Next steps for Megan

Megan showed some plots of kinematic quantities for the "raw-raw" and "raw" muonic sld MC on Friday.  These look good.

Btw, what we mean by "raw-raw" is the generated p4 and x4 quantities with x4 for the primary vertex set to (0,0,0,0).  We'll call this "generated" from now on.

The "raw" MC is the same p4 vectors, but with the primary x4 set to some position in the target with some physical event time.  The Lambda vertex (and any other decay vertices) are fixed by this, too.  This step is taken care of by hdgeant4, and all of these quantities are taken from the hddm files that hdgeant spits out.

See /w/halld-scifs17exp/home/mmccrack/mc_processing/gen_raw_vert_files for the code to generate these files.

So far, Megan has looked at 5 files worth (10k events) of this MC.

NOW it's time for Megan to start looking at some "accepted" MC files, meaning events after the detector simulation.  So!  I have to generate some files that will work for her, and align with the information that she already has.  The sld_mu raw files that she's using were generated on May 22, and I haven't generated anything new for this reaction since.

I THINK that I can get away with modifying the protonTRUTH DSelector, and then using my TTree to ascii scripts to get Megan the info that she needs.  She should get measured and KF p4, post-KF x4, AND it would be good to have the track ID for each particle (so that we can subtract out any K+ or mu decays that would screw up vertexing).  Said DSelector is here:
/w/halld-scifs17exp/home/mmccrack/dsel_protonTRUTH

Actually, I have to do some digging to figure out the track ID stuff, so I'll do that later.

My sld to ascii script is here: /Users/mmccracken/office_comp/lambda_sld/jun2019/sld_ttree_2_megan.py

ACTUALLY, I'm just going to give Megan the same files that I'm working with, but cut all events from files numbers above 1004 (i.e. remove all events with number greater than or equal to 100500000.

Megan is going to look into differences between raw and accepted MC of the following quantities:
beam photons: energy
K+: px, py, pz, magnitude of p, energy
proton: same as K+
mu-: same as K+
primary vertex: x, y, z, t, and distance between raw and accepted vertex
Lambda (secondary) vertex: same as primary vertex.

For now, Megan will use the kinfit quantities in the accepted files.

Files are on Google Drive:
kL_acc_fastpi_1000-1004.ascii
kL_acc_ppim_1000-1004.ascii
kL_acc_sl_mu_1000-1004.ascii