NuSTAR CALDB Release Version: 20200826
 
Release Type: CALDB release
 
CLOCKFILE:
==========
 
Contents:

fpm/bcf/clock/nuCclock20100101v109.fits

Summary of changes:
 
Clock files v.109 and later contain an improvement of the clock offset model that builds on the fine clock correction introduced in v.095. For clock files prior to v.100, the absolute alignment to UTC time has been measured to be systematically off by ~5ms  Additionally, the model used to produce the clock file suffered from time intervals with no temperature measurements (such as reboots of the system).
 
Clock file v.109 includes an absolute systematic shift of 4.9 ms and improves the treatment of these ̉bad" intervals.
 
More details about the impact of the clock correction file are available at the NuSTAR SOC at this link:
 
http://www.srl.caltech.edu/NuSTAR_Public/NuSTAROperationSite/clockfile.php