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 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 10^10⇒ 77 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

WMAP 5-Year CMB Map

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)

And yet…….

Sensitivity of WMAP Cl to beam

Raw Cl result

Final Cl result

WMAP beams (Page et al 2003)

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)

WMAP5 Radio Source Profiles

Gaussian

Jupiterbeam

Radio sources

Comparison with ground-based fluxes

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

New: “CMB-free” point sources

CMB-free WMAP5 source detection, Chen & Wright 2009

New: NVSS 1.4GHz point sources

New: Monte Carlo Simulations

Simulations: known source positions

Source detection

Filter the weighted map with

(Wright et al. 2009, Tegmark et al. 1998)

W

V

Q

Ka

K

Simulations: after source detection

WMAP5 Radio Source Profiles

Gaussian

Jupiterbeam

Radio sources

De-beamed power spectra

Gaussian

Radio sources

Jupiter

WMAP peak moved to l=330

A diy beam that works!

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

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

‘Do it Yourself’ (DIY) WMAP beam

bS() is the beam and bl is the beam transfer function

To get the “true” power spectrum, Cl, divide the raw power spectrum, Cl’, by bl

2

Alternatively to get the beam function bl

2, divide raw by true power spectum!

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

Ed Witten -“Strings

2001”

http://theory.tifr.res.in/strings/Proceedings/witten/22.html

String theory prefers a negative (anti-de Sitter!) rather than the observed positive