<_Note>Nodes prefixed with a _ are not valid SPASE, but are included for debugging. Values prefixed with a x_ are not valid SPASE but may considered for addition for completeness. 2.6.1 <_MasterURL>https://cdaweb.gsfc.nasa.gov/pub/software/cdawlib/0JSONS/psp_fld_l3_sqtn_rfs_v3v4_00000000_v01.json (from all.xml) <_ResourceID>Source: https://github.com/rweigel/cdawmeta-spase/blob/main/ResourceID.json Parker Solar Probe FIELDS Level 3 Simplified Quasi-Thermal Noise data, using the Radio Frequency Spectrometer spectra when connected to V3V4 dipole antenna <_ResourceName>Source: Master/CDFglobalAttributes/Logical_source_description psp_fld_l3_sqtn_rfs_V3V4 <_AlternateName>Source: Master/CDFglobalAttributes/Logical_source Parker Solar Probe/FIELDS Simplified Quasi-Thermal Noise data (SQTN).The SQTN spectroscopy is a method which allows to deduce the electron density and the core temperature of the plasma surrounding a s/c, by using the power spectra acquired from an electric dipole antenna (see [1] for the PSP case, and references therein).There are two dipoles on the PSP/FIELDS experiment [2] exploitable for the SQTN, named V1V2 and V3V4, which are both connected to the FIELDS Radio Frequency Spectrometer (RFS), see [3].The density is deduced from the plasma frequency (fp) detection algorithm, applied to RFS available spectra, with elimination of questionable detection (or false positive) using QTN theory (see [1]). No fp detection results in filling the data by -1e31 (for all variables provided here). In particular, since we are using 2x2m dipoles on PSP, the fp detection is impossible when the local Debye length is larger than about 5m. On a daily basis, the typical rate of validated detection of fp is more than 90% of the available spectra when PSP is within 0.25 AU of the Sun, but this rate may drop to only 20% at larger distances (0.5 AU being the upper limit used to product this CDF file, which corresponds at most to +/- 15 days around the exact date of the PSP perihelion).When the fp detection is validated, fp errors bars are defined taking into account the RFS_LFR spectral resolution (64 pseudo-logarithmically spaced frequencies in the range from 10 kHz to 1.7 MHz), then refined by using QTN theory, and this finally provides the error bars for the density (electron_density_delta). The electron density is then deduced as the most probable value within the error bars, using again QTN theory.Note the electron density provided here is fully independant of antennas calibrations and floating potential, but not the electron core temperature which is deduced from the QTN level below fp (see [1]), so the core temperature will be certainly more subject to future improvments of this CDF file (see version (see mods attribute).All variables provided here were not subject to post-processing noise filtering nor any interpolation/smoothing of data.The time resolution of the RFS varies with instrument mode, so does the SQTN electron data derived from RFS data. During encounter (when PSP is within 0.25 AU of the Sun), cadence for RFS HFR and LFR spectra is typically about 7 seconds (and about 3.5 seconds during +/- 3 days around the perihelion date from encounter 06). During cruise mode, which is the default mode for operations outside of 0.25 AU, cadence for HFR and LFR spectra is about 56 seconds.References:1. Moncuquet, M., Meyer-Vernet, N., Issautier, K. et al. (2020), Astrophysical Journal Supplement Series, 246:44. https://doi.org/10.3847/1538-4365/ab5a842. Bale, S.D., Goetz, K., Harvey, P.R. et al. Space Sci Rev (2016) 204: 49. https://doi.org/10.1007/s11214-016-0244-53. Pulupa, M., Bale, S. D., Bonnell, J.W. et al. (2017) JGR Space Physics, 122, 2836-2854. https://doi.org/10.1002/2016JA023345 <_Description>Source: Master/CDFglobalAttributes/TEXT In publications, we recommend to add the following sentence in the acknowledgments: "The authors acknowledge LESIA (Laboratoire d Etudes