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We have carried out a radio-wavelength imaging survey of 45 bright-rimmedclouds (BRCs), using the Australia Telescope Compact Array to characterise thephysical properties in their ionised boundary layers. We detected radioemission from a total of 25 clouds and using a combination of Digitised SkySurvey and mid-infrared MSX micron images classified the emission into thatassociated with the ionised cloud rims, that associated with embedded possiblemassive YSOs and that unlikely to be associated with the clouds at all. A totalof 18 clouds display radio emission clearly associated with the cloud rim andwe determine the ionising photon flux illuminating these clouds and theelectron density and pressure of their ionised boundary layers. Using a globalestimate for the interior molecular pressure of these clouds we show that themajority are likely to be in pressure equilibrium and hence are currently beingshocked by photoionisation-induced shocks. We identify those clouds where thepredicted ionising photon flux is inconsistent with that derived from theobservations and show that either the spectral types of the stars illuminatingthe BRCs are earlier than previously thought or that there must be additionalionising sources within the HII regions. Finally, we identify the radio sourcesembedded within the clouds with infrared stellar clusters and show that theycontain late O and early B-type stars, demonstrating that a number of BRCs areintimately involved with high to intermediate-mass star formation.Comment: Accepted by A&A. 17 pages. NB: figures presented here are  low-resolution postscript images. Full resolution images are available from  the lead author upon reques

A Compact Array imaging survey of southern bright-rimmed clouds