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WIND

Two Columns



Wind Instrument and Data Documentation



Wind Magnetic Field Investigation (MFI)


  • Instrument Description
    • The Wind Magnetic Field Investigation (MFI) is composed of two fluxgate magnetometers located at 2/3 of the way out and at the end of a 12 m boom. The instrument measures DC vector magnetic fields up to a time resolution of 22 or 11 vectors/sec depending on the telemetry mode of the spacecraft. A complete description of the instrument can be found in the Space Science Reviews article by Lepping et al.. Additional information can be found on the Instrument Web Page.

  • Calibration and Data Product Documentation
    • The primary calibration method employed in generating the MFI data products is described by Farrell et al. [1995] and Kepko et al., [1996].

    • The calibration method of the spin axis component of the magnetic field is described by Leinweber, H. K. et al., Meas. Sci. Technol., 19, 055104, 2008.

    • The largest source of uncertainty in the MFI data is the inherent rms noise due to averaging. The vector rms variation is computed for all data points and for all time averages from the raw telemetered data and is included in the publicly distributed data files.

    • Proper calibration of the magnetic field data requires long duration measurements. In order to provide data at the earliest possible time, calibration takes place in three stages resulting in version 3, 4, and 5 data products. The processes used for each step are described in version description document..

    • Some additional information about the MFI instrument can be found in Koval & Szabo 2008.

Wind Solar Wind Experiment (SWE) Faraday Cup - Ion Data


  • Instrument Description
  • Calibration and Data Product Documentation
    • A detailed description of the algorithms and procedures used to generate the Faraday Cup data products is provided in the PhD Thesis of J. Kasper.

    • Detailed, point-by-point error analysis is included in each data file.

    • The systematic uncertainties of the measurements, calibrated against other Wind instruments and based on basic physical principles, are discussed in Kasper et al. [2006].

    • Additional instrument details can be found in the recent review paper Verscharen et al. [2019], and the arXiv version can be found at 1902.03448.

Wind Solar Wind Experiment (SWE) Electron Data


  • Instrument Description
    • The SWE electron sub-system consists of two electrostatic analyzers, the vector spectrometer (VEIS) and the Strahl spectrometer. They were both designed to measure the solar wind electron distribution function. The original configuration of the detectors are described by Ogilvie et al. [1995].

    • After the failure of the high voltage power supply of VEIS in 2001, the Strahl detector was reconfigured to recover most of the measurement capabilities. An updated version of the SWE Space Science Reviews article reflecting the changes is also available.

    • The history and description of the SWE electron instruments can also be found at the instrument Web site.

  • Calibration and Data Product Documentation
    • The algorithms used to generate the electron pitch angle and strahl data is described in an internal memo.

    • Additional data product and calibration algorithm information can be found in the VEIS and Strahl Data Documentation.

    • Complete description of the various electron data products can be found at the instrument Web site.

    • Extensive documentation for each data product is also provided in the headers of the CDF files.

Wind 3D Plasma Analyzer


  • Instrument Description
    • The Wind 3DP instrument consists of six different sensors. There are two electron (EESA) and two ion (PESA) electrostatic analyzers with different geometrical factors and field-of-views covering the energy range from 3 eV to 30 keV. There are also a pair of solid state telescopes (SST) that measure electrons with energies up to 400 keV and protons with energies up to 6 MeV. The instrument is fully described by Lin et al. [1995].

    • Some more documentation of the instrument is also available from the 3DP Home Page.

  • Calibration and Data Product Documentation
    • Metadata for the 3DP data products are available from the Virtual Heliospheric Observatory (VHO).

    • Data product description is included in the header of each CDF data file.

    • Some additional information about the 3DP instrument is found in Wind 3DP Notes and in Wilson 2010 Dissertation. Further details about reading, calibrating, and analyzing the level zero files can be found at the open-source software library written by Lynn B. Wilson III at UMN 3DP.

    • More nuanced details about the 3DP electron electrostatic analyzers (ESAs) can be found in the (open access) publication Wilson et al. [2019a] with additional supplemental notes and data product at Wilson et al. [2019b]. Similar Wind instruments used in combination with the 3DP ESAs are detailed in another (open access) publication Wilson et al. [2018].

Wind SMS Suprathermal Particle Data


  • Instrument Description
    • The Wind SMS instrument suite is composed of three separate instruments. The SupraThermal Ion Composition Spectrometer (STICS) determines the mass, mass per charge, and energy for ions in the energy range of 6-230 keV/e. The high resolution mass spectrometer (MASS) determines elemental and isotopic abundances from 0.5 to 12 keV/e. Finally, The Solar Wind Ion Composition Spectrometer (SWICS) determines mass, charge, and energy for ions in the energy range of 0.5 to 30 keV/e. The SWICS "stop" MCP experienced a failure resulting in reduced capabilities for this instrument. These instruments are fully described by Gloeckler et al. [1995].

  • Instrument Highlights
    • A recent list of scientific highlights was generated for the SMS instrument in an annual grant report that has useful documentation and details about the instrument.

  • Calibration and Data Product Documentation
    • The methodology of instrument calibration and data product generation is detailed in Ghielmetti et al. [1983].

    • Detailed discussion of the STICS instrument response function and calibration results are provided in the PhD Thesis of K. Chotoo.

