From: arXiv.org e-Print archive
Posted: Monday, May 22, 2017
Jingnan Guo, Cary Zeitlin, Robert F. Wimmer-Schweingruber, Thoren McDole, Patrick Kuehl, Jan C. Appel, Johannes Krauss, Jan Koehler
(Submitted on 9 May 2017)
For future human missions to Mars, it is important to study the surface radiation environment during extreme and elevated conditions. In the long term, it is mainly Galactic Cosmic Rays (GCRs) modulated by solar activity that contributes to the radiation on the surface of Mars, but intense solar energetic particle (SEP) events may induce acute health effects. Such events may enhance the radiation level significantly and should be detected as immediately as possible to prevent severe damage to humans and equipment. However, the energetic particle environment on the Martian surface is significantly different from that in deep space due to the influence of the Martian atmosphere, and, to a lesser extent, the regolith. Depending on the intensity and shape of the original solar particle spectra as well as particle types, the surface spectra may induce entirely different radiation effects. For instance, an intense SEP event with a soft spectrum that would be hazardous on the lunar surface may, in contrast, induce only low levels of radiation on the Martian surface that would be well within human health tolerances. In order to give immediate and accurate alerts while avoiding unnecessary ones, it is important to model and well understand the atmospheric effect on the incoming SEPs including both protons and helium ions. In this paper, we have developed a generalized approach to quickly model the surface response of any given incoming proton/helium ion spectra and have applied it to a set of historical large solar events, thus providing insights into the possible variety of surface radiation environments that may be induced during SEP events.
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM); Space Physics (physics.space-ph)
Cite as: arXiv:1705.06763 [astro-ph.EP]
(or arXiv:1705.06763v1 [astro-ph.EP] for this version)
From: Jingnan Guo Dr.
[v1] Tue, 9 May 2017 14:38:43 GMT (815kb,D)
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