This high resolution spectrometer is dedicated to the investigation of extended line-emission phenomena (i.e. Supernova remnants, Planetary nebulae, HII regions, Luminous blue variable star’s nebulae, etc.)

Design:

In its primary mode a single order of its echelle grating nominally δ=63.54˚ with 31.6 grooves mm-1 is isolated by a broad, efficient, three period interference filter eliminating the need of cross-dispersion. Consequently, its primary use, is to obtain spatially-resolved profiles of individual emission lines from faint extended sources emitting in the range 3900-7500 Ǻ with a spectral resolving power of λ /Δλ ≤ 10^5.

Several secondary mode are available:

A direct image of the field can be obtained by both the insertion of a clear to replace the slit and of a mirror before the grating (slit positions against images of extended sources can be obtained using this facility).

The insertion of a grism along with the plane mirror permits long-slit, low dispersion (76.3 Ǻ/mm) spectra to be obtained.

Available filters (Barr) for MES-AT:

Parameters on the Aristarchos 2.3 m telescope (first calculated values):

ECHELLE SPECTROMETER