    • A new software system has been developed which automates many data analysis functions previously done manually. This system first simultaneously assigns events to specific ion species, removing any overlap and using the statistical properties of the measurements to maximum advantage. It then uses these assigned events to construct phase space density distribution functions and corrects these for the effects of instrument efficiency and sampling geometry. Finally, it outputs these distribution functions, error estimates, and count rates for each ion along with many intermediate products that facilitate detailed analysis. The release notes of these data products contain further details.

    • The newest data products were updated in mid-2022 and the documentation can be found at Revision D Release Notes.

    • Some additional documentation for STICS can be found in Jacob Gruesbeck's dissertation.

    • Some additional documentation for MASS can be found in George C. Ho's dissertation.

Wind EPACT High Energy Particle Data


  • Instrument Description
    • The Energetic Particles: Acceleration, Composition and Transport (EPACT) investigation consists of eight telescopes distributed amongst three instrument systems. These systems are the Suprathermal Energetic Particle telescope (STEP), Low Energy Matrix Telescope (LEMT), and ELectron-Isotope TElescope (ELITE). The ELITE telescope consists of three subsystems: an ion telescope (IT) and two alpha-proton-electron telescopes (APE-A and APE-B). Although APE-A and IT failed almost immediately after the spacecraft launched, APE-B still manages to measure 5 and 20 MeV protons. The LEMT and STEP telescopes, covering energies in the 1-10 MeV/nuc and 0.02-1.0 MeV/nuc range, respectively, are nominal and continue to provide valuable data. These instruments are described in detail by Von Rosenvinge et al. [1995].

    • Further information on the instrument is available on the Instrument Web Page.

  • Calibration and Data Product Documentation
    • The particle detection algorithm is described by Von Rosenvinge et al. [1995].

    • The content of the Omnidirectional Intensity data files is described by the documentation in the data directory.

    • The content of the Sectored Count data files is described in the documentation in the data directory.

    • The content of the Temperature Anisotropy data files is described in the documentation in the data directory.

    • Some additional documentation about the LEMT detector can be found in the book by Don Reames.

    • Some additional documentation about the STEP detector can be found in the papers Filwett et al. [2017] and Filwett et al. [2019].

Wind WAVES Radio and Plasma Waves Data


  • Instrument Description
    • The WAVES experiment on the Wind spacecraft is composed of three orthogonal electric field antenna and three orthogonal search coil magnetometers. The electric fields are measured through five different receivers: Low Frequency FFT receiver called FFT (0.3 Hz to 11 kHz), Thermal Noise Receiver called TNR (4-256 kHz), Radio receiver band 1 called RAD1 (20-1040 kHz), Radio receiver band 2 called RAD2 (1.075-13.825 MHz), and the Time Domain Sampler called TDS. The electric field antenna are dipole antennas with two orthogonal antennas in the spin plane and one spin axis stacer antenna. Calibration found that the effective antenna lengths are roughly 41.1 m, 3.79 m, and 2.17 m for the X, Y, and Z antenna respectively [Note: These are preliminary estimates and may change.]. The orientation of the search coils are aligned with the dipole antennas.

    • The TDS receiver allows one to examine the electromagnetic waves observed by Wind as time series waveform captures. There are two modes of operation, TDS Fast (TDSF) and TDS Slow (TDSS). TDSF returns 2048 data points for two components of the electric field, typically Ex and Ey (i.e. spin plane components), with little to no gain below about 120 Hz. TDSS returns four field vectors with three electric(magnetic) field components and one magnetic(electric) component. The search coils show a gain roll off around 3.3 Hz.

    • The instrument is fully described by Bougeret et al. [1995].

    • Some additional technical information is also available on the Instrument Web Page.

    • Some additional information about the WAVES TDS receiver is found in Wilson 2010 Dissertation.

  • Calibration and Data Product Documentation
    • Some additional information about the WAVES TDS receiver is found in Wind WAVES Notes.

    • The calibration of the TNR receiver that allowed the estimation of electron densities based on the identification of the electron plasma frequency is described by Maksimovich et al. [1998].

    • The documentation for the WAVES 1-minute average data can be found on the Instrument Web Page.

Wind KONUS and TGRS Data


  • Instrument Description
  • The KONUS instrument is fully described by Aptekar et al. [1995].

  • The TGRS instrument is fully described by Owens et al. [1995].

    • KONUS remains a very active partner in the Gamma-ray Coordinates Network (GCN) (work done by Dr. Scott Barthelmy) and the Interplanetary Network (maintained by Dr. Kevin Hurley). Notifications of astrophysical transients are sent worldwide instantly from KONUS, and are of importance in the subsequent positioning of telescopes everywhere. Thus, the instrument remains an active contributor to the astrophysical community.

    • KONUS energy range (now ~20 keV -- 15 MeV) corresponds to the emission of the electrons and ions accelerated in solar flares, and high temporal resolution in the triggered mode allows to study fine structures of hard X-ray solar emission. At the moment KONUS is the only instrument in hard X-ray and soft gamma-ray which observed two full solar cycles. The KONUS-Sun solar flare database (see link below) is unique due to wide energy range, long observational period and the absence of the Earth occultations.

    • KONUS continues to work with other gamma-ray space telescopes like the Swift Mission.

  • Solar Flare Data Product

Additional Information

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