On the motion of high-energy wave packets and the transition radiation by "half-bare'' electron

TL;DR

This paper investigates the behavior of high-energy electromagnetic wave packets and how transition radiation from 'half-bare' ultrarelativistic electrons varies depending on target placement relative to the coherence length.

Contribution

It provides new insights into the transformation of wave packets over long distances and the distinct transition radiation characteristics of 'half-bare' electrons.

Findings

Wave packets transform into diverging spherical waves over long distances

Transition radiation differs significantly inside and outside the coherence length

The study enhances understanding of radiation from ultrarelativistic electrons

Abstract

The problem of the motion of high-energy wave packets combined of free electromagnetic waves is considered. It is demonstrated that the transformation of such packets to the packet of spherically diverging waves happens on long distances along the packet's motion direction, that substantially exceed the radiated wavelength. The transition radiation by the ``half-bare'' ultrarelativistic electron is considered. It is demonstrated that the transition radiation by such an electron on the targets located inside and outside the coherence length of the radiation process would be substantially different.