New Horizons Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) Post-Launch Checkout Raw Data, Version 1.0

This data set contains Raw data taken by the
New Horizons Pluto Energetic Particle Spectrometer Science Investigation
(PEPSSI) instrument during the LAUNCH mission phase. These data
were migrated from the PDS3 dataset: NH-X-PEPSSI-2-LAUNCH-V1.1.

PEPSSI is a particle telescope and a time-of-flight (TOF) spectrometer that
measures ions and electrons over a broad range of energies and
angles. Particle composition and energy spectra are measured for H to
Fe from ~ 30 keV to ~1 MeV (but not all species are uniquely separated)
and for electrons from ~30 keV to 700 keV. PEPSSI comprises a
time-of-flight (TOF) section and a solid-state detector (SSD) array
that measures particle energy. The combination of measured energy and
TOF provides unique particle identification by mass and particle energy
depending on the range: for protons from ~30 keV to ~1 MeV; for heavy
(CNO) ions from ~80 keV to ~1 MeV. Lower-energy (>3 keV) ion fluxes are
measured by TOF only, but without the SSD signal, providing velocity
spectra at these energies as well. Due to storage and bandwidth
limitations, all event data cannot be stored or telemetered to the
ground. Instead, a round-robin algorithm is used to save Energy, TOF,
and timing data for select events. The common data products contain
these event and summary measurements, accumulated over fixed periods of
86,400 seconds, with each period in a single file comprising multiple
binary tables.

During the Post-Launch phase of the mission, the PEPSSI
measurements concentrated on initial commissioning of the
instrument. The first PEPSSI commissioning activity was running
the full CPT on PEPSSI to confirm all instrument functionality
after launch. Then commands were sent to open the door, ramp up
bias voltage and HV and confirm full functionality. The
remainder of commissioning activities included calibrating the
instrument thresholds, determining HV settings, loading
classification tables and initialization macros, and
investigating and confirming the instrument pointing. There
were a few days of data collection in which protons and helium
are clearly identified. This phase includes periods in which
the instrument is in normal science mode and diagnostic mode.
The data taken during this period are not intended for scientific study.

Labels were redesigned during migration using the .FIT header and PDS3 .LBL
files, but the data files are unchanged from their PDS3 version.