On the particle production threshold for ultra-relativistic accelerated protons

TL;DR

This paper investigates the threshold of particle acceleration necessary for massive particle emission, emphasizing the role of classical and proper acceleration, with implications for cosmic ray physics and pulsar environments.

Contribution

It introduces the acceleration as a key parameter for particle emission thresholds and applies this to assess meson production in pulsar magnetic fields.

Findings

Acceleration threshold determines massive particle emission viability.

Meson production by protons is significant in strong magnetic fields.

Classical and proper acceleration are crucial for understanding cosmic ray emissions.

Abstract

Non-electromagnetic emission from cosmic ray particles accelerated in extreme environments has been studied using different variations of semi-classical formalisms. As the energy loss mechanisms of such particles is of great interest, one must improve in some sense the previously intuitive description of classical sources in the presence of fields. In this brief note we evaluate the role played by the classical and dimensional proper acceleration of a particle in radiation processes. One intends to show that the introduction of the acceleration as a measure parameter gives an adequate scale for considering the processes of massive particle emission. If the acceleration threshold is not attained one is considering a regime where the processes of massive particle production are suppressed. The analysis is performed in a semiclassical formalism once applied in different contexts and already checked for consistency in a serie of papers. As a further application of the results we evaluate the possibility of a non negligible meson production by protons accelerated in the framework of polar cap models operating in electromagnetic fields of pulsars. It is shown that inside a systems endowed with magnetic fields B\geq 10^{12} G the meson emission by protons must not be disregarded.