The Cosmic Microwave Background as a Probe of the Early Universe and Novel Physics David Spergel Philadelphia March 16, 2012 Friday, March 16, 2012
Overview What can we measure? Past Present Future Friday, March 16, 2012
Measuring the Initial Conditions: Simple Version Friday, March 16, 2012
Complexities Friday, March 16, 2012
What do we want to measure? Initial conditions produced during the first moments of the universe Scalar, (Vector), and Tensor fluctuations Power spectrum Non-Gaussian features (bispectrum to bubble collisions) Friday, March 16, 2012
WMAP Spacecraft upper omni antenna back to back line of sight Gregorian optics, 1.4 x 1.6 m primaries 60K passive thermal radiator focal plane assembly feed horns secondary reflectors 90K thermally isolated instrument cylinder 300K warm spacecraft with: medium gain antennae - instrument electronics - attitude control/propulsion - command/data handling deployed solar array w/ web shielding - battery and power control MAP990422 Friday, March 16, 2012
W - 94GHz Friday, March 16, 2012
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FOREGROUND CORRECTED MAP Friday, March 16, 2012
FOREGROUND CORRECTED MAP Friday, March 16, 2012
FOREGROUND CORRECTED MAP Friday, March 16, 2012
What Have We Learned? Simple model fits a wide range of data (only 5 numbers) Age of universe:13.7 Gyr Composition: Atoms: 4% Matter: 23% Dark Energy: 73% Scale Invariant Fluctuations seed growth of galaxies With WMAP7, we have narrowed the First Stars formed ~200 constraints on the six-dimensional parameter Myr after the big bang space by 30,000 from pre-WMAP CMB Friday, March 16, 2012
Today’ s Universe (Sloan Digital Sky Survey) Friday, March 16, 2012
THlozek et all. 2011 Friday, March 16, 2012
All of the pieces seem to fit…. Supernova distances Gravitational Lenses Hubble Constant Nuclear Abundances Age of Universe Lyman alpha forest Cluster Properties Galaxy Velocities Friday, March 16, 2012
The Universe is Simple? Fluctuations are accurately as Gaussian, Random Phase No evidence for spatial variations in fluctuation properties No evidence for interaction terms No sign of global topology Friday, March 16, 2012
ACT Led by Lyman Page. Devlin (Penn) leads much of the instrumental effort. 80 scientists on 5 continents 6-meter telescope on Cerro Tocco (5190 m) in the Atacama Desert. Observing the sky at 148, 218 and 277 Ghz Friday, March 16, 2012
ACT and SPT probe smaller scales /SPT Sudeep Das for the ACT collaboration Friday, March 16, 2012
Friday, March 16, 2012
Improving Detectors ACT: Observed 2008-2010; Analysis Underway ACTPOL: First light in May 2012. Survey starts in July 2012. Wide (6000 sq deg) + Deep (150 sq deg) surveys Advanced ACTPOL: Proposed next generation detectors Friday, March 16, 2012
ACT 148 GHz map Data released on lambda.gsfc.nasa.gov soon 5 degrees Radio Source Incomplete Sky Cluster Coverage 3% of data Friday, March 16, 2012
NGC 1055 Friday, March 16, 2012
IRAS ACT 220 GHz Friday, March 16, 2012
ACT Sky Coverage 2009+2010 2008 ACT Stripe from Marriage et al. (2011 ) Friday, March 16, 2012
ACT Sky Coverage 2009+2010 El Gordo 2008 ACT Stripe from Marriage et al. (2011 ) Friday, March 16, 2012
Seven or more acoustic peaks Dunkley et al. 2011 Friday, March 16, 2012
Early universe physics ⎡ 4 /3 ⎤ Dunkley et al. 2011 ⎛ ⎜ ⎞ ρ rel = 7 4 N eff ρ γ ⎢ ⎥ ⎟ 8 ⎝ 11 ⎠ ⎣ ⎦ Neutrinos: More species, longer radiation domination, changes equality redshift, suppress early acoustic oscillations and adds phase shift. SPT+WMAP: N=3.86 ± 0.42 Helium: Usually assume Y P =0.24, predicted by BBN � More helium decreases electron density, increasing damping. Y p = 0.30 ± 0.03 (SPT+WMAP). Friday, March 16, 2012
Clusters as Cosmological Probes SZ signal measures integrated pressure in cluster SZ signal is redshift- independent, so an SZ- selected cluster sample should be a mass-selected sample. Potentially, number counts could be an important dark energy probe. Key step: lensing calibration Subaru Image: Takada, Miyatake, et al. Friday, March 16, 2012
Clusters Measurements of N(M,z) have the potential to probe the growth rate of structure and detect non-Gaussianiaties Challenge is to convert observable to mass and be sure that it doesn’ t evolve with redshift. Eddington bias: most massive clusters are likely lower mass objects with large observational scatter. (Need to know the error distribution in the 2-sigma tail) Friday, March 16, 2012
