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Beam profile sensitivity of WMAP CMB power spectrum

Beam profile sensitivity of WMAP CMB power spectrum. Utane Sawangwit & Tom Shanks Durham University. Standard CDM Model - Issues!. Dark matter – exotic particles as yet undetected!  ⇒ 1 in 10 100 fine-tuning coincidence – anthropic?

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Beam profile sensitivity of WMAP CMB power spectrum

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  1. Beam profile sensitivity of WMAP CMB power spectrum UtaneSawangwit & Tom Shanks Durham University

  2. Standard CDM Model - Issues! • Dark matter – exotic particles as yet undetected! •  ⇒ 1 in 10100 fine-tuning coincidence – anthropic? • Even though inflation was set up to get rid of fine-tuning! •  has wrong sign for string theory – Anti-de Sitter v. de Sitter • Standard inflation model⇒10^1077 Universes! • Wrong mass function for galaxies! • Downsizing observed v. bottom-up hierarchy predicted • Feedback - more energy now used in preventing stars form than in forming them under gravity

  3. WMAP 5-Year CMB Map

  4. WMAP 5-Year Power Spectrum Universe comprises: ~72% Dark Energy ~24% CDM ~4% Baryons (Hinshaw et al. 2003, 2006, 2008, Spergel et al. 2003, 2006, 2008)

  5. And yet…….

  6. Sensitivity of WMAP Cl to beam Final Cl result Raw Cl result

  7. WMAP beams (Page et al 2003)

  8. WMAP5 point sources • 390 sources detected (5sigma) in K/Ka/Q/V/W • Complete down to ~1Jy • 373/390 have 5GHz counterparts • Flat spectrum, <α>= -0.09 • We only use compact sources (5 GHz GB6/PMN) Wright et al. (2009)

  9. WMAP5 Radio Source Profiles Radio sources Jupiter beam Gaussian

  10. Comparison with ground-based fluxes

  11. Potential problems with RS beam • Radio Source Clustering? • Estimate based on bright NVSS source clustering... • …suggests clustering is unlikely explanation • But what about the CMB fluctuations – Eddington effect? - referee

  12. New: “CMB-free” point sources CMB-free WMAP5 source detection, Chen & Wright 2009

  13. New: NVSS 1.4GHz point sources

  14. New: Monte Carlo Simulations

  15. Simulations: known source positions

  16. Source detection • Filter the weighted map with • (Wright et al. 2009, Tegmark et al. 1998) W V Q Ka K

  17. Simulations: after source detection

  18. WMAP5 Radio Source Profiles Radio sources Jupiter beam Gaussian

  19. De-beamed power spectra Radio sources Jupiter Gaussian

  20. WMAP peak moved to l=330

  21. A diy beam that works!

  22. Conclusions • CDM assumes “undiscovered physics” + very finely-tuned + problems in many other areas • Model gained overwhelming support from WMAP • But WMAP power spectra highly sensitive to beam • Radio sources indicate wider beams than expected • Systematic errors on WMAP Cl may therefore increase • May reduce constraints on simpler models

  23. Example simpler model: low H0, baryon=1 Shanks (1985) - if Ho<40kms-1Mpc-1 then: • X-ray gas → DM in Coma, Mvir/MX =15h1.5 • Inflationary baryon=1 model in better agreement with nucleosynthesis • Light element abundances baryonh2<0.06 • baryon 1 starts to be allowed for low h • Inflation+EdS => =1 => Globular Cluster Ages of 13-16Gyr require Ho<40kms-1Mpc-1 • But the first acoustic peak is at l=330, not l=220

  24. ‘Do it Yourself’ (DIY) WMAP beam • bS(q) is the beam and bl is the beam transfer function • To get the “true” power spectrum, Cl, divide the raw power spectrum, Cl’, by bl2 • Alternatively to get the beam function bl2, divide raw by true power spectum!

  25. Beam transfer functions • diy beam functions – divide low H0 Cl by raw WMAP Cl & square root • Power-law radio source beam fits give too much power at l>300 • Need spike in bl

  26. Ed Witten -“Strings 2001” String theory prefers a negative  (anti-de Sitter!) rather than the observed positive  http://theory.tifr.res.in/strings/Proceedings/witten/22.html

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