File Naming Format: psp_swp_spc_l2i_yyyymmdd_v01.cdf
Solar Probe Cup, SPC, charge flux distributions comprise electrical current as a function of time and energy-per-charge, with appropriate instrument response elements considered and calibrations applied. This data product contains measurements of ion flux as a function of energy organized into spectra. The SPC instrument measures one-dimensional distributions with a wide field of view. Please refer to the instrument paper for details.
This data set covers all periods for which the instrument was turned on and taking data in the solar wind in ion mode. This includes maneuvers affecting the spacecraft attitude and orientation.
The MODE_FLAG variable contains information about the type of spectrum being measured. "Ion Full Scan" spectra are marked with MODE_FLAG.DAT = 1. These spectra comprise a broad energy range typically with lower signal-to-noise than the more frequent "Ion Peak Tracking" spectra, which are marked with MODE_FLAG.DAT equal to zero. In the most frequent operating mode, ion full scans are executed about once every 30 s or whenever the peak signal from the solar wind is poorly defined.
Data quality is very good for the duration of the encounter. The solar wind flow was within the optimal field of view for the SPC instrument for nearly the entire encounter. See the data flags for specific exceptions. As with all encounters, signal-to-noise is higher during ingress than egress, which is reflected in the typically smaller uncertainties and less frequent "primary peak low signal" flag events.
Measurements recorded during cruise phase are not all transmitted to Earth. The typical return is one spectrum out of every 32.
Due to an erroneous setting in the operating mode for this encounter, ion full scan spectra and certain spectra immediately following ion full scans are of reduced quality. In the affected full scan spectra, the energy steps over an initial portion of the measurement spectra have zero width, i.e. the Level 2 ion variables MV_LO.DAT = MV_HI.DAT, and the corresponding measurements are purely noise. In some cases, this results in a poor determination of the proton "primary peak" energy, which renders additional subsequent full scans that follow subject to the same incompleteness. In other cases, the energy range for the subsequent "ion peak tracking mode" scan is not ideal. The affected Level 3 ion measurements have been flagged with DQF.DAT[22]=1, which stands for "energy ranging/peak tracking error" and/or set to fill. The operating mode has been revised such that future encounters will not be so affected.
As part of the development of collaboration with the broader Heliophysics community, the mission has drafted a "Rules of the Road" to govern how PSP instrument data are to be used.
Version:2.3.1
File Naming Format: psp_swp_spc_l2i_yyyymmdd_v01.cdf
Solar Probe Cup, SPC, charge flux distributions comprise electrical current as a function of time and energy-per-charge, with appropriate instrument response elements considered and calibrations applied. This data product contains measurements of ion flux as a function of energy organized into spectra. The SPC instrument measures one-dimensional distributions with a wide field of view. Please refer to the instrument paper for details.
This data set covers all periods for which the instrument was turned on and taking data in the solar wind in ion mode. This includes maneuvers affecting the spacecraft attitude and orientation.
The MODE_FLAG variable contains information about the type of spectrum being measured. "Ion Full Scan" spectra are marked with MODE_FLAG.DAT = 1. These spectra comprise a broad energy range typically with lower signal-to-noise than the more frequent "Ion Peak Tracking" spectra, which are marked with MODE_FLAG.DAT equal to zero. In the most frequent operating mode, ion full scans are executed about once every 30 s or whenever the peak signal from the solar wind is poorly defined.
Data quality is very good for the duration of the encounter. The solar wind flow was within the optimal field of view for the SPC instrument for nearly the entire encounter. See the data flags for specific exceptions. As with all encounters, signal-to-noise is higher during ingress than egress, which is reflected in the typically smaller uncertainties and less frequent "primary peak low signal" flag events.
Measurements recorded during cruise phase are not all transmitted to Earth. The typical return is one spectrum out of every 32.
Due to an erroneous setting in the operating mode for this encounter, ion full scan spectra and certain spectra immediately following ion full scans are of reduced quality. In the affected full scan spectra, the energy steps over an initial portion of the measurement spectra have zero width, i.e. the Level 2 ion variables MV_LO.DAT = MV_HI.DAT, and the corresponding measurements are purely noise. In some cases, this results in a poor determination of the proton "primary peak" energy, which renders additional subsequent full scans that follow subject to the same incompleteness. In other cases, the energy range for the subsequent "ion peak tracking mode" scan is not ideal. The affected Level 3 ion measurements have been flagged with DQF.DAT[22]=1, which stands for "energy ranging/peak tracking error" and/or set to fill. The operating mode has been revised such that future encounters will not be so affected.
