{ "Spase": { "xmlns": "http://www.spase-group.org/data/schema", "xmlns:xsi": "http://www.w3.org/2001/XMLSchema-instance", "xsi:schemaLocation": "http://www.spase-group.org/data/schema https://www.spase-group.org/data/schema/spase-2_3_2.xsd", "Version": "2.3.2", "NumericalData": { "ResourceID": "spase://NASA/NumericalData/IMP8/PLS/PT01M", "ResourceHeader": { "ResourceName": "IMP 8 MIT Full Resolution Definitive Interplanetary Plasma Data", "AlternateName": "IMP 8 Solar Wind Plasma Faraday Cup Data", "ReleaseDate": "2021-04-27T15:38:11Z", "Description": "The MIT Faraday cup experiment on IMP 8 measures \ncurrents from solar wind ions, and from these measurements we calculate \nthe velocity, density, and temperature of the solar wind. The IMP 8 data \nfiles consist of fine resolution data (approximately 1 minute resolution).\n\n IMP 8 spins with a period of approximately 2.7s. The Faraday \nCup (FC) instrument scans the solar wind distribution stepping through a \ncontiguous set of energy windows, one step per spacecraft spin. The FC \ninstrument divides the spin into thirty-two, 11.25 degree angular sectors \nand integrates the measured currents over different angular sectors \ndepending upon the Mode in which the instrument is operating. The border \nbetween two of the 11.25 degree angular sectors lies on the Sun-spacecraft \nline.\n\n The FC sensor collector plate is divided into two, \nsemi-circular halves; the division line is parallel to the spacecraft spin \nplane which is approximately parallel to the ecliptic plane. The split \ncollector allow determination of the bulk plasma flow relative to the spin \nplane; North/South angles refer to flows coming from above or below the \nspin plane respectively (flows from the South are designated as having a \npositive N/S angle).\n\n The bulk flow angle in the spin plane is determined from the \nmeasurements of current vs. rotation angle. The currents telemetered to \nthe ground are the sums of currents for the two half-collectors (\"A\" and \n\"B\") and, for the TMS and AQM modes, also the current for the \nhalf-collector \"B\".\n\n Electrons are measured except for the eight angles near the Sun.\n\n The experiment has two memories only one of which is operating \nperfectly. As a result, only every other TMS spectrum is usable, and the \ntime between spectra is usually twice that that would be expected from the \nspacecraft spin rate. The bad half-memory also limits the energy windows \nthat can be used in the other modes, since they require both memories to \nhold the data. On occasion, the data are read out rapidly enough by the \nspacecraft to allow repeated use of the good half-memory, and the time \nresolution in the TMS is approximately 32 seconds.", "Acknowledgement": "For papers and presentations using these data, \nplease acknowledge the MIT Space Plasma Physics Group and the path through\nwhich you accessed the data.", "Contact": [ { "PersonID": "spase://SMWG/Person/Alan.J.Lazarus", "Role": "PrincipalInvestigator" }, { "PersonID": "spase://SMWG/Person/John.D.Richardson", "Role": "TeamMember" } ], "InformationURL": { "Name": "Readme file at SPDF", "URL": "https://spdf.gsfc.nasa.gov/pub/data/imp/imp8/plasma_mit/sw_msheath_min/00readme.txt", "Description": "Text created by MIT IMP8 plasma team" }, "PriorID": [ "spase://VMO/NumericalData/IMP8/PLS/PT01M", "spase://VSPO/NumericalData/IMP8/PLS/PT01M" ] }, "AccessInformation": [ { "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF", "Availability": "Online", "AccessRights": "Open", "AccessURL": [ { "Name": "FTPS from SPDF (not with most browsers)", "URL": "ftps://spdf.gsfc.nasa.gov/pub/data/imp/imp8/plasma_mit/" }, { "Name": "HTTPS from SPDF", "URL": "https://spdf.gsfc.nasa.gov/pub/data/imp/imp8/plasma_mit/", "Description": "In CDF via HTTP from SPDF" } ], "Format": "CDF" }, { "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF", "Availability": "Online", "AccessRights": "Open", "AccessURL": [ { "Name": "CDAWeb", "URL": "https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=I8_H0_MITPLASMA&index=sp_phys", "ProductKey": "I8_H0_MITPLASMA", "Description": "With subset, plot and list functionalities" }, { "Name": "FTPBrowser", "URL": "https://omniweb.sci.gsfc.nasa.gov/ftpbrowser/imp_mit_min.html", "Description": "With subset, plot and list functionalities" } ], "Format": "Text" }, { "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF", "Availability": "Online", "AccessRights": "Open", "AccessURL": { "Name": "CDAWeb HAPI Server", "URL": "https://cdaweb.gsfc.nasa.gov/hapi", "Style": "HAPI", "ProductKey": "I8_H0_MITPLASMA", "Description": "Web Service to this product using the HAPI interface." }, "Format": "CSV" } ], "ProcessingLevel": "Calibrated", "ProviderVersion": "v01", "InstrumentID": "spase://SMWG/Instrument/IMP8/PLS", "MeasurementType": "ThermalPlasma", "TemporalDescription": { "TimeSpan": { "StartDate": "1973-10-31T20:10:26", "StopDate": "2006-07-26T17:10:34" }, "Cadence": "PT01M" }, "ObservedRegion": [ "Heliosphere.NearEarth", "Earth.Magnetosheath" ], "Caveats": "\n The cadence varies slightly (by a few seconds) and is approximately 1 minute.