This creates headers in the current FITS header that record the number and names of all the immediate parents in the supplied NDG provenance structure. It also records the number of root parents—those without ancestors—and their observation identifiers from component OBIDSS within the MORE component of the supplied provenance structure. These are the observations.

The names follow CADC convention as follows. For the immediate parents:

PRVCNT = _INTEGER / Number of parents PRV1 = _CHAR / Name of the first parent PRV2 = _CHAR / Name of the second parent : : : : : : PRVn = _CHAR / Name of the PRVCNTth parent

for the root provenance: OBSCNT = _INTEGER / Number of root-ancestor headers OBS1 = _CHAR / First observation identifier : : : : : : OBSn = _CHAR / OBSCNTth observation identifier

and the output file name: FILEID = _CHAR / Filename

The above headers are prefaced by a blank header and a title " Provenance:" comment.

The PRODUCT keyword’ s value is modified for FITS extensions. It has ’ _$<$extname$>$’ appended where $<$extname$>$ is the lowercase name of the standard EXTNAME keyword.

CALL CVG_PCADC( IPROV, FUNIT, STATUS )

IPROV = INTEGER (Given)

FUNIT = INTEGER (Given)

STATUS = INTEGER (Given and Returned)

• Ancestors that have been flagged as " hidden" are ignored.

• A warning is issued if the OBSIDSS component cannot be found for a root ancestor. The value of OBSCNT gives the number of ancestors with an OBSIDSS value.

The FITS file must already be open. The current HDU in the FITS file should be the primary and the standard headers should be present.