This San Marco D/L Electric Field Experiment (EFI) data set was provided
by the PI team on 12 magnetic tapes in ASCII format and constitutes the
final EFI archiving product (filename: yymmddhhmm.dc). The data from the
first tape are available online in this directory. The following parameters
have been archived: (A) DC electric field (8 points per second) along
the X and Y axes in spacecraft coordinates; (B) Variational (AC) electric
fields averaged at 0.5 second intervals for all channels of each of the
three spectrometers; (C) Some orbital parameters such as the altitude of
the satellite, the geographic longitude and latitude, the local solar
time and the dip latitude, and a day/night flag for the DC data; (D) Non-
reduced plasma ion densities measured by the Ion Velocity Instrument
(IVI). The DC portion of the EFI experiment is only valid for non-reduced
IVI data > 2.5 volts corresponding roughly to an electron density of 10^4
electrons per cubic centimeter. Note that the AC data is valid at all
plasma densities. More details can be found in the acformat_sfdu.txt and the
voldesc_sfdu.txt files. Both of these files are ASCII text files.

Further details about the San Marco spacecraft, experiment, and data sets
can be found at the San Marco home page, http://crpsm.psm.uniroma1.it/