出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We present the HI data for 5 spiral galaxies that, along with their Ha rotation curves, are used
in Gentile et al. (2004, MNRAS, 351, 903) to derive the distribution of dark matter within these
objects. The HI rotation curves obtained are derived by constructing model data cubes that are
iteratively compared to the observed ones. The HI rotation curves agree well with the Ha data,
where they coexist. Moreover, the combined Ha + HI rotation curves are smooth, symmetric and
extended to large radii.
The rotation curves are decomposed into stellar, gaseous and dark matter contributions and the
inferred density distribution is compared to various mass distributions: dark haloes with a central
density core, L Cold Dark Matter (LCDM) haloes (NFW, Moore profiles), HI scaling and
MOND. The observations point to haloes with constant density cores of size rcore ropt . LCDM
models are in clear conflict with the data. HI scaling and MOND cannot account for the observed
kinematics: we find some counter-examples.
We also present some projects aimed at making steps forward in unveiling the properties of dark
matter, in particular its outer density distribution.
