Ciencias Naturales

Dark Matter Inferences from Rotation Curve Fitting

by Juan Carlos Basto-Pineda (Universidad de Sao Paulo Brasil)

America/Bogota
Auditorio 402 Esc Fisica UIS ()

Auditorio 402 Esc Fisica UIS

Description
Rotation curves of disk galaxies are often used to probe the gravitational potential of their hosting dark matter (DM) haloes. Combining kinematic and photometric data several authors argue that the density profile of galactic halos is nearly flat in the central region (rho_ρinner proportional to r^0 ). This fact is in contradiction with the steep profile expected from cosmological cold dark matter simulations (rho_ρinner proportional tor^(−1) ), challenging both observers and theoreticians (so called the core/cusp problem). It is worth nothing however that inherent uncertainties exist in both approaches, preventing a definite verdict on this problem thus far. In this work we attempt to bring the analysis of observations and cosmological simulations closer together. For this we apply the full observers’ pipeline on a large set of mock data from simulated disk galaxies and compare the results to the real DM density profiles as directly measured from the snapshots. The agreement is quantified in terms of several critical parameters such as inclination or the amount of non-axysimmetric features in the light/velocity distributions. Our grid of simulations span a range in galaxy sizes and masses reproducing several realistic features. The mock catalog includes multiband photometry from several instruments plus realistic HI data cubes and velo- city maps. Our approach thus provides an accurate assessment of potential systematic uncertainties in the interpretation of the observational data.