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Unformatted text preview: power spectra scale as b 2 . Since in a simple approximation, the growth rate of mass perturbations scales with the mass contribution to the cosmic density as M 0.6 , one often encounters the combination (called the redshift distortion parameter) = M 0.6 b in studies trying to solve derived density fields and galaxy distributions for b . This has the interesting property that structure amplitudes in redshift space are enhanced by a factor (1+) over those in linear coordinate space. Hamilton's review (reference above) is a nice compendium of the densityvelocity field connection, showing that values of from 0.5 to 1 are allowed by existing surveys. To confuse matters somewhat, some papers use a bias parameter that runs inversely to this convention. Analysis of the 2dF galaxy survey suggests that bias is not important on scales 530 Mpc (Verde et al. 2002 MNRAS 335, 432), with a fitted linear bias parameter of 1.04 0.11 and quadratic term 0.05 0.08. On these scales (at least), both angular and redshift clustering suggest that term 0....
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 Fall '10
 EmilyHoward
 Astronomy

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