Strange stars admixed with dark matter: equiparticle model in a two fluid approach

In this work we explore the possible scenario of strange stars admixed with fermionic or bosonic dark matter.

For the description of the ``visible'' sector, we use a specific phenomenological quark model that takes into account in-medium effects for the quark masses through a suitable baryonic density dependence, in which the free parameters are chosen from the analysis of the stellar matter stability window (parametrizations presenting lower energy per baryon than iron nuclei).

In the case of the dark sector, we investigate the predictions of fermionic and bosonic models.

In the former we consider a spin $1/2$ dark particle, and the latter is described by a dark scalar meson.

Both models present a repulsive vector interaction, particularly important for the bosonic model since it helps avoiding the collapse of the star due to the lack of the degeneracy pressure.

Our results point out to possible stable strange stars configurations in agreement with data from PSR J0030+0451, PSR J0740+6620, NICER and HESS J1731-347.

As another feature, we find stars with dark matter halo configurations for lower values of the dark particle mass.

;Comment: More references added.

Some figures updated