Description
Galaxy rotation curves imply there is unaccounted mass in galaxies, attributed to dark matter. However, constraining the amount of dark matter in galaxies is challenging due to the disc-halo degeneracy. Stellar bars introduce non-axisymmetries in the potentials of galaxies, which imprint distinctive signatures in the gas morphology, that enable us to break the disc-halo degeneracy. By modelling the gas response of potentials extracted for nearby galaxies from the PHANGS survey, I aim to to break the disc-halo degeneracy, and shed light on the amount of dark matter in these galaxies. I am starting by checking the method assumptions that go into the gas-response modelling, and test its validity. In particular, I am using an N-body+hydrodynamic RAMSES simulations to find out whether dark matter also forms a bar, or whether all the non-axisymmetries in the potentials of massive spirals originate form the stellar component. This work will help to break the disc-halo degeneracy in massive spiral galaxies, and shed light in the amount of dark matter in their inner regions.
