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We have undertaken a spectral-line imaging survey of a arcmin area around Sagittarius (Sgr) B2 near the centre of the Galaxy, in the range from 30 to 50 GHz, using the Mopra telescope. The spatial resolution varies from 1.0 to 1.4 arcmin and the spectral resolution varies from 1.6 to 2.7 km s over the frequency range. We present velocity-integrated emission images for 47 lines: 38 molecular lines and nine radio recombination lines. There are significant differences between the distributions of different molecules, in part due to spatial differences in chemical abundance across the complex. For example, HNCO and HOCO are found preferentially in the north cloud, and CHNH near Sgr B2 (N). Some of the differences between lines are due to excitation differences, as shown by the 36.17- and 44.07-GHz lines of CHOH, which have maser emission, compared to the 48.37-GHz line of CHOH. Other major differences in integrated molecular line distribution are due to absorption of the 7-mm free-free continuum emission (spatially traced by the radio recombination line emission) by cool intervening molecular material, causing a central dip in the molecular line distributions. These line distribution similarities and differences have been statistically described by Principal Component Analysis and interpreted in terms of simple Sgr B2 physical components of the cooler, lower density envelope, and dense, hot cores Sgr B2 (N), (M) and (S). [ABSTRACT FROM AUTHOR]

We present and discuss a new catalogue of 48 compact H II regions in the Small Magellanic Cloud (SMC) and a newly created deep 1420 MHz (λ=20 cm) radio-continuum image of the N19 region located in the southwestern part of the SMC. The new images were created by merging 1420 MHz radio-continuum archival data from the Australian Telescope Compact Array. The majority of these detected radio compact H II regions have rather flat spectral indices which indicates, as expected, that the dominant emission mechanism is of thermal nature. [ABSTRACT FROM AUTHOR]

We present a series of new high-sensitivity and high-resolution radio-continuum images of M31 at λ=20 cm (v=1.4 GHz). These new images were produced by merging archived 20 cm radio-continuum observations from the Very Large Array (VLA) telescope. Images presented here are sensitive to rms=60 µJy and feature high angular resolution (<10") . A complete sample of discrete radio sources have been catalogued and analysed across 17 individual VLA projects. We identified a total of 864 unique discrete radio sources across the field of M31. One of the most prominent regions in M31 is the ring feature for which we estimated total integrated flux of 706 mJy at λ=20 cm. We compare here detected sources to those listed in Gelfand et al. (2004) at λ=92 cm and find 118 sources in common to both surveys. The majority (61%) of these sources exhibit a spectral index of a<-0.6 indicating that their emission is predominantly non-thermal in nature, that is more typical for background objects. [ABSTRACT FROM AUTHOR]

We present two new catalogues of radio-continuum sources in the field of the Small Magellanic Cloud (SMC). These catalogues contain sources found at 4800 MHz (λ=6 cm) and 8640 MHz (λ=3 cm). Some 457 sources have been detected at 3 cm with 601 sources at 6 cm created from new high-sensitivity and resolution radio-continuum images of the SMC from Crawford et al. (2011). [ABSTRACT FROM AUTHOR]