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: http://xmm.vilspa.esa.es/sas/7.0.0/doc/dpssflag/node3.html
Дата изменения: Thu Jun 29 00:04:28 2006 Дата индексирования: Sat Dec 22 09:29:32 2007 Кодировка: Поисковые слова: п п п п п п п п п п п п п п п п п п п п п п п п п п |
The aim of this task is to flag sources in EPIC combined source list in an automatic way for later purification through visual screening.
The flags for each source are written back to the input source list using the column named ``FLAG''. The final flag string is a list of T/F characters, T in the position where the corresponding flag is set and F otherwise. The initial flag string is thus ``FFFFFFFFFF''.
Those sources with SCTS=NULL are not flagged.
The list of flags set by the task is as follows:
The circle radius (in arcs) is calculated using task input parameters brcolumn,op1, op2 and brfactor as follows:
op1 | op2 | Expression |
sqrt | add | sqrt(brcolumn(i)) + brfactor |
sqrt | mul | sqrt(brcolumn(i)) * brfactor |
sqrt | none | sqrt(brcolumn(i)) |
none | add | brcolumn(i) + brfactor |
none | mul | brcolumn(i) * brfactor |
none | none | brcolumn(i) |
This 'circle of influence' will have a minimun and a maximum value given by the input parameters minrad and maxrad.
radius(i) = EXT(i) * extfactor
Note: This radius is internally converted to arcs taking into account the pixel size of the images used for the source detection.
This 'circle of extended emission' will have a maximum value in arcs given by the input parameter maxextrad.
The starting value for a source being considered an extended source is controlled by parameter extlimit. Therefore those sources whith EXT value lower than extlimit will not be considered as 'extended' and will not define an area of extended emission.
SCTS(causing_src) > brlimit
Distance is calculated using information in the first ID_BAND=0 row and then propagated to the other ocurrences of that source.
brcolumn(src_flagged) < brexfraction * brcolumn(causing_src)
Distance is calculated using information in the first ID_BAND=0 row and then propagated to the other ocurrences of that source.
DET_ML(i,one_of_15_images) > detmlfraction * det_ml_sum(1:15)(i)
distance(i) = badcolum(i) * badfactor
Flag 9 for PN camera is switched off by default (see parameter pnclosetobadon).
The activation of Flags 8 and 9 in PN band 1 or MOS1 CCD 1 bands 1,2,3 sources also sets these flags to 'T' for summary rows (ID_INST=0 and ID_BAND=0).