Investigation of the relative abundance of heavy versus light nuclei in primary cosmic rays using underground muon bundles

Thesis/Dissertation · Tue Jun 08 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/10166374· OSTI ID:10166374

Sundaralingam, Nakamuthu ^[1]

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1. Tufts Univ., Medford, MA (United States)

We study multiple muon events (muon bundles) recorded underground at a depth of 2090 mwe. To penetrate to this depth, the muons must have energies above 0.8 TeV at the Earth`s surface; the primary cosmic ray nuclei which give rise to the observed muon bundles have energies at incidence upon the upper atmosphere of 10 to 10<sup>5</sup>TeV. The events are detected using the Soudan 2 experiment`s fine grained tracking calorimeter which is surrounded by a 14 m x 10 m x 31 m proportional tube array (the ``active shield``). Muon bundles which have at least one muon traversing the calorimeter, are reconstructed using tracks in the calorimeter together with hit patterns in the proportional tube shield. All ionization pulses are required to be coincident within 3 microseconds. A goal of this study is to investigate the relative nuclear abundances in the primary cosmic radiation around the ``knee`` region (10³ - 10⁴ TeV) of the incident energy spectrum. Four models for the nuclear composition of cosmic rays are considered: The Linsley model, the Constant Mass Composition model (CMC), the Maryland model and the Proton-poor model. A Monte Carlo which incorporates one model at a time is used to simulate events which are then reconstructed using the same computer algorithms that are used for the data. Identical cuts and selections are applied to the data and to the simulated events.

• Research Organization: Tufts Univ., Medford, MA (United States). Dept. of Physics and Astronomy
• Sponsoring Organization: USDOE
• DOE Contract Number: FG02-92ER40702
• OSTI ID: 10166374
• Report Number(s): DOE/ER/40702--3; ON: DE93017601
• Country of Publication: United States
• Language: English

Related Subjects

661300
663300
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
COSMIC MUONS
COSMIC RADIATION
COSMOCHEMISTRY
ELEMENT ABUNDANCE
HEAVY NUCLEI
LIGHT NUCLEI
MONTE CARLO METHOD
MUON DETECTION
NUCLEAR MODELS
NUCLEAR REACTIONS AND SCATTERING
GENERAL
OTHER ASPECTS OF PHYSICAL SCIENCE
PARTICLE DECAY
SHOWER COUNTERS