loose ITk track selection wp for 21p9

Hello,

this is to define loose ITk selection wp, such that CP groups can easily configure their track selections to avoid picking Run2 cuts, such as |eta|<2.5

Specifically, I am modifying InDetTrackSelectionTool with a wp such that (courtesy of @npetters ):

• flat cuts reflecting what we have in reconstruction. E.g 7 sihit for all eta, 400 MeV,
• make sure the eta interval is change correctly and that no pixel/sct/trt cuts are remaining that would cut out the forward region for ITk.

I have added "ITkLoose" wp accordingly & tested all compiles fine. For physics validation I ran IDPVM with setting InDetTrackSelectorTool.CutLevel = "ITkLoose" and compared this to the default IDPVM track selection (running over identical ESD events)

You can see here that my wp gets collected fine:

/afs/cern.ch/work/l/lmijovic/public/r21p9/ITkLoose/27032019
grep -i ITkloose out.out 
ToolSvc.InDetTr...   INFO Cut level set to "ITkLoose".

and in the attached plot that the "ITkLoose" is looser wrt to the default InDetTrackSelectionTool cuts r21.9 IDPVM uses. (Which indicates we should likely loosen the default IDPVM cuts, I think I know which one, but that's a IDPVM rather than loose wp issue)

What is on my todo list for this MR is the following:

• think whether I should add or modify cuts of the current ITkLoose wp
• perform more thorough testing, to be sure I am indeed keeping all reco-ed tracks
• update InDetTrackSelectionTool/test for the newly added wp

FYI @nstyles @goblirsc @npetters