# The Magnetic Toroidal Sector as A broad-band Electron-Positron Pair   Spectrometer I. Lepton Trajectories

**Authors:** Siegbert Hagmann, Pierre-Michel Hillenbrand, Yurij Litvinov, Uwe, Spillmann, Thomas St\"ohlker

arXiv: 1908.01019 · 2019-10-23

## TL;DR

This paper analyzes a toroidal magnetic sector spectrometer's electron-optical properties, highlighting its high efficiency for detecting electron-positron pairs in heavy-ion collisions, enabling precise tests of theoretical models.

## Contribution

It introduces the design and analysis of a broad-band electron-positron pair spectrometer with high coincidence efficiency for heavy-ion collision studies.

## Key findings

- High efficiency for coincident $e^+e^-$ pair detection
- Wide momentum range coverage for emitted leptons
- Potential for 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. 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 coincident positron- and electron- emission characteristics and for the phase space correlation of lepton vector momenta in free-free pair production.

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Source: https://tomesphere.com/paper/1908.01019