Determining cosmological parameters with the latest observational data Hong Li TPCSF/IHEP

The cosmological observations play a crucial role in understanding universe ! CMB 、 LSS and SN Complementary, GRB and WL also make interesting progress ! Recent years Cosmology became more and more accurate There are also some ongoing ………

outline The global fitting analysis The constraints on cosmological parameters, especially the time evolving EOS of DE with CMB, LSS, SNe Constraints on EOS including GRBs & WL Testing the featured P(k) with observations Summary

Global fitting procedure  Cosmological parameters:  Method : modified CosmoMC, Perturbation included G.-B. Zhao, et al., PRD (2005)  Calculated at ShangHai Supercomputer Center (SSC)  Data: CMB, LSS, SNe ……. 1.w = constant 2. Perturbation divergent when w across -1, new method 3.

Constrains on dark energy with SN Ia (Riess) + SDSS + WMAP-1 Observing dark energy dynamics with supernova, microwave background and galaxy clustering Jun-Qing Xia, Gong-Bo Zhao, Bo Feng, Hong Li and Xinmin Zhang Phys.Rev.D73, , 2006 The importance of DE perturbation!

IHEP Constraints on EOS with WMAP3 Relative error: ~9% Relative error > 50% !! * Emphasizing the importance of the perturbation of DE * A constant EOS considered by the WMAP group

Quintessece Quintom A Quintom B Phantom Current constraint on the equation of state of dark energy WMAP5 result E. Komatsu et al., arXiv: Xia, Li, Zhao, Zhang, PRD. 78, Status: 1) Cosmological constant fits data well; 2) Dynamical model not ruled out; 3) Best fit value of equation of state: slightly w across -1  Quintom model Difference: Data: SN (SNLS+ESSENCE+Riess et al.) vs SN (307,Kowalski et al., arXiv: ) Method: WMAP distance prior vs Full CMB data. However, results similar (Li et al., arXiv: )

APJ Lett. 683, L1, 2008

For the published version : WMAP5 result E. Komatsu et al., Astrophys.J.Suppl.180: ,2009 Xia, Li, Zhao, Zhang, PRD. 78,

Preliminary results With the new CFA (SN), CBI and QUaD data:

Global analysis of the cosmological parameters including GRBs  Results from the global analysis with WMAP3+LSS+SNe(Riess 182 samples)+GRBs (Schaefer 69 sample)  New method for solution of the circulation problem

the 69 modulus published by Schaefer (in astro-ph/ )

Bias with only GRB Need global analysis

Hong Li, M. su, Z.H. Fan, Z.G. Dai and X.Zhang, astro-ph/ , Phys.Lett.B658:95-100,2008 WMAP3+LSS+SN WMAP3+LSS+SN+GRB

The relevant papers on studies with GRBs : E.L.Wright astro-ph/ F.Y. Wang, Z. G. Dai and Z. H. Zhu, astro-ph/

Problems: The circulation problem : Due to the lack of the low-redshift GRBs, the experiential correlation is obtained from the high- redshift GRBs with input cosmology !

S_r: is the fluence of the r-ray; t_j: is the Break time; n: is the circumburst particle Density; E_peak: is the peak energy of the spectrum What is the circulation problem? Due to the lack of the low-redshift GRBs, the experiential correlations are obtained from the high-redshift GRBs with input cosmology which we intend to constrain, it lead to the circulation problem! From the observation, we can get: S_r, E_peak,t_j, n With a fire ball GRB model: Ghirlanda et al.

Usually Input a cosmology Get A & C

A new method for overcoming the circulation problem for GRBs in global analysis We integrate them out in order to get the constraint on the cosmological parameter: We let A and C free: We can avoid the circulation problem ! And method can apply to the other correlations. Correlation as an example: We take Hong Li et al., APJ 680, 92 (2008)

For flat universe !

With free !

For flat universe !

The constraints on A and C related with the correlation: i.e., in the literature C is set to [0.89, 1.05]; A is set to 1.5 One can find that, this will lead to the bias to the final constraints on The cosmological parameters!

: By Nan Liang et al.

Take into account the recent weak lensing data: 100 square degree from (the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys) H.Li et al., e-Print: arXiv:

Testing Oscillating Primordial Spectrum and Oscillating Dark Energy with Astronomical Observations J.Liu, H.Li, J.-Q. Xia & X.Zhang, e-Print: arXiv: This can be motivated by: Natural inflation, Planck scale physics and oscillating primordial spectrum X.L. Wang, et al. Int.J.Mod.Phys.D14:1347,2005

The effects on the TT power spectrum and matter power spectrum

SUMMARY  The current status on determining the cosmological parameters with the data,paying particular attention to the Perturbation of DE;  Cosmological constant fits the current data well  We expect the Future observations like Planck and LAMOST will provide better constraints on the cosmological parameters ! H. Li, J.-Q. Xia, Zu-Hui Fan and X. Zhang, JCAP 10 (2008) 046