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                                    NUSTAR
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NuSTARDAS v1.4.0:

- Major changes introduced in this version:

  * nuexpomap: 1) addition of a new parameter named 'indet2instrfile' to allow the generation of sky exposure map starting from a DET2 instrument map; 2) algorithm optimization for execution time reduction;

  * nubackscale: addition of a new parameter named 'inexpomapfile' to provide in input a sky exposure map. This change allows to skip the internal generation of exposure maps and reduces the task execution time;

  * nulccorr: addition of two new parameters named 'inskyinstrfile' and 'inaspecthistofile' to provide in input a sky instrument map and the associated aspect histogram file. This change allows to skip the internal generation of sky instrument maps and reduces the task execution time;

  * numkarf: addition of a new parameter named 'inexpomapfile' to provide in input a sky exposure map in the case of extended sources (parameter 'extended=yes'). This change allows to skip the internal generation of exposure maps and reduces the task execution time;

  * nuproducts: 1) addition of the new input parameter 'rungrppha' to group the source energy spectrum through an internal run of the FTOOL 'grppha'; 2) addition of an internal run of the 'nuexpomap' module and modification of the calls to the 'nubackscale', 'nulccorr' and 'numkarf' modules;

  * nucalcpi: modification of the algorithm for GRADE 0 and GRADE 9-20 events;

  * nupipeline: 1) handling of compressed TLE files in input; 2) syntax  modification to support latest Perl versions.

Summary of changes:

- nuexpomap/nubackscale/nulccorr/numkarf/nuproducts:

 Performance improvement to avoid multiple runs of nuexpomap. The software now allows the user to store a single DET2 instrument map file (through the det2instrfile output keyword call to nuexpomap) and reuse this file for future runs, including changes to the vignetting energy, etc.  See section 4.9 of the NuSTARDAS User's Guide for more details and syntax.

 This has resulted in a dramatic speed increase for nuproducts runs, with decreases in run times of 20 to 80%, depending on the exact parameters.

- nucalcpi:

 Slight change in the reconstruction algorithm for how events with Grade 0 and Grades 9 through 20 are handled in the software. This change allows for fine tuning of the GRADE_GAIN and GRADE_OFFSET columns in the CLC CALDB file. There are associated updates to the CLC CALDB files (see CALDB release notes) which marginally improve the gain correction for all events.