Searching for low-redshift faint galaxies with MMT/Hectospec

TL;DR

This study provides redshifts and spectral data for over 2,700 low-redshift faint galaxies, enabling detailed analysis of their properties and contributing valuable data for galaxy evolution research.

Contribution

First large-scale spectroscopic survey of low-redshift faint galaxies using MMT/Hectospec, with detailed data on ages, metallicities, and activity levels.

Findings

Confirmed effectiveness of low-redshift galaxy selection technique.

Provided high-quality spectra for galaxies down to stellar masses of 10^8 M_sun.

Enhanced understanding of galaxy properties in key survey fields.

Abstract

We present redshifts for 2753 low-redshift galaxies between $0.03 \lesssim z_{\rm spec}\lesssim0.5$ with 18 $\leq$ $r$ $\leq$ 22 obtained with Hectospec at the Multi-Mirror Telescope (MMT). The observations targeted the XMM-LSS, ELAIS-N1 and DEEP2-3 fields, each of which covers $\sim$ 1 deg$^2$. These fields are also part of the recently completed CFHT Large Area U-band Deep Survey (CLAUDS) and on-going Hyper Suprime-Cam deep fields surveys. The efficiency of our technique for selecting low-redshift galaxies is confirmed by the redshift distribution of our sources. In addition to redshifts, these high S/N spectra are used to measure ages, metallicities, and nuclear activity levels. In combination with the photometric catalogue in $u$, $g$, $r$, $i$, $z$, $y$ down to 27 AB mag, we are able to study the galaxy population down to stellar masses of $\sim$ 10$^8 M_\odot$ . This paper presents the observational strategy, the reduction procedure and properties of the galaxy sample.