Euclid实验数据对相互作用暗能量模型的预测限制

Forecasting the interaction in dark matter-dark energy models from Euclid-like galaxy survey

模拟了加入非线性理论不确定性误差的Euclid巡天数据,同时结合宇宙微波背景辐射(CMB)、BAO和Ia型超新星(SNe Ⅰa),利用马尔可夫链蒙特卡洛(MCMC)算法,在完整的参数空间下对wCDM模型进行预测限制,对暗能量与暗物质间的相互作用性质进行探讨.为了研究Euclid巡天项目对不同相互作用暗能量模型的耦合常数(β)、暗能量状态方程(w)等参数的限制效果,采用CMB+BAO+SNe Ia和Euclid+CMB+BAO+SNe Ia数据组合对4个相互作用暗能量模型进行了限制对比,得到结论如下:1)除了Qde ∝ 3βHρdevde模型,其他模型在加入Euclid模拟数据后,模型参数均得到了更好的限制.2)在各个模型中,用CMB+BAO+SNe Ia数据组合限制时,β均在1.2σ置信区间内不为0;当用Euclid+CMB+BAO+SNe Ia数据组合限制时,在Qde∝3βHρcvc、Qde∝3βHρcvde、Qde∝3βρdevc这3个模型中,均在1σ置信区间内不为0;在Qde∝3βHρdevde模型中,β在1.9σ置信区间内不为O.Euclid巡天实验结合CMB、超新星、哈勃参量的直接测量等宇宙学探针,将会帮助进一步了解暗能量、暗物质性质.

Euclid is a European Space Agency(ESA) plan to start space galaxy survey in 2022.ESA will use two complementary cosmological probes to capture signatures of the expansion rate of the Universe and the growth of cosmic structures-galaxy clustering and cosmic shear,to study the dark energy model of interaction.Here we simulate Euclid galaxy survey data with nonlinear theoretical uncertainty error,and use Markov Chain Monte Carlo(MCMC)algorithm to constrain interacting dark energy model(wCDM) in complete parameter space with cosmic microwave background radiation(CMB),baryonic acoustic oscillation(BAO) and type Ⅰa supernovae(SNe Ⅰa).To study restriction ability of Euclid on coupling constant(β),dark energy equation of state(w) and other parameters of different interaction dark energy models,we compared four interaction dark energy models with CMB+BAO+SNe and Euclid+CMB+BAO+SNe.Euclid+CMB+BAO+SNe were found to give more stringent constraints on interacting dark energy models except Qde∝3βHρdevde.With CMB+BAO+SNe,deviations of β from 0 were found to be>1.2σ for all four models.With Euclid+CMB+BAO+SNe,deviations of β from 0 were>1σ for models of Qde∝3βHρcvc,Qde∝3βHρcvde,Qde∝3βHρdevc,but were>1.96 for Qde∝3βHρdevc.Euclid is a potential survey experiment,combined with CMB,SNe,Hubble parameter data(OHD) and other cosmological probes.Euclid will help to further understand properties of dark energy and dark matter.