PSCz Power The PSCz is a redshift survey of 15,411 galaxies accomplished by Saunders et al. 2000. This page provides data files of measurements of the power spectrum of PSCz galaxies.

 Download the data files in a single gzip'd tar file. The measurements are described by Hamilton & Tegmark (2002) and Hamilton, Tegmark & Padmanabhan (2000). PDF (1.5MB) as published in Hamilton & Tegmark (2002) MNRAS 330(3), 506--530. ‘This is an electronic version of an article published in Monthly Notices of the Royal Astronomical Society: complete citation information for the final version of the paper, as published in the print edition of Monthly Notices of the Royal Astronomical Society, is available on the Blackwell Science Synergy online delivery service, accessible via the journal's Website at: http://www.blacksci.co.uk/MNR’. The PSCz data at linear scales, along with CMB data, are used to constrain cosmological parameters by Tegmark, Zaldarriaga & Hamilton (2001). Watch power spectrum movies.

October 2001 update: The power spectrum has been recomputed taking into account the finite 1.5 arcmin resolution of IRAS. The nonlinear power spectrum, the correlation function, and the prewhitened power spectrum are all changed from the original August 2000 values, most notably at small scales. The linear correlated and decorrelated power spectra remain unchanged.

 Real space galaxy power spectrum of PSCz. The dashed line is the flat $$\Lambda$$CDM concordance model power spectrum from Tegmark, Zaldarriaga & Hamilton (2001), nonlinearly evolved according to the prescription of Peacock & Dodds (1996). The model fits well at linear scales, but fails dismally at nonlinear scales. The PSCz power spectrum requires scale-dependent bias: all unbiased Dark Matter models (Eisenstein & Hu 1998, 1999; Ma 2000) are ruled out with high confidence. Real space correlation function of PSCz. The dashed line is a power law $$(r / 4.27 \, h^{-1} \mbox{Mpc})^{-1.55}$$. Prewhitened power spectrum of PSCz. The solid line is the (unprewhitened) power spectrum. The dashed line is the linear $$\Lambda$$CDM concordance model power spectrum from Tegmark, Zaldarriaga & Hamilton (2001). The prewhitened nonlinear power spectrum appears intriguingly similar to the linear power spectrum, as remarked by Hamilton (2000). It is not clear whether the similarity has some physical cause, or whether it is merely coincidental. Power spectrum of PSCz compared to that of APM from Gaztañaga & Baugh (1998, Table 2). The APM power spectrum has been multiplied by $$1.25$$, after Peacock (1997), to correct from the standard $$\Omega_\textrm{m} = 1$$ redshift-distance relation assumed by Gaztañaga & Baugh to a $$\Lambda$$CDM redshift-distance relation (Eisenstein & Zaldarriaga 2000). The bias is the square root of the ratio of power spectra.