Preliminary data reduction of the CCD frames, including dark subtraction and flat fielding, were done using the PMIS software, supplied by the CCD manufacturer. The spectra were then exported into IRAF and the physical parameters of the line profiles, such as equivalent widths, V/R ratios, half widths etc. were computed from it. A five point moving average or boxcar smoothing was done for all the spectra to reduce the noise, except in the case of HR 5778 where the spectrum was rather noisy and smoothing did not really help. The final spectra of the 44 Be stars are presented in Figs. 1-8.
Listed in Table 2 are the computed emission line parameters for the Be
stars.
The columns in sequential order give the HR number, the
projected rotational velocity of the star vsini in km s-1, the
equivalent width W in Angströms, the peak to continuum ratio
,
the half width (i.e. full width at half maximum) l in
Angströms, the full width at zero maximum E' in Angströms, the V/Rratio and the separation of the V and R components
in
Angströms. For maintaining uniformity, we have adopted the same
definitions for these terms as laid down in the paper of
Andrillat (1983, refer Fig. 1), except that, following
Dachs (1981), we have
used a negative sign for the equivalent width when lines are in
emission, and a positive sign in absorption. In some cases either the Vor the R component does not form a sharp peak, but a rather extended
flat/sloping region. In such cases the centre of the region has been
taken for calculating the intensity of the component and measuring
.
Such stars are marked with an asterisk in the V/Rcolumn. The majority of the mv (Table 1) and vsini values have
been taken from an electronic version of the Bright Star Catalogue
(Hoffleit & Warren 1991), but we have also referred in
some cases to Dachs (1986). It may also be noted that
HR 264 (Gamma Cas) and HR 6118 (Chi Oph) are repeated twice in
Tables 1 and 2 since their spectra were
taken at two different epochs.
We have not given the errors in the values of the above parameters for
each specific star as we feel it would suffice to give only a typical range
of them. The parameters which suffer most from the errors are the
equivalent width W and the total width E'. In the former, the
errors mainly arise when the continuum is not too well defined due to
inadequate S/N. In the case of E', on the other hand, they arise
when the lines are so broad that they seem to marginally extend beyond
the 25 Å spectral coverage of the CCD. Using several independent
measurements on IRAF, we estimate the errors in E' and W to be in
the range of 5 to 10 percent. The other parameters are better defined
and have errors in the range of 1 to 4 percent. As expected, smaller
the S/N ratio, larger the errors.
HR No. |
![]() |
Eq. Width |
![]() |
Half Width | Full Width | V/R | ![]() |
(km s-1) | W(Å) | l(Å) |
![]() |
(Å) | |||
193 | 260 | -29.5 | 6.36 | 5.27 | 13.11 | ||
264 | 300 | -22.47 | 4.12 | 6.07 | 21.33 | ||
264 | 300 | -26.72 | 4.63 | 6.62 | 23.41 | 1.25* | 2.116 |
335 | 71 | -4 | 2.12 | 3.20 | 6.86 | ||
496 | 450 | -21.88 | 3.03 | 10.69 | 24.63 | 1.01 | 4.11 |
1087 | 369 | -39 | 6.11 | 7.40 | 22.28 | 0.98 | 2.86 |
1165 | 215 | -8.62 | 2.71 | 5.08 | 12.73 | 1.02 | 1.543 |
1180 | 329 | -60.93 | 10.48 | 6.03 | 15.31 | 0.92* | 1.214 |
1273 | 217 | -28.04 | 6.74 | 4.44 | 15.17 | ||
1508 | 240 | -24.7 | 4.49 | 6.44 | 20.13 | 0.97 | 1.37 |
1622 | 131 | -19.92 | 5.80 | 3.69 | 3.94 | 0.72* | 1.3 |
1660 | 220 | -26.93 | 6.29 | 4.67 | 14.38 | ||
1789 | 316 | -15.6 | 2.71 | 9.60 | 17.92 | 1.00 | 5.64 |
1858 | 271 | -25.73 | 4.57 | 7.83 | 16.12 | 1.02 | 2.29 |
1910 | 310 | -20.64 | 3.06 | 9.80 | 22.35 | ||
1934 | 194 | -4.07 | 1.33 | 9.64 | 15.71 | 0.96 | 5.54 |
1956 | 176 | -10.36 | 2.79 | 5.43 | 12.35 | 1.00 | 1.77 |
2284 | 265 | -34.6 | 5.08 | 7.72 | 19.01 | 0.98* | 1.85 |
2343 | 219 | -3.64 | 1.73 | 7.76 | 15.86 | 0.86 | 4.07 |
2356 | 346 | -24.08 | 3.65 | 9.15 | 19.66 | 1.00 | 3.2 |
2358 | 331 | -21.1 | 3.78 | 7.30 | 19.28 | 1.32* | 2.93 |
2492 | 200 | -18.88 | 3.56 | 6.36 | 18.83 | 0.98 | 1.506 |
2538 | 199 | -15.42 | 3.19 | 6.47 | 22.25 | 0.94 | 1.95 |
2749 | 120 | -18.6 | 6.75 | 3.06 | 9.23 | ||
2787 | 220 | -28.45 | 5.46 | 5.83 | 12.54 | 1.12 | 2.11 |
2817 | 140 | -27.88 | 6.38 | 5.12 | 10.81 | ||
2825 | 33 | -11.73 | 6.45 | 2.18 | 6.44 | ||
2845 | 276 | -6.56 | 1.97 | 6.57 | 13.99 | 1.00 | 2.956 |
3135 | 148 | -46.53 | 10.13 | 4.19 | 4.41 | ||
3237 | 156 | -43.7 | 11.73 | 3.42 | 13.46 | ||
3858 | 332 | -19.7 | 2.95 | 9.18 | 20.76 | 1.00 | 2.85 |
3946 | 220 | -35.03 | 6.53 | 5.65 | 13.66 | 1.02 | 1.355 |
4621 | 181 | -35.46 | 6.89 | 5.16 | 17.66 | ||
4696 | -7.3 | 2.11 | 6.77 | 13.07 | 0.94 | 3.04 | |
4787 | 249 | -8.2 | 2.07 | 7.11 | 16.34 | 1.01 | 2.977 |
5193 | 175 | -8.75 | 2.89 | 5.12 | 10.28 | 1.03 | 1.77 |
5440 | 333 | -0.59 | 1.41 | 13.27 | 22.71 | 0.93 | 7.12 |
5778 | 393 | 2.79 | 0.76 | 10.88 | 22.93 | ||
5941 | 393 | -17.28 | 3.95 | 7.65 | 22.26 | 0.65 | 5.119 |
6118 | 134 | -35.63 | 10.58 | 13.09 | 15.86 | ||
6118 | 134 | -37.63 | 10.72 | 13.15 | 17.64 | 1.72* | 1.4 |
6510 | 298 | -19.2 | 3.26 | 8.32 | 18.71 | 1.06 | 2.83 |
6712 | 221 | -35.53 | 5.97 | 6.97 | 14.88 | 0.99 | 2.07 |
7106 | -28.36 | 4.80 | 5.80 | 21.95 | 0.58 | 5.802 | |
7763 | 75 | -51.52 | 13.83 | 4.03 | 11.48 | 0.02 | 4.44 |
8773 | 128 | -21.8 | 8.24 | 2.93 | 11.06 |
Copyright The European Southern Observatory (ESO)