trackreco / mkFit

Vectorized, Parallelized Tracking
https://trackreco.github.io/
Apache License 2.0
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fix curv->CCS (3,0) #330

Closed slava77 closed 3 years ago

slava77 commented 3 years ago

while cross-checking the results of #324 I found a typo; this PR fixes the curvilinear to CCS Jacobian element that couples q/p with 1/pt. The impact of the mistake was a decrease in uncertainty of 1/pt by sinTheta^2 (cosLambda^2) in the input seed

http://uaf-10.t2.ucsd.edu/~slava77/figs/mic/mtv/10muHS_mk48b9f5b_sw5766e9f_vs_25bd4b9_v_mka3eddef-sw25bd4b9/

for built track initialStep: imageimageimage

orange is new/fixed

slava77 commented 3 years ago

additionally, from standalone val in TTbar PU50 (left: older Cartesian -> CCS, middle: Curv-> CCS before this PR, right: fixed-up Curvilinear-> CCS with this PR)

imageimageimage

nHits is back to the same distribution as expected; other distributions are mostly unchanged because once a few hits are added (as in the majority of the tracks) the fit mostly recovers the correct parameters.