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arXiv · 1602.01089

The Metal Abundances across Cosmic Time ($\mathcal{MACT}$) Survey. I. Optical Spectroscopy in the Subaru Deep Field

Chun Ly·Sangeeta Malhotra·Matthew A. Malkan·Jane R. Rigby·Nobunari Kashikawa·Mithi A. de los Reyes·James E. Rhoads
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Abstract

Deep rest-frame optical spectroscopy is critical for characterizing and understanding the physical conditions and properties of the ionized gas in galaxies. Here, we present a new spectroscopic survey called "Metal Abundances across Cosmic Time" or $\mathcal{MACT}$, which will obtain rest-frame optical spectra for $\sim$3000 emission-line galaxies. This paper describes the optical spectroscopy that has been conducted with MMT/Hectospec and Keck/DEIMOS for $\approx$1900 $z=0.1-1$ emission-line galaxies selected from our narrowband and intermediate-band imaging in the Subaru Deep Field. In addition, we present a sample of 164 galaxies for which we have measured the weak [OIII]$\lambda$4363 line (66 with at least 3$\sigma$ detections and 98 with significant upper limits). This nebular emission line determines the gas-phase metallicity by measuring the electron temperature of the ionized gas. This paper presents the optical spectra, emission-line measurements, interstellar properties (e.g., metallicity, gas density), and stellar properties (e.g., star formation rates, stellar mass). Paper II of the $\mathcal{MACT}$ survey (Ly et al.) presents the first results on the stellar mass--gas metallicity relation at $z\lesssim1$ using the sample with [OIII]$\lambda$4363 measurements.

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Chun Ly, Sangeeta Malhotra, Matthew A. Malkan, Jane R. Rigby, Nobunari Kashikawa, Mithi A. de los Reyes, James E. Rhoads. 2016-02-02. The Metal Abundances across Cosmic Time ($\mathcal{MACT}$) Survey. I. Optical Spectroscopy in the Subaru Deep Field. https://doi.org/10.3847/0067-0049%2F226%2F1%2F5

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