Cosmic ray muon charge ratio in the MINOS far detector

Thesis/Dissertation · Thu Dec 01 00:00:00 EST 2005

DOI:https://doi.org/10.2172/892438· OSTI ID:892438

Beall, Erik B. ^[1]

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1. Univ. of Minnesota, Minneapolis, MN (United States)

The MINOS Far Detector is a 5.4 kiloton (5.2 kt steel plus 0.2 kt scintillator plus aluminum skin) magnetized tracking calorimeter located 710 meters underground in the Soudan mine in Northern Minnesota. MINOS is the first large, deep underground detector with a magnetic field and thus capable of making measurements of the momentum and charge of cosmic ray muons. Despite encountering unexpected anomalies in distributions of the charge ratio (N{sub μ⁺/N_μ^-) of cosmic muons, a method of canceling systematic errors is proposed and demonstrated. The result is R_eff = 1.346 ± 0.002 (stat) ± 0.016 (syst) for the averaged charge ratio, and a result for a rising fit to slant depth of R(X) = 1.300 ± 0.008 (stat) ± 0.016 (syst) + (1.8 ± 0.3) x 10^-5 x X, valid over the range of slant depths from 2000 < X < 6000 MWE. This slant depth range corresponds to minimum surface muon energies between 750 GeV and 5 TeV.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76CH03000
• OSTI ID: 892438
• Report Number(s): FERMILAB-THESIS-2005-74; TRN: US200704%%419
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ALUMINIUM
CALORIMETERS
COSMIC MUONS
MAGNETIC FIELDS
MINUS-PLUS RATIO
MUONS
PHOSPHORS
STEELS
Experiment-HEP