矮星系DDO 47：检验隐藏在三轴晕中的尖点
摘要
We present HI data of the dwarf galaxy DDO 47, aimed at testing the hypothesis that dark halo triaxiality might induce non-circular motions resulting in rotation curves best fitted by cored halos, even if the dark matter halo is intrinsically cuspy. We performed a harmonic decomposition of the velocity field in order to search for alleged non-circular motions needed to ``hide'' a cusp: in DDO 47 non-circular motions are globally at a level of 2-3 km s, far from being sufficient to reconcile the observed rotation curve with the CDM predictions. We conclude that the dark matter halo around DDO 47 is truly cored and that a cusp cannot be hidden by non-circular motions. More details are shown in Gentile et al. (2006, ApJL in press, astro-ph/0506538).
引用
@article{arxiv.astro-ph/0510607,
title = {The dwarf galaxy DDO 47: testing cusps hiding in triaxial halos},
author = {G. Gentile and A. Burkert and P. Salucci and U. Klein and F. Walter},
journal= {arXiv preprint arXiv:astro-ph/0510607},
year = {2009}
}
备注
2 pages, to appear in Proc. XXIst IAP Colloquium "Mass Profiles and Shapes of Cosmological Structures", Paris 4-9 July 2005 (EAS Publications Series, G. Mamon, F. Combes, C. Deffayet, B. Fort eds.)