Related papers: Is Coherence Essential to Account for Pulsar Radio…
Radio observations from normal pulsars indicate that the coherent radio emission is excited by curvature radiation from charge bunches. In this review we provide a systematic description of the various observational constraints on the radio…
We discuss physical constrains that observations of high brightness temperature coherent radio emission, with brightness temperatures as high as $T_b \sim 10^{35}$ K, impose on the plasma parameters at relativistically moving astrophysical…
Searching for the physical mechanism that can excite the coherent radio emission in pulsars is still an enigmatic problem. A wealth of high quality observations exist, which over the years have been instrumental in putting stringent…
High brightness temperature radio transients such as pulsars and fast radio bursts require the coherent radiation of particles. The antenna class of coherent radiation models require a large number of charged particles radiating in phase,…
We consider the widespread hypothesis that coherent curvature radiation is responsible for the radio emission of pulsars. The comparison of energy conservation and the published data and luminosities explicitely proves that coherent…
The pulsar radio emission originates from regions below 10% of the light cylinder radius. This requires a mechanism where coherent emission is excited in relativistic pair plasma with frequency $\nu_{cr}$ which is below the plasma frequency…
Synchrotron emission of relativistic particles in magnetic fields is a process of paramount importance in astrophysics. Although known for over thirty years, there are still aspects of this radiative process that have received little…
We review a physical model where the high brightness temperature of 10$^{25}-10^{30}$ K observed in pulsar radio emission is explained by coherent curvature radiation excited in the relativistic electron-positron plasma in the pulsar…
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…
The fast (ms) radio bursts reported by Thornton, {\it et al.} have extremely high brightness temperatures if at the inferred cosmological distances. This implies coherent emission by "bunches" of charges. We model the emission region as a…
The extremely high brightness temperatures of pulsars and fast radio bursts (FRBs) require their radiation mechanisms to be coherent. Coherent curvature radiation by bunches has been long discussed as the mechanism for radio pulsars and…
We calculate the beaming of coherent emission by means of geometrical optics. When spherical elementary waves are phase-coupled in that way that constructive interference occurs along one axis, the intensity is lower for off-axis viewing…
Both induced Compton scattering and induced Raman scattering strongly limit the observability of the extremely bright (<< 10^21K), prompt coherent radio emission recently predicted to emanate from gamma-ray bursts. Induced Compton…
Observations have established that coherent radio emission from pulsars arise at few hundred kilometers above stellar surface. Recent polarization studies have further demonstrated that plasma instabilities are necessary for charge bunching…
Forty years have passed since the discovery of pulsars, yet the physical mechanism of their coherent radio emission is a mystery. Recent observational and theoretical studies strongly suggest that the radiation outcoming from the pulsar…
Recent observations of the Crab pulsar show no evidence for a spectral break in the infrared regime. It is argued that the observations are consistent with a power-law spectrum in the whole observable infrared - optical range. This is taken…
Fast radio bursts are extragalactic radio transient events lasting a few milliseconds with a ~Jy flux at ~1 GHz. We propose that these properties suggest a neutron star progenitor, and focus on coherent curvature radiation as the radiation…
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…
Extended Air Showers produced by cosmic rays impinging on the earth atmosphere irradiate radio frequency radiation through different mechanisms. Upon certain conditions, the emission has a coherent nature, with the consequence that the…
In their catalogue of pulsars' radio spectra, Swainston et al. (2022, PASA, 39, e056) distinguish between five different forms of these spectra: those that can be fitted with (i) a simple power law, (ii) a broken power law, (iii) a…