\n\n The parameter values are derived from taking moments of the \ndistributions and from fits to the distributions. As can be seen \neasily by eye, there is some discrepancy between moments and our \nbest (fit) parameters; moments are definitely less accurate.\n\n Use moment values with caution, and PLEASE request assistance \nor clarification. For the moment parameters, changes in value are more \ntrustworthy than absolute values, but nothing is guaranteed to be \naccurate.\n\n A value of 9999.0 means that we couldn't calculate that \nparameter. All parameters are based on a convected, isotropic \nMaxwellian model.\n\n The moment values, for angles and for the speed, do NOT have \naberration corrections included. This means that the total speeds are \nslightly too low, and that the angles are not really correct. In \nparticular, the azimuthal (E/W) angle is about 4 degrees too positive; \nthis can clearly be seen where both nonlinear and moment angles are \navailable.\n\n If good angles cannot be obtained, there won't be any \nvelocity components; speeds are available in some such cases.\n\n Dr. Joseph King (NASA/GSFC) has looked at 27-day averages of \nOMNIWeb data from 1984-1994. He finds (and the MIT team agrees) that \nthere is an offset of about +2 degrees (from the South) in the N/S \nangle and an annual variation of that angle with an amplitude of \nabout 1 degree. The MIT team believes that the annual variation is \ndue to a tilt of the s/c spin axis. He found the mean flow longitude \nin that study to be -0.3 degrees with no obvious annual variation.", "Parameter": [ { "Name": "Time", "ParameterKey": "Epoch", "Description": "Time", "Caveats": "The cadence varies by a few seconds and is \napproximately 1 minute. ValidMin and ValidMax values in the CDF files \nare incorrect, do not use.", "FillValue": "-1.0E31", "Support": { "Qualifier": "Scalar", "SupportQuantity": "Temporal" } }, { "Name": "Spacecraft", "ParameterKey": "Spacecraft", "Description": "Spacecraft flag (6/7/8 = IMP 6/7/8)", "ValidMin": "0", "ValidMax": "8", "FillValue": "9", "Support": { "SupportQuantity": "Other" } }, { "Name": "Decimal Year", "ParameterKey": "decimal_year", "Description": "Decimal year", "ValidMin": "1972.0", "ValidMax": "2020.0", "FillValue": "100000.0", "Support": { "Qualifier": "Scalar", "SupportQuantity": "Temporal" } }, { "Name": "Region", "ParameterKey": "Region", "Description": "Region flag provides an estimate of the region from \nwhich the data came.\n\n There are three flag values:\n \n * 1 - This time is definitely solar wind.\n * 2 - This time is either solar wind or magnetosheath, with no \ndifferentiation being made. This designation is used for multiple crossings \nbetween the solar wind and sheath regions.\n * 3 - This time is definitely NOT solar wind, being either \nmagnetosheath or magnetospheric data.", "ValidMin": "1", "ValidMax": "8", "FillValue": "9", "Support": { "SupportQuantity": "Other" } }, { "Name": "Operating mode", "ParameterKey": "mode", "Description": "Indicates the operating mode of the experiment. The following table describes the measurements for each mode.\n\n +---------------------------------------------------------------------------------------------------------+\n | Mode | Mode | Angles number | Currents | Energy windows | Energy windows |\n | Number | Name | [deg] | | Protons | Electrons |\n |-----------------|----------------|------------------|-----------|------------------|--------------------| \n | 2 | Tracking (TMS) | eight: 11.25 centered on Sun-spacecraft line; six: 45 for remainder of spin | A+B and A | 8* | 4 |\n | 3 | Acquisition (AQM | same as TMS | same as TMS | 24 | 21 |\n | 1 | Non-tracking (NTMS) | eight, 45 | A+B only | 24 | 21 |\n +---------------------------------------------------------------------------------------------------------+\n\n *Selected so that the peak flux energy step of the prior distribution is the 3rd step of this measurement.