Up: Nine newly discovered bright
The spectroscopic observations were made in several observing runs in 1996 and
1997 with the 2.16 m telescope of the United Laboratory of Optical Astronomy,
Chinese Academy of Sciences at Xinglong Station, Beijing Astronomical
Observatory (BAO). The spectra were obtained with the OMR spectrograph
equipped with a Tektronix CCD (
pixels with 24 microns per
pixel) at a dispersion of 200 Å mm-1 or 400 Å mm-1.
The 400 Å mm-1 grating was not used if one believes Table 1. The
spectral coverage was 3800 - 8200 Å. The journal of observations is given
in Table 1.
The data reduction was performed by using the IRAF program package. The CCD
reductions included bias subtraction, flatfield correction and cosmic-ray
removal. Spectra of a He-Ne-Ar or Fe-Ar lamp were taken to get an absolute
wavelength scale. The flux calibration was derived with 2 to 3 observations
of KPNO IIDS standard Stars (Strom 1979) per night.
The atmospheric extinction was corrected by using the mean extinction
coefficients of Xinglong Station, which were measured by BATC multi-color
survey (Yan 1995).
Table 1:
Journal of observations
|
Table 2:
X-ray characteristic of the new quasars
|
Table 3:
Optical properties of the new quasars
|
![\begin{figure}
\includegraphics [height=20cm]{ds7793f1.eps}\end{figure}](/articles/aas/full/1999/02/ds7793/Timg15.gif) |
Figure 1:
Spectra of the new quasars |
The X-ray characteristics and optical properties of the 9 BLRQs are summarized
in Tables 2 and 3, and their spectra are shown in Fig. 1. Position error
radius, count rates, hardness ratios 1 & 2 listed in Table 2 are from
RASS-BSC. Hardness ratios are defined as:


where H, S, H1, and H2 are the count rates
in the hard H-band (0.4-2.4 keV), the soft S-band (0.07-0.4 keV), the hard
H1-band (0.4-1.0 keV) and the hard H2-band (1.0-2.4 keV) respectively.
The coordinates given in Table 3 were obtained from USNO-A1.0. We applied
these coordinates to the Digitized Sky Survey
and did not
find any ambiguous identifications of
the objects, so we do not
give the finding charts of the 9 BLRQs. The average
redshifts were usually determined from two or more emission lines. The B and R
magnitudes were obtained from
USNO-A1.0 and have an accuracy between 0.25
and 0.40 magnitudes depending on the declination (Monet et al. 1996).
The absolute B magnitudes were calculated by the same formula used by
Véron-Cetty & Véron (1996) under the assumption of
H0=50kms-1Mpc-1 and q0=0. The
listed in
Table 3 is the angular separation between the X-ray centroïd and the
optical countpart in arcseconds.
Acknowledgements
Special thanks to Dr. Qiu Yulei and Dr. Jiang Biwei for their hard work
of English revision of this paper. We are grateful to Miss Cao Li for her
kindly help with data reduction. We also thank Mr. Yan Haojing for providing
the extinction data of Xinglong Station. This work is partly supported by the
Pandeng Project of the Chinese Scientific Committee and the Chinese National
Natural Science Foundation.
Up: Nine newly discovered bright
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