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Tracking quintessence by cosmic shear constraints from VIRMOS-Descart and CFHTLS and future prospects May 2006 workshop PNC – IPNL Lyon In collaboration with: I.Tereno, J.-P.Uzan, Y.Mellier, (IAP), L.vanWaerbeke (British Columbia U.),... Carlo Schimd DAPNIA / CEA Saclay & IAP Based on: astro-ph/0603158
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Dark energy: parametrization.vs. field theory inspired {baryons, , } + DM + GR {baryons, , } + DM + GR alone cannot account for the cosmological dynamics seen by CMB + LSS + SNe +... GR : not valid anymore? Other “matter” fields? Cosmological constant? Dark energy Dark energy H(z)-H r+m+GR (z) 1/0 approach: 1/0 approach: parameterization of w(z) departures from CDM limitation in redshift ? pivot redshift z p : observable/dataset dependent Not adapted for combining low-z and high-z observables and/or several datasets parameters physics # p.: limitation to likelihood computation perturbations: how ? Fitted T(k) Which class ? Physics-inspired approach: high-energy physics ?! w : full redshift range small # p. perturbations: consistently accounted for Uzan, Aghanim, Mellier (2004); Uzan, astro-ph/0605313
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scalar field quintessence: models CMB SNe, WL, n(z) Inverse power law (Ratra-Peebles): » + SUGRA corr. : 1 p. SUGRA by-product: w(z) and w’(z) at whatever pivot redshift (z p ) z p = 0z p = 0.5 w w’
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quintessence by cosmic shear angular distance angular distance q(z); 3D 2D projection growth factor growth factor amplitude of 3D L/NL power spectrum amplitude + shape of 2D spectra with respect to , quintessence modifies 2pts statistics z=1 10% 20% K = 0 cosmic shear = weak lensing by LSS weak lensing by LSS obs gal statistics, e.g.
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non-linear regime N-body: N-body:... mappings: mappings: stable clustering, halo model, etc.: NL P m (k,z) = f [ L P m (k,z)] normalization to high-z (CMB): ...normalization to high-z (CMB): the modes k enter in non-linear regime ( (k) 1 ) at different time 3D non-linear power spectrum is modified 2D shear power spectrum is modified by k = / S K (z) no more ,but incertitude on TT-CMB Cl’s e.g. Peacock & Dodds (1996) Smith et al. (2003) Ansatz: Ansatz: c, bias, c, etc. not so much dependent on cosmology at every z we can use them, provided we use the correct linear growth factor (defining the onset of the NL regime)... calibrated with CDM N-body sim, 5-10% agreement Huterer & Takada (2005) Q: Q: dependence of 3D NL power spectrum on w Q ? McDonald, Trac, Contaldi (2005)
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pipeline ** Riazuelo & Uzan (2002) C.S., Uzan & Riazuelo (2004) * They include larger framework: scalar-tensor theories of gravitation / extended Q models * CMB can be taken into account at no cost Q models: Q models: inverse power law with/without SUGRA corrections (restricted) parameter space: Q, , n s, z source ; marginalization over z source ** * * *
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dataset CMB: CMB: TT anisotropy spectrum @ WMAP-1yr initial conditions/ SNe: SNe: “goldset” cosmic shear: cosmic shear: VIRMOS-Descart + CFHTLS deep VanWaerbeke, Mellier, Hoekstra (2004) Semboloni et al. (2005) + CFHTLS wide/22deg2 & 170deg2 (synth) 0.92, 1.0, 0.76 n gal 15, 22, 20 /arcmin 2 area 8.5, 2.2, 22(170) deg 2 I AB 24.5, 26, 26 wl observables: wl observables: top-hat variance; aperture mass variance Riess et al. (2004) cosmic shear: cosmic shear: by wide-field imager/DUNE-like satellite mission Hoekstra et al. (2005) normalization
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cosmic shear data*: effects of L-NL mapping Ratra-Peebles SUGRA * Joint VIRMOS-Descart + CFHTLS deep + CFHTLS wide/22deg2 analysis Peacock & Dodds (1996) Smith et al. (2003) Top-hat shear variance Peacock & Dodds Smith et al.
