2.3.1 spase://CNES/NumericalData/CDPP-AMDA/MAVEN/SWIA/mavpds-swia-momboard onboard ion moments 2015-10-12T10:48:29Z Onboard Survey Moments - Ion density, temperature, and velocity moments in physical units and coordinates calculated onboard from SWIA coarse or fine data (depending on mode). These 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. Principal Investigator : Jasper Halekas, Univ. Iowa, Iowa City spase://CNES/Person/Jasper.S.Halekas PrincipalInvestigator SWIA web page, Summary sheet http://lasp.colorado.edu/home/maven/science/instrument-package/swia/ spase://SMWG/Repository/CNES/CDPP-AMDA Online Open AMDA at CDPP http://amda.cdpp.eu Text.ASCII AMDA is a science analysis system provided by the Centre de Donnees de la Physique des Plasmas (CDPP) supported by CNRS, CNES, Observatoire de Paris and Universite Paul Sabatier, Toulouse PDS /maven-swia-calibrated/onboard_svy_mom spase://CNES/Instrument/CDPP-AMDA/MAVEN/SWIA ThermalPlasma 2014-03-19T14:19:43Z 2018-08-15T00:00:55Z PT4S 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. density mav_swia_n phys.density;phys.atmol.ionStage cm-3 Ion NumberDensity v_mso mav_swia_vmso phys.veloc;phys.atmol.ionStage km/s 3 vx Component 1 mav_swia_vmso(0) vy Component 2 mav_swia_vmso(1) vz Component 3 mav_swia_vmso(2) Ion Velocity |v| mav_swia_vtot phys.veloc;phys.atmol.ionStage km/s Ion Velocity t_msomav_swia_tmso phys.temperature;phys.atmol.Ionstage eV 3 txx Component 1 mav_swia_tmso(0) tyy Component 2 mav_swia_tmso(1) tzz Component 3 mav_swia_tmso(2) Ion Temperature