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AST-IHEP-CPPM-DarkEnergy: Determination of cosmological parameters
Scientific Goal: Adress open questions of fundamental cosmology:
dark matter/dark energy sector and primordial universe
•Few words about dark energy
•How to characterize dark energy
•Results already obtained by the Chinese and French groups
•Prospective
Main people involved: Charling TAO , ZHANG XinMin, André TILQUIN , ZHAO Gongbo , QIAN Zuxuan , XIA Junqing , Diane TALON , FAN Zuhui , SUN Lei, Jean Marc VIREY , LI Hong , Zhu Zhonghong , Christian MARINONI , QIN Bo . Stefan Linden , DENG Jinsong , CHAO Wu , ZHOU Xu , WANG Xiaofeng
CPPM/CPT/IHEP/PKU/NAOC/Tsinghua U/Beijing Normal U. + collaborators
Some words about cosmologyCosmology based on:
Homogenous and isotropic Universe
General relativity: G = 8GT
Energy content: = /c
Equation of state: w(z)=p/
Matter (m) : w =0
Radiation (r) : w = 1/3
Cosmological cste (): w=-1
Dark energy (X) : w(z)
(c=10-29 g/cm3)T = m + r + X
Some words about dark energyIn 1998, the Supernova Cosmology Project and High-z team shown that high red-shift supernovae are fainter than expected: a new energy component is needed.
Definition: c (c=10-29
g/cm3)
Z
Dark energy or cosmological constant caracterized by reduce density: c
For a flat Universe:
05.009.004.008.072.0
From observations to the Concordance Model
CMB(WMAP)
SNe Ia
LSS
Universe is mainly dark
~70% DE
and
~25% DM.
a 2006 status
Definition: c (c=10-29
g/cm3)
What is this Dark Energy?
Cosmological Constant???
New form of « field/matter? » Quintessence?
Unified Dark Matter?
Modified Gravity/GR ?
- Non minimal Couplings?
- Extra-Dimensions?
- Anisotropy/ inhomogeneity effects?
- Negative energy?
Characterized by its equation of state w=p/ = w0+waz/(1+z)
1/ 0 wpw
)(/ zwpw
effectif )(/ zwpw
How to extract w0,wa?
Cluster counts
Supernovae
Baryon Wiggles
Cosmic ShearAngular diameter distance
Growth rate of structure
Evolution of dark matter perturbations
Angular diameter distance
Standard candleLuminosity distance
Evolution of dark matter perturbationsAngular diameter distanceGrowth rate of structure
CMB Snapshot at ~400,000 yr, viewed from z=0Angular diameter distance to z~1000Growth rate of structure (from ISW)
Degeneracies between parameters imply multi-probes analysis sensitive to complementary quantities: Luminosity distance, angular distance, growth factor…
Important number of parameters (cosmological/astrophysical)
b/m density for baryon/matter/ nr density for neutrino’sk curvature density•h Hubble constant,•ns spectral index,• reionisation optical depth • A(~8
2) normalization for CMB, WL and BAO. •ms0 normalization for SNIa.•yhe Helium fraction•w0,wa Equation of state….
•Efficient statistical tools needed:
•Bayesian statistic and MCMC : Chinese and astrophysicist choice
•Frequentist statistic and datagrid : French and particle physicist choice
Both groups made similar studies.
Dark energy with or without perturbations
Frequentist
CPPM/CPT
SaclayAstro-ph/050717
Bayesian
IHEP
Astro-ph/060362
Dynamics of dark energy and curvature of universe WMAP3
astro-ph/061272: IHEP/PKU/BNU/CPPM/CPT
28.093.2
44.039.00
043.0043.0
944.0
053.1
015.0
error 2
a
k
w
w
Cosmological constraint using BAO
Data
CDM
Results obtain during my 3 months stay to Beida University
•ESR+Euchina virtual organization and ZEN program (CPPM)
•BAO from BAOfit (Sun Lei from PKU. Join PhD)
ESR VO ESR+EUchina VORiess 2006
40000 hours of CPU
Data
CDM
Diane Talon-Esmieu10000 hours of CPU
Data grid progress•Installation of a Resource-broker, a SE at IHEP for the ESR (Earth Science Research) virtual organization. 4 machines at IHEP run our application.
•Members of Euchina VO
•Open CPPM machines to the Euchina virtual organization
Future program•Phenomenological/theoretical aspects
•Use new probes, WL,SDSS…
•Use new theories (MG) or new classes of dark energy models
•Experimental aspects
•Systematical error studies and bias, i.e catastrophic redshift,SN evolution..
•Wait for new data, I.e SNLS 3 years
•Technical aspect:
•Implement MCMC on datagrid
•Reinforce collaboration on European (ESR..) and EUchina datagrid
•Human aspect:
•Need other long term missions
•Need students
Technical progress (Datagrid).
Our main goal was to re-enforce
the connexion between
Europe and China
Technical progress (2)•Installation of a User Interface (UI) at Beida with 2 Graphical Interfaces
Prepare and send jobs in the euchina grid Control the jobs and get job
output
Technical progress (3)•Installation of a Resource-broker (jobs driver) and a Storage-element at IHEP for the ESR virtual organization.
European program from ESR can run on Chinese machines
•Opening of 4 machines at IHEP to run ESR applications (thanks to Zuxuan for negotiations). Our ZEN program runs on these machines.
You want to make virtual
travels ? Go to virtual
organization on datagrid
Technical progress (4)•Installation of the ZEN program on the euchina grid (we are now members)
•Opening of Marseille machines to the euchina virtual organization
Chinese programs can run at Marseille (and also in Europe).
Other scientific results
GALAXY DISTRIBUTION AS A PROBE OF THE RINGLIKE DARK MATTER
STRUCTURE IN THE GALAXY CLUSTER CL 0024+17
(Pr. Bo Qin, Huan-Yuan Shan)
The ring dark matter structure observed with lensing, is unlikely
confirmed by galaxies distribution.
Paper in preparation but still some work to simulate completeness of the
galaxies survey from CFHT/WHT (A&A 372, 391{405 (2001)}
Simulation