Poster Presentation

Flying Cloud Chambers on Stratospheric Balloon Missions

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Abstract

Cloud chambers allow for visualizing the trajectory of radiation within a supersaturated vapor. When radiation interacts with the vapor, droplets become ionized and form visible trails along the particle’s trajectory. We have developed a lightweight cloud chamber and flown it on several stratospheric balloon missions. During a stratospheric balloon flight, the amount of cosmic radiation exposure, and hence the visible trail activity within a cloud chamber, is expected to increase dramatically with altitude due to increasing amounts of cosmic radiation that penetrate the atmospheric overburden. On our stratospheric balloon flights, the peak of cloud chamber visible activity occurred around 68,000 ft, with unexpectedly-few trails seen at higher altitudes. The main trails observed are believed to be from high and low-energy electrons, protons, and some muons. The process of deciphering which particles the trails relate to was done by comparing our images and footage to cloud chamber results from the literature. In addition to identifying the different types of particles, we want to develop an automated method to visually count the number of events that occur within the chamber from camera footage, much like a Geiger counter counts individual hits. During flights we did observe an increase in activity, evidenced by more-frequent trail formation in the chamber. However, as the flight progressed above 80,000 ft, the decreasing pressure produced an unstable supersaturated vapor environment in which individual trails could no longer be seen. Put another way, we were unable to maintain a supersaturated cloud in a low-pressure environment. A pressure-tight cloud chamber might be one way to work around this issue, but such a device is likely to be too heavy to fly on small weather balloons. Hence, we intend to use vacuum chamber ground testing to explore various ideas for maintaining a cloud environment over the wide range of atmospheric pressures experienced during stratospheric balloon flights. Additional future steps include trying to better-understand both the amount of cosmic radiation and the distribution of types of particles present at different altitudes in the troposphere and stratosphere. Particle identification might be enhanced by observing how particle trajectories are influenced by an applied magnetic field.

Keywords: cloud chamber, stratosphere, stratospheric ballooning, weather balloon

How to Cite:

Robles, M., Kamenshikova, A. & Flaten, J., (2025) “Flying Cloud Chambers on Stratospheric Balloon Missions”, Academic High Altitude Conference 2025(1). doi: https://doi.org/10.31274/ahac.20146