NGC1300 dynamics - II. The response models

Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.11). 09/2010; 408(1):9-21. DOI: 10.1111/j.1365-2966.2010.17061.x


We study the stellar response in a spectrum of potentials describing the barred spiral galaxy NGC 1300. These potentials have
been presented in a previous paper and correspond to three different assumptions as regards the geometry of the galaxy. For
each potential we consider a wide range of Ωp pattern speed values. Our goal is to discover the geometries and the Ωp supporting specific morphological features of NGC 1300. For this purpose we use the method of response models. In order to
compare the images of NGC 1300 with the density maps of our models, we define a new index which is a generalization of the
Hausdorff distance. This index helps us to find out quantitatively which cases reproduce specific features of NGC 1300 in
an objective way. Furthermore, we construct alternative models following a Schwarzschild-type technique. By this method we
vary the weights of the various energy levels, and thus the orbital contribution of each energy, in order to minimize the
differences between the response density and that deduced from the surface density of the galaxy, under certain assumptions.
We find that the models corresponding to Ωp≈ 16 and 22 km s−1 kpc−1 are able to reproduce efficiently certain morphological features of NGC 1300, with each one having its advantages and drawbacks.

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Available from: Constantinos Kalapotharakos
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