Development of the Sun Yat-Sen University 1.2-m Multi-Terminal Telescope

The Sun Yat-Sen University (SYSU) 1.2-m Multi-Terminal Telescope is a versatile astronomical facility with three-channel photometric and low-/high-resolution spectrometric functions. The SYSU telescope comprises a Ritchey-Chretien Cassegrain bi-reflection system with a working waveband ranging from 300 to 1000 nm. Within the field-of-view (FOV) of 15', the image quality represented in 80% encircled light energy is concentrated within 0.3 arcsec. A Cassegrain instrument unit is mounted on a telescope derotator that enables working modes to be switched among four instruments by a central switching mirror. The equipped instruments include a three-channel photometric terminal, a 1.25-inch visual observation terminal, a wavelength calibration unit, a long-slit spectrograph (LSS), and a fiber adaptor for high-resolution observation. Therein, the photometric terminal can perform simultaneous imaging in the b(320-450 nm), g(480-700 nm), and r(730-1000 nm) bands. By adding a set of corrective lenses, the visual observation terminal can also realize a large FOV of 0.76 degrees. The LSS can provide high-throughput observation, with the resolution ranging from 1000 to 3000 by slit width. A high-resolution spectrograph (HRS) at the laboratory is fed by a 25-m fiber from the Cassegrain fiber adaptor. The resolution R of the HRS exceeds 30,000 to cover a wide band from 400 to 900 nm. The SYSU 1.2-m Multi-Terminal Telescope combines excellent photometric and spectrometric observational performances. The novel design of the SYSU telescope allows for a singular telescope to make contributions in both astronomical education and scientific research.