Echelle spectrograph in the coude focus (ESPL) (Echelle Spectrograph Pronik Lagutin)

Characteristics of the spectrograph

Collimatorf = 6000 mm
Cameraf = 1080 mm
Echelle420×200 mm, 37.5 Grooves/mm, angle 63.5°
Grating150 Grooves/mm
Dispersion near Hα line1.39 Å/mm ≈ 0.019 Å/pixel
Spectral resolution with the entrance slit width of 0″.5R ≈ 51000
Scale1″ = 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


QE98% Max. at λ5500 Å
Geometry2048×2048 pixels (27.6×27.6 mm), 13.5 μm
Well Depth100,000 e-
Dynamic resolution16 bits, 100 kHz
Coolingup to -100°C

A detailed description of the spectrograph is to be found in the paper: Lagutin et al., 2019, Bulletin of CrAO, V. 115, P. 53-62.