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OBSERVATIONS AND DATA REDUCTION

Spectroscopic observations of nine of the twelve objects associated either with an X-ray or a radio source (Table 2) and of 22 other FBS objects were carried out on October 27 and 28, 1997 and on May 25 and 26, 1998 with the CARELEC spectrograph [39] attached to the Cassegrain focus of the Observatoire de Haute-Provence (OHP) 1.93m telescope. A 260Åmm-1 grating was used; the spectral range was 3810-7365Å. The detector was a 512$\times$512 pixels, 27$\times$27$\mu$m Tektronix CCD. The slit width was 2$.\!\!^{\prime\prime}$1, corresponding to a projected slit width on the detector of 52$\mu$m, or 1.9 pixel. The resolution, as measured on the night sky emission lines, was 14.3Å FWHM. The spectra were flux calibrated using the standard stars EG 145 and Feige 66 [42] which were also used to correct the observations for the atmospheric absorption.

Six of the X-ray or radio sources turned out to be QSOs, while three are stars. The 22 other observed objects are all stars, except one which is a Hii galaxy. Spectra of the nine X-ray or radio sources observed are presented in Fig. 3.

The journal of observations is given in Table 3, together with relevant data.


 
Figure: Spectra of the nine observed FBS objects identified either with an X-ray or radio source.
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FBS 0732+396 was suspected of being non-stellar and having emission lines [9]. Our spectrum (Fig. 3) shows emission lines characteristic of a NLS1 galaxy at z = 0.118, with relatively narrow Balmer lines and strong Feii lines.

FBS 1255+447 is HS 1255+4445 at z = 0.30 [25].


next up previous
Next: DISCUSSION Up: ON THE NATURE OF SURVEY Previous: The Westerbork Northern Sky

3/11/1999