In this paper, we describe a study of cosmic ray muon rates and energies at various elevations on Mauna Kea on the island of Hawaii. The study was originally conceived as an extension to the upper-division modern physics laboratory at the University of Hawaii at Hilo and used the TeachSpin Muon Physics apparatus (abbreviated TSMP below) from that lab. The purpose of this paper is to provide a blueprint for similar experiments appropriate to introductory physics laboratory courses and to make students aware of the variety of investigations possible using this type of apparatus. Plans for future work are outlined in the conclusion.
References
1.
2.
This measurement has been carried out using a wide variety of equipment and experimental designs. See, for example,
Henry
Mühry
and Patrick
Ritter
, “Muons in the classroom
,” Phys. Teach.
40
, 294
(May
2002
) or Ref. 3.3.
David H.
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and James H.
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See overview and manual at http://www.ni.com/labview/signalexpress.
6.
For example, see
K. K. M.
Wu
and B. S. K.
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Time constraints primarily dictated the approximately 1400-m intervals between the selected locations. Exact sites and time allotted at each were determined in consultation with the Office of Mauna Kea Management (OMKM) and the National Park Service, which placed additional restrictions based on safety, accessibility, and the presence of culturally sensitive areas surrounding native Hawai’ian ahu (traditional rock piles) and suspected burial sites.
8.
See, for example, subsection 34.2 from Chapter 34 (“Passage of Particles Through Matter”) of the 2017 review of particle properties by the Particle Data Group at LBNL, http://pdg.lbl.gov/2017/reviews/rpp2017-rev-passage-particles-matter.pdf.
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Nalini
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and Douglas A.
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The data were taken by Ken Cicere and his colleagues from the University of Notre Dame as part of the Quarknet program. The raw data were never published and, unfortunately, no longer exist (private communication).
11.
Technical information and assembly instructions are at http://cosmic.lbl.gov/documentation/CosmicDetector2-1.pdf.
12.
Of particular interest are the data from the Berkeley detector presented at Snowmass 2001, viewable at http://cosmic.lbl.gov/SnowMass/main.html.
13.
The current tenuous political situation on Mauna Kea related to construction of the Thirty Meter Telescope has effectively curtailed data-taking opportunities on the mountain. The authors hope that the outlook for cosmology and astrophysics on the Big Island improves soon.
14.
The primary requirements for a lower-division laboratory detector are portability and simplicity. While construction of a Berkeley detector would not be level-appropriate for first- or second-year students, there are alternatives to the TeachSpin detector, such as one developed using Vernier radiation monitors by Bernhard Beck-Winchatz and David Jabon at DePaul University and described at http://www.classroomastronomer.com/resources/muonarticle.pdf.
15.
See Figure 27.2 from Chapter 27 (“Passage of Particles Through Matter”) of the 2011 review of particle properties by the Particle Data Group at LBNL, http://pdg.lbl.gov/2011/reviews/rpp2011-rev-passage-particles-matter.pdf.
16.
See subsection 24.3.1 from Chapter 24 (“Cosmic Rays”) of the 2011 review of particle properties by the Particle Data Group at LBNL, http://pdg.lbl.gov/2011/reviews/rpp2011-rev-cosmic-rays.pdf.
17.
Donald E.
Groom
, Nikolai V.
Mokhov
, and Sergei I.
Striganov
, “Muon stopping power and range tables
,” LBNL-44742
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2001
). Available at http://pdg.lbl.gov/2017/AtomicNuclearProperties/adndt.pdf.18.
Code used in the preparation of this paper, including input and output routines, is available upon request. The Scientific Python (SciPy) module implementing Simpson’s rule for integration is viewable online at the Scipy.org website: https://docs.scipy.org/doc/scipy/reference/generated/scipy.integrate.simps.html.
19.
The ductile iron piping used for the shielding was generously provided at no charge by the Hilo Department of Water Supply. Funding for subsequent cutting and shaping of the shielding was provided by the Hawaii Space Grant Foundation.
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2020
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