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Wind Solar Wind Experiment (SWE) Thermal Plamsa Moments, Key Parameter (K0), 99 s Data

Metadata Updated: November 14, 2025

Wind SWE Key Parameter data: proton density, thermal speed, flow velocity vectors, and spacecraft position vectors. Various versions differ slightly from each other. The version at MIT has flow velocity vectors experessed bby using Geocentric Solar Ecliptic, GSE, Cartesian and spherical representations and GSE Cartesian position vectors. The version available via nssdcftp and FTPBrowser has temperature instead of thermal speed and has no flow direction angles. The CDAWeb version has flow velocity and spacecraft position vectors in both GSE and Geocentric Solar Magnetospheric, GSM, coordinates, flow dynamic pressure, NmV^2, and velocity and density quality flags. The data were progressively despiked in passing from CDAWeb to MIT to nssdcftp/FTPBrowser.Use of the Quality Variables:Quality flags are set in the analysis program that generates the KP data. Previous descriptions of their meaning were out of date.Good data is indicated by a quality flag equal to 0.The quality flags for each parameter are given as integers 4 bytes long, integer4.The individual bits for each quality value are set or cleared in the analysis code by adding or subtracting a power of 2 as follows. To set the first bit, add 1, the second bit, add 2, the third bit, add 4, the fourth bit, add 8, and so on. See the table below.+------------------------------------------------------------------------------------------------------------------------------+| Bit | Set Value | MEANING ||------------------------------------------------------------------------------------------------------------------------------|| 1 | 1 | Three point parabolic fits to proton peaks were not attempted. || 2 | 2 | Non-linear least squares fit was not attempted. || 3 | 4 | Three point parabolic fits to proton peaks failed. || 4 | 8 | Non-linear least squares fit failed. || 5 | 16 | Alpha parameters not valid since the non-linear least squares fit was done for protons only. || | | Not enough good energy channels to do simultaneous alpha fit. This value applies to iqual_core(5) only. || 6 | 32 | Analysis code unable to get good value for spin period. || 7 | 64 | SWE instrument in mode 1, calibration state mode. Key parameters are produced in mode 1, science mode. || 8 | 128 | Three point fits done for cup 1 only. Split collector ratio of currents used to get the north/south angle. || | | Either cup 2 turned off, or cup 2 densities were low indicating noise associated with vibration. || 9 | 256 | Fewer than ten fc_blocks in spectrum. Analysis skipped. || 10 | 512 | Alpha particle non-linear fit produced values of density and thermal speed that do not seem reasonable. || 11 | 1024 | Three point parabolic fits to proton peaks done for cup 2 only. Probably Cup 1 is turned off. || | | The ratio of currents on split collectors used to get north/south angle. || 12 | 2048 | Single width windows. Delta E over E 6.5% instead of the default 13%. || 13 | 4096 | Tracking mode operation. || 14 | 8192 | Limited tracking mode scan, not a full scan. |+------------------------------------------------------------------------------------------------------------------------------+Particular flag settings:+-------------------------------------------------------------------------------------------+| Flag Value | Meaning ||-------------------------------------------------------------------------------------------|| 4098 | Tracking mode operation is full scan (4096) and No non-linear fits (2) || 14338 | Tracking mode operation is full scan (4096) and Limited tracking mode (8192) |+-------------------------------------------------------------------------------------------+Comments: Note that in bit 4 of the quality flag the non-linear fit may be reported as good for protons and, at the same time, not good for alphas. Non-linear fits are not done for Key Parameters, KPs, but those parameter values are excellent and should be used to do science. Non-linear fits are available are available in this data product, but they have problems which suggests strongly that the KP parameters should be used, see the paper by Kasper et al., Physics-based tests to identify the accuracy of solar wind ion measurements: A case study with the Wind Faraday Cups, J. Geophys. Res., 111, A03105, DOI: 101029/2005JA011442.* Note that all quality flag values that are even numbers are for data values when non-linear fits were not attempted.For the complete guide to the quality flag values see https://cdaweb.gsfc.nasa.gov/wind_swe_quality.html.Note that this SPASE Numerical Description only describes the MESSENGER Magnetometer data stored in Common Data Files. Other links to Wind SWE data in non CDF format are listed in the following table:+--------------------------------------------------------------------------------------------------------------------------------------------+| SPASE Repository Resource ID | Data Source | Data Access URL ||--------------------------------------------------------------------------------------------------------------------------------------------|| SMWG/Repository/MIT_CSR | ASCII via ftp from MIT | ftp://space.mit.edu/pub/plasma/wind/kp_files/ || SMWG/Repository/NASA/GSFC/SPDF | ASCII via ftps from SPDF | ftps://spdf.gsfc.nasa.gov/pub/data/wind/swe/ascii/swe_kp_unspike/ || SMWG/Repository/NASA/GSFC/SPDF | ASCII via https from SPDF | https://spdf.gsfc.nasa.gov/pub/data/wind/swe/ascii/swe_kp_unspike/ || SMWG/Repository/NASA/GSFC/SPDF | Subset, plot and list via FTPBrowser | https://omniweb.gsfc.nasa.gov/ftpbrowser/wind_swe_kp.html |+--------------------------------------------------------------------------------------------------------------------------------------------+

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Created Date April 11, 2025
Metadata Updated Date November 14, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date November 14, 2025
Publisher NASA Space Physics Data Facility (SPDF) Data Services
Maintainer
Identifier https://doi.org/10.48322/3zky-gy15
Data Last Modified 2025-09-10
Category Heliophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 79c3179d-666c-4bbc-a245-ecc4113ccc3d
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://doi.org/10.48322/3zky-gy15
Program Code 026:000
Source Datajson Identifier True
Source Hash 4039809e67ae5b2f3019607e2a6e5bd7c04dc9578552ae59aa519847b57b2c53
Source Schema Version 1.1
Temporal 1994-11-01/2019-01-18

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