  The Large Array Survey Telescope (LAST) is a wide-field visible-light
telescope array designed to explore the variable and transient sky with a high
cadence. LAST will be composed of 48, 28-cm f/2.2 telescopes (32 already
installed) equipped with full-frame backside-illuminated cooled CMOS detectors.
Each telescope provides a field of view (FoV) of 7.4 deg^2 with 1.25
arcsec/pix, while the system FoV is 355 deg^2 in 2.9 Gpix. The total collecting
area of LAST, with 48 telescopes, is equivalent to a 1.9-m telescope. The
cost-effectiveness of the system (i.e., probed volume of space per unit time
per unit cost) is about an order of magnitude higher than most existing and
under-construction sky surveys. The telescopes are mounted on 12 separate
mounts, each carrying four telescopes. This provides significant flexibility in
operating the system. The first LAST system is under construction in the
Israeli Negev Desert, with 32 telescopes already deployed. We present the
system overview and performances based on the system commissioning data. The Bp
5-sigma limiting magnitude of a single 28-cm telescope is about 19.6 (21.0), in
20 s (20x20 s). Astrometric two-axes precision (rms) at the bright-end is about
60 (30)\,mas in 20\,s (20x20 s), while absolute photometric calibration,
relative to GAIA, provides ~10 millimag accuracy. Relative photometric
precision, in a single 20 s (320 s) image, at the bright-end measured over a
time scale of about 60 min is about 3 (1) millimag. We discuss the system
science goals, data pipelines, and the observatory control system in companion
publications.
