Author(s)

Gianluca Castignani, Noemi Frusciante, Daniele Vernieri, Paolo Salucci

INFN, Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Trieste, Italy.
NFN, Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Trieste, Italy;.
SISSA-ISAS, International School for Advanced Studies.
SISSA-ISAS, International School for Advanced Studies, Trieste, Italy;.

In spiral galaxies, we explain their non-Keplerian rotation curves (RCs) by means of a non-luminous component embedding their stellar-gaseous disks. Understanding the detailed properties of this component (labelled Dark Matter, DM) is one of the most pressing issues of Cosmology. We investigate the recent relationship (claimed by Walker et al. 2010, hereafter W + 10) between r, the galaxy radial coordinate, and V_h(r), the dark halo contribution to the circular velocity at r, 1) in the framework of the Universal Rotation Curve (URC) paradigm and directly 2) by means of the kinematics of a large sample of DM dominated spirals. We find a general agreement between the W + 10 claim, the distribution of DM emerging from the URC and that inferred in the (low luminosity) objects of our sample. We show that such a phenomenology, linking the spiral’s luminosity, radii and circular velocities, implies an evident inconsistency with (naive) predictions in the Λ Cold Dark Matter (ΛCDM) scenario.

Galaxies; Spiral; Kinematics and Dynamics; Dark Matter

Castignani, G. , Frusciante, N. , Vernieri, D. and Salucci, P. (2012) The density profiles of dark matter halos in spiral galaxies. Natural Science, 4, 265-270. doi: 10.4236/ns.2012.45038.