A subaru search for Lyman α emitters at z = 5.8 with an intermediate-band filter

We present the results of a survey for Lyα emitters at z ≈ 5.8 using a new intermediate-band filter centered at λ_c ≈ 8275 Å with Δλ_FWHM ≈ 340 Å (i.e., spectroscopic resolution is R ≈ 24) and a combination with a traditional narrow-band centered at λ_c ≈ 8150 Å with Δλ_FWHM ≈ 120 Å (R ≈ 68). Our observations were made using the Subaru Prime Focus Camera, Suprime-Cam, on the 8.2 m Subaru telescope in a sky area surrounding the high-redshift quasar SDSSp J104433.04-012522.2 at z = 5.74, covering an effective sky area of ≈ 720 arcmin². In this survey, we have found four Lyα-emitter candidates from the intermediate-band image (z ≈ 5.8 with Δz ≈ 0.3). Combined with our previous results based on the NB816 imaging, we discuss the star-formation activity in galaxies between z ≈ 5.7 and z ≈ 5.9.