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arXiv · 1401.2562

The shape of dark matter halo in PRG NGC 4262

S. A. Khoperskov·A. V. Moiseev·A. V. Khoperskov·A. S. Saburova
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Abstract

With the aim to determine the spatial distribution of dark matter, we investigate the polar ring galaxy NGC 4262. We used the stellar kinematics data for the central galaxy obtained from optical spectroscopy together with information about the kinematics of the neutral hydrogen for polar component. It was shown that NGC 4262 is the classic polar ring galaxy case with the relative angle of $88^{\circ}$ between components. From simulations of the central galaxy and ring kinematics we found that the shape of the dark matter distribution varies strongly with the radius. Namely, the dark matter halo is flattened towards the galactic disk plane $c/a=0.4$, however it is prolate to the orthogonal (polar) plane far beyond the central galaxy $c/a=1.7$. Also, the simulations of the ring evolution let us to confirm the stability of the ring and the formation of quasi-spiral structures within it.

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S. A. Khoperskov, A. V. Moiseev, A. V. Khoperskov, A. S. Saburova. 2014-01-11. The shape of dark matter halo in PRG NGC 4262. https://arxiv.org/abs/1401.2562

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