I made a few modifications to the facility for retrieving fit information from the report.out file from COCOA (using Samir's modifications to the code). These consist of a mother script createSamir_cms_slm.com, a daughter script px.com, and an awk script getframeALL.awk to do the heavy lifting. The awk script handles the transformation of errors to the new coordinate system (assuming the original ones were independent).
I also modified the script given MEp1_SLM2_Z_real_link_laser.C to make it easier to modify in the future (parameterized the data positions so it only requires you to edit one place in the file). It is not backwards compatible with the old version, since I supply more data in the slm.dat and cms.dat files created by my utilities.
The result is
Notice the tilt and the motion towards the IP when the magnet turns on.
This fit uses the ME+1/SLM2 model together with the first iteration fit values for the link disk position and angles. In other words I use only select parts of the link system to make my connection.
Above shows the difference between using the original Link fit (field off) with Endcap field on data and then using refit Link fit (field on) with Endcap field on. First there is the standard fit, using a loose Z position for the transfer plate measurement. Then it is tightened, and then moved. The inner chamber doesn't budge: its position is determined by the Link measurements.
The above shows the effect of varying the transfer plate Z-sensor value by 10 mm.
22-July: Updated the above with correct DCOPS hits.
22-July: Updated the above with correct starting pixel locations.
A package of utilities for processing report.out is here.
Modified 22-July-2008 at 20:31
http://hep.physics.wisc.edu/~jnb/cms/21Jul2008
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