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Context: Low- and intermediate-mass stars lose most of their stellar mass atthe end of their lives on the asymptotic giant branch (AGB). Determining gasand dust mass-loss rates (MLRs) is important in quantifying the contribution ofevolved stars to the enrichment of the interstellar medium. Aims: Attempt to,for the first time, spectrally resolve CO thermal line emission in a smallsample of AGB stars in the Large Magellanic Cloud. Methods: ALMA was used toobserve 2 OH/IR stars and 4 carbon stars in the LMC in the CO J= 2-1 line.Results: We present the first measurement of expansion velocities inextragalactic carbon stars. All four C-stars are detected and wind expansionvelocities and stellar velocities are directly measured. Mass-loss rates arederived from modelling the spectral energy distribution and Spitzer/IRSspectrum with the DUSTY code. Gas-to-dust ratios are derived that make thepredicted velocities agree with the observed ones. The expansion velocities andMLRs are compared to a Galactic sample of well-studied relatively low MLRsstars supplemented with "extreme" C-stars that have properties more similar tothe LMC targets. Gas MLRs derived from a simple formula are significantlysmaller than derived from the dust modelling, indicating an order of magnitudeunderestimate of the estimated CO abundance, time-variable mass loss, or thatthe CO intensities in LMC stars are lower than predicted by the formula derivedfor Galactic objects. This could be related to a stronger interstellarradiation field in the LMC. Conclusions: Although the LMC sample is small andthe comparison to Galactic stars is non-trivial because of uncertainties intheir distances it appears that for C stars the wind expansion velocities inthe LMC are lower than in the solar neighbourhood, while the MLRs appearsimilar. This is in agreement with dynamical dust-driven wind models.

The ALMA detection of CO rotational line emission in AGB stars in the Large Magellanic Cloud