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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 [*] 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 [*].

Table: 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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