A Magnetic Spectrometer for Electron-Positron Pair Spectroscopy in Storage Rings

TL;DR

This paper analyzes a toroidal magnetic spectrometer's electron-optical properties for electron-positron pair detection in heavy-ion storage rings, highlighting its high efficiency and potential for testing theoretical models.

Contribution

It introduces a detailed analysis of a magnetic spectrometer design optimized for high-efficiency electron-positron pair spectroscopy in storage rings.

Findings

High efficiency for coincident $e^+e^-$ pair detection

Suitable for wide momentum range of emitted leptons

Enables stringent tests of pair production theories

Abstract

We report an analysis of electron-optical properties of a toroidal magnetic sector spectrometer and examine parameters for its implementation in a relativistic heavy-ion storage ring like HESR at the future FAIR facility. For studies of free-free pair production in heavy-ion atom collisions, this spectrometer exhibits very high efficiencies for coincident $e^+e^-$ pair spectroscopy over a wide range of momenta of emitted lepton pairs. The high coincidence efficiency of the spectrometer is the key for stringent tests of theoretical predictions for the phase space correlation of lepton vector momenta in free-free pair production.