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arXiv · 2107.11682

Searching for low-redshift faint galaxies with MMT/Hectospec

Cheng Cheng·Jia-Sheng Huang·Christopher N. A. Willmer·Hong-Xin Zhang·Matthew L. N. Ashby·Hai Xu·Marcin Sawicki·Stephane Arnouts·Stephen Gwyn·Guillaume Desprez·Jean Coupon·Anneya Golob·Piaoran Liang·Tianwen Cao·Yaru Shi·Gaoxiang Jin·Chuan He·Shumei Wu·Zijian Li·Y. Sophia Dai·C. Kevin Xu·Xu Shao·Marat Musin
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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.

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Cheng Cheng, Jia-Sheng Huang, Christopher N. A. Willmer, Hong-Xin Zhang, Matthew L. N. Ashby, Hai Xu, Marcin Sawicki, Stephane Arnouts, Stephen Gwyn, Guillaume Desprez, Jean Coupon, Anneya Golob, Piaoran Liang, Tianwen Cao, Yaru Shi, Gaoxiang Jin, Chuan He, Shumei Wu, Zijian Li, Y. Sophia Dai, C. Kevin Xu, Xu Shao, Marat Musin. 2021-07-24. Searching for low-redshift faint galaxies with MMT/Hectospec. https://doi.org/10.3847/1538-4365/ac17ef

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