The Subaru FMOS Galaxy Redshift Survey (FastSound). II. The Emission Line Catalog and Properties of Emission Line Galaxies

TL;DR

The FastSound survey cataloged approximately 3,300 emission line galaxies at redshift 1.2-1.5, providing insights into their properties, large-scale distribution, and emission line contamination, with data made publicly available.

Contribution

This paper introduces the first comprehensive catalog of emission line galaxies from the FastSound survey, including their properties, spatial distribution, and contamination estimates.

Findings

Detected ~3,300 emission line galaxies at z~1.2-1.5.

Mapped large-scale galaxy clustering over 100-600 Mpc scales.

Estimated 4% contamination of non-Hα lines in single-line detections.

Abstract

We present basic properties of $\sim$3,300 emission line galaxies detected by the FastSound survey, which are mostly H$\alpha$ emitters at $z \sim$ 1.2-1.5 in the total area of about 20 deg$^2$, with the H$\alpha$ flux sensitivity limit of $\sim 1.6 \times 10^{-16} \rm erg \ cm^{-2} s^{-1}$ at 4.5 sigma. This paper presents the catalogs of the FastSound emission lines and galaxies, which will be open to the public in the near future. We also present basic properties of typical FastSound H$\alpha$ emitters, which have H$\alpha$ luminosities of $10^{41.8}$-$10^{43.3}$ erg/s, SFRs of 20--500 $M_\odot$/yr, and stellar masses of $10^{10.0}$--$10^{11.3}$ $M_\odot$. The 3D distribution maps for the four fields of CFHTLS W1--4 are presented, clearly showing large scale clustering of galaxies at the scale of $\sim$ 100--600 comoving Mpc. Based on 1,105 galaxies with detections of multiple emission lines, we estimate that contamination of non-H$\alpha$ lines is about 4% in the single-line emission galaxies, which are mostly [OIII]$\lambda$5007. This contamination fraction is also confirmed by the stacked spectrum of all the FastSound spectra, in which H$\alpha$, [NII]$\lambda \lambda$6548,6583, [SII]$\lambda \lambda$6717, 6731, and [OI]$\lambda \lambda$6300,6364 are seen.