...
There is no correlation between the angular differences and the LIVETIME differences.
Merit files
I've compared:
- original=root://glast-rdr.slac.stanford.edu//glast/Data/Flight/Level1/LPA/prod/5.7/merit/r0634002957_v001_merit.root
- new=root://glast-test-rdr.slac.stanford.edu//glast/Data/Flight/Level1/LPA/dev/5.9/merit/r0634002957_v000_merit.root
And I see the same differences for the variable FT1Ra and FT1Dec.
Pieces of code
The variables FT1RA and FT1Dec are filled in AnalysisNtuple/src/FT1Alg.cxx:
- gps = astro::GPS::instance();
double etime(header→time());
gps→time(etime);
- glastDir= Hep3Vector(CTBBestXDir, CTBBestYDir, CTBBestZDir);
- this information is the same in both merit files
- SkyDir sdir( gps->toSky(glastDir) );
- m_ft1ra = sdir.ra();
- m_ft1dec = sdir.dec();
The gps object lives in astro/src/GPS.cxx:
- astro::SkyDir GPS::toSky(const CLHEP::Hep3Vector& latdir, double met)
- CLHEP::Hep3Vector tdir( - (m_currentPoint.rotation() * m_alignment * latdir) );
- void GPS::update(double inputTime)
- //this function calculates all the relevant position and orientation info
- the differences could come from his part of the code