Related papers: The influence of magnetic field geometry on magnet…
In the framework of the magnetar model for the Soft Gamma Repeaters and Anomalous X-ray Pulsars, we consider the structure of neutron star magnetospheres threaded by large-scale electrical currents. We construct self-similar, force-free…
The X-ray spectra observed in the persistent emission of magnetars are evidence for the existence of a magnetosphere. The high-energy part of the spectra is explained by resonant cyclotron upscattering of soft thermal photons in a twisted…
The anomalous X-ray pulsars and soft gamma-repeaters are peculiar high-energy sources believed to host a magnetar, i.e. an ultra-magnetized neutron star. Their persistent, soft X-ray emission (~1-10 keV)is usually modeled by the…
We study the effect of the magnetic field geometry on the oscillation spectra of strongly magnetized stars. The magnetic field distributions include both toroidal and poloidal contributions. We observe that the toroidal contribution does…
Magnetars are a subclass of neutron stars with ultra-strong surface magnetic fields. Some magnetars exhibit persistent hard X-ray emission, characterized by power-law tails with photon indices around 1--1.5, extending from ${\sim}$10 keV to…
(ABBREVIATED) We consider the structure of neutron star magnetospheres threaded by large-scale electrical currents, and the effect of resonant Compton scattering by the charge carriers (both electrons and ions) on the emergent X-ray spectra…
Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs) are recognized as the most promising magnetar candidates, as indicated by their energetic bursts and rapid spin-downs. It is expected that the strong magnetic field leaves…
Compton scattering is a key process shaping spectra formation and accretion flow dynamics in accreting strongly magnetized neutron stars. A strong magnetic field affects the scattering cross section and makes it dependent on photon energy,…
The presence of strong magnetic fields in neutron stars, such as in magnetars, may significantly affect their crust-core transition properties and the crust size. This knowledge is crucial in the correct interpretation of astrophysical…
This work aims at studying how magnetic fields affect the observational properties and the long-term evolution of isolated neutron stars, which are the strongest magnets in the universe. The extreme physical conditions met inside these…
We present the first self-consistent theoretical models of magnetar spectra that take into account the combined effects of the stellar atmosphere and its magnetosphere. We find that the proton cyclotron lines that are already weakened by…
In the magnetar model, the quiescent non-thermal soft X-ray emission from Anomalous X-ray Pulsars and Soft-Gamma Repeaters is thought to arise from resonant comptonization of thermal photons by charges moving in a twisted magnetosphere.…
It has been clear for some time now that super-critical surface magnetic fields, exceeding 4 x 10^13 G, exist on a subset of neutron stars. These magnetars may harbor interior fields many orders of magnitude larger, potentially reaching…
The association of all three soft gamma-ray repeaters (SGRs) with supernova remnants has made possible estimates of the distance to and luminosity of the sources of SGRs, which have provided a starting point for detailed modeling. One of…
The study of magnetars is of particular relevance since these objects are the only laboratories where the physics in ultra-strong magnetic fields can be directly tested. Until now, spectroscopic and timing measurements at X-ray energies in…
Soft X-ray emission from neutron stars affords powerful diagnostic tools for uncovering their surface and interior properties, as well as their geometric configurations. In the atmospheres of neutron stars, the presence of magnetic fields…
Large-scale magnetic fields affect the scalar modes of the geometry whose ultimate effect is to determine the anisotropies of the Cosmic Microwave Background (CMB in what follows). For the first time, a consistent numerical approach to the…
There is an increasing theoretical and observational evidence that the external magnetic field of magnetars may contain a toroidal component, likely of the same order of the poloidal one. Such "twisted magnetospheres" are threaded by…
Magnetic fields play a fundamental role for interior and atmospheric properties of M dwarfs and greatly influence terrestrial planets orbiting in the habitable zones of these low-mass stars. Determination of the strength and topology of…
With increasing patient and staff X-ray radiation awareness, many efforts have been made to develop accurate patient dose estimation methods. To date, Monte Carlo (MC) simulations are considered golden standard to simulate the interaction…