PSR B1133+16: radio emission height and plasma composition

TL;DR

This paper uses LOFAR observations to constrain the emission height in pulsar PSR B1133+16, arguing that the emission likely originates from a proton-ion plasma rather than an electron-positron plasma, impacting pulsar classification.

Contribution

It demonstrates that the emission region's size and altitude constraints challenge the electron-positron plasma model, proposing proton-ion plasma as a plausible alternative.

Findings

Electron-positron plasma cannot explain the emission constraints.

Proton-ion plasma provides a physically acceptable emission source.

Implications for pulsar classification based on plasma composition.

Abstract

Recent operation of LOFAR by Hassall et al has produced severe constraints on the size and altitude of the 40 MHZ emission region in this pulsar. It is shown that these limits, given a limited number of unexceptionable assumptions, demonstrate that an electron-positron plasma cannot be the source of the emission. A physically-acceptable plasma source composed of protons and ions arises naturally in pulsars having positive corotational polar-cap charge density. Acceptance of this would greatly clarify the classification of pulsar types within the whole.