\n\n Note that the mode names are historical and confusing: the NTMS mode has the greatest sensitivity because \nof the 45 degree angular sectors and hence longer integration times, but all the energy windows won't fit into the \nworking side of our on board memory. So all the parameters will be in modes 2 or 3. In order to reduce the time \nbetween spectra, in the TMS mode the eight lowest electron energy windows are covered using four sets of two windows \nof increasing energy; those eight electron windows are thus covered in a sequence of four TM spectra.", "ValidMin": "1", "ValidMax": "8", "FillValue": "9", "Support": { "SupportQuantity": "Other" } }, { "Name": "Spacecraft Position GSE", "ParameterKey": "SC_Pos_GSE", "Description": "Spacecraft position in GSE coordinates", "Units": "Re", "UnitsConversion": "6.378e6>m", "CoordinateSystem": { "CoordinateRepresentation": "Cartesian", "CoordinateSystemName": "GSE" }, "Structure": { "Size": "3", "Element": [ { "Name": "Xgse", "Qualifier": "Component.I", "Index": "1" }, { "Name": "Ygse", "Qualifier": "Component.J", "Index": "2" }, { "Name": "Zgse", "Qualifier": "Component.K", "Index": "3" } ] }, "ValidMin": "-50.0", "ValidMax": "50.0", "FillValue": "9999.0", "Support": { "Qualifier": "Vector", "SupportQuantity": "Positional" } }, { "Name": "Spacecraft Position Y-component GSM", "ParameterKey": "ygsm", "Description": "Spacecraft position Y-component in GSM coordinates", "Units": "Re", "UnitsConversion": "6.378e6>m", "CoordinateSystem": { "CoordinateRepresentation": "Cartesian", "CoordinateSystemName": "GSM" }, "ValidMin": "-50.0", "ValidMax": "50.0", "FillValue": "9999.0", "Support": { "Qualifier": "Component.J", "SupportQuantity": "Positional" } }, { "Name": "Spacecraft Position Z-component GSM", "ParameterKey": "zgsm", "Description": "Spacecraft position Z-component in GSM coordinates", "Units": "Re", "UnitsConversion": "6.378e6>m", "CoordinateSystem": { "CoordinateRepresentation": "Cartesian", "CoordinateSystemName": "GSM" }, "ValidMin": "-50.0", "ValidMax": "50.0", "FillValue": "9999.0", "Support": { "Qualifier": "Component.K", "SupportQuantity": "Positional" } }, { "Name": "V fit", "ParameterKey": "V_fit", "Description": "(Better, from fits) Ion Flow Velocity (aberration corrected)", "Caveats": "Effects due to the orbital motion of Earth are removed \nfrom the better (fits) parameters, but not from the moment parameters.", "Units": "km/s", "UnitsConversion": "1e3>m/s", "CoordinateSystem": { "CoordinateRepresentation": "Spherical", "CoordinateSystemName": "GSE" }, "ValidMin": "100.0", "ValidMax": "3000.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Fit", "Magnitude" ], "ParticleQuantity": "FlowVelocity" } }, { "Name": "V moments", "ParameterKey": "V_mom", "Description": "(From moments) Proton Flow Velocity (no aberration \ncorrection)", "Caveats": "Effects due to the orbital motion of Earth are removed \nfrom the better (fits) parameters, but not from the moment parameters.", "Units": "km/s", "UnitsConversion": "1e3>m/s", "CoordinateSystem": { "CoordinateRepresentation": "Spherical", "CoordinateSystemName": "GSE" }, "ValidMin": "100.0", "ValidMax": "3000.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Moment", "Magnitude" ], "ParticleQuantity": "FlowVelocity" } }, { "Name": "Proton V thermal fit", "ParameterKey": "protonV_thermal_fit", "Description": "(Better, from fits) Proton most-probable thermal \nspeed (aberration corrected). Thermal speed is the most probable thermal \nspeed (i.e., the square root of [2kT/m(proton)]). To convert thermal speed \nto temperature in eV, multiply 0.0052 by the square of the thermal speed; \nto convert to temperature [K], multiply the square of the thermal speed by \n60.5.", "Caveats": "Effects due to the orbital motion of Earth are removed \nfrom the better (fits) parameters, but not from the moment parameters.", "Units": "km/s", "UnitsConversion": "1e3>m/s", "ValidMin": "1.0", "ValidMax": "500.