Gravitational Lensing with Scalar Field Dark Matter
Cosmology Beyond the Standard Model
Antonio Herrera Martin
Prof. Martin Hendry(University of Glasgow), Dr. Luis Urena(Universidad de Guanajuato)
University of Glasgow
For several decades the study of dark matter halo profiles has been an important topic in cosmology. Despite the great success of CDM in explaining a wide variety of cosmological observations, across a broad range of physical scales, there are several significant puzzles and discrepancies that remain to be resolved – perhaps most notably the apparent conflict between the CDM prediction of cuspy-cored halo profiles and direct observations of dwarf galaxies.
Recently Schive et al. have carried out numerical simulations of large scale structure in which the dark matter is described by a self-gravitating bosonic field, which they have shown to produce a density profile that is well described by a solitonic core and a Navarro, Frenk and White (NFW) profile for the tail. This profile is significantly less cuspy than a pure NFW profile and, therefore, could potentially address some of the unsolved problems with standard CDM. In this poster we consider the strong lensing signatures of the Schive et al. density profile. We derive analytic expressions for its surface mass density and present a useful parametrisation of the lens equation, which is also analytic in the special case where the solitonic core provides the dominant contribution to the profile. We thus compare the Einstein radius and other lensing properties for the Schive et al profile with these quantities derived for other well-studied dark matter profiles – i.e. NFW, Burkert and the self-interacting scalar field model of González-Morales et al.
16:30 - 18:00