J 2025

Charged particles in dipole magnetosphere of neutron stars: epicyclic oscillations in and off-equatorial plane

VRBA, Jaroslav; Martin KOLOŠ and Zdeněk STUCHLÍK

Basic information

Original name

Charged particles in dipole magnetosphere of neutron stars: epicyclic oscillations in and off-equatorial plane

Authors

VRBA, Jaroslav; Martin KOLOŠ and Zdeněk STUCHLÍK

Edition

European Physical Journal Plus, DE - Spolková republika Německo, 2025, 2190-5444

Other information

Language

English

Type of outcome

Article in a journal

Field of Study

10308 Astronomy

Country of publisher

Germany

Confidentiality degree

is not subject to a state or trade secret

References:

URL

Impact factor

Impact factor: 2.900 in 2024

Organization unit

Institute of physics in Opava

DOI

https://doi.org/10.1140/epjp/s13360-025-06007-7

UT WoS

001411951800002

EID Scopus

2-s2.0-85217490139

Keywords in English

quasi-periodic oscillations;resonant switch model; X-ray binaries; black holes; electromagnetic fields; naked singularities;orbital resonance; energy extraction; mass contraints; magnetic fields

Tags

RIV26, UF

Tags

International impact, Reviewed

Links

GA23-07043S, research and development project.
Changed: 15/1/2026 10:58, Mgr. Pavlína Jalůvková

Abstract

In the original language

We study the motion of charged test particles around a magnetized neutron star described by the Schwarzschild gravitational field of mass M and a dipole magnetic field characterized by parameter b, representing the ratio of electromagnetic to gravitational forces. The neutron star’s radius is assumed at R=3M. Circular orbits “in” and “off” the equatorial plane, determined by the dipole field’s symmetry plane, are analyzed based on background and particle parameters; their stability against radial and latitudinal perturbations is established. The existence of chaotic charged particle motion in belts around off-equatorial orbits, influenced by sufficiently strong repulsive magnetic force, is demonstrated. The belts’ distance from the neutron star varies with parameter b for different charged particles. Frequencies of epicyclic oscillatory motion related to “in” and “off” equatorial circular orbits, alongside the orbital frequency, are determined. The magnetically modified geodesic model is applied to fit observational data from twin-peak, high-frequency quasi-periodic oscillations in binary systems containing neutron stars. Rough fitting to the data for circular orbits for particles under magnetic attraction (repulsion) is shown. The possible fittings imply strong limits on the magnetic parameter, b∼0.01 (b∼-10) for magnetic attraction (repulsion), suggesting minor influence of electromagnetic forces and test particles with small specific charges like dust or plasmoids in strong magnetic fields around neutron stars.
Displayed: 30/1/2026 08:20