ISOCAM Interactive Analysis User's Manual Version 5.0 - ISO - ESA

23.2. HELP ON X CIA 303
• Transient / 90% Of Final Flux (modeled): A model based on ground-calibrations is
used to determine the number of stabilized frames given the first and last flux values of
pixels.
• Transient / 90% Of Final Flux (measured) [default]: Pixel values exceeding the
last value ± 10% of the difference between the first and last values are considered as not
stabilized.
• Transient / IPAC Model Fitting: ThemodeldevelopedatIPACisusedtofitthe
transient behavior of the detector.
• Transient / IAS Model Fitting: The model developed at IAS is used to fit the transient
behavior of the detector.
• Transient / SAP Model Fitting: The model developed at SAP is used to fit the
transient behavior of the detector.
• Transient / Remove Ghosts: An adaptive filtering is applied in order to determine if
an upward or a downward transient is detected. If an upward transient is detected then the
last detected flux is considered as the stabilized one. If a downward transient is detected
then the stabilized flux is assumed to be equal to that of the background. This method
allows to remove all ghosts in the reconstructed raster map, but it can lead to a loss of
information (if a source is superimposed on a downward transient for example).
• Flatfield / None: No flat-field correction is performed.
• Flatfield / User Input: A user flat-field can be given as input in order to correct the
flat-field effect. The user must then use the following command to start the session:
CIA> x_cia, inflat=my_flat
my flat is a 32×32 array.
• Flatfield / Cal-G [default]: Flatfield is extracted from the calibration database.
• Flatfield / Auto: Flatfield is obtained by computing the median of all frames corresponding
to the same configuration. It is normalized on the 10 × 10 central pixels.
• Flatfield / Manual: Flatfield is built interactively by selecting only a subset of all
frames of the data cube and normalized on the 10 × 10 central pixels. This method is well
adapted whenever only background is observed at the edge of large raster map. If a source
is detected in each frame, it is also possible to exclude interactively some rectangular zones
before computing the flat-field.
• Process / None: Set to ‘None’ all calibration fields (Dark, Deglitch, Transient and
Flatfield).
• Process / Default: Execute the default data processing. Warnings are displayed if some
corrections have already been made to the current data set. Note that these warnings
concern only the current x cia session. So before processing data, the user should have a
look at the data history in order to check that some data corrections have not been yet
processed (see above Data / Display History).