218 citations · 2.2k across the 58 of their papers we have counts for
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On the reliability of mass-loss-rate estimates for AGB stars
Sofia Ramstedt, Fredrik L. Schoeier, Hans Olofsson +1
In the recent literature there has been some doubt as to the reliability of CO multi-transitional line observations as a mass-loss-rate estimator for AGB stars. Mass-loss rates for…
Circumstellar water vapour in M-type AGB stars: Radiative transfer models, abundances and predictions for HIFI
Matthias Maercker, Fredrik L. Schoeier, Hans Olofsson +2
Aims: By performing a detailed radiative transfer analysis, we determine fractional abundances of circumstellar H2O in the envelopes around six M-type asymptotic giant branch stars…
Embedded Stellar Populations towards Young Massive Star Formation Regions I. G305.2+0.2
S. N. Longmore, M. Maercker, S. Ramstedt +1
We present deep, wide-field J, H and Ks images taken with IRIS2 on the Anglo Australian Telescope, towards the massive star formation region G305.2+0.2. Combined with 3.6, 4.5, 5.8…
The physics and chemistry of circumstellar envelopes of S-stars on the AGB
S. Ramstedt, F. L. Schoeier, H. Olofsson
The S-stars have been suggested to be a brief transitional phase as stars evolve from oxygen-rich M-type stars into carbon stars, through the dredge up of carbon from He-shell burn…
Photospheric and chromospheric activity on EY Dra
H. Korhonen, K. Brogaard, K. Holhjem +4
Magnetic activity in the photosphere and chromosphere of the M dwarf EY Dra is studied and possible correlations between the two are investigated using photometric observations in…
Mass-loss properties of S-stars on the AGB
S. Ramstedt, F. L. Schoeier, H. Olofsson +1
We have used a detailed non-LTE radiative transfer code to model new APEX CO(J=3-2) data, and existing CO radio line data, on a sample of 40 AGB S-stars. The derived mass-loss-rate…