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ii_skyimage deconvolves shadowgrams in the given energy bands
for each Science Window, using the balanced
cross-correlation method described above. The energy bands should be either
the same as in the ibis_binning or the bands created by the
merger of those bands.
The deconvolution is weighted by efficiency. Thus the weighting array
contains
efficiency for normal pixels and 0 elsewhere.
A search for sources
is performed in the deconvolved image. The list of sources found
is created and the images are cleaned from the PSF ghosts.
In the deconvolved image, the pixel value at the source position is the total
source flux in cts/sec units. It is calculated as if the source was in the fully coded
field of view (FCFOV). One should NOT do any integration in the source region to estimate the flux from the image.
The source flux estimation given in the source list is slightly different as
the source flux is given at the fitted source position.
For each output energy band all images of the same type
are combined into one mosaic image.
A search for the sources in the mosaic image is
then performed and a list of sources found is created.
The current version of software allows you to create the mosaic separately
from the main analysis (see Section 7.1 for the details).
The Parameter PixSpread sets whether the source
flux is spread, or not in the mosaic image.
No-spread mosaic puts the whole input pixel count into
one output map pixel. It permits better flux and signal-to-noise ratio approximation as
each pixel count and variance is summed without any error. On the other hand
it can give some undesired effects as double source peaks because of binning.
In the spread mosaic the input pixel count is spread between some number
of output map pixels. This method is better for source position recovery
but not so good for source flux estimation, because of the source peak height reduction.
Furthermore, neighbouring pixels in the individual Science Window images are correlated
and correct spread variance calculations should take this into account.
But as exact calculation of the covariance matrix is too heavy for on-line
analysis, the approximative variance formula is used.
The ii_skyimage parameters are given in the Table 19.
Table 19:
ii_skyimage parameters included into the main script.
|
|
|
|
Name |
Name |
Type |
Description |
(in the main script) |
(executable) |
|
|
OBS1_mask |
mask |
string |
DOL of the MASK pattern fits file
default: `` '' |
OBS1_deco |
deco |
string |
DOL of the projected decoding pattern fits file
default: `` '' |
OBS1_DataMode |
DataMode |
integer |
Data Simulation mode
possible values:
0 - shadowgrams are treated
1 - shadowgrams are simulated
default: 0 |
OBS1_SearchMode |
SearchMode |
integer |
Source search mode
possible values:
0 - search for all significant excesses
1 - search for all catalog sources
2 - search for K sources,where K= ToSearch
3 - search for all catalog sources plus K significant
excesses,where K = ToSearch
Parameter SearchMode=
concerns only images at a Science Window level.
In the mosaic image ii_skyimage always
looks for K = ToSearch sources.
default: 3 |
OBS1_ToSearch |
ToSearch |
integer |
Number of sources to be looked for.
default: 50 |
OBS1_CleanMode |
CleanMode |
integer |
Ghost cleaning
possible values:
1 - source model lobes are subtracted from the deconvolved image
-1 - no subtraction
default: 1 |
tungAtt |
tungAtt |
string |
DOL of the Tungsten attenuation length fits file
default: `` '' |
aluAtt |
aluAtt |
string |
DOL of the Aluminium attenuation length fits file
default: `` '' |
leadAtt |
leadAtt |
string |
DOL of the Lead attenuation length fits file
default: `` '' |
OBS1_ScwType |
ScwType |
string |
Type of Science Window to be treated
possible values: ``POINTING'', ``SLEW'', ``OTHER'', ``ANY''
default: ``POINTING'' |
OBS1_DoPart2 |
DoPart2 |
integer |
if 1 or absent
do mosaic part.
Set it to 0 if you don't want to produce a mosaic image.
default: 1 |
OBS1_MapAlpha |
MapAlpha |
real |
Mosaic map center [deg]
default: "" |
OBS1_MapDelta |
MapDelta |
real |
Mosaic map center [deg]
default: "" |
OBS1_MapSize |
MapSize |
real |
Mosaic map radius [deg]
default: 40.0 |
OBS1_PixSpread |
PixSpread |
integer |
0 - no flux spread in mosaic
default: 1 |
OBS1_MinCatSouSnr |
MinCatSouSnr |
real |
Software detects the catalog source only if its signal-to-noise ratio
is higher then this value. This parameter has no meaning for the Science Window level images if
OBS1_SearchMode=1,3.
default: 6 |
OBS1_MinNewSouSnr |
MinNewSouSnr |
real |
Software detects a new source only if its signal-to-noise ratio
is higher then this value.
default: 7 |
OBS1_SouFit |
SouFit |
integer |
0 for fitting source position and 1 for fixed source position in ScW fit
default: 0 |
OBS1_ExtenType |
ExtenType |
integer |
exposure/residual maps
possible values: 0 or absent - Residual Map at 4*n-th extension of ima idx
1 - Exposure Map only at 4*n-th extension of ima idx
2 - both Residual and Exposure maps at 4,5*n-th extension of ima idx
3 - one Expo map at the end of ima idx
if ExtenType=1,2,3 the Mosaic Exposure Map is at the 4*n-th extension of mosa idx (instead of the on-time map)
default: 2 |
OBS1_NegModels |
NegModels |
integer |
0 or absent for no negative models ; 1 - negative models
default: 0 |
OBS1_FastOpen |
FastOpen |
integer |
if 1 then no CommonPreparePars
default: 1 |
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