spase://CNES/NumericalData/CDPP-AMDA/MAVEN/SWIA/mavpds-swia-momboard

PDS

/maven-swia-calibrated/onboard_svy_mom

ThermalPlasma

Mars

The moments are computed under the assumption that all ions are protons, and that the entire distribution is within the field of view and the energy range of the instrument. Meanwhile, there is no quality flag or correction for multi-ion issues. Thus, SWIA moments data taken inside the induced magnetospheric boundary should typically not be used for quantitative purposes. Even in the solar wind, which is ~94-97% protons, there are some values which cannot be used quantitatively, since the moments are computed over a distribution which includes not only the protons, but also ~3-6% alpha particles with twice the energy per charge. This has only a few percent effect on the density and velocity moments, so these values can safely be relied on, but even a small alpha population leads to an artificially large temperature moment (particularly the component aligned with the flow, which is often 2x or more higher than the true value). Thus, the SWIA temperature moments cannot typically be used for quantitative purposes [for qualitative purposes they may be okay in the solar wind and magnetosheath]. Those wishing to look quantitatively at solar wind temperature should use the SWIA Level 2 3-d Fine data and use appropriate routines to separately compute proton and alpha temperature.