sPHENIX tracking discussion

["Pereira Da Costa, Hugo Denis Antonio" <hugo.pereira-da-costa AT lanl.gov>]

All,

So unfortunately, using the latest code from Macros, I still see very very 
few tracks mathcing to TPOT in our zero-field data, as soon as I require a 
silicon match. I might still be doing something wrong.

Now: looking at recent commit and discussing with Bade, I realized that our 
macro repository is somewhat of a mess, and makes it difficult to understand 
what we are running or talk to each other.

As an example, I looked into micromegas matching windows. There are 4 
parameters to be set there, controlled by:

     mm_match->set_rphi_search_window_lyr1();
     mm_match->set_rphi_search_window_lyr2();
     mm_match->set_z_search_window_lyr1();
     mm_match->set_z_search_window_lyr2();

Now, a simple grep into vanilla macro gives:

grep set_rphi_search_window_lyr1 `find -iname "*.C"`
./common/Trkr_Reco.C: mm_match->set_rphi_search_window_lyr1(0.2);
./common/Trkr_Reco.C: mm_match->set_rphi_search_window_lyr1(0.2);
./common/Trkr_Reco.C: mm_match->set_rphi_search_window_lyr1(0.4);
./common/Trkr_TruthReco.C: mm_match->set_rphi_search_window_lyr1(0.2);
./common/Trkr_TruthReco.C: mm_match->set_rphi_search_window_lyr1(0.2);
./common/Trkr_TruthReco.C: mm_match->set_rphi_search_window_lyr1(0.4);
./TrackingProduction/Fun4All_FullReconstruction.C: 
mm_match->set_rphi_search_window_lyr1(3.);
./TrackingProduction/Fun4All_ZFAllTrackers.C: 
mm_match->set_rphi_search_window_lyr1(0.4);
./TrackingProduction/Fun4All_FieldOnAllTrackersCalos.C: 
mm_match->set_rphi_search_window_lyr1(0.4);
./TrackingProduction/Fun4All_TrackSeeding.C: 
mm_match->set_rphi_search_window_lyr1(3.);
./calibrations/tpc/TpcDVCalib/Fun4All_FieldOnAllTrackersCalos.C: 
mm_match->set_rphi_search_window_lyr1(0.4);

So three different values, assigned at 11 different places. It is very 
difficult to know which one is used by one.

The ones commited yesterday in Fun4All_ZFAllTrackers are not the correct one.

I will move forward and make all the values consistent and consistent with 
what they should be with real pp data (3cm) and commit.

Another thing which I noticed:

in Tracking_Reco_TrackSeed_ZeroField and elsewhere (from
common/Trkr_Reco.C) there are some parameters assigned to the ca_seeder and 
simplekfprop which depend on the gas mixture in the TPC, 
G4TPC::TPC_GAS_MIXTURE

I don't know how critical those are, but as much as I can tell, this variable 
is assigned to

./common/G4_TrkrVariables.C:  std::string TPC_GAS_MIXTURE = "NeCF4";

and never overwritten.

All in all I think one of the objectives of the workfest could be to make 
sure that our tracking parameters make sense and are consistent everywhere, 
in the repository and among users. Otherwise, it makes it very difficult to 
draw any conclusion about anything.

Opinion ?

Hugo