The clustering and evolution of Hα emitters at z ∼ 1 from HiZELS.

The clustering properties of a well-defined sample of 734 Hα emitters at , obtained as part of the Hi- z Emission Line Survey, are investigated. The spatial correlation function of these Hα emitters is very well described by the power-law , with a real-space correlation, r₀, of . The correlation length r₀ increases strongly with Hα luminosity , from for the most quiescent galaxies [star formation rates (SFRs) of ] up to for the brightest galaxies in Hα. The correlation length also increases with increasing rest-frame K-band luminosity, but the correlation maintains its full statistical significance at fixed . At , star-forming galaxies classified as irregulars or mergers are much more clustered than discs and non-mergers, respectively; however, once the samples are matched in and , the differences vanish, implying that the clustering is independent of morphological type at just as in the local Universe. The typical Hα emitters found at reside in dark matter haloes of , but those with the highest SFRs reside in more massive haloes of . The results are compared with those of Hα surveys at different redshifts: although the break of the Hα luminosity function evolves by a factor of ∼30 from to 2.23, if the Hα luminosities at each redshift are scaled by then the correlation lengths indicate that, independently of cosmic time, galaxies with the same are found in dark matter haloes of similar masses. This not only confirms that the star formation efficiency in high redshift haloes is higher than locally but also suggests a fundamental connection between the strong negative evolution of since and the quenching of star formation in galaxies residing within dark matter haloes significantly more massive than at any given epoch. [ABSTRACT FROM AUTHOR]