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Tracking quintessence by cosmic shear

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Title: Tracking quintessence by cosmic shear


1
Tracking quintessence by cosmic
shear constraints from VIRMOS-Descart and CFHTLS
and future prospects
Carlo Schimd DAPNIA / CEA Saclay IAP
I.Tereno, J.-P.Uzan, Y.Mellier, (IAP),
L.vanWaerbeke (British Columbia U.), ...
In collaboration with
astro-ph/0603158
Based on
May 2006
workshop PNC IPNL Lyon
2
Dark energy parametrization .vs. field theory
inspired
?
baryons,g,n DM GR alone cannot account for
the cosmological dynamics seen by CMB LSS SNe
...
Dark energy ? H(z)-HrmGR(z)
?
Other matter fields? Cosmological constant?
?
GR not valid anymore?
Uzan, Aghanim, Mellier (2004) Uzan,
astro-ph/0605313
3
scalar field quintessence models
?
Inverse power law (Ratra-Peebles)
? 1 p. ( a )
?
SUGRA corr.
SNe, WL, n(z)
CMB
?
by-product w(z) and w(z) at whatever pivot
redshift (zp)
zp 0
zp 0.5
SUGRA
w
w
4
quintessence by cosmic shear
gal
cosmic shear weak lensing by LSS
g
obs
? statistics, e.g.
2pts statistics
with respect to L , quintessence modifies
  • angular distance ? q(z) 3D?2D projection
  • growth factor ? amplitude of 3D L/NL power
    spectrum
  • ? amplitude shape of 2D spectra

20
10
z1
K 0
5
non-linear regime
  • N-body ...
  • mappings stable clustering, halo model, etc.

e.g. Peacock Dodds (1996) Smith et al.
(2003)
NLPm(k,z) fLPm(k,z)
calibrated with LCDM N-body sim, 5-10 agreement
Huterer Takada (2005)
Q dependence of 3D NL power spectrum on wQ ?
?
McDonald, Trac, Contaldi (2005)
  • Ansatz dc, 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)...
  • ...normalization to high-z (CMB)

the modes k enter in non-linear regime ( s(k)?1 )
at different time ? 3D non-linear power spectrum
is modified ? 2D shear power spectrum is modified
by k / SK (z) no more s8,but incertitude on
TT-CMB Cls
?
?
6
pipeline



C.S., Uzan Riazuelo (2004)



Riazuelo Uzan (2002)
  • Q models inverse power law with/without SUGRA
    corrections
  • (restricted) parameter space

WQ, a, ns, zsource marginalization over
zsource

They include larger framework scalar-tensor
theories of gravitation / extended Q models

CMB can be taken into account at no cost
7
dataset
  • CMB TT anisotropy spectrum _at_ WMAP-1yr ?
    initial conditions/

normalization
  • SNe goldset

Riess et al. (2004)
VanWaerbeke, Mellier, Hoekstra (2004)
  • cosmic shear VIRMOS-Descart
  • CFHTLS deep

Semboloni et al. (2005)
CFHTLS wide/22deg2 170deg2 (synth)
Hoekstra et al. (2005)
ltzgt ? 0.92, 1.0, 0.76 ngal ? 15, 22, 20
/arcmin2 area ? 8.5, 2.2, 22(170) deg2 IAB ?
24.5, 26, 26
?
wl observables top-hat variance aperture mass
variance
?
cosmic shear by wide-field imager/DUNE-like
satellite mission
8
cosmic shear data effects of L-NL mapping
Top-hat shear variance
Peacock Dodds (1996)
?
Ratra-Peebles
Smith et al. (2003)
?
Peacock Dodds
?
SUGRA
Smith et al.
?

