SIMBAD references

New results from a large survey of Hα emission-line galaxies at z = 0.84 using the Wide Field Camera on the United Kingdom Infrared Telescope and a custom narrow-band filter in the J band are presented as part of the High-z Emission Line Survey (HiZELS). The deep narrow-band images reach an effective flux limit of F_Hα∼ 10^–16erg/s/cm2 in a comoving volume of 1.8x10⁵Mpc³, resulting in the largest and deepest survey of its kind ever done at z ∼ 1. There are 1517 potential line emitters detected across ∼1.4 deg², of which 743 are selected as Hα emitters, based on their photometric and spectroscopic redshifts. These are then used to calculate the Hα luminosity function, which is well fitted by a Schechter function with L* = 10^42.26±0.05erg/s, φ* = 10^{–1.92±0.10}/Mpc3 and α = -1.65±0.15, and are used to estimate the volume average star formation rate (SFR) at z = 0.845, ρ_SFR: 0.15±0.01M_☉/yr/Mpc3 (corrected for 15 per cent active galactic nucleus contamination and integrated down to 2.5M_☉/yr). These results robustly confirm a strong evolution of ρ_SFR from the present day out to z ∼ 1 and then flattening to z ∼ 2 using a single star formation indicator: Hα luminosity. Out to z ∼ 1, both the characteristic luminosity and space density of the Hα emitters increase significantly; at higher redshifts, L* continues to increase, but φ* decreases. The z = 0.84 Hα emitters are mostly disc galaxies (82±3 per cent), while 28±4 per cent of the sample shows signs of merger activity; mergers account for ∼20 per cent of the total integrated ρ_SFRat this redshift. Irregulars and mergers dominate the Hα luminosity function above L*, while discs are dominant at fainter luminosities. These results demonstrate that it is the evolution of `normal' disc galaxies that drives the strong increase in the SFR density from the current epoch to z ∼ 1, although the continued strong evolution of L* beyond z = 1 suggests an increasing importance of merger activity at higher redshifts.