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The linear relationship between pulsar micro-pulse widths and rotation period is consistent with the existence of a physical length L on the neutron-star surface and seen on the observer arc of transit across the polar cap. Within the…

High Energy Astrophysical Phenomena · Physics 2024-05-15 P B Jones

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…

High Energy Astrophysical Phenomena · Physics 2015-06-24 P. B. Jones

Ions, protons and possibly a small flux of electrons and positrons are accelerated outward from the polar cap of a normal or millisecond pulsar whose rotational spin is antiparallel with its magnetic moment. The Langmuir modes of this…

High Energy Astrophysical Phenomena · Physics 2015-06-22 P. B. Jones

Evidence derived with minimal assumptions from existing published observations is presented to show that an ion-proton plasma is the source of radio-frequency emission in millisecond and in normal isolated pulsars. There is no primary…

High Energy Astrophysical Phenomena · Physics 2016-04-27 P B Jones

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…

High Energy Astrophysical Phenomena · Physics 2017-05-10 P B Jones

Radio luminosities have been estimated from published data for a well-defined homogeneous set of 29 normal pulsars. The radio-frequency energies per unit charge in the primary accelerated particle beam are given for each pulsar and form a…

High Energy Astrophysical Phenomena · Physics 2015-06-22 P. B. Jones

We have developed a method to compute the possible distribution of radio emission regions in a typical pulsar magnetosphere, taking into account the viewing geometry and rotational effects of the neutron star. Our method can estimate the…

Astrophysics of Galaxies · Physics 2015-05-18 R. M. C. Thomas , Y. Gupta , R. T. Gangadhara

We have examined the cyclotron resonance instability developing in the relativistic out-flowing plasma in the pulsar magnetosphere. The instability condition leads to radio emission in the sub-GHz frequency regime which is likely to be seen…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Rahul Basu , Dipanjan Mitra , George I. Melikidze

Recent multi-frequency measurements of pulse widths W50 for the long-period pulsar J0250+5854 by Agar et al provide a unique insight to the emission process owing to its small polar-cap radius. The frequency-dependence of W50 can be simply…

High Energy Astrophysical Phenomena · Physics 2021-12-15 P B Jones

Super-sensitive observations of bright pulsars by the Five-hundred-meter Aperture Spherical radio Telescope (FAST) have revealed weak radio emission continuously emerged in the rotation phases between the main pulse and interpulse of an…

High Energy Astrophysical Phenomena · Physics 2025-04-10 P. F. Wang , J. L. Han

It is shown that pulsar radio emission can be generated effectively through a streaming motion in the polar-cap regions of a pulsar magnetosphere causing nonresonant growth of waves that can escape directly. As in other beam models, a…

Astrophysics · Physics 2009-11-07 M. Gedalin , E. Gruman , D. B. Melrose

Aberration and retardation of the radiation within a pulsar's magnetosphere enable a single corotating absorbing region in the outer magnetosphere to give rise to a 'double notch' in the pulsar's observed radio profile. This effect requires…

Astrophysics · Physics 2009-11-10 Geoffrey A. E. Wright

In Basu et al. 2011 we reported the detection of Off-pulse emission from two long period pulsars B0525+21 and B2045-16. The pulsars were observed at a single epoch using the 325 MHz frequency band of the Giant Meterwave Radio Telescope…

Astrophysics of Galaxies · Physics 2012-10-04 Rahul Basu , Dipanjan Mitra , Ramana Athreya

In the standard picture of radio pulsars, the radio emission arises from a set of open magnetic field lines, the extent of which is primarily determined by the pulsar's spin period, P, and the emission height. We have used a database of…

High Energy Astrophysical Phenomena · Physics 2019-02-20 Simon Johnston , Aris Karastergiou

Since pulsars were discovered as emitters of bright coherent radio emission more than half a century ago, the cause of the emission has remained a mystery. In this Letter we demonstrate that coherent radiation can be directly generated in…

High Energy Astrophysical Phenomena · Physics 2020-06-29 Alexander Philippov , Andrey Timokhin , Anatoly Spitkovsky

Motivated by recent results on the location of the radio emission in pulsar magnetospheres, we have developed a model which can account for the large diversity found in the average profile shapes of pulsars. At the centre of our model lies…

Astrophysics · Physics 2009-11-13 A. Karastergiou , S. Johnston

Observations suggest that in normal period radio pulsars, coherent curvature radiation is excited within 10$\%$ of the light cylinder. The coherence is attributed to Langmuir mode instability in a relativistically streaming one-dimensional…

High Energy Astrophysical Phenomena · Physics 2022-08-15 Sk. Minhajur Rahaman , Dipanjan Mitra , George I. Melikidze

A synthesis of the present knowledge on gamma-ray emission from the magnetosphere of a rapidly rotating neutron star is presented, focusing on the electrodynamics of particle accelerators. The combined curvature, synchrotron, and…

Astrophysics · Physics 2009-11-11 Kouichi Hirotani

This paper presents a method of estimation of emission altitudes using observational data - precise measurements of pulse profile widths at low intensity level. The analysis of emission altitudes obtained using this method for a large…

Astrophysics · Physics 2007-05-23 J. Kijak

A model for slow radio pulsars is proposed which involves the entire magnetosphere in the production of the observed radio emission. It is argued that observations of pulsar profiles suggest that a feedback mechanism exists between the star…

Astrophysics · Physics 2009-11-07 G. A. E. Wright
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