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1) Cluster Samba WBD High Time Resolution Dynamic Spectrogram Plot maxmize
Resource ID:spase://VWO/DisplayData/Cluster-Samba/WBD/DS.GIF.PT30S
Start:2001-02-03 05:26:00 Observatory:Cluster FM7 (Samba) Cadence:
Stop:2016-05-19 13:23:47 Instrument:Wide Band Data (WBD) Resource:DisplayData
This dataset contains 30 s duration survey spectrogram plots from the WBD instrument on the Cluster spacecraft. The spectrograms are created by 1024 point FFTs and plotted with frequency on the vertical axis, increasing time on the horizontal, and color indicating power spectral density, in relative dB. The AC electric field data are obtained by using one of the two 88m spin plane electric field antennas of the EFW instrument as a sensor. The AC magnetic field data are obtained by using one of the two search coil magnetometers (one in the spin plane, the other along the spin axis) of the STAFF instrument as a sensor. The WBD data are obtained in one of three filter bandwidth modes: (1) 9.5 kHz, (2) 19 kHz, or (3) 77 kHz. The minimum frequency of each of these three frequency bands can be shifted up (converted) from the default 0 kHz base frequency by 125.454, 250.908 or 501.816 kHz. The time resolution of the data shown in the plots is determined from the WBD instrument mode. The highest time resolution data are sampled at 4.6 microseconds in the time domain, 4.7 milliseconds in the frequency domain (generally the 77 kHz bandwidth mode). The lowest time resolution data are sampled at 36.5 microseconds in the time domain, 37.3 milliseconds in the frequency domain (generally the 9.5 kHz bandwidth mode). Above the spectrogram plot are a line plot panel, followed by four status lines. The line plot panel at the top provides the gain state (0 to 75 dB, in 5 dB steps) of the instrument. The four status lines provide the following information according to the color code in the upper right corner: Data mode - whether from DSN mode (real time telemetry), or from BM2 mode (recorded onboard in Burst Mode 2) as digitally filtered or duty cycled. Antenna - the electric field (Ey or Ez) or the magnetic field (Bx or By) antenna used. Resolution - the data digitization level, which can be 1 bit, 4 bit or 8 bit. Translation - the translation from base frequency of 0 kHz. In the lower right-hand corner are the ephemeris values applicable to the start time of the plot. At the middle right-hand side are given the date and start time of the plot as well as the spacecraft number. The University of Iowa repository maintains two types of high time resolution spectrogram plots in GIF format: a ten minute (PT10M Display Cadence) and a 30 second time span (PT30S Display Cadence). Both types of files provide information on WBD gain and operational mode, the spectral data from one spacecraft, the start date and time and ephemeris data. Overview spectrograms are also available. The availability of these files depends on times of DSN and Pansak Ves ground station telemetry downlinks. A list of the status of the WBD instrument on each spacecraft, the telemetry time spans, operating modes and other details are available under Science Data Availability on the University of Iowa Cluster WBD web site at http://www-pw.physics.uiowa.edu/cluster/ and through the documentation section of the Cluster Active Archive (http://caa.estec.esa.int/caa). Details on Cluster WBD Interpretation Issues can be found at http://www-pw.physics.uiowa.edu/cluster/interpretation_issues/interpretation.html For further details on the Cluster WBD data products see Pickett, J.S., et al., "Cluster Wideband Data Products in the Cluster Active Archive" in _The Cluster Active Archive_, 2010, Springer-Verlag, pp 169-183.

