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Power Spectrum Analysis of the 2dF QSO Sample Revisited

Kazuhiro Yamamoto
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Abstract

We revisit the power spectrum analysis of the complete sample of the two degree field (2dF) QSO redshift (2QZ) survey, as a complementary test of the work by Outram et al. (2003). A power spectrum consistent with that of the 2QZ group is obtained. Differently from their approach, fitting of the power spectrum is investigated incorporating the nonlinear effects, the geometric distortion and the light-cone effect. It is shown that the QSO power spectrum is consistent with the $Λ$ cold dark matter (CDM) model with the matter density parameter $Ω_m=0.2\sim0.5$. Our constraint on the density parameter is rather weaker than that of the 2QZ group. We also show that the constraint slightly depends on the equation of state parameter $w$ of the dark energy. The constraint on $w$ from the QSO power spectrum is demonstrated, though it is not very tight.

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Kazuhiro Yamamoto. 2004-01-06. Power Spectrum Analysis of the 2dF QSO Sample Revisited. https://doi.org/10.1086/382496

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