This PFRC README.txt file was generated on 2023-08-04 by S.A. Cohen A PDF version of this README is available with graphical illustration. ------------------- GENERAL INFORMATION ------------------- Title of Dataset: Data from the Princeton Field Reversal Configuration (PFRC) Experiment Author Information: A. Principal Investigator Contact Information Name: Samuel A. Cohen ORCID: 0000-0002-8500-5526 Institution: Princeton Plasma Physics Laboratory Email: scohen@pppl.gov B. Associate or Co-investigator Contact Information Name: Charles Swanson ORCID: 0000-0003-0231-8525 Institution: Princeton Plasma Physics Laboratory Email: cswanson@pppl.gov C. Associate or Co-investigator Contact Information Name: Peter Jandovitz ORCID: 0000-0001-9803-6068 Institution: Princeton Plasma Physics Laboratory D. Associate or Co-investigator Contact Information Name: Sangeeta Vinoth ORCID: 0000-0001-5967-7436 Institution: Princeton Plasma Physics Laboratory Email: spunjabi@pppl.gov E. Associate or Co-investigator Contact Information Name: Liam David ORCID: 0000-0001-9803-6068 Institution: Princeton Plasma Physics Laboratory Email: ldavid@pppl.gov Alternate Contact Information: Name: Bruce Berlinger Institution: Princeton Plasma Physics Laboratory Email: bberling@pppl.gov Description: The data includes Excel, HDF5, TXT, TRC and MCA files for the experiments conducted using PFRC between 2014 and 2023. Data includes raw, intermediate and post processed data from the interferometer, fast camera, visible spectroscopy, SDD X-ray diagnostics, RF power characteristics, pressure gauges, probes, gas puff characteristics, axial boundary potentials, and residual gas analyzer (RGA). There is a lot of data in these files that are PDF documents made by scanning screenshots of Lecroy Digital Storage Oscilloscopes displays used to accumulate and analyze the data, Runsheet based on the diagnostics that displays the experimental parameters and the file numbers. Date of data collection: 20140424-20230801 Geographic location of data collection: Princeton, NJ, Mercer County, USA Funding sources or sponsorship that supported the collection of the data: DOE Contract Numbers: DE-AC02-09CH11466, DE-AC02-76CH03073 -------------------------- SHARING/ACCESS INFORMATION -------------------------- Licenses/restrictions placed on the data, or limitations of reuse: Creative Commons Attribution 4.0 International Recommended citation for the data: Cohen, Samuel A., Swanson, Charles, Jandovitz, Peter, Vinoth, Sangeeta, David, Liam, & Berlinger, Bruce. (2024). Data from the Princeton Field Reversal Configuration (PFRC) Experiment [Dataset]. Princeton Plasma Physics Laboratory, Princeton University. 10.34770/8ecv-zm19 Citation for and links to publications that cite or use the data: https://w3.pppl.gov/ppst/pages/pfrc_papers.html -------------------- DATA & FILE OVERVIEW -------------------- File list: The files are contained in folders, each identified by date in the format YYYYMMDD. The files in each folder have titles that represent the type of data stored in them. Most data is in the form of screenshots from Digital Storage Oscilloscopes (DSOs). (See description of these screenshots at the end of this README.) -------------------------- METHODOLOGICAL INFORMATION -------------------------- Description of methods used for collection/generation of data: The data was collected by DSOs connected to the various diagnostics on the PFRC device. Software- or Instrument-specific information needed to interpret the data, including software and hardware version numbers: The DSO are all manufactured by LeCroy. Environmental/experimental conditions are described in files named date-Runsheet.pdf The primary people involved with sample collection, processing, analysis and/or submission have been: S.A. Cohen, C.P.S. Swanson, P. Jandovitz, S. Vinoth, L. David, B. Berlinger -------------------------- DATA-SPECIFIC INFORMATION -------------------------- The main data in these files are PDF documents made by scanning screenshots of Lecroy DSO displays used to accumulate and analyze the data. These are in files named “date”-scope-#. Examples are shown below. The appearance of each screenshot indicates what data it displays. Additionally, there are PDF documents identified as “Date-Runsheet.pdf” that provide machine parameters, such as fill gas species, fill gas pressure, current in the magnetic field coils, RF power, both for the capacitively