5–10 Sept 2021
Online
Europe/Lisbon timezone

Constraints on the fermionic dark matter from observations of neutron stars

8 Sept 2021, 16:00
15m
Online

Online

Talk Nuclear and particle astrophysics Nuclear and particle astrophysics

Speaker

Violetta Sagun (University of Coimbra)

Description

We study an impact of asymmetric dark matter on properties of neutron stars and their ability to reach the two solar masses limit, which allows us to present a new range of masses of dark matter particles and their fractions inside the star. Our analysis is based on the observational fact of the existence of two pulsars reaching this limit and on the theoretically predicted reduction of the neutron star maximal mass caused by the accumulation of dark matter in its interior. We also demonstrate that light dark matter particles with masses below 0.2 GeV can create an extended halo around the neutron star leading not to decrease, but to increase of its visible gravitational mass. By using recent results on the spatial distribution of dark matter in the Milky Way, we present an estimate of its fraction inside the neutron stars located in the Galaxy center. We show how the detection of a 2 Msun neutron star in the most central region of the Galaxy will impose an upper constraint on the mass of dark matter particles of ∼60 GeV. Future high precision measurements of the neutron stars maximal mass near the Galactic center, will put a more stringent constraint on the mass of the dark matter particle. This last result is particularly important to prepare ongoing, and future radio and x-ray surveys.

Primary authors

Violetta Sagun (University of Coimbra) Oleksii Ivanytskyi (University of Wroclaw) Ilidio Lopes (CENTRA, Instituto Superior Técnico)

Presentation materials