Lahav Aarhus nu sep07

Slide1: 

Ofer Lahav University College London Neutrino Masses from LSS Neutrino Masses from the CMB (III) The Dark Energy Survey

Concordance Cosmology: 

Concordance Cosmology SN Ia CMB LSS – Baryonic Oscillations Cluster counts Weak Lensing Integrated Sachs Wolfe Physical effects: * Geometry * Growth of Structure

Massive Neutrinos and Cosmology : 

Massive Neutrinos and Cosmology * Why bother? – absolute mass, effect on other parameters * Brief history of ‘Hot Dark Matter’ * Limits on the total Neutrino mass from cosmology within CDM M < 1 eV * Mixed Dark Matter? * Non-linear power spectrum and biasing – halo model * Combined cosmological observations and laboratory experiments

Brief History of  ‘Hot Dark Matter’: 

Brief History of ‘Hot Dark Matter’ * 1970s : Top-down scenario with massive neutrinos (HDM) – Zeldovich Pancakes * 1980s: HDM - Problems with structure formation * 1990s: Mixed CDM (80%) + HDM (20% ) * 2000s: Baryons (4%) + CDM (26%) +Lambda (70%): But now we know HDM exists! How much?

Globalisation and the New Cosmology : 

Globalisation and the New Cosmology How is the New Cosmology affected by Globalisation? Recall the Cold War era: Hot Dark Matter/top-down (East) vs. Cold Dark Matter/bottom-up (West) Is the agreement on the `concordance model’ a product of Globalisation? OL, astro-ph/0610713

From Great Walls to Neutrino Masses: 

From Great Walls to Neutrino Masses

Slide7: 

Neutrinos decoupled when they were still relativistic, hence they wiped out structure on small scales k > knr = 0.026 (m /1 eV)1/2 m1/2 h/Mpc Colombi, Dodelson, & Widrow 1995 WDM CDM+HDM CDM Massive neutrinos mimic a smaller source term

Neutrino properties: 

Neutrino properties The number of neutrino species Nn affects the expansion rate of the universe, hence BBN. BBN constraints Nn between 1.7 and 3 (95% CL) (e.g. Barger et al. 2003). From CMB+LSS+SN Ia, N =4.2+1.2-1.7 (95% CL) (Hannestad 2005) We shall assume Nn =3 Electron, muon and tau neutrinos Eigen states m1, m2, m3 112 neutrinos per cm3 Wn h2 = Mn/(94 eV)

Neutrino Mass Hierarchy: 

Neutrino Mass Hierarchy

Absolute Masses of Neutrinos: 

Absolute Masses of Neutrinos Based on measured squared mass differences from solar and atmospheric oscillations Assuming m1 < m2 < m3 E & L, NJP 05

What could cosmic probes tell us about Neutrinos and Dark Energy? : 

What could cosmic probes tell us about Neutrinos and Dark Energy?

The Growth factor: degeneracy of Neutrinos Mass and Dark Energy : 

The Growth factor: degeneracy of Neutrinos Mass and Dark Energy Kiakotou, Elgaroy, OL

Slide15: 

Kiakotou, Elgaroy, OL 2007, astro-ph 0709.0253 DP(k)/P(k) = -8 Wn /Wm Not valid on useful scales!

Weighing Neutrinos with 2dFGRS: 

Weighing Neutrinos with 2dFGRS Free streaming effect: Wn/Wm < 0.13 Total n mass M< 1.8 eV 0.001 < Wn < 0.04 (Oscillations) (2dF) a Four-Component Universe ? Elgaroy , Lahav & 2dFGRS team, astro-ph/0204152 , PRL Wn = 0.05 0.01 0.00

What do we mean by ‘systematic uncertainties’?: 

What do we mean by ‘systematic uncertainties’? Cosmological (parameters and priors) Astrophysical (e.g. Galaxy biasing) Instrumental (e.g. ‘seeing’)

Degeneracy of neutrino mass: 

Degeneracy of neutrino mass n= 0.9 n= 1.1 n=1.0 Prior 0< Wm<0.5

Biasing vs. neutrino mass: 

Biasing vs. neutrino mass Elgaroy & Lahav , JCAP, astro-ph/030389 ---- SAM for L>0.75 L* Pg(k) = b2(k) Pm(k) b(k) = a log(k) + c a Total neutrino mass

Weak Lensing is promising: 

Weak Lensing is promising Abazajian & Dodelson (2003) M also Hannestad et al. 2006