coupled system (Pcap = 87*V1.79 W) and for the RMF system (for each antenna set, 2PRMF = 430*V2 kW), duration of the discharge, frequency of the RMF system, RMF pulse repetition rate, and time when data was taken. A blank runsheet is at the end of this README. Timeline Description automatically generated with low confidence PDF of Lecroy DSO showing forward and reverse RMF powers for the two antenna sets. Top: N/S antenna set. Bottom T/B antenna set. Bottom table – values averaged over 127 discharges. Example for N/S forward power. N/SPRMF = 430*V^2 kW/2 = .4372 430 = 41 kW. The reflected N/S power is a small fraction of the forward power, (29.6/437.1)2 = 0.46% A screen shot of a computer Description automatically generated PDF of Lecroy DSO showing absorbed RMF power from the two antenna sets. Top traces - Yellow (c1): N/S antenna set. Green (c4): T/B antenna set. Bottom trace (Ma) –T/B power, averaged over 731 pulses. 1 kW/mV. Example for T/B absorbed power. Pa,T/B = 16 mV x 1 kW/mV = 16 kW A graph with a blue line Description automatically generated PDF of Lecroy DSO showing interferometer data. Blue upper trace (F3) = single shot; n ~ 1.34 x 1012/cc/V. Lower traces: raw interferometer data. Example. Line-averaged ne seen ~ 5 Volts ~ 6.5 x 1012/cc, assuming 8-cm-radius plasma. Other measurements show the radius to be smaller, ca., 5 cm, which yields a higher density, 1.04 x 1013/cc. FFTs of density data are sometimes made. A screen shot of a graph Description automatically generated PDF of Lecroy DSO showing Gas puff data: Top traces. Blue - trigger signal to pulsed gas valve. (Trigger at negative slope.) Black – measured voltage at the gas valve. Bottom trace – voltage pulse provided to gas valve/10. Example: 46 volts seen in lower trace. Concerning the odd shaped black upper signal – the exponential decay is due to the capacitance of the coax cable connecting the pulse gas valve to the pulser. A graph with a line graph Description automatically generated with medium confidence PDF of Lecroy DSO showing Cup voltage, Vcup, vs time. Capacitive discharges lower the paddle potential, here to ~ - 700 eV. Application of RMF causes the cup potential to rise towards or exceeding 0 volts. HV probe /1000. The Green trace is pickup of the RMF; the Brown is a single shot measurement of Vcup; the dark Blue is the average of ~ 100 shots. A graph with a blue line Description automatically generated PDF of Lecroy DSO showing Tantalum paddle voltage, VTa, vs time. Capacitive discharges lower the paddle potential slightly, here to ~ - 8 eV. Application of RMF causes spikes in the paddle potential, sometimes + and , sometimes -. A graph with a blue line Description automatically generated PDF of Lecroy DSO showing Voltage on paddle in FEC/1000, averaged over 12 discharges. RMF begins at caret (2 divisions) and ends at 8 divisions. The + going signal at 2.4 divisions is ~ 1.8 div x 0.5 V/div x 100 = 0.9 kV. A screen shot of a graph Description automatically generated PDF of Lecroy DSO showing RGA spectrum in FEC. Partial pressure vs AMU. The hydrogen pressure in the CC is about 100x higher. PDF of Lecroy DSO showing SDD measured X-ray spectra, 5 peaking times. A screen shot of a graph Description automatically generated PDF of Lecroy DSO showing X-ray arrivals vs time. Each red spike corresponds to a detected X-ray. There are additional data taken with the Fast Camera. These data are in HDF5 format. Some Interferometer data are also in HDF5 format. The Excel sheets are the post processing of the SDD X-ray spectrum or Spectroscopy. The .txt files are visible spectroscopic data and parameter files. The data files go back to April 2014. During this period four different RMF frequencies were used on the PFRC. (The RMF frequency at which we operated is noted on each Runsheet. The table below serves as a shorthand.) Daily tuning of the RMF system might change the operating frequency by ~ 0.2%. +----------------------------+---------------------------+------------------------+ | Apprx RMF frequency (MHz) | Start date (MM-DD-YYYY) | End date (MM-DD-YYYY) | +----------------------------+---------------------------+------------------------+ | 8.0 | 01-01-2011 | 05-13-2019 | | 6.0 | 05-20-2019 | 11-11-2019 | | 4.3 | 12-05-2019 | 11-01-2022 | | 1.8 | 11-05-2022 | --- | +----------------------------+---------------------------+------------------------+ Sample Runsheet Application, table, Excel