Star Formation ISM Lost Late Low mass halos never capture gas, (No Star Formation) No Intergalactic Neutral Hydrogen Clouds at Z=0 … need to recover low metalicity IONIZED IGM & Halo clouds… Conclusions:

  41. NGC 1512: Color coded velocity field

  42. NGC 3344: HI Gas distribution

  43. NGC 3344: HI velocity field

  44. DLA (HI) CIV MgII/ Lyman limit (CII, FeII, SiII, …) Relative interception cross sections for QSO Absorption Lines …

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