AstroLab SAO
Main Stellar Spectrograph (MSS)

MSS is a part of the spectral complex (NES, LYNX, MSS) having a common control.
This complex is located at the Nasmyth-2 focus platform of the 6-m telescope.

MSS has been produced by the Optic-Mechanical Corporation, Leningrad, in 1973. Optical elements have been designed mainly at the Vavilov Optical State Institute, Leningrad. Some details of the construction were published by Vasil'ev A.S. et al (Optiko-Mekhanicheskaja Promyshlennost', 1977, v.2, p.31).

The focal length of the collimator is F=7929mm.
The diameter of the collimated beam is d=258mm.

There are four gratings of different blaze angles, having 600 gr/mm and a blazed area 300x200mm, and working in I-IV orders of diffraction.

There are two Schmidt cameras with a focal length of F=600mm and F=300mm. The correction plates for UV are produced from fused silica.

In 1991 the Schmidt camera (F:2.3) was modified by the Stellar Spectroscopy Laboratory for using of new detectors (a two-dimensional photon counting system, CCD's). The F:1.2 camera is being now in the reconstruction.

The optical layout of MSS with the Schmidt camera (F:2.3)(without its preslit devices) is presented here.

The preslit devices are presented here.

The CCD and image recording are controlled with a PC inside the environment of OS Linux. Spectra are available for users in FITS format.

The photo of the spectrograph is presented here.

More details and main parameters of MSS you could find in: V.E. Panchuk. Main Stellar Spectrograph of the 6-m telescope. The camera F:2.3 with a CCD. SAO Technical Report, 1998, N.258, (in Russian).

To illustrate some possibilities of MSS the results of the programme of spectroscopy of absorptional spectra of bright QSO's (by Prof. D.A. Varshalovich, Ioffe Institute, St.Petersbourgh) could be recommended.

In nearest future we plan an upgrade of MSS. In particular, 3 new diffraction gratings with ruled area 360x320mm are already produced.

For consultations or other requests, please, contact with Dr. Ivan Najdenov: