1. The CMB and Neutrinos

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

3. But no one has measured the neutrino background.

4. Neutrinos T =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family When I say “neutrinos”…. 0.05 eV <  m < 2.3 eV (95%cl) From atmospheric neutrinos at SuperK,      Tritium end point plus mass splittings. (Kraus et al., 2005) From particle physics:

5. Neutrinos T =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 eV <  m < 1.2 eV (95%cl) WMAP alone From atmospheric neutrinos at SuperK,     

6. Neutrinos T =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 eV <  m < 0.58 eV (95%cl) From atmospheric neutrinos at SuperK,      WMAP+BAO+H 0

7. Neutrinos T =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 eV <  m < 0.2 eV (95%cl) From atmospheric neutrinos at SuperK,      Expected from KATRIN (Franenkel, 2011)

8. Neutrinos T =1.945 K 3 known families, ~equal numbers of neutrinos and antineutrinos. 113 neutrinos/cc/family 0.05 eV <  m < 0.06 eV (~95%cl) From atmospheric neutrinos at SuperK,      From Planck plus fine scale CMB polarization measurements (ACT, SPT….)

9. Cosmic Evolution Us Decoupling at z=1030 Decoupling surface

10. Cosmic Evolution

12. At decoupling

13. 1972

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

15. Angular Power Fundamental mode rarefaction compression “Acoustic peaks” Model compression Spectrum Silk damping tail

16. The Atacama Cosmology Telescope ~10X WMAP resolution WMAP

17. 148 GHz 218 GHz 277 GHz Pulse Tube 4 He Fridge 3 He Fridge 40K Shield 3K Shield Window 1 m Detectors Optics The Millimeter Bolometric Array Camera

18. Preliminary Power Spectrum Silk damping tail

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

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

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

22. 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

23. From Sudeep Das Lensing smoothes out the peaks and alters the statistics of the CMB

24. Simulations AAS, Jan 7 2010 100 deg 2 uK

25. AAS, Jan 7 2010 Simulations 100 deg 2 uK

26. Lensing of CMB detected at 4  Based on Hu & Okamoto estimator plus phase randomization. Shape sensitive to neutrino mass.

27. And from SPT van Engelen et al 2012

29. “Geometric Degeneracy” CMB alone tells us we are on the “geometric degeneracy” line closed open Assume flatness WMAP7 only best fit LCDM {  b h 2 = 0.0226 +/- 0.00057  c h 2 = 0.1109 +/- 0.0056 h = 0.710 +/- 0.025  8 = 0.801 +/- 0.030  = 0.088 +/- 0.015  n s = 0.963 +/- 0.014

30. The Degeneracy Sherwin et al. 2011

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

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

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

34. Thank You