Measuring ionizing radiation in the atmosphere with a new balloon-borne detector

TL;DR

This paper introduces a new miniature scintillator-based detector designed for balloon deployment to measure atmospheric ionizing radiation, providing insights into energetic particle effects on weather and climate.

Contribution

The paper presents the development, calibration, and successful high-altitude testing of a novel detector capable of measuring a wide range of ionizing radiation in the atmosphere.

Findings

Detector responds to gamma rays up to 17 MeV

Successfully measured muons and cosmic ray particles at 25 km altitude

Identified transition from terrestrial gamma to high-energy particles in the atmosphere

Abstract

Increasing interest in energetic particle effects on weather and climate has motivated development of a miniature scintillator-based detector intended for deployment on meteorological radiosondes or unmanned airborne vehicles. The detector was calibrated with laboratory gamma sources up to 1.3 MeV, and known gamma peaks from natural radioactivity of up to 2.6 MeV. The specifications of our device in combination with the performance of similar devices suggest that it will respond to up to 17 MeV gamma rays. Laboratory tests show the detector can measure muons at the surface, and it is also expected to respond to other ionizing radiation including, for example, protons, electrons (>100 keV) and energetic helium nuclei from cosmic rays or during space weather events. Its estimated counting error is about 10%. Recent tests, when the detector was integrated with a meteorological radiosonde system, and carried on a balloon to ~25 km altitude, identified the transition region between energetic particles near the surface, which are dominated by terrestrial gamma emissions, to higher-energy particles in the free troposphere.