The CMB and Neutrinos

We can all measure the CMB T CMB =2.725 +\- 0.001 K 400 photons/cc at 0.28 ev/cc CMB approx 1% of TV noise!

But no one has measured the neutrino background.

Neutrinos T ν =1.945 K From particle physics: 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 ev<σm ν <2.3 ev (95%cl) From atmospheric neutrinos at SuperK, ν µ ν τ When I say neutrinos. Tritium end point plus mass splittings. (Kraus et al., 2005)

Neutrinos T ν =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 ev<σm ν <1.2 ev (95%cl) From atmospheric neutrinos at SuperK, ν µ ν τ WMAP alone

Neutrinos T ν =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 ev<σm ν <0.58 ev (95%cl) From atmospheric neutrinos at SuperK, ν µ ν τ WMAP+BAO+H 0

Neutrinos T ν =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 ev<σm ν <0.2 ev (95%cl) From atmospheric neutrinos at SuperK, ν µ ν τ Expected from KATRIN (Franenkel, 2011)

Neutrinos T ν =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 ev<σm ν <0.06 ev (~95%cl) From atmospheric neutrinos at SuperK, ν µ ν τ From Planck plus fine scale CMB polarization measurements (ACT, SPT.)

Cosmic Evolution Decoupling surface Us Decoupling at z=1030

Cosmic Evolution

Cosmic Evolution At decoupling

1972

The CMB at decoupling as seen through a Lambda-dominated spacetime (and through our galaxy). WMAP at 61 GHz, 0.5 cm

Angular Power Spectrum 6000 5000 compression WMAP 7yr ACT 148 GHz l(l+1)c l TT /2! [!K 2 ] 4000 3000 2000 Model Acoustic peaks rarefaction compression Silk damping tail 1000 Fundamental mode 0 10 50 100 500 1000 1500 2000 3000 Multipole moment l

WMAP The Atacama researchers to map the CMB by measuring these temperature variations. To search for small distortions that might have been caused by lensing, matter. Bec trinos are ex effect on th venting it fr Cosmology Telescope High definition. The Atacama Cosmology Telescope has enabled astronomers to study the cosmic microwave background (inset) in fine detail, revealing the effects of gravitational lensing. 522 ~10X WMAP resolution 29 APRIL 2011 VOL 332 SCIENCE www.sciencemag.org Published by AAAS

The Millimeter Bolometric Array Camera Window 4 He Fridge 3 He Fridge Pulse Tube 148 GHz 218 GHz Optics Detectors 40K Shield 3K Shield 277 GHz 1 m

Preliminary Power Spectrum Silk damping tail

Number of relativistic species, N eff Dunkley et al., 2011 Silk damping tail The key to limiting N eff is to identify the increased damping at small angular scales in the CMB. Jungman, Kamionkowski, Kosowsky, Spergel 1996 Hou et al., 2011 Bashinsky & Seljak, 2004

N eff WMAP ACT+WMAP 5.3 +/- 1.3 ACT+WMAP+BAO+H 0 4.56 +/- 0.75 SPT+WMAP 3.85 +/- 0.62 SPT+WMAP+BAO+H 0 3.86 +/- 0.42 Komatsu et al., 2011 Dunkley et al., 2011 Keisler et al., 2011

Neutrino Mass #1 Compare today to that at decoupling. Greater relativistic means smaller ρ m /ρ r, enhanced potential evolution, and producing less cosmic structure. e.g., Ichikawa et al., 2005 WMAP+BAO+SN, sum <0.58 (95%cl) WMAP Komatsu et al., 2009

Neutrino Mass #2 Use the cosmic structure between us and the surface of last scattering to lens the CMB, especially the small angles where a massive neutrino inhibits the formation of structure. Lensing is characteristically sensitive to m ν

Lensing remaps & magnifies/de-magnifies cmb patches, smoothing out peaks Lensing smoothes out the peaks and alters the statistics of the CMB Θ(ˆn) = Θ(ˆn + φ) lensed Intervening large-scale potentials deflect CMB photons and distort the CMB. unlensed deflection Lens-speak: Lensing potential: φ Deflection field: d = φ Convergence: κ = 1 2 d The RMS deflection is Simulation from about Das 2.7 arcmins, & Bode but (2008) the deflections are coherent on degree scales. Tuesday, March 15, 2011 Sudeep Das, March 2011 From Sudeep Das 7

Simulations uk 100 deg 2 AAS, Jan 7 2010

We Lensing also detect of lensing CMB detected at 4-sigma at 4σ internally from the CMB 4-point function C φφ l A L C φφ l First internal detection of CMB lensing. Based on Hu & Okamoto estimator plus phase randomization. Detection is from 320 sq. degree of ACT equatorial data only. Shape sensitive to neutrino mass. Das, Sherwin et al. arxiv:1103.2124 Sudeep Das, March 2011 9 Tuesday, March 15, 2011

And from SPT van Engelen et al 2012

closed Geometric Degeneracy CMB alone tells us we are on the geometric degeneracy line open Assume flatness =! b +! c { Ωbh2 WMAP7 only best fit LCDM = 0.0226 +/- 0.00057 Ω c h 2 = 0.1109 +/- 0.0056 h = 0.710 +/- 0.025 σ 8 = 0.801 +/- 0.030 τ = 0.088 +/- 0.015 n s = 0.963 +/- 0.014

The Degeneracy Sherwin et al. 2011

Lensing breaks the geometric degeneracy. Lambda=0 excluded at 3.2 sigma from combination of WMAP and ACT. Sherwin et al. 2011

Neutrino Mass #3 Planck: sensitive to l=2000 in polarization Can look through foregrounds in EE at l>2000. Instruments & measurements underway by ACTPol, Polar, Polarbear, SPTPol. AAS, Jan 7 2010

Gravitational lensing turns E-modes into B-modes. Look for the effects of neutrinos in polarization.

Thank You