Abstract:
We consider the problem of taking into account radiation losses in describing the dynamics of a charged particle in electromagnetic fields. The solution of this fundamental problem is becoming more and more in demand due to the development of ultra-high-power lasers. Since the generation of radiation by a charged particle depends both on the magnitude of the fields in which it moves and on their structure, the developed multipetawatt multibeam laser systems, such as XCELS, can open up unique ways to solve this problem. In the present work, one of such ways is proposed, based on the use of a magnetic dipole field configuration formed by several laser pulses. Using numerical simulations, we show that when a solid target in the form of a nanowire is irradiated with several petawatt laser pulses that maximise the magnetic field at the focus, there appears an anomalous radiative capture regime. The generated distributions of accelerated electrons and generated gamma photons in this regimes have distinctive properties, on the basis of which it is possible to experimentally determine the applicability of various theoretical approaches to the description of radiation losses.