Spatiales et Instrumentation en Astrophysique), Observatoire de PARIS, CNRS (Centre National de la Recherche Scientifique) and TBD " <_Acknowledgement>Source: Master/CDFglobalAttributes/Acknowledgement <_Rights> SPDX Creative Commons Zero v1.0 Universal https://spdx.org/licenses/CC0-1.0.html https://spdx.org/licenses/ https://fields.ssl.berkeley.edu/data/ FIELDS SOC PSP/FIELDS data are available at <_Note>URL also in all.xml. Using master. https://cdpp.eu CDPP PSP/FIELDS data are also available at <_Note>URL also in all.xml. Using master. In_situ electron density and core temperature (SQTN from V3V4 dipole of Parker Solar Probe during Encounter 25) The PSP/FIELDS data provided here are publicly available. We suggest contacting Michel.Moncuquet@obspm.fr (LESIA) when using these data and for any further question. For parents data, see PSP/FIELDS Rules of the Road available at http://fields.ssl.berkeley.edu/rules/ <_Caveats>Source: Master/CDFglobalAttributes/Rules_of_use <_DOI>Source: https://github.com/rweigel/cdawmeta-spase/blob/main/DOI.json <_AccessInformation>Source: https://github.com/rweigel/cdawmeta-spase/blob/main/AccessInformation.json 2021-04-19T00:00:00Z 2026-03-16T23:59:57Z <_TemporalDescription>Generated from all.xml/@timerange_start and all.xml/@timerange_stop <_ObservedRegion>Source: https://github.com/rweigel/cdawmeta-spase/blob/main/ObservedRegion.json <_ProcessingLevel>Processing level is not available in the master file; it should be there instead of, say, https://github.com/rweigel/cdawmeta-spase/blob/main/ProcessingLevel.json spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory HTTPS from SPDF https://cdaweb.gsfc.nasa.gov/pub/data/psp/fields/l3/sqtn_rfs_v3v4 In CDF via HTTP from CDAWeb psp_fld_l3_sqtn_rfs_v3v4_%Y%m%d_%Q.cdf %Y PSP_FLD_L3_SQTN_RFS_V3V4 CDF spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory FTPS from SPDF ftps://cdaweb.gsfc.nasa.gov/pub/data/psp/fields/l3/sqtn_rfs_v3v4 In CDF via HTTP from CDAWeb psp_fld_l3_sqtn_rfs_v3v4_%Y%m%d_%Q.cdf %Y PSP_FLD_L3_SQTN_RFS_V3V4 CDF spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory CDAWeb Web Service https://cdaweb.gsfc.nasa.gov/WebServices/ Instructions for using web services to access this dataset an other other metadata and options for CDAWeb datasets. The ProductKey here corresponds to the query parameter 'dataset' in the tables at the AccessURL in a dataset-related request can be made. PSP_FLD_L3_SQTN_RFS_V3V4 CDF CSV GIF NetCDF PNG PS PDF XML x_Script.IDL x_Script.Python Text.ASCII x_WAV spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory CDAWeb Web Service user interface https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?index=sp_phys&dataset=PSP_FLD_L3_SQTN_RFS_V3V4 PSP_FLD_L3_SQTN_RFS_V3V4 Web service user interface for this product. CDF GIF PDF Text.ASCII x_WAV spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory CDAWeb Python Script https://cdaweb.gsfc.nasa.gov/WS/cdasr/1/dataviews/sp_phys/datasets/PSP_FLD_L3_SQTN_RFS_V3V4/clientLibraryExample/ PSP_FLD_L3_SQTN_RFS_V3V4 Web service that generates a Python script to access this product. x_Script.IDL x_Script.Python spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/SSCWeb. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory 4D Orbit Viewer https://sscweb.gsfc.nasa.gov/4dorbit/?sc=PSP_FLD_L3_SQTN_RFS_V3V4 PSP_FLD_L3_SQTN_RFS_V3V4 Web Service to this product. HTML spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb and the HAPI project. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory CDAWeb HAPI Server https://hapi-server.org/servers/#server=CDAWeb&dataset=PSP_FLD_L3_SQTN_RFS_V3V4 PSP_FLD_L3_SQTN_RFS_V3V4 Web Service to this product using the HAPI interface. CSV JSON Binary spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb and the HAPI project. