Cosmological neutrino masses (including steriles) Viviana Niro ITP, - - PowerPoint PPT Presentation

Cosmological neutrino masses (including steriles)

Viviana Niro

ITP, Heidelberg

CERN, 30 March, 2017

Neutrinos: the quest for a new physics scale

TR 33 The Dark Universe B

• n

n Munich Heidelberg

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 1 / 17

The standard model of cosmology

ΛCDM: Standard Model of Cosmology Hubble parameter H0 Baryon density in the Universe ωb ≡ Ωbh2 Cold Dark Matter density in the Universe ωcdm ≡ Ωcdmh2 Optical depth at reionization τreio Amplitude of scalar power spectrum of primordial fluctua- tions at the pivot scale k∗ = 0.05 Mpc−1 AS Scalar spectral index of primordial density fluctuations ns Sum of of the three active neutrino masses mν ≡ Mν τreio: CMB photons scattering off electrons, after reionization produced by stars, quasars Planck data in remarkable agreement with ΛCDM model

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 2 / 17

Neutrino mass in cosmology

Cosmology provides important information on the sum of neutrino masses Mν → affects the expansion rate of the Universe and the way large-scale structures form and evolve Cosmic Microwave Background (CMB) anisotropies → Early Integrated Sachs Wolfe Effect ISW: change in the temperature of CMB photons due to changing of gravitational potential wells (expansion of the Universe) eISW: when neutrinos become non-relativistic, they influence the time variation of the gravitational potential Gravitational lensing measurements → increasing the neutrino mass suppresses the lensing potential (neutrino masses reduce the amplitude of matter fluctuations on small scales)

• J. Lesgourgues, L. Perotto, S. Pastor, M. Piat, arXiv:astro-ph/0511735

see talk by J. Lesgourgues and references therein

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 3 / 17

Planck results on neutrino mass (LCDM)

Planck TT+lowP (coloured points): Mν < 0.72 eV; Planck collaboration, arXiv:1502.01589 Planck TT+lowP+lensing (solid black contours): Mν < 0.68 eV; Planck TT+lowP+lensing+BAO (filled contours): Mν < 0.25 eV;

0.0 0.4 0.8 1.2 1.6

Σmν [eV]

55 60 65 70 75

H0 [km s−1 Mpc−1]

0.60 0.64 0.68 0.72 0.76 0.80 0.84

σ8

Mν <0.49 eV (TT+TE+EE+lowP) Mν <0.17 eV (TT+TE+EE+lowP+BAO) Mν <0.59 eV (TT+TE+EE+lowP+lensing) Mν <0.22 eV (TT+TE+EE+lowP+BAO+lensing)

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 4 / 17

Effect of τreio prior and extended cosmology

τ = 0.055 ± 0.009 (low-multipole EE data from HFI), Σmν < 0.14 eV (Planck TT,TE,EE+SimLow+Lensing+BAO)

Planck collaboration, arXiv: 1605.02985

58 63 69

H0

0.58 1.2

Mν

0.64 0.75 0.85

σ8

0.04 0.088 0.14

τreio

CMB CMB+τ

A.Cuesta, Proceedings SEA 2016

Extensions of LCDM model: different parameters can be added to the analysis Example (Planck TT+lowP+lensing+BAO): NeffCDM: Mν < 0.32 eV 95% C.L., ωCDM: Mν < 0.37 eV at 95% C.L.

Planck collaboration, arXiv:1502.01589

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 5 / 17

Galaxy surveys

Massive neutrinos lead to a suppression on the matter power spectrum at small scales (neutrinos do not cluster gravitationally on small scales) ⇒ measurements of the full shape of the matter power spectrum are of great importance for neutrino physics: they are able to put tight constraints on the sum of neutrino masses

• W. Hu, D. J. Eisenstein, M. Tegmark, astro-ph/9712057; J. Lesgourgues, S. Pastor, astro-ph/0603494

0.02 0.05 0.10 0.20

k (h Mpc−1)

0.80 0.85 0.90 0.95 1.00 1.05 1.10

P(k)/P(k)Mν = 0

Mν = 0. 00eV Mν = 0. 15eV Mν = 0. 30eV

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 6 / 17

Luminous red galaxies vs emission line galaxies

Galaxy bias b2: depends on the type of galaxies; marginalised in the analysis

0.2 0.4 0.6 0.79 Mν[eV] CMB15+LRG +lensing CMB15+LRG+BAO +lensing 0.19 0.39 0.58 0.78 Mν[eV] CMB15+WZ +lensing CMB15+WZ+BAO +lensing

LRG galaxies WZ galaxies CMB15 + SDSS-DR7 LRG + BAO: 0.13 eV, CMB15 + WZ + BAO: 0.14 eV

A.J. Cuesta, VN, L. Verde, arXiv:1511.05983 [astro-ph.CO]

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 7 / 17

Lyman-α data

To date the strongest constraint on Mν is provided by the joint analysis of CMB15, BAO and Lyman-α forest data: Palanque-Delabrouille et al., arXiv:1506.05976 [astro-ph.CO] Mν < 0.12 eV (95% C.L.) From CMB13 results: Palanque-Delabrouille et al., arXiv:1410.7244 [astro-ph.CO] Mν < 0.15 eV (including BAO : 0.14 eV) (95% C.L.) Lyman-α: estimate the matter power spectra from absorption observed in quasar spectra Hydrodynamic simulations to relate neutral hydrogen in the inter-galactic medium with the underlying mass distribution

Palanque-Delabrouille et al., arXiv:1506.05976 [astro-ph.CO]

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 8 / 17

BAO and τreio measurements

DR12 CMASS P(k) versus BAO datasets: CMB temperature anisotropies, BAO data, up-to-date constraint on τreio: Mν < 0.151 eV 95% C.L. With the addition of Planck high-l polarization data: Mν < 0.118 eV 95% C.L.

