Software Release HEASoft 6.30 / NICERDAS 9


This page discusses new changes available in NICERDAS version 9, distributed in HEASoft 6.30. This release is not a major NICER software or calibration release, however there are some NICER-related internal changes.

Read this thread if you want to: Understand NICERDAS 9 software

Last update: 2022-04-25


Obtaining useful scientific results from NICER observations is a combination of NICER observational data with software and calibration products. Over time, NICER is committed to improving software and calibration so that scientists can get the most out of their data.

This page discusses changes available in NICERDAS 9, released with HEASoft 6.30 in mid-April, 2022.

HEASoft 6.30 is not a major NICER software feature release. There are no major new NICER-releated capabilities, and the NICER team does not recommend to go back and reprocess older data (processed with HEASoft 6.29) with HEASoft 6.30. There are also no new NICER calibration products since xti20210707, which was released in July 2021.

As always, we recommend users to document which version of software they are using, especially for publication. This will help future analysts repeat your results. For more information, see the Reporting NICER software and calibration versions thread.

NICER Software Changes

Here is a brief summary of the software changes delivered with HEASoft 6.30.

nicerl2 has a bug fix to properly handle the detlist parameter (previously events from "deselected" events could make it into the event file even though they were marked as deselected).

nicerl2 also has some logic to handle large gzipped event files - it will unzip them temporarily - which should solve large memory and performance issues. nicerl2 also writes the SOFTVER keyword so that processing versions can be tracked.

niprefilter2 has been rewritten completely to improve performance. You should see not-quite 2x overall performance improvements. For example runs of nicerl2 in our testing that took 100 minutes should now take 60 minutes. niprefilter2 also has a bug fix which correctly writes rarely-used filter file columns for long observations.

nicerarf will print some more informative messages for common error conditions that we were getting a lot of questions above.

Related Topics

For instructions on setting up a NICER analysis environment, please see the Setting Up a NICER Analysis Environment thread.

For more information on recommended settings and calibration recommendations, please see the NICER Calibration Recommendations analysis thread.

For release notes for the previous release (HEASoft 6.29 / NICERDAS 8) as well as calibration release xti20210707, please see the Software Release HEASoft 6.29 / NICERDAS 8 and Calibration xti20210707 thread.


  • 2022-04-25 - initial draft