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory CDAWeb HAPI Script in Multiple Languages https://hapi-server.org/servers/#server=CDAWeb&dataset=PSP_FLD_L3_SQTN_RFS_V3V4&return=script PSP_FLD_L3_SQTN_RFS_V3V4 Web Service user interface that generates scripts in IDL, Javascript, MATLAB, Python, Autoplot, curl, wget to access this product. See https://hapi-server.org/servers/api for the API. x_Script.IDL x_Script.Javascript x_Script.MATLAB x_Script.Python x_Script.Autoplot x_Script.curl x_Script.wget spase://SMWG/Repository/NASA/GSFC/SPDF Online Open SPDF/CDAWeb and the HAPI project. Please also acknowledge the data producer: Stuart D. Bale (bale@ssl.berkeley.edu) at UC Berkeley Space Sciences Laboratory HAPI visualizations https://hapi-server.org/plot/?server=https://cdaweb.gsfc.nasa.gov/hapi&dataset=PSP_FLD_L3_SQTN_RFS_V3V4&format=gallery PSP_FLD_L3_SQTN_RFS_V3V4 Web Service that generates plots. See https://hapi-server.org/plot/ for the API. PNG PDF SVG Parker Solar Probe FIELDS (from all.xml/observatory/description/@short) Simplified Quasi-Thermal Noise from V3V4 dipole (from all.xml/instrument/description/@short) Solar Physics (from Master/CDFglobalAttributes/Discipline) Heliospheric Physics Space Physics (from Master/CDFglobalAttributes/Discipline) Interplanetary Studies (from Master/CDFglobalAttributes/Discipline) PSP_FLD (from Master/CDFglobalAttributes/Source_name) Parker Solar Probe FIELDS (from Master/CDFglobalAttributes/Source_name) L3 (from Master/CDFglobalAttributes/Data_type) Level 3 data, time series (from Master/CDFglobalAttributes/Data_type) SQTN_V3V4 (from all.xml/instrument/@ID) Heliosphere Heliosphere.Inner Heliosphere.NearEarth Sun.Corona Epoch Epoch CATDESC: 'Universal Time in nanoseconds since 01/01/2000'. Notes not in Master CDF: 'The units are the units in CDF files. For other web services, this variable is may be represented as a time string.' ns Scalar Temporal electron_density electron_density Master CDF CATDESC: 'Electron number density'. Master CDF VAR_NOTES: 'The electron density is deduced from the automatic detection of the plasma frequency in RFS spectra with SQTN spectroscopy (see TEXT_global_attributes and VAR_NOTES_density_quality_flag_attributes for more details)'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch.' cm^-3 -1e+31 density_quality_flag density_quality_flag Master CDF CATDESC: 'electron density quality flag, byte'. Master CDF VAR_NOTES: 'The flag mostly indicates the pass/fail of the several processing sequentially applied on each RFS-LFR spectrum to detect the plasma frequency fp and so the electron density. A first algorithm is aimed to detect fp by search of the steepest climb (within the limits of the RFS-LFR spectral resolution), with flag=0 if it fails, flag=1 if pass. Then a second algo checks if the spectrum is QTN-like, and if so refines the fp value (flag=2, majority of cases). In some cases of non-QTN spectra, a third process, based on the possible cutoff at fp of enough strong solar emissions (as type 3 emissions), allows to set an upper limit on fp (flag=3, and corresponding inf_uncertainty set to fillval). Also some QTN-like spectra with very high resonance at fp (instability) are indicated by flag=4. Summary for the density_quality_flag values : 0) no detection, 1,2,4) density validated from QTN criteria, 3) upper limit of density only .'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch.' None 255 electron_core_temperature electron_core_temperature Master CDF CATDESC: 'Electron core temperature'. Master CDF VAR_NOTES: 'The electron core temperature is deduced from the QTN level below fp in RFS spectra with SQTN spectroscopy (see TEXT_global_attributes)'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch.' eV -1e+31 electron_density_delta electron_density_delta Master CDF CATDESC: 'Uncertainty of electron density'. Master CDF VAR_NOTES: 'electron_density - electron_density_delta[0] < electron_density < electron_density + electron_density_delta[1]'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch.' m^-3 -1e+31 2