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wide survey : Q - geometrical effects (RP) Ratra-Peebles Peacock & Dodds (1996) real data CFHTLS wide/22deg2 (real data) synth CFHTLS wide/170deg2 (synth) top-hat top-hat variance aperture mass variance > 20 arcmin only scales > 20 arcmin synth CFHTLS wide/170deg2 (synth) top-hat top-hat variance
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wide survey : Q - geometrical effects (SUGRA) SUGRA Peacock & Dodds (1996) real data CFHTLS wide/22deg2 (real data) synth CFHTLS wide/170deg2 (synth) top-hat top-hat variance aperture mass variance > 20 arcmin only scales > 20 arcmin synth CFHTLS wide/170deg2 (synth) top-hat top-hat variance
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cosmic shear alone : summary Two classes of cosmological parameters: other parameters: other parameters: sensible to L-NL mapping Q parameters: Q parameters: not sensible to linear-to-nonlinear mapping This conclusions holds for both Ratra-Peebles and SUGRA models real data (VIRMOS-Descart + CFHTLS deep + CFHTLS wide/22deg2) synthetic data (CFHTLS wide/170deg2) Confirmation of results based on real data joint analysis Based on top-hat shear variance measurements Agreement top-hat shear variance – aperture mass variance Compatible with CDM ( =0), towards n s =0.95 (like WMAP3!) Analysis of wide scale reducing the non-linear contamination confirming Simpson & Bridle (2005)
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cosmic shear + SNe + CMB: Q equation of state Ratra-PeeblesSUGRA (n s,z s ): marginalized ; all other parameters: fixed SNe: confirmed literature TT-CMB: rejection from first peak (analytical (Doran et al. 2000) & numerical) Mass scale M: indicative Cosmic shear Cosmic shear (real data only): RP: RP: strong degeneracy with SNe SUGRA: SUGRA: 1) beware of systematics! (wl: calibration when combining datasets) 2) limit case: prefectly known/excluded Q model (weakly -dependece) Van Waerbeke et al. (2006)
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cosmic shear & CMB: variance on 8h -1 Mpc ( 8 ) contours follow 8 degeneracy WMAP3 – weak lensing: WMAP3 – weak lensing: stress {h, reion,normalization, q } Ratra-Peebles SUGRA Spergel et al. 2006 Check normalization procedure Check calibration of datasets Deviations from CDM ?
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a remark on constant w z de z acc de / m = 0.6/0.4 Spergel et al. 2006 Hoekstra et al. 2006 Astier et al. 2005 w = const
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Q by cosmic shear: Fisher matrix analysis CFHTLSwide/170 SNAP Like previous data analysis: Like previous data analysis: all but ( , q,n s ) fixed, z s marginalized SNAP DUNE CFHTLSwide/170 Adding a parameter: Adding a parameter: Like upper plots but reion marginalized size, orientation
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conclusions & prospects quintessence at low-z quintessence at low-z by SNe + cosmic shear, using high-z informations (TT-CMB/Cl normalization) CDM dynamical models of DE (not parameterization): CDM wide field surveys wide field surveys are needed DUNE, LSST data for the first time cosmic shear data to this task improvement: improvement: bigger parameter space 1. 1. combining also CMB data (high-z effects of DE) +... ; 2. 2. MCMC analysis; 3. 3. deviation from GR, e.g. EQ w Q < -1 NL regime:caveat NL regime: L-NL mappings (caveat) Martin, C.S., Uzan (2005) some parameters (n S ) are sensible to L-NL mappings ( integrated effect ?), Q parameters feel only geometry Tereno et al. (2005) deep surveys deep surveys help to exploit the linear regime SKA Schneider (1999); Chang, Réfrégier, Helfand (2004) consistent joint analysis of high-z (CMB) and low-z (cosmic shear, Sne,...) observables no stress between datasets; no pivot redshift analysisseveralparameters analysis of realistic (=dynamical) models of DE using several parameters other techniques other techniques: cross-correlations (ISW), 3pts functions, tomography Work in progress: pipeline: pipeline: Boltzmann code + lensing code + data analysis by grid method: in collaboration with: I.Tereno, Y.Mellier, J.-P. Uzan, R. Lehoucq, A. Réfrégier & DUNE team
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Thank you
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Q by cosmic shear: Fisher matrix analysis All but ( , q ) parameters: fixed SNe “goldset” CFHTLS wide: TT @ CMB WMAP 1yr A = 170 deg 2 Ratra-PeeblesSUGRA n gal = 20/arcmin 2 DUNE-like: A= 20000 deg 2 n gal = 35/arcmin 2
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