Workstation. The following steps were followed for the reductions:
The error in wavelength calibration for Coudé and Cassegrain spectra was around 0.05 Å to 0.10 Å respectively. To reduce the error in normalization we normalized each spectrum, at least, three to four times and finally these spectra were averaged. Around 2% of the local continuum is estimated to be the error in normalization. The instrumental broadening was computed by measuring the FWHM of the narrowest line of the comparison spectral lines and this value of the FWHM was taken as the instrumental broadening of the spectrograph. The values of instrumental broadening for the UAGS and the Echelle spectrographs are 0.5 Å and 0.2 Å respectively, at H. These values were used to correct for instrumental broadening of the measured FWHM values of Be stars. Using the expression of (EW), given in Ghosh (1988) and Ghosh et al. (1990), the errors in equivalent width measurements were computed.
|Figure 1: Coudé Echelle H profiles of two known Be stars, HR 1037 and HR 2244. Sharp lines present throughout the spectra are H2O telluric absorption features|
|Figure 2: a) Same as Fig. 1, but for two new Be stars, HR 1544 and HR 4552. b) Same as Fig. 1, but for the new Be star, HR 1544 and the B type star HR 2155 of similar spectral type and rotational velocity as that of HR 1544. For comparison, the H profiles of these two stars are plotted one over the other and the subtracted spectrum (the H profile of HR 1544 minus the Hprofile HR 2155) is presented on the top that shows the presence of emission in the H profile of HR 1544. c) Same as Fig. 1, but for the Cassegrain spectra of five new Be stars, HR 1056, HR 2191, HR 2300, HR 3134, and HR 3878|
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