Joint VIRMOS-Descart CFHTLS deep CFHTLS
wide/22deg2 analysis
9
wide survey Q - geometrical effects (RP)
Peacock Dodds (1996)
CFHTLS wide/22deg2 (real data)
?
top-hat variance
CFHTLS wide/170deg2 (synth)
?
top-hat variance
Ratra-Peebles
?
CFHTLS wide/170deg2 (synth)
aperture mass variance
CFHTLS wide/170deg2 (synth)
?
top-hat variance
?
only scales gt 20 arcmin
10
wide survey Q - geometrical effects (SUGRA)
Peacock Dodds (1996)
CFHTLS wide/22deg2 (real data)
?
top-hat variance
CFHTLS wide/170deg2 (synth)
?
top-hat variance
SUGRA
?
CFHTLS wide/170deg2 (synth)
aperture mass variance
CFHTLS wide/170deg2 (synth)
?
top-hat variance
?
only scales gt 20 arcmin
11
cosmic shear alone summary
?
real data (VIRMOS-Descart CFHTLS deep CFHTLS
wide/22deg2)
?
Two classes of cosmological parameters
Q parameters not sensible to linear-to-nonlinear
mapping
?
confirming Simpson Bridle (2005)
other parameters sensible to L-NL mapping
?
?
This conclusions holds for both Ratra-Peebles and
SUGRA models
?
Based on top-hat shear variance measurements
?
synthetic data (CFHTLS wide/170deg2)
?
Confirmation of results based on real data joint
analysis
?
Agreement top-hat shear variance aperture mass
variance
?
Analysis of wide scale ? reducing the non-linear
contamination ?
?
Compatible with LCDM (a0), towards ns0.95 (like
WMAP3!)
12
cosmic shear SNe CMB Q equation of state
Ratra-Peebles
SUGRA
(ns,zs) marginalized all other parameters
fixed
?
Mass scale M indicative
?
SNe confirmed literature
?
TT-CMB rejection from first peak (analytical
(Doran et al. 2000) numerical)
?
Cosmic shear (real data only)
?
  • RP strong degeneracy with SNe
  • SUGRA
  • 1) beware of systematics! (wl calibration
    when combining datasets)
  • 2) limit case prefectly known/excluded Q
    model (weakly a-dependece)

Van Waerbeke et al. (2006)
13
cosmic shear CMB variance on 8h-1 Mpc (s8)
SUGRA
Ratra-Peebles
contours follow s8 degeneracy
Spergel et al. 2006
WMAP3 weak lensing stress h,treion,normalizati
on,Wq
?
Check calibration of datasets
?
Check normalization procedure
?
Deviations from LCDM ?
14
a remark on constant w
Hoekstra et al. 2006
Spergel et al. 2006
Astier et al. 2005
Wde/Wm 0.6/0.4
zacc
zde
?
w const
15
Q by cosmic shear Fisher matrix analysis
Like previous data analysis all but (a,Wq,ns)
fixed, zs marginalized
?
CFHTLS wide/170
? SNAP
? SNAP
? DUNE
CFHTLS wide/170
? DUNE
Adding a parameter Like upper plots but treion
marginalized ? size, orientation
?
16
conclusions prospects
  • quintessence at low-z by SNe cosmic shear,
    using high-z informations (TT-CMB/Cl
    normalization)

pipeline Boltzmann code lensing code data
analysis by grid method
?
dynamical models of DE (not parameterization)
fCDM
?
consistent joint analysis of high-z (CMB) and
low-z (cosmic shear, Sne,...) observables ? no
stress between datasets no pivot redshift
?
?
for the first time cosmic shear data to this task
?
improvement bigger parameter space
?
?
? 1. combining also CMB data (high-z effects of
DE) ... 2. MCMC analysis 3.
deviation from GR, e.g. EQ ? wQ lt -1
Tereno et al. (2005)
Martin, C.S., Uzan (2005)
  • NL regime L-NL mappings (caveat)

some parameters (nS) are sensible to L-NL
mappings (? integrated effect ?), Q parameters
feel only geometry
?
  • wide field surveys are needed ? DUNE, LSST
  • deep surveys help to exploit the linear regime ?
    SKA

Schneider (1999) Chang, Réfrégier, Helfand (2004)
? Work in progress
analysis of realistic (dynamical) models of DE
using several parameters
?
other techniques cross-correlations (ISW), 3pts
functions, tomography
?
in collaboration with I.Tereno, Y.Mellier ,
J.-P. Uzan, R. Lehoucq, A. Réfrégier DUNE team
17
Thank you
18
Q by cosmic shear Fisher matrix analysis
Ratra-Peebles
SUGRA
SNe goldset
DUNE-like
TT _at_ CMB WMAP 1yr
  • A 20000 deg2
  • ngal 35/arcmin2

CFHTLS wide
  • A 170 deg2
  • ngal 20/arcmin2

All but (a,Wq) parameters fixed
?
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