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Physics

University of New Hampshire

Galactic cosmic rays

Publication Year

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Measurements Of Galactic Cosmic Ray Shielding With The Crater Instrument, C. Zeitlin, A. W. Case, Harlan E. Spence, Nathan A. Schwadron, M. Golightly, Jody K. Wilson, J. C. Kasper, J. B. Blake, M. D. Looper, J. E. Mazur, L. W. Townsend, Y. Iwata May 2013

Measurements Of Galactic Cosmic Ray Shielding With The Crater Instrument, C. Zeitlin, A. W. Case, Harlan E. Spence, Nathan A. Schwadron, M. Golightly, Jody K. Wilson, J. C. Kasper, J. B. Blake, M. D. Looper, J. E. Mazur, L. W. Townsend, Y. Iwata

Physics & Astronomy

[1] The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument aboard the Lunar Reconnaissance Orbiter has been measuring energetic charged particles from the galactic cosmic rays (GCRs) and solar particle events in lunar orbit since 2009. CRaTER includes three pairs of silicon detectors, separated by pieces of tissue-equivalent plastic that shield two of the three pairs from particles incident at the zenith-facing end of the telescope. Heavy-ion beams studied in previous ground-based work have been shown to be reasonable proxies for the GCRs when their energies are sufficiently high. That work, which included GCR simulations, led to predictions …


The Radiation Environment Near The Lunar Surface: Crater Observations And Geant4 Simulations, M. D. Looper, J. E. Mazur, J. B. Blake, Harlan E. Spence, Nathan A. Schwadron, M. J. Golightly, A. W. Case, J. C. Kasper, L. W. Townsend Apr 2013

The Radiation Environment Near The Lunar Surface: Crater Observations And Geant4 Simulations, M. D. Looper, J. E. Mazur, J. B. Blake, Harlan E. Spence, Nathan A. Schwadron, M. J. Golightly, A. W. Case, J. C. Kasper, L. W. Townsend

Physics & Astronomy

[1] At the start of the Lunar Reconnaissance Orbiter mission in 2009, its Cosmic Ray Telescope for the Effects of Radiation instrument measured the radiation environment near the Moon during the recent deep solar minimum, when galactic cosmic rays (GCRs) were at the highest level observed during the space age. We present observations that show the combined effects of GCR primaries, secondary particles (“albedo”) created by the interaction of GCRs with the lunar surface, and the interactions of these particles in the shielding material overlying the silicon solid-state detectors of the Cosmic Ray Telescope for the Effects of Radiation. We …


Gcr Access To The Moon As Measured By The Crater Instrument On Lro, A. W. Case, Harlan E. Spence, M. J. Golightly, J. C. Kasper, J. B. Blake, J. E. Mazur, L. W. Townsend, C. J. Zeitlin Oct 2010

Gcr Access To The Moon As Measured By The Crater Instrument On Lro, A. W. Case, Harlan E. Spence, M. J. Golightly, J. C. Kasper, J. B. Blake, J. E. Mazur, L. W. Townsend, C. J. Zeitlin

Physics & Astronomy

[1] Recent modeling efforts have yielded varying and conflicting results regarding the possibility that Earth's magnetosphere is able to shield energetic particles of >10 MeV at lunar distances. This population of particles consists of galactic cosmic rays as well as energetic particles that are accelerated by solar flares and coronal mass ejections. The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) onboard the Lunar Reconnaissance Orbiter is in orbit about the Moon and is thus able to directly test these modeling results. Over the course of a month, CRaTER samples the upstream solar wind as well as various regions …


Galactic Cosmic Ray Radiation Hazard In The Unusual Extended Solar Minimum Between Solar Cycles 23 And 24, Nathan A. Schwadron, A. J. Boyd, K. Kozarev, M. Golightly, Harlan E. Spence, L. W. Townsend, M. Owens May 2010

Galactic Cosmic Ray Radiation Hazard In The Unusual Extended Solar Minimum Between Solar Cycles 23 And 24, Nathan A. Schwadron, A. J. Boyd, K. Kozarev, M. Golightly, Harlan E. Spence, L. W. Townsend, M. Owens

Physics & Astronomy

[1] Galactic cosmic rays (GCRs) are extremely difficult to shield against and pose one of the most severe long-term hazards for human exploration of space. The recent solar minimum between solar cycles 23 and 24 shows a prolonged period of reduced solar activity and low interplanetary magnetic field strengths. As a result, the modulation of GCRs is very weak, and the fluxes of GCRs are near their highest levels in the last 25 years in the fall of 2009. Here we explore the dose rates of GCRs in the current prolonged solar minimum and make predictions for the Lunar Reconnaissance …


Assessing Access Of Galactic Cosmic Rays At Moon's Orbit, Chia-Lin L. Huang, Harlan E. Spence, B. T. Kress May 2009

Assessing Access Of Galactic Cosmic Rays At Moon's Orbit, Chia-Lin L. Huang, Harlan E. Spence, B. T. Kress

Physics & Astronomy

[1] Characterizing the lunar radiation environment is essential for preparing future robotic and human explorations on lunar bases. Galactic cosmic rays (GCR) represent one source of ionizing radiation at the Moon that poses a biological risk. Because GCR are charged particles, their paths are affected by the magnetic fields along their trajectories. Unlike the Earth, the Moon has no strong, shielding magnetic field of its own. However, as it orbits Earth, the Moon traverses not only the weak interplanetary magnetic field but also the distant magnetic tail of Earth's magnetosphere. We combine an empirical magnetic field model of Earth's magnetosphere …