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Old matrices

The following are the matrices that we used during the online analysis of the experiment:

[1] LHRS default matrix - I cannot find this file. Might be able to retrieve it from github, but it would only be here for legacy reasons.

[2] RHRS default matrix

Optimization steps


The following is the LHRS matrix optimized by GMp

[3] LHRS GMp optimization

The following is an optimization that Shujie did on the GMp LHRS matrix [3] using the standard procedure for optimizing the angles and the sieve runs taken during MARATHON.

[4] LHRS re-optimization by Shujie

Details on Shujie's optimization here


The following is the RHRS matrix optimized by GMp

[5] RHRS GMp optimization

Current (optimized) matrices


Replaced in matrix [4] the line:

D 1 0 0 -6.863500E-02 2.633700E-01 1.096600E-02 -7.253300E-02


D 1 0 0 4.932426E-03 2.633700E-01 1.096600E-02 -7.253300E-02

This is the coefficient that relates delta with theta x' fp linearly. We did this to get rid of a slope we saw in Emiss vs. xptar.

Screen Shot 2018-07-27 at 11.27.02 AM.png

[6] matrix with Emiss vs. xptar slope fixed

Last but not least, the term Y 0 0 0 2.670000E-03 was introduced to shift the LHRS ytar distribution. This was decided because, when plotting LHRS vz - RHRS vz for a coincidence cut, the coincidence peak was shifted from 0.

[7] current LHRS matrix


Replaced in matrix [5] the line:

D 0 0 0 1.816209E-03 8.382911E-02 7.297953E-03 3.822568E-03 1.149510E-02


D 0 0 0 6.146531E-04 8.382911E-02 7.297953E-03 3.822568E-03 1.149510E-02

and added the following two lines:

T 0 0 0 -2.940000E-03

P 0 0 0 -1.567257E-03

These are overall constant shifts introduced by looking at hydrogen data to shift distributions to where there physical values should be (i.e. W 937 -> 938.27 MeV)

[8] current RHRS matrix