DOI: 10.5281/zenodo.7278490
title: New high time resolution mutual impedance measurements

description: =====================================================================================================<br> Author : L. Bucciantini<br> Date : 03/11/2022<br> Laboratory : CNRS-LPC2E, Orléans (France)<br> ===================================================================================================== Dear reader, we thank you for your interest in our dataset. In this document, we describe what you will<br> find in it. In case you need help with using the dataset, or if you are interested in mutual impedance experiments,<br> do not hesitate to contact our team in Orléans (pierre.henri@cnrs-orleans.fr, pierre.henri@oca.eu) =====================================================================================================<br> Topic:<br> This dataset contains the outputs of numerical simulations and experimental tests performed<br> to test and validate two new mutual impedance instrumental modes: the chirp mode and the<br> multi-spectral mode. These modes have the objective of improving the time resolution of<br> mutual impedance measurements. These new instrumental modes are validated by comparing their measurements to the classic<br> instrumental mode of mutual impedance measuremetns, the so-called frequency sweep mode. <br> Numerical model:<br> The numerical outputs are obtained from a numerical model based on the solution of the 1D-1V Vlasov-Poisson<br> system of equations. The scheme used to solve the model is the one developed<br> by Mangeney et al. (2002), A Numerical Scheme for the Integration of the Vlasov-Maxwell System of Equations. Journal of Computational Physics, (doi: https://doi.org/10.1006/jcph.2002.7071).<br> The 1D-1V Vlasov-Poisson version of this model is described in Henri, et al. (2010), Vlasov-Poisson<br> simulations of electrostatic parametric instability for localized Langmuir wave packets in the solar wind,<br> Journal of Geophysical Research (Space Physics), 115, 6106 (2010) Experimental testing facility:<br> The experimental outputs are obtained using the testing facility of CNRS-LPC2E space laboratory. It is<br> composed of a vacuum chamber, a pumping system and a plasma source. The pumps make vacuum in the<br> chamber (p=1e-5mbar). The plasma source generates a plasma flow that we use to test mutual impedance<br> instruments in a medium which is representative of Earth's ionosphere (100-2000 km of altitude). -----------------------------------------------------------------------------------------------------<br> Instrumental modes of interest frequency sweep (FS) mode : typical mode. Implemented for DFP-COMPLIMENT onboard Comet Interceptor chirp (CH) mode : new fast mode. It is based on the emission of only one period per frequency. multi-spectral (MS) mode : new fast mode. It is based on the simultaneous emission of multiple frequencies. -----------------------------------------------------------------------------------------------------<br> What is inside the dataset: The dataset is composed of 3 numerical and 6 experimental mutual impedance measurements.<br> The numerical measurements are obtained for the same plasma box but for different instrumental modes.<br> The experimental measurements are obtained for two different plasmas, monitored using the three different<br> instrumental modes. -----------------------------------------------------------------------------------------------------<br> List of directories: <br> Numerical_CH, Numerical_MS: Each of these outputs corresponds to a mutual impedance measurement<br> Numerical_FS performed using a different instrumental mode.<br> For MS and FS, inside the directory each folder corresponds to the<br> emission of a different frequency. <br> Experimental : It contains a txt file with inside the mutual impedance spectra obtained<br> for two different plasmas <br> -----------------------------------------------------------------------------------------------------<br> List of folders inside the directories: In the case of the numerical measurements, folders begin with the name "000" and have increasing index. ------------------------------------------------------------------------------------------------------<br> List of files inside the folders for the numerical measurements: density_e.npz : electron density inside the box, in function of time (tempo) density_p.npz : ion density inside the box, in function of time (tempo) E.npz : electric field in the box, in function of time (tempo) qrho.npz : electric potential in the box, in function of time (tempo) qrho_imposed.npz : electric charge imposed at the emitting antennas, in function of time (tempo) tempo.npz : time-vector for density, electric field, electric potential and charge vectors TEST_Luca.dat : parameters describing the characteristics of the simulated plasma box <br> [<br> Note : the previous files can be opened as follows import numpy as np vector_file_name = np.load('file_name.npz') # Use these for the .npz files<br> characteristics_of_the_box = np.genfromtxt('TEST_Luca.dat',skip_header=1) ] ------------------------------------------------------------------------------------------------------<br> List of files inside the folders for the experimental measurements: data.txt : frequencies and amplitudes associated to the measurements. [<br> Note : the previous file can be directly included into a python script ] -------------------------------------------------------------------------------------------------------<br> Characteristics of the simulated plasma box (TEST_Luca.dat) nx : amount of spatial grid points xl : physical size of the spatial box, expressed in Debye length tt_w : time resolution for ion and electron density, electric field, electric potential and charge rap_m : ion-to-electron mass ratio R_p : ion-to-electron temperature ratio dt : time step used to evolve in time the numerical simulation emission : emission frequency power : amplitude of the electric charge imposed at the emitting antennas <br> (Note : all parameters not listed here but present inside the TEST_Luca.dat file correspond to additional<br> functionalities of the model. For the use of this dataset, they can be discarded.)