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 So while some of these files were "superseded" in terms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"superseded" in an archival sense because they are applicable to the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.

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.


2024-05-23, A. Gicquel