Lyα Emitters at Redshift 5.7 in the COSMOS Field

Abstract

We present results from a narrowband optical survey of a contiguous area of 1.95 deg 2 , covered by the Cosmic Evolution Survey (COSMOS). Both optical narrowband (λ c = 8150 Å and Δλ = 120 Å) and broadband ( B , V , g ', r ', i ', and z ') imaging observations were performed with the Subaru prime-focus camera, Suprime-Cam on the Subaru Telescope. We provide the largest contiguous narrowband survey, targeting Lyα emitters (LAEs) at z ##IMG## [http://ej.iop.org/icons/Entities/approx.gif] {approx} 5.7. We find a total of 119 LAE candidates at z ~ 5.7. Over the wide-area covered by this survey, we find no strong evidence for large-scale clustering of LAEs. We estimate a star formation rate (SFR) density of ~7 × 10 -4 M ##IMG## [http://ej.iop.org/icons/Entities/sun.gif] {sun} yr -1 Mpc -3 for LAEs at z ##IMG## [http://ej.iop.org/icons/Entities/approx.gif] {approx} 5.7 and compare it with previous measurements.