Skip to main content
eScholarship
Open Access Publications from the University of California

UC Davis

UC Davis Previously Published Works bannerUC Davis

Spectroscopically Confirmed Lyα Emitters from Redshift 5 to 7 behind 10 Galaxy Cluster Lenses

  • Author(s): Fuller, S;
  • Lemaux, BC;
  • Bradač, M;
  • Hoag, A;
  • Schmidt, KB;
  • Huang, K;
  • Strait, V;
  • Mason, C;
  • Treu, T;
  • Pentericci, L;
  • Trenti, M;
  • Henry, A;
  • Malkan, M
  • et al.
Abstract

We present 36 spectroscopically confirmed intrinsically UV-faint Lyα-emitting galaxies from follow-up observations with Keck/DEep Imaging Multi-Object Spectrograph of gravitationally lensed high-redshift candidates. Candidates were selected to be between 5 ≲ z ≲ 7 from photometric data using Hubble Space Telescope and Spitzer imaging surveys. We performed an integrated photometric redshift probability cut >1% between 5 < z < 7 to construct a sample of 198 high-redshift objects. Our sample spans intrinsic UV luminosities from a few L∗ down to 0.001L∗. We identified 19 high-confidence detections and 17 likely detections of Lyα. We divided our sample into lower-redshift (z ∼ 5.5) and higher-redshift (z ∼ 6.5) bins and ran Monte Carlo trials, incorporating the strengths of the Lyα emission and the photometric redshifts of the nondetections. Considering only objects where Lyα could be detected at EW(Lyα) > 25 Å at 3σ at the fiducial depth of our survey, and only those galaxies with EW(Lyα) > 25 Å, and only objects with m AB < 26.8, we found the Lyα emitter (LAE) fraction to be flat or modestly increase from 0.26 0.04 to 0.30 0.04. These values are consistent with a rising LAE fraction with redshift out to z ∼ 6, but at z ∼ 6.5, there is some tension between our results and results from surveys at intrinsically brighter luminosities. We conclude that intrinsically fainter galaxies have Lyα emission, and there is a steep drop in the LAE fraction from our high-redshift sample at z ∼ 6.5 and from similar galaxies at z ∼ 7.5. This likely indicates we are witnessing the tail end of the epoch of reionization, as such a drop is not expected due to changes of intrinsic galaxy properties between these redshifts.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View