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We have obtained spectra of IRAS04296 with the CCD
(11401170 pixels) equipped echelle spectrometer
PFES mounted at the prime focus of the 6m telescope of SAO RAS
(Panchuk et al. 1998). The echelle-grating with
and with a blaze angle of
was used. A diffracton grating with
was used as the cross-disperser. The camera
has f=140mm. The size of input slit is 0.54arc sec.
We observed IRAS04296 on October 07, 1996 (JD2450363.6) and
February 26, 1997 (JD2450506.3). The echelle frames with 25
echelle-orders cover the spectral region 4420-8300Å. The average spectral
resolution was 0.4Å. The signal-to-noise ratio was in the
range 50-110 for different spectral orders.
All usual procedures needed for echelle-images reduction (bias subtraction, cosmic ray removal, optimal order extraction, rebinning) were made using the ECHELLE context of the MIDAS system. A Gaussian function approximation was made for the measurement of equivalent widths. The comparison spectrum source was an argon-filled thorium hollow-cathode lamp.
The distinctive features of the optical spectrum of the source
IRAS04296 are a peculiar profile of the line (see Fig.1), molecular emission bands and very strong
absorption lines of ionized atoms of s-process elements
(Y, Zr, Ba, La, Ce, Pr, Nd). For example, the equivalent widths
of BaII lines (6141 and 6496Å) exceed 0.6Å.