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arXiv · 0810.3404

Dynamical modelling of the elliptical galaxy NGC 2974

Zhenglu Jiang
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Abstract

In this paper we analyse the relations between a previously described oblate Jaffe model for an ellipsoidal galaxy and the observed quantities for NGC 2974, and obtain the length and velocity scales for a relevant elliptical galaxy model. We then derive the finite total mass of the model from these scales, and finally find a good fit of an isotropic oblate Jaffe model by using the Gauss-Hermite fit parameters and the observed ellipticity of the galaxy NGC 2974. The model is also used to predict the total luminous mass of NGC 2974, assuming that the influence of dark matter in this galaxy on the image, ellipticity and Gauss-Hermite fit parameters of this galaxy is negligible within the central region, of radius $0.5R_{\rm e}.$

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Zhenglu Jiang. 2008-10-19. Dynamical modelling of the elliptical galaxy NGC 2974. https://doi.org/10.1007/s10569-008-9164-3

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