Bug #1751

Detector Alignment

Added by Hunt, Christopher over 8 years ago. Updated over 8 years ago.

Start date:
21 September 2015
Due date:
% Done:


Estimated time:


The tracker alignment issue (#1696) suffered some difficulties and eventually started to use the TOFs to determine the overall alignment of the detectors. This helped to some degree but highlighted other issues.

At present I am able to correlate tracks between the following detectors successfully:
-- TOF1 --> Upstream Tracker
-- Upstream Tracker --> Downstream Tracker

Propagating between:
-- Downstream Tracker --> TOF2
-- Downstream Tracker --> EMR
produces a sign flip in the X direction. I am not sure why yet.

Durga: TOF geometry and recon is correct.
Francois: EMR agrees with TOF.

Started relying entirely on the CDB geometry for the reconstruction now (and found a couple of bugs that are being fixed). But still looking for the cause of this misbehavior.

Related issues

Related to Analysis - Bug #1752: Geometry issuesClosedBayes, Ryan21 September 2015


Updated by Hunt, Christopher over 8 years ago

Found some bugs in latest geometries (69 & 70). Awaiting a fix. (No detector rotations)
Also found bug in Geometry for Run #07157. Can amend by hand while the bug is being addressed. (Incorrect Station Position)


Updated by Hunt, Christopher over 8 years ago

Update from Durga:

TOF2 may be have an error in the cabling. A HV scan reveled that the number was reverse of what was expected.

Hopefully this will fix the Downstream Tracker -> TOF2 Disagreement.

Will post results once this is addressed.

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