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Fit", "Scalar" ], "ParticleQuantity": "ThermalSpeed" } }, { "Name": "Proton V thermal moments", "ParameterKey": "protonV_thermal_mom", "Description": "\n (From moments) Proton most-probable thermal speed (no aberration \ncorrection). Thermal speed is the most probable thermal speed (i.e., the square \nroot of [2kT/m(proton)]). To convert thermal speed to temperature in eV, multiply \n0.0052 by the square of the thermal speed; to convert to temperature [K], multiply \nthe square of the thermal speed by 60.5.", "Caveats": "Effects due to the orbital motion of Earth are removed from \nthe better (fits) parameters, but not from the moment parameters. This is \nprobably the most inaccurate moment parameter, since moments tend to underestimate \nthe temperature in cold distributions.", "Units": "km/s", "UnitsConversion": "1e3>m/s", "ValidMin": "1.0", "ValidMax": "500.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Moment", "Scalar" ], "ParticleQuantity": "ThermalSpeed" } }, { "Name": "Proton density fit", "ParameterKey": "proton_density_fit", "Description": "(Better, from fits) Proton number density", "Units": "cm^-3", "UnitsConversion": "1e6>m^-3", "ValidMin": "0.0", "ValidMax": "100.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Fit", "Scalar" ], "ParticleQuantity": "NumberDensity" } }, { "Name": "Proton density moments", "ParameterKey": "proton_density_mom", "Description": "(From moments) Proton number density", "Units": "cm^-3", "UnitsConversion": "1e6>m^-3", "ValidMin": "0.0", "ValidMax": "100.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Moment", "Scalar" ], "ParticleQuantity": "NumberDensity" } }, { "Name": "E/W flow angle best", "ParameterKey": "EW_flowangle_best", "Description": "(Best, from fits) Proton East/West flow angle \n(aberration corrected). Azimuth is E/W, meaning bulk flow from the East \nor the West side of the Sun respectively. Positive azimuth angle means \nflow from the West.", "Caveats": "Effects due to the orbital motion of Earth are removed \nfrom the better (fits) parameters, but not from the moment parameters.", "Units": "deg", "CoordinateSystem": { "CoordinateRepresentation": "Spherical", "CoordinateSystemName": "GSE" }, "ValidMin": "-45.0", "ValidMax": "45.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Fit", "DirectionAngle.AzimuthAngle" ], "ParticleQuantity": "FlowVelocity" } }, { "Name": "E/W flow angle moments", "ParameterKey": "EW_flowangle_mom", "Description": "(From moments) Proton East/West flow angle (no \naberration correction). Azimuth is E/W, meaning bulk flow from the East \nor the West side of the Sun respectively. Positive azimuth angle means \nflow from the West.", "Caveats": "Effects due to the orbital motion of Earth are removed \nfrom the better (fits) parameters, but not from the moment parameters.", "Units": "deg", "CoordinateSystem": { "CoordinateRepresentation": "Spherical", "CoordinateSystemName": "GSE" }, "ValidMin": "-45.0", "ValidMax": "45.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Moment", "DirectionAngle.AzimuthAngle" ], "ParticleQuantity": "FlowVelocity" } }, { "Name": "Flow elevation threshsp", "ParameterKey": "Flow_elevation_threshsp", "Description": "(Better, from fits) Proton flow elevation angle \n(aberration corrected) from North or South of the spacecraft spin plane \n(almost identical to the plane of the ecliptic).Positive elevation angle \nmeans flow from the South. Threshsp values are determined from currents \ngreater than a threshold value, below which we are not confident about \nthe contribution of noise.", "Caveats": "Effects due to the orbital motion of Earth are removed \nfrom the better (fits) parameters, but not from the moment parameters.", "Units": "deg", "CoordinateSystem": { "CoordinateRepresentation": "Spherical", "CoordinateSystemName": "GSE" }, "ValidMin": "-45.0", "ValidMax": "45.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Fit", "DirectionAngle.ElevationAngle" ], "ParticleQuantity": "FlowVelocity" } }, { "Name": "Flow elevation thresh", "ParameterKey": "Flow_elevation_thresh", "Description": "(From moments) Proton flow elevation angle (no \naberration correction) from North or South of the spacecraft spin plane \n(almost identical to the plane of the ecliptic).Positive elevation angle \nmeans flow from the South. Thresh values are determined from all \ncurrents.", "Caveats": "Effects due to the orbital motion of Earth are \nremoved from the better (fits) parameters, but not from the moment \nparameters.", "Units": "deg", "CoordinateSystem": { "CoordinateRepresentation": "Spherical", "CoordinateSystemName": "GSE" }, "ValidMin": "-45.0", "ValidMax": "45.0", "FillValue": "9999.0", "Particle": { "ParticleType": [ "Proton", "Ion" ], "Qualifier": [ "Moment", "DirectionAngle.ElevationAngle" ], "ParticleQuantity": "FlowVelocity" } } ] } } }