Effects from Dark Matter Halos on X-ray Pulsar Pulse Profiles

Abstract

Neutron stars (NSs) can capture dark matter (DM) particles because of their deep gravitational potential and high density. The accumulated DM can affect the properties of NSs. In this work we use a general relativistic two-fluid formalism to solve the structure of DM-admixed NSs (DANSs) and the surrounding spacetime. Specifically, we pay attention to the situation where those DANSs possess DM halos. Due to the gravitational effect of the DM halo, the pulse profile of an X-ray pulsar is changed. Our study finds a universal relation between the peak flux deviation of the pulse profile and $M_{\mathrm{halo}}/R_{\mathrm{BM}}$, which is the ratio of the DM halo mass, $M_{\mathrm{halo}}$, to the baryonic matter (BM) core radius, $R_{\mathrm{BM}}$. Our results show that, when $M_{\mathrm{halo}}/R_{\mathrm{BM}}=0.292$ and the DM particle mass $m_f=0.3$GeV, the maximum deviation of the profile can be larger than 100$\%$, which has implication in X-ray pulsar observation.

10 pages, 11 figures; accepted by PRD

References in corpus (21)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter
• A NICER View of PSR J0030+0451: Millisecond Pulsar Parameter Estimation
• Results from a search for dark matter in the complete LUX exposure
• WIMP Annihilation and Cooling of Neutron Stars
• Compact Stars as Dark Matter Probes
• A NICER View of the Nearest and Brightest Millisecond Pulsar: PSR J0437$\unicode{x2013}$4715
• Constraining the Neutron Star Mass-Radius Relation and Dense Matter Equation of State with NICER. II. Emission from Hot Spots on a Rapidly Rotating Neutron Star
• First star-forming structures in fuzzy cosmic filaments
• Pulse profiles of millisecond pulsars and their Fourier amplitudes
• The Oblate Schwarzschild Approximation for Light Curves of Rapidly Rotating Neutron Stars
• Gravitational effects of condensate dark matter on compact stellar objects
• Constraining scalar fields with stellar kinematics and collisional dark matter
• Thermal X-rays from Millisecond Pulsars: Constraining the Fundamental Properties of Neutron Stars
• Tides in merging neutron stars: Consistency of the GW170817 event with experimental data on finite nuclei
• Strong-field effects in massive scalar-tensor gravity for slowly spinning neutron stars and application to X-ray pulsar pulse profiles
• NICER Detection of Thermal X-ray Pulsations from the Massive Millisecond Pulsars PSR J0740+6620 and PSR J1614-2230
• Measuring the mass of the black widow PSR J1555-2908
• Neutron stars as extreme laboratories for gravity tests
• Fermionic Light Dark Matter particles and the New Physics of Neutron Stars
• Towards Uncovering Dark Matter Effects on Neutron Star Properties: A Machine Learning Approach