twin 1c

TWIN is a two separate channels (blue & red) spectrograph that provides  intermediate spectral resolution (R=3000-14000) in the wavelength range from 3200 to 11000 Å, by means of four beam dividers and twelve diffraction gratings.

Available at: Cassegrain station of the Zeiss 3.5 m reflector

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In a nutshell

Observing technique   Simoultaneous medium resolution spectroscopy of two bands in the visible
Dispersion   From 0.27 to 2.40 Å/pix
Wavelength range   From 3200 to 11000 Å
Slits   4 arcmin length and widths of 0.9, 1.2, 1.5, 1.8, 2.1, 2.4, 3.5 and 10.0 arcsecs
Beam dividers   4500, 5500, 6800 and 7500 Å
Gratings   270, 300, 400, 600, 830 and 1200 lines/mm
CCDs   2 SITe 2000x800 pix, 15μ (0.56")
Wavelength cal. lamps   Th-Ar, He-Ar, Ne and Fe-Ne
A&G FoV   Adq. 5x5, Slit view 4x3 arcmin


Observing with TWIN

Observer's Guide
Signal Calculator
Requesting obserrvation time for TWIN
TWIN it is not offered in 2020B semester
Service mode observing template
Night logsheet


More information

Technical data

Wavelength calibration lamps
CCDs basic parameters
CCDs linearity

Calar Alto Press releases

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