As part of the development of collaboration with the broader Heliophysics community, the mission has drafted a "Rules of the Road" to govern how PSP instrument data are to be used.
| Role | Person | |
|---|---|---|
| 1. | PrincipalInvestigator | spase://SMWG/Person/Justin.C.Kasper |
| 2. | MetadataContact | spase://SMWG/Person/Robert.M.Candey |
| 3. | MetadataContact | spase://SMWG/Person/Lee.Frost.Bargatze |
Parker Solar Probe, PSP, SWEAP Instrument Suite Description: Kasper, J.C., Abiad, R., Austin, G. et al., Solar Wind Electrons Alphas and Protons (SWEAP) Investigation: Design of the Solar Wind and Coronal Plasma Instrument Suite for Solar Probe Plus, Space Scii. Rev., 204, 131–186 (2016)
Parker Solar Probe, PSP, SWEAP home page, Smithsonian Astrophysical Observatory
Parker Solar Probe, PSP, SWEAP Data Access web site, Smithsonian Astrophysical Observatory
Access to Data in CDF Format via ftp from SPDF
Access to Data in CDF Format via http from SPDF
Access to ASCII, CDF, and Plots via NASA/GSFC CDAWeb
Epoch Time Tags, TT2000, Nanoseconds since J2000 at Midpoint of the Integration
Measurement Time: the time of flux measurement from the Epoch time at the beginning of spectrum
Solar Probe Cup, SPC, Modulator Voltage Index, mv_index
Solar Probe Cup, SPC, Modulator Voltage, hi, the upper bound of the oscillating potential barrier
Solar Probe Cup, SPC, Modulator Voltage, hi, the upper bound of the oscillating potential barrier, measurement uncertainty
Solar Probe Cup, SPC, Modulator Voltage, lo, the lower bound of the oscillating potential barrier
Solar Probe Cup, SPC, Modulator Voltage, lo, the lower bound of the oscillating potential barrier, measurement uncertainty
Solar Probe Cup, SPC, Sensor Plate A Current
Solar Probe Cup, SPC, Sensor Plate B Current
Solar Probe Cup, SPC, Sensor Plate C Current
Solar Probe Cup, SPC, Sensor Plate D Current
Solar Probe Cup, SPC, Sensor Plate A Current, measurement uncertainty
Solar Probe Cup, SPC, Sensor Plate B Current, measurement uncertainty
Solar Probe Cup, SPC, Sensor Plate C Current, measurement uncertainty
Solar Probe Cup, SPC, Sensor Plate D Current, measurement uncertainty
Solar Probe Cup, SCP, Bulk Flow Angles: Azimuth and Elevation: the angles associated with the mean flow into the cup, SPC coordinates
Solar Probe Cup, SPC, Bulk Flow Azimuth and Elevation Angles, uncertainties in the angle of flow into the cup in SPC coordinates
Solar Probe Cup, SPC, Charged Flux Density: This variable is a measure of the charge flux density of the solar wind measured over the energy range defined by the modulator voltage pair. The calibrated effective area of the SPC instrument has been taken into account. This measured charge flux density is equivalent to the total charge crossing a surface oriented perpendular to Z-axis in the Spacecraft, SC, reference frame per unit area per unit time due to charge carriers having energy-per-charge in the range between the modulator voltage low and high, MV_LO and MV_HI, settings. This quantity is estimated by using the linear, cold plasma approximation for the mean flow angle of the solar wind into the sensor. It does not account for spreading of the beam in the instrument, which may be significant. Please refer to Case et al. 2019 and/or consult the instrument team regarding systematics in accuracy and precision for this quantity. Appendix 3.1 provides a walk through for estimating the reduced distribution function from this variable.
Solar Probe Cup, SPC, Differential Charged Flux Density, uncertainty
Solar Probe Cup, SPC, Operating Mode Flag: signifies the SPC operating mode at the time of measurement.