Search for z ∼ 6.96 Lyα emitters with Magellan/IMACS in the cosmos field

We report a search for z ∼ 6.96 Lyα emitters (LAEs) using a narrowband filter, centered at 9680 Å with the Inamori-Magellan Area Camera and Spectrograph instrument on the Magellan telescope at Las Campanas Observatory. We obtain a sample of six LAE candidates of luminosity ∼10 ⁴² erg s^-1 in a total area of 465 arcmin² corresponding to a comoving volume of ∼72,000 Mpc³. From this result, we derive a Lyα luminosity function (LF) at z ∼6.96 and compare our sample with the only z ∼6.96 LAE spectroscopically confirmed to date. We find no evolution between the z = 5.7 and z ∼7 Lyα LFs if a majority of our candidates are confirmed. Spectroscopic confirmation for this sample will enable more robust conclusions.