add change deltaZLum to new recommendation

[YonsiG]

Change the deltaZLum in constant.h to a more recent LHC optics. This was meant originally to cover a luminous region along the beamline [-15, 15 ] cm (in z) used in segment building pointing constraints. The beamspot was roughly expected to be 5 cm Gaussian. This is a 3 sigma. More recent LHC optics suggests that the width will be smaller (4.3 cm), so the deltaZLum is changed to 12.9cm.

Comparisons from efficiency and fake rate suggests that efficiency doesn't have visible changes, but fake rate drops. The most visible fake rate drop is pT3

[YonsiG]

Comparison of performance with master: http://uaf-10.t2.ucsd.edu/~yagu/SDL_GPU_plots/test_PR/test_changeZLum/comparison/ master Only: http://uaf-10.t2.ucsd.edu/~yagu/SDL_GPU_plots/test_PR/test_changeZLum/master_17e088-PU200/ This PR Only: http://uaf-10.t2.ucsd.edu/~yagu/SDL_GPU_plots/test_PR/test_changeZLum/changeZLum_17e088D-PU200/

[YonsiG]

Also want to compare with the muonGun samples Comparison of performance with master: http://uaf-10.t2.ucsd.edu/~yagu/SDL_GPU_plots/test_PR/test_changeZLum/muonGun_compareZLum_17e088-muonGun_902251-muonGun/

[YonsiG]

Comparison for cube 5cm sample with master, if take a look closely, the efficiency drop a bit. http://uaf-10.t2.ucsd.edu/~yagu/SDL_GPU_plots/test_PR/test_changeZLum/cube_comparison_changeZLum_17e088-cube5_902251-cube5/compare/

[VourMa]

@YonsiG Is this supposed to go in after all or should we close it?

[YonsiG]

Hi Manos, I think we can close it. This PR is linked to the object cuts gdoc and the decision is to not change the deltaZLum allowance. https://docs.google.com/document/d/1MZqSnR-q8YmWN0X4CZIjjV2mYRVW8UxCZnn1NR34ppw/edit?usp=sharing