Measurement of Lateral Distribution of Cosmic Rays Muons Using Two-Fold Coincidence Technique
Loading...
Date
2024-09
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Kenyatta University
Abstract
Charged primary cosmic ray particles constitute 85% protons, 12% helium, 3% iron,
and heavier elements. These primary particles interact with the Earth's atmosphere,
producing secondary particles known as Extensive Air Showers (EAS). Among the
particles produced in EAS are pions and kaons, which subsequently decay into muons.
Cosmic ray muons dominate the population of cosmic ray particles on the Earth's
surface. Understanding the properties of EAS in the Earth's atmosphere is the aim of
this investigation. The lateral distribution of cosmic ray muons was investigated using
two-fold coincidences. Four detectors were positioned at two-fold coincidence
separated from 0 to 35.5 meters at regular intervals. It was determined what the
coincidence rate was between these detector stations. The data that was collected
was fitted using the Nishimura-Kamata-Greisen (NKG) function in order to examine
the lateral distribution The results showed that the muon flux decreased with increasing
distance. Additionally, the study aimed to explore the hourly variation of cosmic ray
muon flux. To achieve this, two detectors were used in coincidence to measure the
variation over time. The highest muon flux was observed sometime after midmorning
and lowest sometime after sunset. To support the understanding of EAS, Monte Carlo
(MC) simulations of EAS were performed using the EPOS and GHEISHA models,
which account for high and low-energy particle interactions, respectively. The
simulations using EPOS LHC from this work with the measurements of the two-fold
coincidence gave a primary composition cosmic ray as (protons (81±0.01) %, helium
(10±0.04) %, and (9±5.88) % iron, and heavier elements). The EPOS LHC simulations
were then compared to the experimental data and the muon count rate was found to
align with the expected one. The knowledge gained from the lateral distribution of
cosmic ray muons is essential for comprehending the development of extensive air
showers. Furthermore, this information enhances our understanding of the chemical
composition of primary cosmic ray particles. In addition, we also understand the
interactions of cosmic ray particles in the atmosphere, particle production and
formation of EAS
Description
A Thesis Submitted in Partial Fulfillment of the Requirements for the Award of Degree of Master of Science (Physics) In the School of Pure and Applied Sciences of Kenyatta University, September 2024.
1.Nadir O. Hashim
2.Naftali Kimani