Related papers: Polar-cap accelerator and radio emission from puls…
We consider the voltage structure in the open-field circuit and outer magnetosphere of a magnetar. The standard polar-cap model for radio pulsars is modified significantly when the polar magnetic field exceeds 1.8x10^{14} G. Pairs are…
Analysis of plasma acceleration in pulsars with positive corotational charge density has shown that any element of area on the polar cap is bi-stable: it can be in phases either of pure proton emission or of mixed ions and protons (the ion…
We consider the polarization behaviour of radio waves propagating through an ultrarelativistic highly magnetized electron-positron plasma in a pulsar magnetosphere. The rotation of magnetosphere gives rise to the wave mode coupling in the…
Similar to the terrestrial collision accelerators of electron-antielectron, another kind of accelerator is above a positively or negatively charged pulsar polar cap. In the case of pulsars with magnetic axis parallel (anti-parallel) to…
I argue that the problem of electromagnetically driven electron-positron cascades in magnetospheres of neutron stars must be addressed starting from first principles. I describe a general numerical algorithm for doing self-consistent…
The study of physical processes associated with particle acceleration in the open field line region above the polar cap (PC) of an isolated neutron star (NS) plays a fundamental role in our understanding and interpretation of high-energy…
(shortened) We report the results of an investigation of particle acceleration and electron-positron plasma generation at low altitude in the polar magnetic flux tubes of Rotation Powered Pulsars, when the stellar surface is free to emit…
We have programmed a full simulation of the open field lines above the polar cap of a magnetized pulsar, using time dependent Particle In Cell (PIC) numerical code (Birdsall and Langdon 1991). We consider the case of free ejection of…
Thermal radiation from hot polar caps is examined in radio pulsars with drifting subpulses. It is argued that if these subpulses correspond to sparking discharges of the inner acceleration region right above the polar cap surface then a…
Pulsar radio emission is believed to be originated from the electron-positron pairs streaming out from the polar cap region. Pair formation, an essential condition for pulsar radio emission, is believed to be sustained in active pulsars via…
Current closure in the pulsar magnetosphere holds the key to its structure. We must determine not only the global electric circuit, but also the source of its electric charge carriers. We address this issue with the minimum number of…
Several classes of neutron star are sources of coherent emission at frequencies of 10^2 - 10^3 MHz: others are radio-quiet. The primary emission spectra are broadly universal in form over many orders of magnitude in rotation period and…
The magnetic field of magnetars may be twisted compared with that of normal pulsars. Previous works mainly discussed magnetic energy release in the closed field line regions of magnetars. For a twisted magnetic field, the field lines will…
The influence of surface small scale magnetic field on the heating of PSR J0250+5854 polar cap is considered. It is assumed that polar cap is heated only by reverse positrons, accelerated in pulsar diode. It is supposed that pulsar diode is…
It is shown that the time-variability inherent in the ion-proton polar cap leads naturally to growth of Langmuir modes on narrow bundles of magnetic flux lines and that the observed size of micropulses is consistent with the smallest such…
If the binding energy of the pulsar's surface is not so high (the case of a neutron star), both the negative and positive charges will flow out freely from the surface of the star. The annular free flow model for $\gamma$-ray emission of…
We discuss the creation of electron-positron cascades in the context of pulsar polar cap acceleration models and derive several useful analytic and semi-analytic results for the spatial extent and energy response of the cascade. Instead of…
We suggest a mechanism for generation of radio emission from polars. It is based on the cyclotron radiation of thermal electrons at the background of fluctuating magnetic field. The source of fluctuations is Alfv\'{e}n wave turbulence.…
It is shown that for moderately hot polar caps (with effective temperature of $\sim 10^6$ K), the efficiency of polar gap acceleration is lower compared to the case in which the polar caps are relatively cool and inverse Compton scattering…
Using an analytic, axisymmetric approach that includes general relativity, coupled to a condition for pair production deduced from simulations, we derive general results about the spatial distribution of pair-producing field lines over the…