Spectroscopy Follow-up

Using the 74-inch (188 cm) telescope at Mount Stromlo Observatory, we obtained spectra for the 97 new H objects detected in our 1.0m telescope imaging survey. We have also re-measured radial velocities for a subset of 317 PNe from the Acker et al. (1992) Catalogue. in the more extended region l = and b = and : this larger sample is also being used for some dynamical comparisons, although the discovery process for this larger sample is much less homogeneous.

We used the Boller and Chivens spectrograph with the 600 l mm grating blazed at 7500 Å  in first order and the GEC 385 x 578 UV coated CCD. The spectrograph slit width was 2 arcsec. This CCD has a pixel size of and a readout noise of 10. We binned the CCD with a factor 3 along the slit and a factor 1 in . The grating was set to have a wavelength coverage from 6200 Å to 6800 Å . A GG 475 filter in the beam was used to cut off light from the second order blue. This setup gave a wavelength scale of about 1 Å  pixel (50 km ). Table 1 summarizes the final count of our 97 new candidates.

There were 193 catalogue PNe with published radial velocities. Figure 2 show a comparison of our velocity values against the catalogued velocities. Apart from a few outliers, we find good agreement with the catalogued values. Our measurement error is 11 km .

© Copyright Astronomical Society of Australia 1997