“El Gordo” Detected ¡in ¡2008 ¡ACT ¡maps ¡of ¡ Chandra X-ray Observations Southern ¡Strip ¡(Menanteau ¡et ¡al. ¡2010, ¡ o ACIS-I, 60 ks Marriage ¡et ¡al. ¡2011) o Spitzer IRAC warm-phase o Strongest ¡SZ ¡decrement ¡over ¡755 ¡ follow-up deg 2 ¡ (South ¡+ ¡Equator) ¡ o Imaged ¡at ¡3.6 ¡ µ m ¡and ¡4.5 ¡ µ m OpIcal ¡follow-‑up: ¡ 89 redshifts! o Imaged ¡( griz ) ¡at ¡SOAR/SOI ¡ o VLT/FORS2 Friday, March 16, 2012
A Remarkable Bullet-like Cluster at z~0.87 “El Gordo” Menanteau et al. (2011, arXiv:1109.0953) Friday, March 16, 2012
A Remarkable Bullet-like Cluster at z~0.87 “El Gordo” Menanteau et al. (2011, arXiv:1109.0953) Friday, March 16, 2012
A Remarkable Bullet-like Cluster at z~0.87 “El Gordo” Menanteau et al. (2011, arXiv:1109.0953) Friday, March 16, 2012
A Remarkable Bullet-like Cluster at z~0.87 “El Gordo” Menanteau et al. (2011, arXiv:1109.0953) Friday, March 16, 2012
A Remarkable Bullet-like Cluster at z~0.87 “El Gordo” Menanteau et al. (2011, arXiv:1109.0953) Friday, March 16, 2012
“El Gordo” is Hot and Luminous!! Core-excised Integrated spectrum kT = 14 . 5 ± 0 . 1 keV L X = 2 . 19 × 10 45 erg s − 1 L bol = 1 . 36 × 10 46 erg s − 1 Compared with Markevitch et al. (1998) Friday, March 16, 2012
“El Gordo,” Chandra Imaging Friday, March 16, 2012
“El Gordo,” Chandra Imaging Wake! Cometary shape (even 2 tails!) 20-40% surface brightness suppression ≈ 35”x60” Friday, March 16, 2012
“El Gordo,” Chandra Imaging Wake! Cometary shape (even 2 tails!) 20-40% surface brightness suppression ≈ 35”x60” Low entropy, bright, offset peak Friday, March 16, 2012
“El Gordo,” Chandra Imaging Wake! Cometary shape (even 2 tails!) 20-40% surface brightness suppression ≈ 35”x60” Low entropy, bright, offset peak Steep brightness gradient β model profile Friday, March 16, 2012
Rarity of ACT-CL J0102-4915 - Based on its exceptional mass • Combined Mass from optical Unlikely Falsify Λ CDM +X-ray+SZ: All Sky L M 200 = (2 . 16 ± 0 . 32) × 10 15 h − 1 i k 70 M ⊙ e l y • Area of survey: ACT: 755 deg 2 ACT+SPT: 2800 deg 2 • Mortonson et al. (2011) exclusion curves for Λ CDM and quintenssence parameter distribution. • Cluster is unlikely in the ACT survey area alone (3 σ ), but is not a highly unlikely occurrence in the ACT+SPT sky region if its mass is 1- σ or more below the nominal mass. No tension with Λ CDM, since the cluster is not unexpected in the entire sky. Friday, March 16, 2012
Gravitational Lensing of the CMB Intervening large-scale potentials deflect CMB photons and distorts the CMB. The rms deflection is about 2.7 arcmins, but the deflections are coherent on degree scales. Friday, March 16, 2012
ACT Lensing Detection Lensing deflects photons and produce non-Gaussian signal: Non-trivial 4-pt function Lensing power spectrum is a meausure of the amplitude of fluctuations along the line of sign Das et al. arXiv 1103.0419 Friday, March 16, 2012
Direct Detection of Dark Energy from the CMB Friday, March 16, 2012
This is just the beginning of CMB Lensing Studies Planck ACTPOL Friday, March 16, 2012
E + B modes Scalar fluctuations generate E-modes. They produce TT, TE and EE correlations Tensor fluctuations generate equal amounts of E and B modes. They produce TT, EE and BB correlations Gravitational lensing rotate polarization and converts E modes into B modes. Figure from Dodelson et al. NAS White Paper astro-ph/0902.3796 Friday, March 16, 2012
Next Step: ACTPOL Funded by NSF for 2011-2016 Camera now under construction... 25 times faster survey speed and polarization sensitivity First light in 2012 Wide survey (~4000 sq. degrees) Deep survey (5 x 25 sq degree fields) Friday, March 16, 2012
Why Measure High l Polarization? More modes/more sky coverage leads to more accurate parameters. New discovery space (another e-fold of inflation) Sensitive to ionization history New Lens sheet: BB power spectrum (directly related to the convergence power spectrum) has a signal/noise of 3000 in an all-sky 0.1 uK 2 Friday, March 16, 2012
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The New Frontier Full sky polarization survey to l = 5000 would have 6 times the number of modes as Planck Friday, March 16, 2012
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