2.3.1 spase://CNES/NumericalData/CDPP-AMDA/IMP-8/MIT/imp-mit-k0 best fit IMP 8 Solar Wind Plasma Faraday Cup Data 2015-10-16T16:25:59Z The MIT Faraday cup experiment on IMP 8 measures currents from solar wind ions, and from these measurements we calculate the velocity, density, and temperature of the solar wind. The IMP 8 data files consist of fine resolution data (approximately 1 minute resolution). IMP 8 spins with a period of approximately 2.7s. The Faraday Cup (FC) instrument scans the solar wind distribution stepping through a contiguous set of energy windows, one step per spacecraft spin. The FC instrument divides the spin into thirty-two, 11.25 degree angular sectors and integrates the measured currents over different angular sectors depending upon the Mode in which the instrument is operating. The border between two of the 11.25 degree angular sectors lies on the Sun-spacecraft line. The FC sensor collector plate is divided into two, semi-circular halves; the division line is parallel to the spacecraft spin plane which is approximately parallel to the ecliptic plane. The split collector allow determination of the bulk plasma flow relative to the spin plane; North/South angles refer to flows coming from above or below the spin plane respectively (flows from the South are designated as having a positive N/S angle). The bulk flow angle in the spin plane is determined from the measurements of current vs. rotation angle. The currents telemetered to the ground are the sums of currents for the two half-collectors ("A" and "B") and, for the TMS and AQM modes, also the current for the half-collector "B". Electrons are measured except for the eight angles near the Sun. The experiment has two memories only one of which is operating perfectly. As a result, only every other TMS spectrum is usable, and the time between spectra is usually twice that that would be expected from the spacecraft spin rate. The bad half-memory also limits the energy windows that can be used in the other modes, since they require both memories to hold the data. On occasion, the data are read out rapidly enough by the spacecraft to allow repeated use of the good half-memory, and the time resolution in the TMS is approximately 32 seconds. For papers and presentations using these data, please acknowledge the MIT Space Plasma Physics Group and the path through which you accessed the data. spase://SMWG/Person/Alan.J.Lazarus PrincipalInvestigator spase://SMWG/Person/John.D.Richardson TeamMember Readme file at SPDF ftp://spdf.gsfc.nasa.gov/pub/data/imp/imp8/plasma_mit/sw_msheath_min/00readme.txt Text created by MIT IMP8 plasma team spase://SMWG/Repository/CDPP/AMDA Online Open AMDA at CDPP http://amda.cdpp.eu NetCDF NSSDC Calibrated spase://CDPP/Instrument/AMDA/IMP8/PLS ThermalPlasma 1973-10-31T20:10:27Z 2006-07-26T17:10:35Z PT58S Heliosphere.NearEarth Earth.Magnetosheath density imp_mit_nfit (Better, from fits) Proton number density phys.density;phys.atmol.ionStage cm^-3 1e6>m^-3 TimeSeries 0.0 100.0 9999.0 Proton Ion Fit Scalar NumberDensity v_bulk imp_mit_vfit (Better, from fits) Ion Flow Velocity (aberration corrected) phys.veloc;phys.atmol.ionStage km/s 1e3>m/s Spherical GSE TimeSeries 100.0 3000.0 9999.0 Proton Ion Fit Magnitude FlowVelocity v_thermal imp_mit_vthfit (Better, from fits) Proton most-probable thermal speed (aberration corrected). Thermal speed is the most probable thermal speed (i.e., the square root of [2kT/m(proton)]). To convert thermal speed to temperature in eV, multiply 0.0052 by the square of the thermal speed; to convert to temperature [K], multiply the square of the thermal speed by 60.5. phys.veloc;phys.atmol.ionStage km/s 1e3>m/s TimeSeries 1.0 500.0 9999.0 Proton Ion Fit Scalar ThermalSpeed flow angle e/w imp_mit_velewfit (Best, from fits) Proton East/West flow angle (aberration corrected). Azimuth is E/W, meaning bulk flow from the East or the West side of the Sun respectively. Positive azimuth angle means flow from the West. pos.posAng;phys.veloc;phys.atmol.ionStage deg Spherical GSE TimeSeries -45.0 45.0 9999.0 Proton Ion Fit DirectionAngle.AzimuthAngle FlowVelocity flow angle n/s imp_mit_velnsfit (Best, from fits) Proton North/South flow angle (aberration corrected). Azimuth is N/S, meaning bulk flow from the North or the South side of the Sun respectively. Positive azimuth angle means flow from the North. pos.posAng;phys.veloc;phys.atmol.ionStage deg Spherical GSE TimeSeries -45.0 45.0 9999.0 Proton Ion Fit DirectionAngle.AzimuthAngle FlowVelocity