2) Cluster 3 Wideband Data Plasma Wave Receiver/High Time Resolution Waveform Data maxmize
Resource ID:spase://VWO/NumericalData/Cluster-Samba/WBD/PT0.0000046S
Start:2001-02-03 05:26:00 Observatory:Cluster FM7 (Samba) Cadence:0.0000046 seconds
Stop:2016-05-19 13:23:49 Instrument:Wide Band Data (WBD) Resource:NumericalData
The following description applies to the Wideband Data (WBD) Plasma Wave Receivers on all four Cluster satellites, each satellite being uniquely identified by its number (1 through 4) or its given name (Rumba, Salsa, Samba, Tango, respectively). High time resolution calibrated waveform data sampled in one of 3 frequency bands in the range 0-577 kHz along one axis using either an electric field antenna or a magnetic search coil sensor. The dataset also includes instrument mode, data quality and the angles required to orient the measurement with respect to the magnetic field and to the GSE coordinate system. The AC electric field data are obtained by using one of the two 88m spin plane electric field antennas of the EFW (Electric Fields and Waves) instrument as a sensor. The AC magnetic field data are obtained by using one of the two search coil magnetometers (one in the spin plane, the other along the spin axis) of the STAFF (Spatio-Temporal Analysis of Field Fluctuations) instrument as a sensor. The WBD data are obtained in one of three filter bandwidth modes: (1) 9.5 kHz, (2) 19 kHz, or (3) 77 kHz. The minimum frequency of each of these three frequency bands can be shifted up (converted) from the default 0 kHz base frequency by 125.454, 250.908 or 501.816 kHz. The time resolution of the data shown in the plots is determined from the WBD instrument mode. The highest time resolution data (generally the 77 kHz bandwidth mode) are sampled at 4.6 microseconds in the time domain (~4.7 milliseconds in the frequency domain using a standard 1024 point FFT). The lowest time resolution data (generally the 9.5 kHz bandwidth mode) are sampled at 36.5 microseconds in the time domain (~37.3 milliseconds in the frequency domain using a standard 1024 point FFT). The availability of these files depends on times of DSN and Panska Ves ground station telemetry downlinks. A list of the status of the WBD instrument on each spacecraft, the telemetry time spans, operating modes and other details are available under Science Data Availability on the University of Iowa Cluster WBD web site at http://www- pw.physics.uiowa.edu/cluster/ and through the documentation section of the Cluster Active Archive (CAA) (http://caa.estec.esa.int/caa). Details on Cluster WBD Interpretation Issues and Caveats can be found at http://www- pw.physics.uiowa.edu/cluster/ by clicking on the links next to the Caution symbol in the listing on the left side of the web site. These documents are also available from the Documentation section of the CAA website. For further details on the Cluster WBD data products see Pickett, J.S., et al., "Cluster Wideband Data Products in the Cluster Active Archive" in _The Cluster Active Archive_, 2010, Springer-Verlag, pp 169-183, and the Cluster WBD User Guide archived at the CAA website in the Documentation section. ... CALIBRATION: ... The procedure used in computing the calibrated Electric Field and Magnetic Field values found in this file can be obtained from the Cluster WBD Calibration Report archived at the CAA website in the Documentation section. Because the calibration was applied in the time domain using simple equations the raw counts actually measured by the WBD instrument can be obtained by using these equations and solving for 'Raw Counts', keeping in mind that this number is an Integer ranging from 0 to 255. Since DC offset is a real number, the resultant when solving for raw counts will need to be converted to the nearest whole number. A sample IDL routine for reverse calibrating to obtain 'Raw Counts' is provided in the WBD Calibration Report archived at the CAA. ... CONVERSION TO FREQUENCY DOMAIN: ... In order to convert the WBD data to the frequency domain via an FFT, the following steps need to be carried out: 1) If Electric Field, first divide calibrated data values by 1000 to get V/m; 2) Apply window of preference, if any (such as Hann, etc.); 3) Divide data values by sqrt(2) to get back to the rms domain; 4) perform FFT (see Bandwidth variable notes for non-continuous modes and/or the WBD User Guide archived at the CAA); 5) divide by the noise bandwidth, which is equal to the sampling frequency divided by the FFT size (see table below for appropriate sampling frequency); 6) multiply by the appropriate constant for the window used, if any. These steps are more fully explained in the WBD Calibration Report archived at the CAA.... +--------------------------+ | Bandwidth | Sample Rate | |-----------|--------------| | 9.5 kHz | 27.443 kHz | | 19 kHz | 54.886 kHz | | 77 kHz | 219.544 kHz | +--------------------------+ COORDINATE SYSTEM USED: ... One axis measurements made in the Antenna Coordinate System, i.e., if electric field measurement, it will either be Ey or Ez, both of which are in the spin plane of the spacecraft, and if magnetic field measurement, it will either be Bx, along the spin axis, or By, in spin plane. The user of WBD data should refer to the WBD User Guide, archived at the CAA, Section 5.4.1 and Figure 5.3 for a description of the three orientation angles provided in these files. Since WBD measurements are made along one axis only, these three angles provide the only means for orienting the WBD measurements with respect to a geocentric coordinate system and to the magnetic field direction ...

3) Cluster 3 WHISPER Natural Electric Power Spectral Density maxmize
Resource ID:spase://VWO/NumericalData/Cluster-Samba/WHISPER/PT2S
Start:2000-08-16 12:39:00 Observatory:Cluster FM7 (Samba) Cadence:2.14 seconds
Stop:2016-05-19 13:23:49 Instrument:Waves of HF and Sounder for Probing Electron Density by Relaxation (WHISPER) Resource:NumericalData
The Waves of HIgh frequency and Sounder for Probing of Electron density by Relaxation (WHISPER) performs the measurement of the electron density on the four satellites of the Cluster project. The two main purposes of the WHISPER experiment are to record the natural waves and to make a diagnostic of the electron density using the sounding technique. The various working modes and the fourier transforms calculated on board provide a good frequency resolution obtained in the bandwidth 2-83 kHz. Onboard data compression by the Digital Wave Processing (DWP) intrument allows a good dynamic and level resolution of the electric signal amplitude.

4) Cluster 3 WHISPER Active Electric Power Spectral Density maxmize
Resource ID:spase://VWO/NumericalData/Cluster-Samba/WHISPER/PT52S
Start:2000-08-16 12:39:00 Observatory:Cluster FM7 (Samba) Cadence:52 seconds
Stop:2016-05-19 13:23:49 Instrument:Waves of HF and Sounder for Probing Electron Density by Relaxation (WHISPER) Resource:NumericalData
The Waves of HIgh frequency and Sounder for Probing of Electron density by Relaxation (WHISPER) performs the measurement of the electron density on the four satellites of the Cluster project. The two main purposes of the WHISPER experiment are to record the natural waves and to make a diagnostic of the electron density using the sounding technique. The various working modes and the fourier transforms calculated on board provide a good frequency resolution obtained in the bandwidth 2-83 kHz. Onboard data compression by the Digital Wave Processing (DWP) intrument allows a good dynamic and level resolution of the electric signal amplitude.

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