The MAGIC Project. I. High-Resolution Spectroscopy on SALT Telescope and the Cepheid RS Nor as a Test Object
We briefly describe the large MAGIC observational project aimed at mass spectroscopic studies of stars of different subsystems of our Galaxy. The project was carried out on the Southern African Large Telescope (hereafter referred to as SALT) with efficient use of its capabilities, astronomical climate, and spectroscopic instruments. We discuss in detail the issues of high-resolution spectroscopy when studying the chemical composition of Galactic Cepheids. Observations of these objects with HRS echelle spectrograph of SALT telescope started in 2016 and currently the number of such observations exceeds one hundred. Spectra were acquired in the medium-resolution mode (R ~ 36 500-39 000) with a high signal-to-noise ratio (S/N~50-220). The spectroscopic images acquired were reduced with a package that we developed based on standard MIDAS system. We describe standard reduction steps using the Cepheid RS Nor as a test object. Based on the data of spectroscopic observations we determined the atmospheric parameters and the abundances of 31 chemical elements (36 neutral atoms and ions) whose absorption lines are observed in the spectrum of RS Nor. We performed all computations using two methods and showed that echelle spectra acquired in the medium-resolution mode can be used to study the chemical composition of Cepheids with good accuracy and that the results agree with the results of other studies within the quoted errors.