# The First Data Release of the Beijing-Arizona Sky Survey

## TL;DR

The paper reports the first data release of the Beijing-Arizona Sky Survey, providing calibrated images and catalogs covering a significant sky area with detailed photometric depths in g and r bands.

## Contribution

It presents the initial data release of BASS, a new wide-field survey in the northern Galactic cap with specific imaging depths and coverage.

## Key findings

- First data release includes calibrated images and catalogs.
- Survey covers about 5400 deg$^2$ in g and r bands.
- Achieved depths of 24.1 mag in g and 23.5 mag in r after three epochs.

## Abstract

The Beijing-Arizona Sky Survey (BASS) is a new wide-field legacy imaging survey in the northern Galactic cap using the 2.3m Bok telescope. The survey will cover about 5400 deg$^2$ in the $g$ and $r$ bands, and the expected 5$\sigma$ depths (corrected for the Galactic extinction) in the two bands are 24.0 and 23.4 mag, respectively. BASS started observations in January 2015, and has completed about 41% of the whole area as of July 2016. The first data release contains both calibrated images and photometric catalogs obtained in 2015 and 2016. The depths of single-epoch images in the two bands are 23.4 and 22.9 mag, and the full depths of three epochs are about 24.1 and 23.5 mag, respectively.