1 / 20

DWARFS IN HIPASS AND SDSS

DWARFS IN HIPASS AND SDSS. Their properties merge smoothly with giants and show no extra Dark Matter. HOW MUCH GLOBAL INFORMATION/ GALAXY?. HOW MANY PHYSICAL PARAMETERS COULD CONTROL GALAXIES?

florence-holder
Download Presentation

DWARFS IN HIPASS AND SDSS

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. DWARFS IN HIPASS AND SDSS Their properties merge smoothly with giants and show no extra Dark Matter

  2. HOW MUCH GLOBAL INFORMATION/ GALAXY? • HOW MANY PHYSICAL PARAMETERS COULD CONTROL GALAXIES? • Total Mass, Baryon fract, Ang Mom,Radius, Concentration,Gas Mass,Age; ie SEVEN LESS 1 for Virial Theorem. Therefore SIX physical params. • HOW MANY INDEPENDENT OBSERVABLES CAN BE MEASURED? • Eg Lum, Radius, Concentration, M(HI), Internal Vel disp, Colour ……ie SIX too.

  3. Dwarfs v ClustersGilmore et al 2007

  4. M/L ratios in Dwarfs Gilmore 2007

  5. Montage of ES galaxies

  6. SB v Col Density

  7. HOW MUCH INDEPENDENCE? • We find 200 objects in HI Blind survey coincident with SDSS images and correlate all the following props:Lum, Colour, Radius,M(HI), R(90)/R(50), and M(dyn). • Each indep correl must reduce 6 independent variables by 1. • We find 5 correls (one new).Thus HI selected Galaxies form a ONE PARAMETER SET. • This is confirmed by Principal Component Analysis.

  8. Concentration v Mass

  9. HIMASS versus opt radius hdhdh

  10. Colour v Luminosity

  11. Mass v Luminosity

  12. SB versus Luminosity

  13. Dynamical Mass v R(cubed)

  14. Correlation plot for 5 variables, not including colour

  15. Principal Components for 5 variables, no colour

  16. Correlations between 6 variables including colour

  17. Principal components including colour

  18. Simulation.2 variables correlated, the third is random

  19. PCA of above. Note random varbl. has strong PC2

  20. OBSERVE THE REAL SKY • This high degree of organisation is totally inconsistent with Hierarchical galaxy Formation.(at least 4) and mergers. • Galaxy astronomers should look at their observations free of prejudices drawn from cosmological simulations which look increasingly misleading! • Observations of Galaxies contain far more reliable information about the process of Gal formation than numerical simulations.

More Related