the new 150 ln/mm cross-disperser for
the Echelle+CCD spectrograph
Munari, Tomov, Tomasella
Oct. 16, 1998
Spectroscopy in the near-IR (7500 Ang to 1.05
micron) is becoming increasingly important in literature, and the
log-book of the 1.82 m evidences how it is becoming more and more
interesting to Asiago observers as well.
The exploration of this spectral region at the Echelle+CCD spectrograph
has been so far performed with the 300 ln/mm cross-disperser grating.
The latter is however blazed in the blue and provides excessive order
separation in the near-IR region (forcing therefore into multiple
instrumental set-ups and exposures to cover the 7500 Ang to 1.05 micron
region). To extend the spectral coverage and increase the efficiency,
a new cross-disperser (150 ln/mm, blazed at
8000 Ang ) has been purchased and successfully mounted on the
Here we present sample Thorium, Flat and Stellar
Spectra useful to document the spectral coverage and results obtainable
with this new cross-disperser and with/without II-order suppressing filters.
A detailed new Technical Report (aimed
to revised the N.4 by Munari & Zwitter issued in September 1994) documenting
the whole spectral range of the Echelle+CCD spectrograph will be released soon.
Further details on the instrument may be found on the Asiago HomePage or
questions may be posted to the Asiago Telescope Team (GAS) at email@example.com