Upgraded Photometric System of The 85-cm Telescope at Xinglong Station

TL;DR

This paper reports on the upgrade of the 85-cm telescope at Xinglong Station, including new optics, filters, and camera, along with calibration and performance testing results to enhance its scientific capabilities.

Contribution

It presents the first comprehensive calibration and performance evaluation of the upgraded system, improving the telescope's observational accuracy and efficiency.

Findings

Calibration coefficients derived for UBVRI bands.

Measured limiting magnitudes for various exposure times.

Performance metrics including bias, dark current, and gain.

Abstract

The 85-cm telescope at the Xinglong station is a well-operated prime focus system with high science outputs. The telescope has been upgraded since 2014 with new corrector, filters and camera, which are provided by Beijing Normal University (BNU). The filter set is Johnson-Cousins UBVRI system. We report the test results of the new system including the bias, dark current, linearity, gain and readout noise of the CCD camera . Then we derive accurate instrumental calibration coefficients in UBVRI bands with Landolt standard stars in the photometric nights. Finally, we give the limiting magnitudes with various exposure time and signal-to-noise ratio for observers as references.