Presentation
Lower Atmosphere Neutron Detection using Personal Neutron Dosimeters
NCUR 2021
(2021)
Abstract
Measurements from High Altitude Balloon flights provide data for understanding atmospheric cosmic rays. The Regener-Pfotzer (R-P) maximum is the altitude where the ionizing particle count rate reaches an apex due to Galactic Cosmic Ray Showers (GCRS). The flux of secondary GCR particles depends on altitude, latitude, solar activity, and atmospheric composition. Secondary particles consist of ionizing particles, pions, muons, electrons, positrons, and photons. Through interactions, these particles undergo energy loss and decay while traveling through the atmosphere. Neutrons are a part of the secondary interaction. The main interaction layer of the GCRS exists at a higher altitude than that of the R-P maxima which is a result of this interaction. Measuring the neutral maxima in relation to the charged particle intensity directional measurements (horizontal, vertical and omnidirectional) is critical for understanding cosmic ray interactions. It is hypothesized that neutrons are generated in the upper atmosphere due to collisions between the GCR and nuclei of atmospheric oxygen and nitrogen, causing the nuclei to break into atomic and subatomic particles and cause higher numbers of neutrons to occur lower in altitude. An investigation was conducted using a personal neutron dosimeter, paired with a digital camera and Geiger-Müller omnidirectional and directional counters to establish a correlation between neutron counts and the altitude of charged particle maxima. The directional R-P maxima were supported by four Geiger-Müller (RM 80) planar detectors. A majority of neutrons detected passed through the dosimeter at lower altitudes than the directionally measured RP maxima, confirming the hypothesis. A greater occurrence of neutrons appeared below the main interaction layer in the upper atmosphere showing the importance of having charged and neutral detectors used in conjunction with each other to better understand the dynamics of the charged and uncharged particles in the atmospheric environment.
Keywords
- Cosmic Ray showers,
- Geiger-Muller,
- Regener-Pfotzer,
- neutrons,
- High Altitude Balloons
Disciplines
Publication Date
Spring April 14, 2021
Location
Virtual
Comments
Student Presentation at NCUR 21
Citation Information
Anisa Tapper, Gillian Durand, Maddie Ross, Callie Korzeniowski, et al.. "Lower Atmosphere Neutron Detection using Personal Neutron Dosimeters" NCUR 2021 (2021) Available at: http://works.bepress.com/erick-agrimson/38/