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JPS Conf. Proc. 11, 040006 (2016) [6 pages]
Proceedings of International Symposium on Radiation Detectors and Their Uses (ISRD2016)
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An Investigation of Elemental Composition of Martian Satellites by Gamma-ray and Neutron Spectrometer
Nobuyuki Hasebe1,2,*, Toru Ohta3, Yoshiharu Amano1,4, Masayuki Naito1, Hiroki Kusano2, Hiroshi Nagaoka2, Kohei Yoshida1, Takuto Adachi1, Timothy J. Fagan3, Haruyoshi Kuno1, Eido Shibamura1, Akira Hitachi1, José A. Matias Lopes5, Jesus Martínez-Frías6, Tomoki Nakamura7, Shingo Kameda8, Yuichiro Cho8, Naoki Shirai9, Hideaki Miyamoto10, Takafumi Niihara10, Takashi Mikouchi11, Tatsuaki Okada12, and Yuzuru Karouji12
1Research Institute for Science and Engineering, Waseda University, Tokyo 169-8555, Japan
2School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
3Geology Department, School of Education, Waseda University, Tokyo 169-8555, Japan
4School of Fundamental Science and Engineering, Waseda University, Tokyo 169-8555, Japan
5Department of Physics, University of Coimbra, 3004-516, Coimbra, Portugal
6CSIC- The Complutense University of Madrid, Madrid 28040, Spain
7Division of Earth and Planetary Materials Science, Tohoku University, Sendai 980-8576, Japan
8Department of Physics, Rikkyo University, Tokyo 171-8501, Japan
9Department of Chemistry, Tokyo Metropolitan University, Tokyo 192-0397, Japan
10The University Museum, The University of Tokyo, Tokyo 153-890, Japan
11Department of Earth and Planetary Sciences, The University of Tokyo, Tokyo 153-8902, Japan
12Japan Aerospace Exploration Agency, Kanagawa 252-5210, Japan
Received February 29, 2016

Japanese mission “Mars Moon eXploration (MMX)” which is currently at the planning stage will make close-up remote and in-situ observations of Phobos and Deimos, and return Phobos samples to Earth. The major scientific objectives of MMX are to characterize geochemical regions in their surface and to determine whether the origin of these Moons is of the captured asteroid or giant impact type. The MMX payload will include a Gamma-ray and Neutron Spectrometer (GNS), which will globally measure and map the surface elemental composition. The GNS consists of a Gamma-ray Sensor (GS) and a Neutron Sensor (NS). The GS consists of a High Purity Germanium (HPGe) detector with an excellent energy resolution as a main detector and a thin plastic scintillator surrounding the HPGe crystal as an anticoincidence detector. The HPGe crystal is cooled below 90 K by a compact mechanical cooler. The NS consists of a Li-glass scintillator to measure thermal neutrons, and a borated plastic scintillator to measure epithermal and fast neutrons. The GNS combines the distinct features of light weight, low power and excellent energy resolution. The GNS will allow to assess the global maps of such elements as H, O, Mg, Al, Si, S, K, Ca, Ti, Fe, Th, and U, depending on their concentrations in the Martian Moons. The high concentration of such volatile elements as H and S in their Moons, and low values of Ca/Fe and Si/Fe-ratios shows that they are solar system primordial bodies, while high values of Ca/F and Si/Fe-ratios and very low water concentration suggest the giant-impact origin. The GNS will allow disentangling weather the origin is captured asteroid or giant impact.

©2016 The Physical Society of Japan
https://doi.org/10.7566/JPSCP.11.040006

References

  • 1) T. M.Harrington et al., Nucl. Instrum. Methods 118, 401 (1974). 10.1016/0029-554X(74)90644-2 Google Scholar
  • 2) W. V.Boynton et al., Space Sci. Rev. 110, 37 (2004). 10.1023/B:SPAC.0000021007.76126.15 Google Scholar
  • 3) W. C.Feldman et al., J. Geophys. Res. 109, E07S06 (2004). 10.1029/2003JE002207 Google Scholar
  • 4) J. O.Goldsten et al., Space Sci. Rev. 131, 339 (2007). 10.1007/s11214-007-9262-7 Google Scholar
  • 5) N.Hasebe et al., Earth Planets Space 60, 299 (2008). 10.1186/BF03352795 Google Scholar
  • 6) T. H.Prettyman et al., Space Sci. Rev. 163, 371 (2011). 10.1007/s11214-011-9862-0 Google Scholar
  • 7) K. J.Kim and N.Hasebe, Res. Astron. Astrophys. 12, 1313 (2012). 10.1088/1674-4527/12/10/001 Google Scholar
  • 8) R. C.Reedy, Proc. 9th LPSC, Pergamon Press, 1978, Vol. 3, p. 2961.Google Scholar
  • 9) T. H.Prettyman, Encyclopedia of the Solar System, ed. T.Spohn, T.Johnson, and D.Bleuer, (Elsevier, 2015) 3rd ed., p. 1161.Google Scholar
  • 10) A. A.Fraeman et al., Icarus 229, 196 (2014). 10.1016/j.icarus.2013.11.021 Google Scholar
  • 11) N.Schmedemann et al., Planet. Space Sci. 102, 152 (2014). 10.1016/j.pss.2014.04.009 Google Scholar
  • 12) N.Thomas et al., Planet. Space Sci. 59, 1281 (2011). 10.1016/j.pss.2010.04.018 Google Scholar
  • 13) O.Witasse et al., Planet. Space Sci. 102, 18 (2014). 10.1016/j.pss.2013.08.002 Google Scholar
  • 14) R. I.Citron, H.Genda, and S.Ida, Icarus 252, 334 (2015). 10.1016/j.icarus.2015.02.011 Google Scholar
  • 15) P.Rosenblatt and S.Charnoz, Icarus 221, 806 (2012). 10.1016/j.icarus.2012.09.009 Google Scholar
  • 16) R. A.Craddock, Icarus 211, 1150 (2011). 10.1016/j.icarus.2010.10.023 Google Scholar
  • 17) W. C.Feldman et al., Science 281, 1489 (1998). 10.1126/science.281.5382.1489 Google Scholar
  • 18) T. H.Prettyman et al., Met. Plan. Sci. 48, 2211 (2013). 10.1111/maps.12244 Google Scholar
  • 19) D. J.Lawrence et al., Science 339, 292 (2013). 10.1126/science.1229953 Google Scholar
  • 20) D. J.Lawrence et al., J. Geophys. Res. 111, E08001 (2006). 10.1029/2005JE002637 Google Scholar
  • 21) W. C.Feldman et al., Science 281, 1489 (1998). 10.1126/science.281.5382.1489 Google Scholar
  • 22) E.Jarosewich, Meteoritics 25, 323 (1990). 10.1111/j.1945-5100.1990.tb00717.x Google Scholar
  • 23) National Aeronautics and Space Administration [http://curator.jsc.nasa.gov/antmet/mmc/].Google Scholar
  • 24) K.Yoshida et al., Jpn. Phys. Soc. this Conf. Proceedings.Google Scholar
  • 25) M.Naito et al., Jpn. Phys. Soc. this Conf. Proceedings.Google Scholar
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