Examples of Split Sources


 

Source split in two by CCD gap:

(Sources split in three where three CCDs meet are also possible)
[000815-PN] [000815-PN] [000815-PN]
 EPIC PN image (netscape)  EPIC PN image (ds9)  EPIC PN image with sources overlaid (ds9): the two fat circles indicate a split source: green is the main component and cyan the false detection, both have the source comment 'Split by CCD gap'. All boxes have the flag 'Within extended' set.
 

 

Source split in two by CCD gap (symmetrical):

[000815-M1] [000815-M1] [000815-M1]
 EPIC M1 image (netscape)  EPIC M1 image (ds9)  EPIC M1 image with sources overlaid (ds9): the two fat circles indicate a split source with about equal brightness for each part. One component is taken to be real (green) while the cyan component is flagged as false. Both have the source comment 'Split by CCD gap'. All boxes have the flag 'Within extended' set.

 

Bright central source split in two by CCD gap:

Often the bright central source is detected several times along the edges of a CCD; theses cases will be flagged as false with the comment 'Wing of bright src'.
[001269-PN] [001269-PN] [001269-PN]
 EPIC PN image (netscape)  EPIC PN image (ds9)  EPIC PN image with sources overlaid (ds9): the two fat boxes indicate a split source: green is the main component and cyan the false detection, both have the comment 'Split by CCD gap'. All boxes have the flag 'Within extended' set.
 

 

Source split in two by a bad column in PN:

[001046-PN] [001046-PN] [001046-PN]
 EPIC PN image (netscape)  EPIC PN image (ds9)  EPIC PN image with sources overlaid (ds9): the two fat circles indicate a source split by a bad column: green is the main component and cyan the false detection, both have the source comment 'Split by CCD gap'.
 

 

Central source split in three due to pileup (not detected -> give position)

[000828-M2] [000828-M2] [000828-M2]
 EPIC M2 image (netscape)  EPIC M2 image (ds9)  EPIC M2 image with sources overlaid (ds9): cyan sources are flagged as false with the fat circles flagged for 'Split by pileup', while the others are flagged for other reasons (mainly 'Wing of bright src'). None of the 'split' sources is considered to be real and the central source will be listed as undetected with the coordinates being entered into the DPSS-log report.
 

 

Bright source at edge of field split into two due to pileup:

[000895-PN] [000895-PN] [000895-PN]
 EPIC PN image (netscape)  EPIC PN image (ds9)  EPIC PN image with sources overlaid (ds9): the two fat circles indicate a source off-center which is split by pileup: one component is OK (green) while the cyan component is flagged as false. Both have the source comment 'Split by pileup'.


Screening Notes Example: Version 29.05.2003