The DWT power spectrum analysis of the large scale structure in the universe : Method and simulation tests |
| |
Authors: | YANG Xiaohu FENG Longlong CHU Yaoquan |
| |
Institution: | Center for Astrophysics, University of Science and Technology of China, Hefei 23 0026, China; National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China |
| |
Abstract: | Based on the discrete wavelet transformation ( DWT), we present a pixelized method of estimating the power spectra of galaxy
samples. With local properties of wavelet both in physical and wavenumber spaces, DWT power spectrum is equal to the corresponding
band average of Fourier power spectrum. The DWT estimator is optimized in the sense that the spatial resolution is adaptive
automatically to the perturbation wavelength to be studied. Under the assumption of ergodicity, the spatial average of local
DWT fluctuation modes provides a fair estimation of the ensemble average. We test DWT spectra of four typical cold dark matter
(CDM) structure formation models with numerical simulations. To consider the infections of various observation effects to
the DWT spectra, we introduce irregular survey geometries, a given sampling rate, radial selection effects and redshift distortion
effects into our mock samples. The numerical results show that, owing to its local properties, DWT spectrum is less affected
by the sampling rate, survey geometry, and statistical ensemble fluctuations. With fast wavelet decomposition algorithm, DWT
can be used to analyze large survey samples, which is of direct significance in precise measurement of the cosmological parameters
from the galaxy redshift surveys of next generation. |
| |
Keywords: | large-scale structure N-body simulation redshift survey |
本文献已被 万方数据 SpringerLink 等数据库收录! |
|