arXiv subjects

Mariana Lira

Publications and source records attributed to Mariana Lira.

3 recordsLinked to original sources

arXiv2024

On the detectability of gravitational waves emitted from head-on collisions of $\ell$-boson stars

In this work, we investigate head-on collisions of $\ell$-boson stars, potential candidates for dark matter compact objects. We begin with a review of the general properties and features of these stars, leveraging results from prior studies to analyze the gravitational wave signals generated by such collisions. Considering a maximum distance of 100 Mpc for potential events, we identify the range of masses and scalar field frequencies for these stars that would render the gravitational waves detectable by current gravitational wave observatories. Additionally, we process the resulting signals to generate simulated observatory images, highlighting their similarities and differences compared to those produced by black hole collisions.

gr-qc↗

arXiv2023

Electric traversable wormhole supported by a charged scalar field

Solving the Einstein-Klein-Gordon-Maxwell system, we construct and analyze the properties of an electrically charged wormhole, formed from a complex, massive scalar field, with self-interaction, and endowed with an electric charge. The scalar field is minimally coupled to the gravitational and the Maxwell field. Covering regions of the value of the different parameters of such wormhole, we present the dependence of the form of the solution with respect to the value of the different parameters, emphasising the role played by the charge in the configurations; we focus on the region for large values of the self-interaction parameter and found a generic behavior of the scalar field, which in turn allows us to determine explicit analytic expressions for the fields, the metric function and the global quantities such as the Komar mass and the particle number. The motion of charges in these spacetimes is also reported.

gr-qc↗

arXiv2022

On the role of magnetic fields into the dynamics and gravitational wave emission of binary neutron stars

Modelling as a dipole the magnetic interaction of a binary system of neutron stars, we are able to include the magnetic effects in the Newtonian and in the inspiral dynamics of the system using an equivalent one-body description. Furthermore, in the inspiral stage we determine the role of the magnetic interaction in the waveforms generated by the system and obtain explicit formulas for the decrease in the separation of the stars, the time to reach a minimal radius, the gravitational luminosity and the change of gravitational wave frequency, all this within the quadrupole approximation. For the magnitude of the magnetic field that is consider to exist in these binaries $\sim 10^{16} {\rm G}$ we are able to show that its effect on the observable quantities is of the order of the 2PN correction, already close to the detection range of the gravitational waves observatories. %} We also discuss cases in which the magnetic field could have a more significant influence.

gr-qc↗