• S. Vagnozzi, E. Giusarma, O. Mena, et al., arXiv:1701.08172 [astro-ph.CO]
• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 9 / 17

Neutrino hierarchy

the neutrino mass hierarchy, normal or inverted, as well as the sum of the three active neutrino masses, are quantities that are still unknown For a zero lightest neutrino mass (m0 = 0), the predictions for the sum Mν is: Mν = 58.5 ± 0.48 meV (NO); Mν = 98.6 ± 0.85 meV (IO) with (1σ uncertainties) S. Hannestadad and T. Schwetz, arXiv:1606.04691 [astro-ph.CO] ∆m2

21 = 7.49+0.19 −0.17 × 10−5eV2;

∆m2

31 = 2.484+0.045 −0.048 × 10−3eV2(NO);

∆m2

32 = −2.467+0.041 −0.042 × 10−3eV2(IO)

• M. C. Gonzalez-Garcia, M. Maltoni, and T. Schwetz, arXiv:1409.5439;

see talk M. C. Gonzalez-Garcia and references therein

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 10 / 17

Neutrino mass ordering and cosmological bounds

Posterior odds of IO versus NO pI/pN S. Hannestadad and T. Schwetz, arXiv:1606.04691 [astro-ph.CO] pO = π(O) ∞ dm0L(D|m0, O) π(N) ∞ dm0L(D|m0, N) + π(I) ∞ dm0L(D|m0, I) π(I) = 0.55; π(N) = 0.45 ⇒ posterior odds of 1.55:1 for NO vs IO. Posterior likelihood function from Planck+BAO+H0

See also discussion in F. Simpson, R. Jimenez,

• C. Pena-Garay, L. Verde, arXiv:1703.03425 [astro-ph.CO]; T. Schwetz, K. Freese, M. Gerbino et al, arXiv:1703.04585

[astro-ph.CO]; F. Capozzi, E. Di Valentino, E. Lisi, A. Marrone, A. Melchiorri, A. Palazzo, arXiv:1703.04471 [hep-ph]

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 11 / 17

Future surveys

expect a sensitivity σ(Mν) close to 0.02 eV (1-sigma) around the year 2025 for a survey like Euclid combined with Planck (planned launch date for Euclid 2020)

• B. Audren, J. Lesgourgues, S. Bird, M. G. Haehnelt and M. Viel, arXiv:1210.2194

CMB satellite of next generation like Core+ combined with Euclid could further improve the sensitivity Other surveys, like DESI, can reach similar sensitivity on Mν. DES can reach a sensitivity σ(Mν) close to 0.06 eV

• A. Font-Ribera, et al., arXiv:1308.4164 [astro-ph.CO]
• O. Lahav, et al., arXiv:0910.4714 [astro-ph.CO]

Good prospects to detect the absolute neutrino mass scale with cosmology

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 12 / 17

Prospects for Euclid

• S. Hannestadad and T. Schwetz, arXiv:1606.04691 [astro-ph.CO]

Posterior likelihood function from simulated future data (EUCLID+Planck CMB), one massive neutrino with mν = 0.06 eV and 2.046 massless neutrinos; gray shaded region:

• ne-sided upper bound on Mν at 95% C.L.

Right panel: posterior likelihood as a function of m0 for NO and IO

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 13 / 17

Degeneracy between H0 and mν

Correlation between Mν, h, ωcdm with BAO, along different angles than with CMB data BAO-DESI experiment → ratio rs(zdrag)/DV (zBAO) CMB → lensing and angular diameter distance ∆ωcdm ≃ −0.5∆ων, ∆h ≃ −0.017(∆Mν/1eV ) ≃ −1.6∆ων ∆ωcdm ≃ ∆ων, ∆h ≃ −0.13(∆Mν/1eV ) ≃ −12∆ων

• M. Archidiacono, T. Brinckmann, J. Lesgourgues, V. Poulin, arXiv:1610.09852 [astro-ph.CO]
• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 14 / 17

Sterile neutrinos

Planck TT+lowP+lensing+BAO: meff = (∆Neff )3/4 mTH

s

, meff = (∆Neff ) mDW

s

Neff < 3.7; meff

ν;sterile < 0.38 eV at 95% C.L. Planck collaboration, arXiv:1502.01589 See talk by C. Giunti on neutrino anomalies and talk by N. Saviano on secret neutrino interactions, and references therein

Already using Planck2013+SBL: ∆Neff ≥ 0.86 strongly disfavoured, evidence against the 3+1 model compared to the model with only the 3 active neutrinos

• J. Bergstrom, M. C. Gonzalez-Garcia, VN, J. Salvado, arXiv:1407.3806 [hep-ph]
• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 15 / 17

νµ disappearance results and cosmology

Exclusion regions at 95% CL from Planck, MINOS, IceCube, and the SBN forecast Dashed line: Planck constraint with m4 calculated using the DW mechanism Dot-dash line: Planck constraint using a large lepton-asymmetry, L = 10−2

• S. Bridle, J. Elvin-Poole, J. Evans, S. Fernandez, P. Guzowski, S. Soldner-Rembold, 1607.00032 [astro-ph.CO]
• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 16 / 17

Conclusions

Cosmology has a Standard Model (LCDM) and can constrain the sum of neutrino masses Mν The tightest bound is Mν < 0.12 eV at 95% C.L. So far no detection, but upcoming data could be used to determine the neutrino mass Mν We are in the era of precision cosmology: ⇒ interesting results to come and nice interplay between cosmology and particle physics

• V. Niro (ITP, Heidelberg)

ν mass in cosmology CERN 17 / 17