KIPT Positron Source Project. Conceptual Design

TL;DR

This paper presents a theoretical and numerical study on designing a slow positron source for KIPT, optimizing target and beam formation parameters, and exploring energy reduction techniques to improve positron moderation.

Contribution

It introduces a comprehensive design approach for a positron source, including target optimization, beam system design, and energy reduction methods, based on simulations and analytical dependencies.

Findings

Optimized target parameters for different electron energies.

Established dependencies of positron beam parameters on magnetic field factors.

Validated subharmonic RF cavity for reducing positron energy.

Abstract

We present the results of theoretical and numerical studies on the source of slow positrons for NSC KIPT. The positrons are intended to generate with the electrons of 9, 40 or 90 MeV available at the KIPT electron linacs. The yield of positrons from the conversion target is estimated as well as their spatial--angular characteristics. Optimal parameters of the conversion target for each energy of electrons are estimated. Preliminary design of the positron beam formation system is also presented. Qualitative analytical dependencies of the positron beam parameters at the system exit upon the amplitude and the decrease factor of the magnetic field in the Adiabatic Matching Device (AMD) solenoid have been established. These dependencies have been used for system optimization. Numerical simulations allow to optimize the parameters of AMD for solenoid available in the laboratory. Possible application of the subharmonic RF cavity for reduction of the energy of positrons has also been estimated and validated by the simulations. As it has been shown, this cavity can substantially decrease the positron energy and thus facilitate operation of the moderator.