Non-linear P(k) with massive neutrinos: 

Non-linear P(k) with massive neutrinos Abazajian et al. (astro-ph/0411552) modeled the effects of neutrino infall into CDM halos and incorporated it in the halo model. The effect is small: P(k)/P(k) » 1% at k » 0.5 h/Mpc for M » 1 eV Future work : high-resolution simulations with CDM, baryons and neutrinos

CMB with massive : 

CMB with massive  E&L 2004 M =0.3, 0.9, 1.5, 6.0 eV Fixed cdm = 0.26

Neutrinos masses and the CMB : 

Neutrinos masses and the CMB If znr > zrec   h2 > 0.017 (i.e. M > 1.6 eV) Then neutrinos behave like matter - this defines a critical value in CMB features * Ichikawa et al. (2004 ) from WMAP1 alone  M < 2.0 eV * Fukugita et al. (2006) from WMAP3 alone  M < 2.0 eV

Normalization vs neutrino mass using WMAP alone + concordance model: 

Normalization vs neutrino mass using WMAP alone + concordance model

Is CMB polarisation useful for neutrino mass?: 

Is CMB polarisation useful for neutrino mass? Fukugita, Ichikawa, Kawasaki, OL, astro-ph/0605362 Not directly, but reduces degeneracy with the reionization optical depth

Ratio of bulk flows with massive neutrinos  =0.04 : 

Ratio of bulk flows with massive neutrinos  =0.04

Deriving Neutrino mass from Cosmology : 

Deriving Neutrino mass from Cosmology All upper limits 95% CL, but different assumed priors !

Forecasting Neutrino mass from Cosmology : 

Forecasting Neutrino mass from Cosmology Note different error definitions and assumed priors !

Combined Cosmology & Terrestrial Experiments : 

Combined Cosmology & Terrestrial Experiments Fogli et al. Hep-ph/0408045

Slide30: 

Combining KATRIN+CMB (Host, OL, Abdalla & Eitel 2007) =>> Ole’s talk

Neutrinos - Summary : 

Neutrinos - Summary * Redshift surveys (+ CMB) Mn < 0.7-1.8 eV Ly- (+ CMB+LSS) Mn < 0.17 eV * Within the L-CDM scenarios, subject to priors. * Alternatives: MDM ruled out. * Future: errors down to 0.05 eV using SDSS+Planck, and weak gravitational lensing of background galaxies and of the CMB. Resolve the neutrino absolute mass!

Baryon Wiggles as Standard Rulers: 

Baryon Wiggles as Standard Rulers

Imaging Surveys : 

Imaging Surveys VST/VISTA DUNE 5000? 2010-2015? moderate 4+5 proposed 20000? (space) 2+1? moderate 2012-2018? proposed Y. Y. Mellier

DUNE: Dark UNiverse Explorer: 

DUNE: Dark UNiverse Explorer Mission baseline: 1.2m telescope FOV 0.5 deg2 PSF FWHM 0.23’’ Pixels 0.11’’ GEO (or HEO) orbit Surveys (3-year initial programme): WL survey: 20,000 deg2 in 1 red broad band, 35 galaxies/amin2 with median z ~ 1, ground based complement for photo-z’s Near-IR survey (J,H). Deeper than possible from ground. Secures z > 1 photo-z’s SNe survey: 2 x 60 deg2, observed for 9 months each every 4 days in 6 bands, 10000 SNe out to z ~ 1.5, ground based spectroscopy

Photometric redshift: 

Photometric redshift Probe strong spectral features (4000 break) Difference in flux through filters as the galaxy is redshifted.

*Training on ~13,000 2SLAQ*Generating with ANNz  Photo-z for ~1,000,000 LRGs MegaZ-LRG: 

*Training on ~13,000 2SLAQ *Generating with ANNz Photo-z for ~1,000,000 LRGs MegaZ-LRG z = 0.046 Collister, Lahav, Blake et al., astro-ph/0607630

Slide37: 

Baryon oscillations Blake, Collister, Bridle & Lahav; astro-ph/0605303

The Dark Energy Survey: 

The Dark Energy Survey Study Dark Energy using 4 complementary techniques: I. Cluster Counts II. Weak Lensing III. Baryon Acoustic Oscillations IV. Supernovae • Two multi-band surveys 5000 deg2 g, r, i, z 40 deg2 repeat (SNe) • Build new 3 deg2 camera and data management system Survey 2010-2015 (525 nights) Response to NOAO AO Blanco 4-meter at CTIO 300,000,000 photometric redshifts

