dwtpowerspectrumofthetwodegreefieldgalaxyredshiftsurvey

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	dwtpowerspectrumofthetwodegreefieldgalaxyredshiftsurvey
	YanChuan Cai 2; Jun Pan 2; YongHeng Zhao 3; LongLong Feng 2; LiZhi Fang 1
刊名	chineseastronomyandastrophysics
	2008
卷号	8 期号:2 页码:159
ISSN号	0275-1062
英文摘要	The power spectrum of the two-degree Field Galaxy Redshift Survey (2dFGRS) sample is estimated with the discrete wavelet transform (DWT) method. The DWT power spectra within 0.035 < k < 2.2 h Mpc-1 are measured for three volume-limited samples de-fined in consecutive absolute magnitude bins -19 ～-18, -20～ -19 and -21～-20. We show that the DWT power spectrum can effectively distinguish ACDM models of σs = 0.84 and σ8 = 0.74. We adopt maximum likelihood method to perform three-parameter fitting of the bias parameter b, pairwise velocity dispersion σpv and redshift distortion parame-ter β = Ω0.6m/b to the measured DWT power spectrum. The fitting results state that in a σ8= 0.84 universe the best-fit values of σm given by the three samples are mutually consis-tent within the range 0.28 ～ 0.36, and the best fitted values of σpv are 398+35-27475+37-29 and 550 ± 20km s-1 for the three samples, respectively. In the model of σ8 = 0.74, our three samples give very different values of Ωm. We repeated the fitting using the empirical formula of redshift distortion. The result of the model of low σ8 is still poor, especially, one of the best-fit values of σpv is as large as 103 km s-1. We also repeated our fitting by incorporating a scale-dependent galaxy bias. This gave a slightly lower value of Ωm. Differences between the models of σ8 = 0.84 and σ8 = 0.74 still exist in the fitting results. The power spectrum of 2dFGRS seems to disfavor models with low amplitude of density fluctuations if the bias parameter is assumed to be scale independent. For the fitting value of Ωm to be consistent with that given by WMAP3, strong scale dependence of the bias parameters is needed.
语种	英语
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/38723]
专题	中国科学院国家天文台
作者单位	1.亚利桑那大学 2.中国科学院紫金山天文台 3.中国科学院国家天文台
推荐引用方式 GB/T 7714	YanChuan Cai,Jun Pan,YongHeng Zhao,et al. dwtpowerspectrumofthetwodegreefieldgalaxyredshiftsurvey[J]. chineseastronomyandastrophysics,2008,8(2):159.
APA	YanChuan Cai,Jun Pan,YongHeng Zhao,LongLong Feng,&LiZhi Fang.(2008).dwtpowerspectrumofthetwodegreefieldgalaxyredshiftsurvey.chineseastronomyandastrophysics,8(2),159.
MLA	YanChuan Cai,et al."dwtpowerspectrumofthetwodegreefieldgalaxyredshiftsurvey".chineseastronomyandastrophysics 8.2(2008):159.