Revealing the transition from post-agb stars to planetary nebulae: non-thermal and thermal radio continuum observations
Bains, I. Cohen, M. Chapman, J. M. Deacon, R. M. Redman, M. P.
Bains, I.
Cohen, M.
Chapman, J. M.
Deacon, R. M.
Redman, M. P.
Publication Date
2009-08-11
Keywords
masers, stars: agb and post-agb, stars: late-type, stars: winds, outflows, radio continuum: stars, northern galactic plane, point-source catalog, oh maser emission, 1612 mhz survey, protoplanetary nebula, interstellar extinction, imaging polarimetry, merlin polarimetry, stellar evolution, line emission
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Article
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Citation
Bains, I. Cohen, M.; Chapman, J. M.; Deacon, R. M.; Redman, M. P. (2009). Revealing the transition from post-agb stars to planetary nebulae: non-thermal and thermal radio continuum observations. Monthly Notices of the Royal Astronomical Society 397 (3), 1386-1401
Abstract
Midcourse Space eXperiment and Infrared Astronomical Satellite colour diagnostics as well as OH maser profile characteristics were used to select a sample of post-asymptotic giant branch (pAGB) candidates for a radio continuum detection experiment with the Australia Telescope Compact Array. Seven out of 28 sources, six of which are new detections, show a continuum. A planetary nebula serendipitously detected in the field of an undetected pAGB candidate also reveals radio continuum. The radio continuum properties of these eight sources are described. Almost half have non-thermal emission. dusty modelling of the infrared spectral energy distributions (SEDs) of the three strongest detections reveals that they all have central stars with temperatures substantially lower than that required for significant photoionization, leading us to infer that the radio continuum has arisen from wind-shock interactions. This hypothesis is consistent with the detection of non-thermal radio emission in one of these three objects.
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Publisher
Oxford University Press (OUP)
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Attribution-NonCommercial-NoDerivs 3.0 Ireland