The DES Collaboration: 

The DES Collaboration Fermilab: J. Annis, H. T. Diehl, S. Dodelson, J. Estrada, B. Flaugher, J. Frieman, S. Kent, H. Lin, P. Limon, K. W. Merritt, J. Peoples, V. Scarpine, A. Stebbins, C. Stoughton, D. Tucker, W. Wester University of Illinois at Urbana-Champaign: C. Beldica, R. Brunner, I. Karliner, J. Mohr, R. Plante, P. Ricker, M. Selen, J. Thaler University of Chicago: J. Carlstrom, S. Dodelson, J. Frieman, M. Gladders, W. Hu, S. Kent, R. Kessler, E. Sheldon, R. Wechsler Lawrence Berkeley National Lab: N. Roe, C. Bebek, M. Levi, S. Perlmutter University of Michigan: R. Bernstein, B. Bigelow, M. Campbell, D. Gerdes, A. Evrard, W. Lorenzon, T. McKay, M. Schubnell, G. Tarle, M. Tecchio NOAO/CTIO: T. Abbott, C. Miller, C. Smith, N. Suntzeff, A. Walker CSIC/Institut d'Estudis Espacials de Catalunya (Barcelona): F. Castander, P. Fosalba, E. Gaztañaga, J. Miralda-Escude Institut de Fisica d'Altes Energies (Barcelona): E. Fernández, M. Martínez CIEMAT (Madrid): C. Mana, M. Molla, E. Sanchez, J. Garcia-Bellido University College London: O. Lahav, D. Brooks, P. Doel, M. Barlow, S. Bridle, S. Viti, J. Weller University of Cambridge: G. Efstathiou, R. McMahon, W. Sutherland University of Edinburgh: J. Peacock University of Portsmouth: R. Crittenden, R. Nichol, R. Maartnes, W. Percival University of Sussex: A. Liddle, K. Romer plus postdocs and students

Slide40: 

The Dark Energy Survey UK Consortium (I) PPARC funding: O. Lahav (PI), P. Doel, M. Barlow, S. Bridle, S. Viti, J. Weller (UCL), R. Nichol (Portsmouth), G. Efstathiou, R. McMahon, W. Sutherland (Cambridge) J. Peacock (Edinburgh) Submitted a proposal to PPARC requesting £ 1.7M for the DES optical design. In March 2006, PPARC Council announced that it “will seek participation in DES”. PPARC already approved £220K for current R&D. (II) SRIF3 funding: R. Nichol, R. Crittenden, R. Maartens, W. Percival (ICG Portsmouth) K. Romer, A. Liddle (Sussex) Funding the optical glass blanks for the UCL DES optical work These scientists will work together through the UK DES Consortium. Other DES proposals are under consideration by US and Spanish funding agencies.

DES Forecasts: Power of Multiple Techniques: 

DES Forecasts: Power of Multiple Techniques Assumptions: Clusters: 8=0.75, zmax=1.5, WL mass calibration BAO: lmax=300 WL: lmax=1000 (no bispectrum) Statistical+photo-z systematic errors only Spatial curvature, galaxy bias marginalized, Planck CMB prior Factor 4.6 improvement over Stage II w(z) =w0+wa(1–a) 68% CL DETF Figure of Merit: inverse area of ellipse

DES z=0.8 photo-z shell: 

DES z=0.8 photo-z shell Back of the envelope: improved by sqrt (volume) => Sub-eV from DES (OL, Abdalla, Black; in prep) Mn  0.0 eV 0.4 0.9 1.7

Slide43: 

* 4-5 complementary probes * Survey strategy delivers substantial DE science after 2 years * Relatively modest (~ $20-30M), low-risk, near-term project with high discovery potential * Synergy with SPT and VISTA on the DETF Stage III timescale * Scientific and technical precursor to the more ambitious Stage IV Dark Energy projects to follow: LSST and JDEM DES and a Dark Energy Programme

Some Outstanding Questions:: 

Some Outstanding Questions: * Vacuum energy (cosmological constant, w= -1.000 after all ?) * Dynamical scalar field ? * Modified gravity ? * Why /m = 3 ? * Non-zero Neutrino mass < 1eV ? * The exact value of the spectral index: n < 1 ? * Excess power on large scales ? * Is the curvature zero exactly ?