Nuclear Track Detectors. Searches for Exotic Particles

TL;DR

This paper discusses the use of Nuclear Track Detectors (NTD) for calibrations, searches for exotic particles like magnetic monopoles, nuclearites, Q-balls, strangelets, and environmental radiation monitoring, providing upper flux limits.

Contribution

It reports new experimental upper limits on fluxes of exotic particles using large-scale NTD experiments in underground and high-altitude settings.

Findings

Established upper limit for GUT monopoles at 1.4x10^-16 cm^-2 s^-1 sr^-1

Set upper limit for Intermediate Mass Monopoles at 1.3x10^-15 cm^-2 s^-1 sr^-1

Performed environmental radiation and neutron dosimetry studies

Abstract

We used Nuclear Track Detectors (NTD) CR39 and Makrofol for many purposes: i) Exposures at the SPS and at lower energy accelerator heavy ion beams for calibration purposes and for fragmentation studies. ii) Searches for GUT and Intermediate Mass Magnetic Monopoles (IMM), nuclearites, Q-balls and strangelets in the cosmic radiation. The MACRO experiment in the Gran Sasso underground lab, with ~1000 m^2 of CR39 detectors (plus scintillators and streamer tubes), established an upper limit for superheavy GUT poles at the level of 1.4x10^-16 cm^-2 s^-1 sr^-1 for 4x10^-5 <beta<1. The SLIM experiment at the high altitude Chacaltaya lab (5230 m a.s.l.), using 427 m^2 of CR39 detectors exposed for 4.22 y, gave an upper limit for IMMs of ~1.3x10^-15 cm^-2 s^-1 sr^-1. The experiments yielded interesting upper limits also on the fluxes of the other mentioned exotic particles. iii) Environmental studies, radiation monitoring, neutron dosimetry.