Related papers: Probing Magnetars Using Spectral Lines with Future…
Several important mechanisms that explain the coherent pulsar radio emission rely on streaming (or beam) instabilities of the relativistic pair plasma in a pulsar magnetosphere. However, it is still not clear whether a streaming instability…
Microquasar stellar systems emit electromagnetic radiation and high-energy particles. Thanks to their location within our own galaxy, they can be observed in high detail. Still, many of their inner workings remain elusive; hence,…
Selective amplification of the line and continuum source by microlensing in a lensed quasar can lead to changes of continuum spectral slopes and line shapes in the spectra of the quasar components. Comparing the spectra of different…
Intensity mapping experiments survey the spectrum of diffuse line radiation rather than detect individual objects at high signal-to-noise. Spectral maps of unresolved atomic and molecular line radiation contain three-dimensional information…
Boasting supreme magnetic strengths, magnetars are among the prime candidates to generate fast radio bursts. Several theories have been proposed for the formation mechanism of magnetars, but have not yet been fully tested. As different…
Radio pulsars are believed to have their emission powered by the loss of rotational kinetic energy. By contrast, magnetars show intense X-ray and gamma-ray radiation whose luminosity greatly exceeds that due to spin-down and is believed to…
We study the pulse morphologies and pulse amplitudes of thermally emitting neutron stars with ultrastrong magnetic fields. The beaming of the radiation emerging from a magnetar was recently shown to be predominantly non-radial, with a small…
Recent observations indicate that magnetars may commonly reside in merging compact binaries and at least part of fast radio bursts (FRBs) are sourced by magnetar activities. It is natural to speculate that a class of merging neutron star…
We analyze a sample of\textit{ Swift} gamma-ray bursts (GRBs) with extended emissions in $\gamma$-rays and/or X-ray plateaus that may be driven by magnetars. Multi-wavelength data and multi-standards have been adopted to investigate the…
Thermal surface radiation has been detected with X-ray instruments for several neutron stars with high spectral, spatial and timing resolution. These observations allow for direct study of fundamental properties of the source, but require…
BeppoSAX observed several galactic binary X-ray pulsars during the Science Verification Phase and in the first year of the regular program. The complex emission spectra of these sources are an ideal target for the BeppoSAX instrumentation,…
Accreting X-ray pulsars are among the most luminous objects in the X-ray sky. In highly magnetized neutron stars (B~10^12 G), the flow of matter is dominated by the strong magnetic field. The general properties of accreting X-ray binaries…
In theory, burst activity of the magnetar can lead to the formation of fireballs trapped by the magnetic field and corotating with the star. However, the smoking-gun observational evidence of the fireball is elusive. We envisage that the…
X-ray emission from cool stars is an important tracer for stellar activity. The X-ray luminosity reflects different levels of activity and covers four orders of magnitude in stars of spectral types M-F. Low spectral resolution provided by…
We investigate the gamma-ray spectrum in the MeV range arising from electron-positron pair annihilation in fireballs associated with magnetar giant flares (MGFs), motivated by the recent observation of a MeV gamma-ray line feature in a…
A model of fast radio bursts, which enlists young, short period extragalactic magnetars satisfying $B/P > 2 \times 10^{16}$~G~s$^{-1}$ (1~G = 1~statvolt~cm$^{-1}$) as the source, is proposed. When the parallel component $\bE_\parallel$ of…
Radio spectroscopy offers a number of tools for studying a large variety of astrophysical phenomena, ranging from stars and their environment to interstellar and intergalactic medium, active galactic nuclei (AGN) and distant quasars. Main…
We study the multiwavelength properties of an optically selected sample of Low Ionization Nuclear Emission-line Regions (LINERs), in an attempt to determine the accretion mechanism powering their central engine. We show how their X-ray…
The last decade has seen the rapid, concurrent development of new classes of energetic astrophysical transients, including Fast Radio Bursts, Superluminous Supernovae, and ultralong gamma-ray bursts. We consider the implications of an…
We explore the hardness-intensity correlations observed in several AXPs and SGRs within the framework of a thermally emitting magnetar model. Using our detailed atmosphere models and taking into account reprocessing of the surface emission…