Data Set Overview
    =================
      The following describes the nature of instrument operation
      during the various periods for which IES data are available in
      this submission.  In all cases the data are calibrated differential
      electron and ion energy flux as function of energy, azimuth (direction
      in the instrument symmetry plane) and elevation (angle above or below
      the symmetry plane).

      The Rosetta Comet Escort 3 (ESC3) covers the period from 2015-July-01 to
      2015-October-21, with Rosetta at various trajectories and distances from
      the comet. IES measured electrons generally below 200 eV. There are
      brief moments in which the electron detection is at all energies.

      The solar wind was not always visible in the RPC-IES FOV but pickup
      ions of energies up to ~several keV were frequently seen. Occasional
      gaps in the data are the result of telemetry dropouts.  On 13 August
      at 02:30 UT Rosetta passed through perihelion, its closest distance
      from the Sun, 1.24 AU, and ~327 km from the comet.  On 23 September
      2015 Rosetta began an excursion sunward of CG, reaching a distance
      of ~1500 km from the comet, then returning and resuming its previous
      type of trajectories. At the end of this phase Rosetta was ~421 km
      from CG and 1.49 AU from the Sun.

    Processing
    ==========
      All Rosetta Plasma Consortium (RPC) data packets are transmitted
      together during downlinks with Rosetta. RPC data are retrieved
      from the Data Distribution System (DDS) at European Space
      Operations Centre (ESOC) to a central RPC data server at
      Imperial College London. Data for IES is copied from the RPC
      central data server by IESGS at Southwest Research Institute.

      The pipeline processing software is the IES Ground System
      (IESGS). IESGS extracts IES CCSDS packets from the RPC
      collective data files stored on the RPC central data server at
      Imperial College. These packets are used to build ion and
      electron data products. The data products are grouped by date
      and written out to PDS compliant archive data files. One data
      file is created for each day. IESGS also generates the labels
      for the archive data files. IES science products, archive and
      label files, and limited spectrograms are available to team
      scientists on the IESGS website.

      For information on how the derived data files are created
      from calibrated data files, please see DOCUMENT\MOMENTS_CALCULATION\
      MOMENTS_CALCULATION.PDF.

    Coordinate System
    =================
      In order to determine IES pointing, attitude data for the
      Rosetta spacecraft is obtained through SPICE kernels.

      Level 5 files use Comet-centered Solar EQuatorial (CSEQ) as the
      reference frame to specify the velocity direction components. This is
      a common frame used in many other data sets and is referenced as
      '67P/C-G_CSEQ' in SPICE.

      SUB_SPACECRAFT_LATITUDE, SUB_SPACECRAFT_LONGITUDE are given in
      the Cheops reference frame. These parameters are computed at
      time t=START_TIME. Distances are given in km, angles in
      degrees.

Confidence Level Overview
    =========================
      This dataset is used by the IES science team after processing.
      This is done to ensure that the archived data contains good,
      valid products.

    Review
    ======
      This archival data set was examined by the IES science team
      prior to submission to the NASA Planetary Data System (PDS) and ESA
      Plantetary Science Archive (PSA). It was reviewed by PDS, PSA, and the
      Rosetta data archive working group.

    Limitations
    ===========
      None.