New Horizons Alice Calibration Reference Files - Overview
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Content
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This collection contains ancillary files used in the calibration of data
from the Alice Ultraviolet Imaging Spectrograph instrument for all phases of
the New Horizons primary and extended missions. These files are not the result
of Alice observations. They consist of a set of ancillary files (dark, effective
area, wavelength, flat).

Some products appear in multiple versions as a result of improvements
in calibration algorithms and pipeline processing over the course of
the missions. For these product lines, the calibrated data will reference
the specific version of the product in this collection that was used in
its production. So while some of these files were "superseded" in terms
of what was used in later versions of the pipeline, they are not
"superseded" in an archival sense because they are applicable to the
data produced using them.

The files were presumably collected by the Alice team, but no attribution was
provided in the PDS3 data. The PDS4 migration was performed by SBN personnel,
who are credited as editor of this collection.

Calibration files updated after the KEM1 mission phase were (will be) updated
by the New Horizons SOC team and are produced in the PDS4 standard. When updated
files are added to the collection, New Horizons SOC team members will be added to
either the author or editor lists.


PDS3 to PDS4 Migration Notes
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The PDS3 versions of these calibration files were duplicated cumulatively
in every Alice PDS3 dataset archived. For the migrated PDS4 archive, only
a single instance of each version of each file was retained.

The PDS3 labels, which contained minimal metadata beyond data structure, were not
retained in the migrated PDS4 archive but are  accessible in archival copies of the
PDS3 datasets retained in the NSSDCA deep archive.


Version History
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PDS4 v1.0: 2024-05-23, A. Gicquel
Initial version of the ALICE calibration files, ported from the PDS3 K5 dataset
(and earlier) as described in the Content section.

PDS4 v2.0: 2024-08-14, M.K. Crombie, B.L. Enke
Added the pa_row_offset_001.fit file.
