Observed diurnal variations in Mars Science Laboratory Dynamic Albedo of Neutrons passive mode data

C. G. Tate, J. Moersch, I. Jun, I. Mitrofanov, M. Litvak, W. V. Boynton, D. Drake, F. Fedosov, D. Golovin, Craig Hardgrove, K. Harshman, A. S. Kozyrev, R. Kuzmin, D. Lisov, E. Maclennan, A. Malakhov, M. Mischna, M. Mokrousov, S. Nikiforov, A. B. Sanin & 2 others R. Starr, A. Vostrukhin

Research output: Contribution to journalArticle

Abstract

The Mars Science Laboratory Dynamic Albedo of Neutrons (DAN) experiment measures the martian neutron leakage flux in order to estimate the amount of water equivalent hydrogen present in the shallow regolith. When DAN is operating in passive mode, it is sensitive to neutrons produced through the interactions of galactic cosmic rays (GCR) with the regolith and atmosphere and neutrons produced by the rover's Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). During the mission, DAN passive mode data were collected over the full diurnal cycle at the locations known as Rocknest (sols 60–100) and John Klein (sols 166–272). A weak, but unexpected, diurnal variation was observed in the neutron count rates reported at these locations. We investigate different hypotheses that could be causing these observed variations. These hypotheses are variations in subsurface temperature, atmospheric pressure, the exchange of water vapor between the atmosphere and regolith, and instrumental effects on the neutron count rates. Our investigation suggests the most likely factors contributing to the observed diurnal variations in DAN passive data are instrumental effects and time-variable preferential shielding of alpha particles, with other environmental effects only having small contributions.

Original languageEnglish (US)
Pages (from-to)70-83
Number of pages14
JournalNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Volume892
DOIs
StatePublished - Jun 1 2018

Fingerprint

diurnal variations
albedo
Neutrons
neutrons
regolith
Sols
thermoelectric generators
atmospheres
Alpha particles
Cosmic rays
Radioisotopes
Shielding
Water vapor
Atmospheric pressure
alpha particles
shielding
Environmental impact
water vapor
atmospheric pressure
leakage

Keywords

  • Dynamic Albedo of Neutrons
  • Mars Science Laboratory
  • Neutron spectrometer

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Instrumentation

Cite this

Observed diurnal variations in Mars Science Laboratory Dynamic Albedo of Neutrons passive mode data. / Tate, C. G.; Moersch, J.; Jun, I.; Mitrofanov, I.; Litvak, M.; Boynton, W. V.; Drake, D.; Fedosov, F.; Golovin, D.; Hardgrove, Craig; Harshman, K.; Kozyrev, A. S.; Kuzmin, R.; Lisov, D.; Maclennan, E.; Malakhov, A.; Mischna, M.; Mokrousov, M.; Nikiforov, S.; Sanin, A. B.; Starr, R.; Vostrukhin, A.

In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 892, 01.06.2018, p. 70-83.

Research output: Contribution to journalArticle

Tate, CG, Moersch, J, Jun, I, Mitrofanov, I, Litvak, M, Boynton, WV, Drake, D, Fedosov, F, Golovin, D, Hardgrove, C, Harshman, K, Kozyrev, AS, Kuzmin, R, Lisov, D, Maclennan, E, Malakhov, A, Mischna, M, Mokrousov, M, Nikiforov, S, Sanin, AB, Starr, R & Vostrukhin, A 2018, 'Observed diurnal variations in Mars Science Laboratory Dynamic Albedo of Neutrons passive mode data', Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, vol. 892, pp. 70-83. https://doi.org/10.1016/j.nima.2018.02.100
Tate, C. G. ; Moersch, J. ; Jun, I. ; Mitrofanov, I. ; Litvak, M. ; Boynton, W. V. ; Drake, D. ; Fedosov, F. ; Golovin, D. ; Hardgrove, Craig ; Harshman, K. ; Kozyrev, A. S. ; Kuzmin, R. ; Lisov, D. ; Maclennan, E. ; Malakhov, A. ; Mischna, M. ; Mokrousov, M. ; Nikiforov, S. ; Sanin, A. B. ; Starr, R. ; Vostrukhin, A. / Observed diurnal variations in Mars Science Laboratory Dynamic Albedo of Neutrons passive mode data. In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 2018 ; Vol. 892. pp. 70-83.
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AU - Litvak, M.

AU - Boynton, W. V.

AU - Drake, D.

AU - Fedosov, F.

AU - Golovin, D.

AU - Hardgrove, Craig

AU - Harshman, K.

AU - Kozyrev, A. S.

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AU - Malakhov, A.

AU - Mischna, M.

AU - Mokrousov, M.

AU - Nikiforov, S.

AU - Sanin, A. B.

AU - Starr, R.

AU - Vostrukhin, A.

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