The 2dF QSO Redshift Survey — XI. The QSO power spectrum

We present a power spectrum analysis of the final 2dF Quasi-Stellar Object (QSO) Redshift Survey catalogue containing 22 652 QSOs. Utilizing the huge volume probed by the QSOs, we can accurately measure power out to scales of ∼500 h −1 Mpc and derive new constraints, at z ∼ 1.4, on the matter and baryonic contents of the Universe. Importantly, these new cosmological constraints are derived at an intermediate epoch between the cosmic microwave background observations at z ∼ 1000, and local (z ∼ 0) studies of large-scale structure; the average QSO redshift corresponds to a look-back time of approximately two-thirds of the age of the Universe. We find that the amplitude of clustering of the QSOs at z ∼ 1.4 is similar to that of present-day galaxies. The power spectra of the QSOs at high and low redshift are compared and we find � � �