sPHENIX MAPS tracker discussion

[Anthony Frawley <afrawley AT fsu.edu>]

Hi All,

Looking at tracking results for 100 pion events using the new INTT setup, I find that the tracker fails almost completely to associate the hits in the vertical strips with tracks (I saw 5 tracks out of 1000 where the vertical strip hit was associated with a track).

Looking into this using some ntuples I made (where the vertical strips are in layer 3, the first INTT layer):

/sphenix/user/frawley/fresh_macros_june26/macros/macros/g4simulations/eval_output_100pions_newINTT/

g4svtx_eval_*.root_g4svtx_eval.root

I realized the following:

1) For horizontal strips, x and y are both well defined, while z is taken as the center of a strip of length 2 cm or so. This means that the radius is well defined by the precise space point in (x,y), and z is unknown.

2) For strips aligned in phi, only z is well defined. Both x and y vary along the length of the strip. So the radius is calculated using the values of x and y at the center of the strip, and is in general not correct. Thus the precise definition of z is associated with  a not very precise radius value.

Is that a problem for tracking?

Tony

---

From: Christof E Roland <cer AT mit.edu>
Sent: Tuesday, July 24, 2018 10:04 AM
To: sphenix-maps-l
Cc: Ross Corliss; Todoroki, Takahito; Carlos Perez; Anthony Frawley; Chiu, Mickey; sanghoon.lim AT colorado.edu; mitay AT umich.edu; Mickey Chiu; sphenix-intt-l AT lists.bnl.gov; Huang, Jin
Subject: Next Meeting of the Inner Tracker Task Force

 

Hi Everybody,

we will have the next meeting of the inner tracker task force tomorrow, Wednesday at 9am EST.
The corresponding indico with the vidyo link and the link can be found here:

https://urldefense.proofpoint.com/v2/url?u=https-3A__indico.bnl.gov_event_4874_&d=DwIFAg&c=HPMtquzZjKY31rtkyGRFnQ&r=O5IMywjiKCp6dNXW0Blu_Q&m=Bm18hCpf1tVsyH4X2QNVZCtsYTdEbYlKTthM0PTb5xw&s=uC2H3sMJYWmZyMHp5dJmOlqkhYBp5z-mHKunovYRlYM&e=

Inner Tracker Task Force Meeting (25 July 2018) · Indico

urldefense.proofpoint.com

https://bluejeans.com/553808487/ https://docs.google.com/document/d/17PJdu94Ydg25V-cTHIYfSbkfojH4ZUEfsfoZPm0RDb0/edit  

The link to the google doc with the task lists and work assignments can be found here:

https://urldefense.proofpoint.com/v2/url?u=https-3A__docs.google.com_document_d_17PJdu94Ydg25V-2DcTHIYfSbkfojH4ZUEfsfoZPm0RDb0_edit&d=DwIFAg&c=HPMtquzZjKY31rtkyGRFnQ&r=O5IMywjiKCp6dNXW0Blu_Q&m=Bm18hCpf1tVsyH4X2QNVZCtsYTdEbYlKTthM0PTb5xw&s=-4ylu6_qnM0y1BPOyfqGFK8Fbred4xU7e06H_MWb3W8&e=

Please have a close look at the google doc and make sure that all items related to the task
are included.

See you tomorrow

   Christof Roland