Number Density of Electron by Impedance Probe (NEI)

Data directory

These are the spectrum data of the equivalent capacitance of the probe in the plasma observed by the NEI, the instrument to measure the number density of electrons.

Each data point consists of 512 electric-field intensity at a given frequency with the frequency range from 100 kHz to 24.3 MHz. The data files are in the CDF format.

The details of the specification of the data and instrument and of the NEI experiments are described in Takahashi et al. (1985).

If you have any questions, please contact the Ohzora/NEI Data Manager, Dr. Atsushi Kumamoto (kumamoto (at)

Last Modified: 14 February 2019