1 / 67

Simulating the ionisation and metal enrichment history of the Intergalactic Medium

Investigating the ionisation and metal enrichment history of the Intergalactic Medium using simulations and observational data.

robertoe
Télécharger la présentation

Simulating the ionisation and metal enrichment history of the Intergalactic Medium

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tom Theuns Institute for Computational Cosmology, Durham, UK Department of Physics, Antwerp, Belgium Simulating the ionisation and metal enrichment history of the Intergalactic Medium

  2. The LCDM paradigm WMAP et al + 2dF/Sloan et al Tom Theuns: IGM ionisation and enrichment

  3. How to go from to Tom Theuns: IGM ionisation and enrichment

  4. Semi-analytic galaxy formation and the large-scale galaxy distribution Durham incarnation Tom Theuns: IGM ionisation and enrichment

  5. Distribution of galaxies in 2dF GRS Tom Theuns: IGM ionisation and enrichment

  6. Distribution of galaxies in simulated 2dF GRS Tom Theuns: IGM ionisation and enrichment

  7. Simulations and the starformation history Springel & Hernquist 2003 Tom Theuns: IGM ionisation and enrichment

  8. Tom Theuns: IGM ionisation and enrichment

  9. Simulations and stellar archaeology Single galaxy and the importance of feedback Stars Gas Okamoto et al 05 Tom Theuns: IGM ionisation and enrichment

  10. Stellar Archeology: Harris & Zaritsky Tom Theuns: IGM ionisation and enrichment

  11. The importance of “feedback”: galaxy-wide winds? M82 Springel Tom Theuns: IGM ionisation and enrichment

  12. More evidence for super winds? Sauron observations of a Ly a ”blob” at z=3 Wilman et al 05 Tom Theuns: IGM ionisation and enrichment

  13. Lyman a profile suggests presence of “sheet” of neutral gas, expelled by an earlier superwind phase Wilman et al 05 Tom Theuns: IGM ionisation and enrichment

  14. Absorption lines of several (low-ionization state) transitions are off-set from the velocity of the stars by many 100s of km/s in cB58, a Lyman-break gal@z=3 Pettini et al Tom Theuns: IGM ionisation and enrichment

  15. A new ISM multi-phase implementation: use sticky particles to represent molecular clouds (with Craig Booth) M33 (UV) M33 (Visual ) Tom Theuns: IGM ionisation and enrichment

  16. Sticky particle scheme: (Craig Booth) • Thermal instability leads to cloud formation (McKee & Ostriker) • Small clouds coagulate to make more massive clouds • GMCs collapse after 10Myr, converting 10% of mass into stars • Stellar winds and Sne explosions destroy GMC (feedback) • Hot gas evaporates small clouds Nearly resolution independent! Tom Theuns: IGM ionisation and enrichment

  17. Tom Theuns: IGM ionisation and enrichment

  18. Star formation in a closed box F SFR T[K] Time Tom Theuns: IGM ionisation and enrichment

  19. Tom Theuns: IGM ionisation and enrichment

  20. … and in M33 Position of clouds formed in a collapsing rotating sphere Tom Theuns: IGM ionisation and enrichment

  21. Feedback from AGN X-ray observations of the Perseus galaxy clusters show hot cavities, plausibly inflated by AGN Chandra Tom Theuns: IGM ionisation and enrichment

  22. Buoyant bubbles from an AGN heating the gas and quench cooling (flow). Flash/AMR Tom Theuns: IGM ionisation and enrichment Della Vecchia

  23. Tom Theuns: IGM ionisation and enrichment

  24. Flash AMR code at Durham: • Radiative transfer (Crash) • Star formation and feedback • Gravity (fftw version) Tom Theuns: IGM ionisation and enrichment

  25. Investigate radiative transfer effects Maselli et al Tom Theuns: IGM ionisation and enrichment

  26. X-ray preheating from early black holes Kuhlen & Madau Tom Theuns: IGM ionisation and enrichment

  27. Simulated spectra look very similar to the data Mock versus Keck spectrum: which is which? Theuns Tom Theuns: IGM ionisation and enrichment

  28. Pixel Optical Depth Method Simulations look very realistic: use them to estimate contamination in interpreting metal optical depths, and to compute other sources of bias. Schaye et al, Aguirre et al. Tom Theuns: IGM ionisation and enrichment

  29. Metals (C IV) found to low densities. No obvious evolution with redshift. Galactic winds? Pop III Stars? Abundance redshift density Schaye et al 2003 Tom Theuns: IGM ionisation and enrichment

  30. Can feedback implementation explain observed metals? Simulation with metal enrichment due to galactic winds appears to reproduce the observed CIV-HI scatter Theuns et al 2001 Tom Theuns: IGM ionisation and enrichment

  31. The winds generated have little effect on the Lya forest Tom Theuns: IGM ionisation and enrichment

  32. But do reasonably well in reproducing the C IV lines Tom Theuns: IGM ionisation and enrichment

  33. NCarbon NHydrogen Tom Theuns: IGM ionisation and enrichment

  34. In simulations, there are a lot of metals in hot gas. Pixel Optical Depth analysis: C III/ C IV C IV Are the metals in the simulations too hot? Aguirre et al ‘05 Tom Theuns: IGM ionisation and enrichment

  35. Using QSO sightlines to probe density structure around galaxies and QSOs Tom Theuns: IGM ionisation and enrichment

  36. Adelberger et al 03 Tom Theuns: IGM ionisation and enrichment

  37. Density structure around QSOs and the proximity effect Fraction of pixels with given scaled optical depth, t = t0(z0) (1+z)a Rollinde et al 05 Tom Theuns: IGM ionisation and enrichment

  38. Rollinde et al 05 Tom Theuns: IGM ionisation and enrichment

  39. Lya forest becomes very dense at z>6: end of reionisation? Tom Theuns: IGM ionisation and enrichment

  40. What is evolution of ionizing background? Haardt & Madau ‘96 Tom Theuns: IGM ionisation and enrichment

  41. Galaxies must dominated G at z > 5 Estimate of G from simulations (diamonds) and inferrred from sources (triangles, squares) Bolton et al ’04 Jena et al ‘04 Tom Theuns: IGM ionisation and enrichment

  42. Bernardi et al 02 Theuns et al 02 Evidence for He II reionisation from Sloan Tom Theuns: IGM ionisation and enrichment

  43. IGM temperature as function of redshift. Schaye et al. Tom Theuns: IGM ionisation and enrichment

  44. If no other heat sources, HI reionization late? Theuns et al. Tom Theuns: IGM ionisation and enrichment

  45. Does reionization affect galaxy formation? Yes: Barkana & Loeb Tom Theuns: IGM ionisation and enrichment

  46. Does reionization affect galaxy formation? No: Benson et al Tom Theuns: IGM ionisation and enrichment

  47. Summary • Feedback • Reionisation • Ionising background. • First objects • Importance of AGN? Thank you Tom Theuns: IGM ionisation and enrichment

  48. Tom Theuns: IGM ionisation and enrichment

  49. Tom Theuns: IGM ionisation and enrichment

  50. 2. Numerical simulations: c) photo-ionisation Tom Theuns: IGM ionisation and enrichment

More Related