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تسجيل مستخدم جديدSearching for low-redshift faint galaxies with MMT/Hectospec
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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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