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Integrated Sachs-Wolfe effect with LOFAR

Integrated Sachs-Wolfe effect with LOFAR. Alvise Raccanelli Institute of Cosmology and Gravitaton. LOFAR Cosmology workgroup: M. Jarvis, W. Percival, D. Bacon, S. Rawlings, F. Abdalla. Outline:. The ISW effect Why the ISW is a good test for cosmological models Recent Results

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Integrated Sachs-Wolfe effect with LOFAR

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  1. Integrated Sachs-Wolfe effect with LOFAR Alvise Raccanelli Institute of Cosmology and Gravitaton LOFAR Cosmology workgroup: M. Jarvis, W. Percival, D. Bacon, S. Rawlings, F. Abdalla

  2. Outline: • The ISW effect • Why the ISW is a good test for cosmological models • Recent Results • Preliminary LOFAR Results LOFAR Workshop 9/03/2010 2 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  3. After the Big Bang, the Universe was hot and dense, and photons were strongly coupled to electrons and protons Hu & White 2004 3 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  4. The Universe is hot and dense Before the recombination, photons are coupled with matter, so they can not travel to us 4 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  5. The Universe become colder and less dense, and at one point protons and electrons form hydrogen (recombination) After the recombination, photons are free to travel towards us 5 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  6. 6 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  7. Galaxies form inside gravitational wells left after inflation 7 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  8. Travelling from the last scattering surface to us, photons pass through gravitational wells. If the potential is static, they will exit with the same energy they had when they entered. If the well is stretched by the dark energy, photons will experience a shift in energy (and so in temperature) 8 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  9. 9 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  10. But this effect is small compared to other CMB anisotropies 10 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  11. so we need to cross-correlate this temperature shift with something that can trace potential wells. Galaxies are a biased tracer of potential wells 11 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  12. 12 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  13. This part tells us where is matter bias growth factor redshift distribution of sources 13 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  14. This part tells us how the gravitational potential evolve evolution of the gravitational potential 14 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  15. ISW can be used to test the gravitational or the galaxies part: • Changing the filter of the galaxies allows us to test models for the bias relating the visible matter to the mass and the distribution of galaxies • Changing the filter of the gravitational part allows us to test models of gravity 15 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  16. Recent results: Testing Galaxy distribution and bias models (AR, A. Bonaldi, M. Negrello, S. Matarrese, G. Tormen, G. De Zotti) Raccanelli et al. 08 16 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  17. Recent results: Testing new Galaxy distribution models (M. Massardi, A. Bonaldi, M. Negrello, S. Ricciardi, AR, G. De Zotti) Massardi et al. 10 17 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  18. Recent results: With samples centered at higher redshift we can test early dark energy models J.Q. Xia et al. 09 18 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  19. Recent results: ISW effect with UDM models (D. Bertacca, AR, O. Piattella, S. Matarrese, N. Bartolo, D. Pietrobon, T. Giannantonio, in preparation) Kobayashi et al. 09 19 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  20. Recent results: ISW effect with Galileon and DGP models Giannantonio et al. 08 Kobayashi et al. 09 20 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  21. ISW with LOFAR With LOFAR we can have areas as wide as current surveys, but with more sources at all redshifts. The MSSS and the LOFAR Surveys "Tier-1" 120MHz survey will provide deep radio maps over the whole northern hemisphere with which to measure the ISW effect and thus constrain cosmological models (M. Jarvis and D. Bacon, LOFAR Cosmology workgroup proposal) 21 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  22. Preliminary results: Redshift Distributions from LOFAR simulations 22 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  23. Preliminary results: Redshift Distributions from LOFAR simulations compared with models previously used 23 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  24. Preliminary results: Predicted Cross-Correlation Function for MS3 and Deep 120MHz, compared with Pure Luminosity Evolution model 24 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  25. Preliminary results: Predicted Cross-Correlation Function for MS3, Deep 120MHz, compared with Pure Luminosity Evolution model and observed CCF from NVSS-WMAP5, assuming a constant bias = 1.7 25 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  26. Conclusions • The ISW is a good probe for testing different cosmologies, being able to test both galactic and the gravitational models • LOFAR will be competitive with current surveys 26 Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

  27. Thank You Alvise Raccanelli ISW with LOFAR LOFAR Workshop 9/03/2010

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