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We report the discovery of a giant double-lobed (lobe-core-lobe) radio-continuum structure associated with QSO J0443.8-6141 at z=0.72. This QSO was originally identified during the follow-up of a sample of ROSAT All Sky Survey sources at radio and op tical frequencies. With a linear size of ~0.77 Mpc, QSO J0443.8-6141 is classified as a giant radio source (GRS); based on its physical properties, we classify QSO J0443.8-6141 as a FR II radio galaxy. High-resolution observations are required to reliably identify GRSs; the next generation of southern-sky radio and optical surveys will be crucial to increasing our sample of these objects.
We present moderate-resolution (<5A) long-slit optical spectra of 51 nebular objects in the nearby Sculptor Group galaxy NGC 300 obtained with the 2.3 meter Advanced Technology Telescope at Siding Spring Observatory, Australia. Adopting the criterion of [SII]/Ha>=0.4 to confirm supernova remnants (SNRs) from optical spectra, we find that of 28 objects previously proposed as SNRs from optical observations, 22 meet this criterion with six showing [SII]/Ha of less than 0.4. Of 27 objects suggested as SNRs from radio data, four are associated with the 28 previously proposed SNRs. Of these four, three (included in the 22 above) meet the criterion. In all, 22 of the 51 nebular objects meet the [SII]/Ha criterion as SNRs while the nature of the remaining 29 objects remains undetermined by these observations.
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