Automatic track recognition for large-angle minimum ionizing particles in nuclear emulsions

TL;DR

This paper demonstrates an automatic system capable of detecting large-angle minimum ionizing particles in nuclear emulsions with over 95% efficiency, aiding current and future particle physics experiments.

Contribution

The study extends an existing automatic track recognition system to effectively identify large-angle minimum ionizing particles with high accuracy.

Findings

Detection efficiency of 95% or higher for large-angle particles

Achieved high angular accuracy in automatic track recognition

Potential applications in various particle physics experiments

Abstract

We previously developed an automatic track scanning system which enables the detection of large-angle nuclear fragments in the nuclear emulsion films of the OPERA experiment. As a next step, we have investigated this system's track recognition capability for large-angle minimum ionizing particles $(1.0 \leq |tan \theta| \leq 3.5)$. This paper shows that, for such tracks, the system has a detection efficiency of 95$\%$ or higher and reports the achieved angular accuracy of the automatically recognized tracks. This technology is of general purpose and will likely contribute not only to various analyses in the OPERA experiment, but also to future experiments, e.g. on low-energy neutrino and hadron interactions, or to future research on cosmic rays using nuclear emulsions carried by balloons.