Samenvatting
We present a new H I modelling tool called GALACTUS. The program has
been designed to perform automated fits of disc-galaxy models to
observations. It includes a treatment for the self-absorption of gas.
The software has been released into the public domain. We describe the
design philosophy and inner workings of the program. After this, we
model the face-on galaxy NGC 2403 using both self-absorption and
optically thin models, showing that self-absorption occurs even in
face-on galaxies. These results are then used to model an edge-on
galaxy. It is shown that the maximum surface brightness plateaus seen in
Paper I of this series are indeed signs of self-absorption. The apparent
H I mass of an edge-on galaxy can be drastically lower compared with
that same galaxy seen face-on. The Tully-Fisher relation is found to be
relatively free from self-absorption issues.
Originele taal-2 | English |
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Pagina's (van-tot) | 21-31 |
Aantal pagina's | 11 |
Tijdschrift | Monthly Notices of the Royal Astronomical Society |
Volume | 464 |
Nummer van het tijdschrift | 1 |
DOI's | |
Status | Published - jan.-2017 |