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                                    NUSTAR
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NuSTARDAS v2.0.0:

Requirements: NuSTAR CALDB 20200YXX

This NuSTARDAS implements a new temperature-dependence during the ARF
generation that should improve performance in a small number of cases
for FPMA. The software change is required to account for cases where
the optic for FPMA is "cold", implying a decrease in the effectiveness
of the thermal blanketing (MLI) and a corresponding increase in the
low-energy transmission. This primarily affects observations after 2018.

This builds on the long-term ARF changes for FPMA documented here:

 https://heasarc.gsfc.nasa.gov/docs/heasarc/caldb/nustar/docs/release_20200429.txt

The accompany CALDB patch 20200YXX contains the temperature-dependent
corrections and is required for this software version.

Details on the issue can be found in this paper:

 https://arxiv.org/abs/2005.00569

More details about the MLI correction can also be found here:

 http://www.srl.caltech.edu/NuSTAR_Public/NuSTAROperationSite/mli.php


:: Note ::

This patch requires access to the optics bench housekeeping file
(obebhkfile). This file is distributed for each observation in the
"hk" subdirectory from the HEASARC. If an observation is downloaded
from the HEASARC, as always, we recommend running nupipeline to
recalibrated the data using the latest CALDB files. This will copy
the OBEB HK file into the output directory (commonly the "event_cl"
directory). No further action is required by the user as these input
files are automatically detected by nuproducts during later analysis
if they are present in the event_cl directory.

To call nuproducts directly on the data downloaded from HEASARC
requires the use of new input keyword: `inobebhkfile'. Details of
this are described in the software user's guide

 https://heasarc.gsfc.nasa.gov/docs/nustar/analysis/nustar_swguide.pdf

and in the quickstart guide:

 https://heasarc.gsfc.nasa.gov/docs/nustar/analysis/nustar_quickstart_guide.pdf

:: Software changes ::

The major changes introduced in this version are:

- numkarf: 1) Added temperature dependency for ARF files CALDB query;
  2) Added new 'obebhkfile' input parameter and computation of
  "OPT0_5TEMP" average value.

- nuproducts: 1) Modified call of numkarf task; 2) Added new
  'obebhkfile' input parameter.

- nupipeline: 1) Modified call of nuproducts task; 2) Added new
  `inobebhkfile' and `obebhkfile' input parameters.

- nu_highfits: Modified to support TFORM values '1PD(X)/1PI(X)'.