Related papers: Outer gap accelerator closed by magnetic pair-crea…
The subpulse drifting phenomenon in pulsar radio emission is considered within the partially screened inner gap model, in which the sub-Goldreich-Julian thermionic flow of iron ions or electrons coexists with the spark-associated…
Recent $\gamma$-ray observations suggest that the particle acceleration occurs at the outer region of the pulsar magnetosphere. The magnetic field lines in the outer acceleration region (OAR) are connected to the neutron star surface (NSS).…
It is generally supposed that when the "compactness" $l \equiv L\sigma_T/(r m_e c^3)$ in photons above the pair-production threshold is large, few $\gamma$-rays can escape. We demonstrate that even when $l \gg 1$, if the high energy and low…
We investigate the electron-positron pair cascade taking place in the magnetosphere of a rapidly rotating black hole. Because of the spacetime frame dragging, the Goldreich-Julian charge density changes sign in the vicinity of the event…
We report the out-of-plane resistivity in the systematically oxygen-controlled single crystals Bi$_{1.74}$Pb$_{0.38}$Sr$_{1.88}$CuO$_{6+\delta}$ in magnetic fields parallel to the c-axis. Two characteristic temperatures $T^*$ and $T^{**}$…
Magnetars in quiescent states continue to emit hard X-rays with a power far exceeding the loss of rotational energy. It has recently been noted that this hard X-ray continuum may bear a direct signature of quantum electrodynamic (QED)…
Gamma-rays from pulsars can be efficiently attenuated in their magnetospheres via the mechanism of single-photon pair production and also the exotic QED process of photon splitting, which become prolific in fields approaching the quantum…
The dearth of planets with sizes around 1.8 $\mathrm{R_\oplus}$ is a key demographic feature discovered by the $Kepler$ mission. Two theories have emerged as potential explanations for this valley: photoevaporation and core-powered…
Magnetars are neutron stars characterized by strong surface magnetic fields generally exceeding the quantum critical value of 44.1 TeraGauss. High-energy photons propagating in their magnetospheres can be attenuated by QED processes like…
The accretion flow within the magnetospheric radius of bright X-ray pulsars can form an optically thick envelope, concealing the central neutron star from the distant observer. Most photons are emitted at the surface of a neutron star and…
Cross-sections for Rutherford scattering, Coulomb bremsstrahlung and pair creation, have been calculated at very high magnetic fields in order to investigate the photo-production of protons at the polar caps of pulsars whose spin is…
The cross section for muon pair productions by electrons scattering over photons, $\sigma_{MPP}$, is calculated analytically in the leading order. It is pointed out that for the center-of-mass energy range, $s \geq 5 m^{2}_{\mu}$, the cross…
Magnetic fields in extragalactic space between galaxy clusters may induce conversions between photons and axion-like particles (ALPs), thereby shielding the photons from absorption on the extragalactic background light. For TeV gamma rays,…
The importance of the photon-photon pair production process ($\gamma+ \gamma^{\prime}\to e^{+}+e^{-}$) to form pair production cascades in pulsar polar caps is investigated within the framework of the Ruderman-Sutherland vacuum gap model.…
We constrain the formation rate of Galactic magnetars directly from observations. Combining spin-down rates, magnetic activity, and association with supernova remnants, we put a 2$\sigma$ limit on their Galactic formation rate at…
At very high energies, pair production ($\gamma\to e^+e^-$) exhibits many interesting features. The momentum transfer from the target is very small, so the reaction probes the macroscopic properties of the target, rather than individual…
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…
We consider possible geometries of magnetic fields in GRB outflows, and their evolution with distance from the source. For magnetically driven outflows, with an assumed ratio of magnetic to kinetic energy density of order unity, the field…
A small percentage of normal stars harbor giant planets that orbit within a few tenths of an astronomical unit. At such distances the potential exists for significant tidal and magnetic field interaction resulting in energy dissipation that…
A two-dimensional electrodynamic model is used to study particle acceleration and non-thermal emission mechanisms in the pulsar magnetospheres. We solve distribution of the accelerating electric field with the emission process and the…