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A catalog is presented of the IRAS observations of 85 galaxies listed in the Second Reference Catalogue of Bright Galaxies with blue-light isophotal diameters greater than 8'. "Total" flux densities at 12, 25, 60, and 100 jam, obtained from spatial maps constructed from co-added IRAS detector data, are reported. Infrared brightness profiles of the detected galaxies and infrared surface brightness contour maps of the galaxies for which structural features were resolved are displayed in an atlas. A far-infrared classification scheme based on the degree of central concentration and spatial structure of the 60 jLtm emission of the best-resolved galaxies is proposed. The 60 \im and blue-light isophotal diameters of the largest galaxies are compared.

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Abstract. We present observations of the region between −45• ≤ ≤ −10• and |b| ≤ 3 • in the OH 1612.231 MHz line, taken in 1994 January with the Australia Telescope Compact Array (ATCA)1 . These observations are part of a larger survey, covering | | ≤ 45• and |b| ≤ 3 • , with the ATCA and the Very Large Array. In a previous article we have discussed the observational strategy in detail. In this paper we present only the objects found in this part of the survey. The region was systematically searched for OH-maser emission and was covered completely with 910 pointing centres separated by 30 . We found 202 OHmasing objects, 112 of which are new detections. Out of the 202 objects, 166 have a standard double-peaked spectral profile, 32 a single-peaked profile and 4 objects have non-standard or irregular profiles. In this article we analyse the data statistically and give classifications and identifications with known sources where possible. The astrophysical, kinematical, morphological and dynamical properties of subsets of the data will be addressed in future articles 2 .

Abstract.Observations in the IJK s wave bands covering the central 20 × 20 of the Local Group galaxy NGC 6822 have been made with the William Herschel Telescope in La Palma. They have allowed us to characterize, for the first time in the near-infrared across the whole galaxy, its late-type stellar population (i.e. red giant and asymptotic giant branch stars) and to derive from the ratio between carbon-rich and oxygen-rich asymptotic giant branch stars an indication about spatial variations in metallicity. These amount to about 1.56 dex, twice of what has been previously found within each Magellanic Cloud using the same technique. We have calibrated our photometry on the DENIS (I-band) and 2MASS (J and K s bands) data and obtained a distance modulus of (m − M) 0 = 23.34 ± 0.12 from the position of the tip of the RGB. The large scale distribution of late-type stars suggests that either the galaxy is viewed under a high inclination angle or it has a non-negligible thickness.

Dust radiative transfer models are presented for 60 carbon stars in the Magellanic Clouds (MCs) for which 5-35 μm Spitzer infrared spectrograph (IRS) spectra and quasi-simultaneous ground-based JHKL photometry are available. From the modelling, the luminosity and massloss rate are derived (under the assumption of a fixed expansion velocity and dust-to-gas ratio), and the ratio of silicon carbide (SiC) to amorphous carbon (AMC) dust is also derived. This ratio is smaller than observed in Galactic carbon stars, as has been noted before. Light curves for 36 objects can be retrieved from the massive compact halo object (MACHO) and optical gravitational lensing experiment (OGLE) data bases, and periods can be derived for all but two of these. Including data from the literature, periods are available for 53 stars.There is significant scatter in a diagram where the mass-loss rates are plotted against luminosity, and this is partly due to the fact that the luminosities are derived from single-epoch data.The mass-loss rates for the MC objects roughly scatter around the mean relation for Galactic C-stars.The situation is better defined when the mass-loss rate is plotted against pulsation period. For a given period, most of the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) stars have mass-loss rates that are in agreement with that observed in Galactic carbon stars (under the assumption that these objects have an expansion velocity and dust-to-gas ratio typical of the mean observed in Galactic carbon Miras).For some SMC sources only, the IRS spectrum at longer wavelengths falls clearly below the model flux predicted by a constant mass-loss rate. An alternative model with a substantial increase of the mass-loss rate to its present-day value over a time-scale of a few tens of years is able to explain the spectral energy distribution (SED) and IRS spectra of these sources. However, the probability to have two such cases in a sample of 60 is small, and makes this not a likely explanation (and testable by re-observing these objects near the end of the lifetime of Spitzer). Alternative explanations are (ad hoc) changes to the dust emissivity at longer wavelengths, and/or deviations from spherical symmetry.