Active optical fibres in modern particle physics experiments

TL;DR

This paper reviews the use of active optical fibres in particle physics, focusing on photon trapping, transmission, timing, and practical considerations for high-rate experiments.

Contribution

It provides a comprehensive analysis of photon trapping efficiencies, transmission functions, and timing resolution limitations in modern active optical fibres.

Findings

Numerical simulations of skew ray tracking reveal light characteristics in curved fibres.

Parametrisations of transmission functions aid in design optimization.

Timing resolution is limited by photon path length variations.

Abstract

In modern particle physics experiments wavelength-shifting and scintillating fibres based on plastic polymers are used for tracking and calorimetry. In this review the role of photon trapping efficiencies, transmission functions and signal response times for common multimode active fibres is discussed. Numerical simulations involving three dimensional tracking of skew rays through curved fibres demonstrate the characteristics of trapped light. Of practical interest are the parametrisations of transmission functions and the minimum permissible radius of curvature. These are of great importance in today's experiments where high count rates and small numbers of photoelectrons are encountered. Special emphasis has been placed on the timing resolution of fibre detectors and its limitation due to variations in the path length of generated photons.