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2. Observations

Forty-seven high-resolution spectra (35 in Htex2html_wrap_inline1200 and 12 in Htex2html_wrap_inline1202) were obtained in July 16-20, 1991 and in July 25-27, 1992 with the Coudé Echelle Spectrometer (CES) installed at the 1.4 m Coudé Auxiliary Telescope (CAT) of the European Southern Observatory (ESO) at La Silla (Chile). An RCA CCD was used as detector and a spectral resolving power tex2html_wrap_inline1274 was ensured for all the spectra. A detailed description of the observational data, their reduction and analysis are given in Paper I.

Besides of that, 16 spectra near Htex2html_wrap_inline1200 and 6 spectra in the region of the He I 5876 and DNaI lines were obtained at the Astrophysical National Laboratory of Brazil in 1992-1995. The observations were carried out using the coudé spectrograph of the 1.6m telescope equipped with a tex2html_wrap_inline1278 pixels CCD detector. A spectral resolving power R of 15000 and S/N ratio of about 200 (near the continuum level) were achieved in each spectrum with the wavelength coverage tex2html_wrap_inline1284 of about 150 Å.

The reduction process follows the standard procedure as described by Wagner (1992), using the IRAF package.

About 50 polarimetric estimates in the tex2html_wrap_inline1286 bands were obtained in July 17-31, 1995 at the SAAO with the UCT-polarimeter (Cropper 1985), attached to the 0.75m telescope. The polarimeter module contains a half-wave and a quarter-wave plate rotating in opposite directions, allowing simultaneous linear and circular polarization measurements. All observations were made with tex2html_wrap_inline1288 aperture. The polarimeter was calibrated using polarimetric standards of Hsu & Breger (1984). Data reduction was performed in the Keele University using the suite of programs which was created at the SAAO.



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