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User manual for SPI data simulation
For more information please read the individual help files of the programs used (e.g. spi_osim --help). Click here for a shematic overview of the simulation.
step purpose What you have to do
setup   have your own data_rep on your account. Follow the setup advice. I suggest that you do your simulation in a directory like .../data_rep/obs/my_simulation/ to have the same directory structure as for real data.
setenv COMMONLOGFILE mylog.txt define a logfile If you want to have a log file, set it now. To unset it later just type "unsetenv COMMONLOGFILE"
mkdir spi create output directory all your output files will be located in the spi/ subdirectory
spi_osim simulation and analysis This script does the sky simulation and the analysis by spiros and spiskymax. Please check carefully the parameters you use. You can start using this parameter file. spi_osim calls gensky, os_pdefgen, spisimprep, spi_allgti, spidead, spiback, and (optional) performs the analysis using spiros and/or spiskymax. No stepping back in the analysis is possible. Start from scratch again, in case the processing fails.
  use these tools to display the detector spectra and the spiros output spectra. Note: the input of an observation group will not work (as the observation group created by the simulation is not fully standard), thus give the DOLs of the individual files you want to display.
XSPEC spectral fitting You can use SPIROS output spectra inside XSPEC. You find a detailed description here. Note that there has no off-diagonal response applied in the simulation, so you should also apply a diagonal response inside XSPEC. After following the instructions how to prepare the spectra for XSPEC use the diagrsp command inside XSPEC.

In case you prefer to run all single steps manually, please follow this procedure:
step purpose What you have to do
gensky simulate sky images create SPI.-SKY.-IMA-IDX and attached images for a defined number of sources and sky. Use as an example this gensky.par parameter file.
os_pdefgen pointing definition Use as an example this os_pdefgen.par parameter file.
mkdir spi   Create output directory
spisimprep   create additional files needed. Use as an example this spisimprep.par parameter file. You need spisimprep 3.0 to perform this step.
spidead dead time create a dead time file. In the parameter file you have to set the deadtimecorrection value (i.e. the fraction of time the detector was alive) to a fixed value (e.g. 1.0). Otherwise spidead will exit with an error.
spiback background create a background file. Don't use the SCHK input functionality, i.e. use only fixed background models (constant, sine, cosine...).
spiskycnv skymap convolution Use as an example this spiskycnv.par parameter file. Make sure that you use parameter: OG_or_ATTI,s,h,"PNT",,,""
spiros source reconstruction The latest version of spiros should run without problem on the output of the simulation. For the different ways of using spiros, look into the spiros user manual
spiskymax image reconstruction The latest version of spiskymax should run without problem on the output of the simulation. For the questions about the usage, look into the spiskymax user manual
cat_extract is not running on these simulated data, as it needs a science window group index.

In case of questions and comments: contact me.