2.6-m Shajn Telescope (ZTSh)
2.6-meter reflector ZTSh named after academician G.A. Shajn is the main optical telescope of CrAO. It was built in 1961 by the Leningrad Optical and Mechanical Association (LOMO). The chief designer was B.K. Ioannisiani.
| Primary mirror diameter | 2.6 m |
| Focal length | 10 m |
| Optical systems: |
Primary focus (f/3.85), Cassegrain focus (f/16), Nasmyth focus (f/16) Coude focus (f/40) |
| Equipment: |
Spectrograph SPEM in the Nasmyth focus Spectrograph ASP-14 in the coude focus Echelle spectrograph in the coude focus (ESPL) CCD-camera in the primary focus |
| Coordinates | 44°43′41″ N; 34°00′57″ E |
Equipment
Spectrograph SPEM in the Nasmyth focus
Characteristics of the spectrograph
| Collimator | f/16, D = 80 mm |
| Maksutov camera | f/2.5 |
| Diffracting gratings | 651 и 1200 Grooves/mm (150×150 mm) |
| Dispersion near Hα line with grating of 651 gr/mm | 1.76 A/pixel; 2465 A per frame |
| Spectral resolution with the entrance slit width of 3″ and with grating of 651 gr/mm | 7.5 ? |
| Scale | 0.78 arcsec/pixel |
| Exposure for Seyfert galaxies of 13-14m with grating of 651 gr/mm | 15-20 minutes (S/N > 100) |
Detector - CCD camera SPEC-10 (Roper Scientific, USA)
Characteristics
| Readnoise | 1.50 ADU = 2.98 e- |
| Gain | 1.99 e-/ADU |
| QE | 95% Max. at λ5500 A |
| Geometry | 1340×100 pixels, 20×20 μm |
| Well Depth | 262,000 e- |
| Dynamic resolution | 16 bits, 100 kHz |
| Cooling | up to -100°C, regardless of ambient |
Spectrograph ASP-14 in the coude focus
Characteristics of the spectrograph
| Collimator | f/40 |
| Camera | f/12 |
| Diffracting gratings | 600 Grooves/mm |
| Dispersion near Hα line | 2.4 A/pixel |
| Spectral resolution with the entrance slit width of 0″.5 | R ≈ 30000 |
A detailed description of the spectrograph is to be found in the paper: Vasilyev, A.S., 1986, Bulletin of CrAO, V. 55, P. 224-235.
Spectrograph ASP-14 is not currently used.
Echelle spectrograph in the coude focus (ESPL) (Echelle Spectrograph Pronik Lagutin)
Characteristics of the spectrograph
| Collimator | f = 6000 mm |
| Camera | f = 1080 mm |
| Echelle | 420×200 mm, 37.5 Grooves/mm, angle 63.5° |
| Prism | 34° |
| Grating | 150 Grooves/mm |
| Dispersion near Hα line | 1.39 A/mm ≈ 0.019 A/pixel |
| Spectral resolution with the entrance slit width of 0″.5 | R ≈ 51000 |
| Scale | 1″ = 0.083 mm ≈ 6 pixel |
| Exposure for stars of 10m (slit width of 0″.5) | 30 minutes (S/N ≈ 50 near Hα line) |
Detector: CCD camera Andor iKon-L 936
Characteristics
| QE | 98% Max. at λ5500 A |
| Geometry | 2048×2048 pixels (27.6×27.6 mm), 13.5 μm |
| Well Depth | 100,000 e- |
| Dynamic resolution | 16 bits, 100 kHz |
| Cooling | up to -100°C |
CCD camera in the primary focus
Characteristics
| Sensor | KAF-1001E |
| Focusing device | FLI DF-2 |
| Filter wheel | CFW with BVRI filters |
| Frame size | 1024×1024 pixels, 8′.4×8′.4 |
| Pixel size | 24 microns, 0″.5/pixel |
| Achieving magnitude with a total exposure of about an hour (by summing several dozen frames) | 24m.5 (V band) |