sPHENIX tracking discussion

[Anthony Frawley <frawley AT fsunuc.physics.fsu.edu>]

Hi Hugo,

----------------------

Alpha, beta and gamma are the angle from the surface normal vector to the global x, y and z axis, is that correct ? So if I want to make a polar (in x,y plane) rotation of the surface of value phi I should use

alpha = +phi

beta = phi – pi/2

gamma = 0  ?

 

Or do I get the signs mixed up

--------------------------

Alpha, beta and gamma are the rotation angles in local coordinates, prior to the rotation and translation that places the surface in global coordinates. They do not change (in global coordinates) the phi angle of the surface center. Alpha, beta and gamma just change the direction of the surface normal vector.

So it depends on what you want to do. If you want to rotate the surface around the z axis (for example) in global coordinates, there is a third set of rotations that do that (presently all set to zero by default). If you look at

offline/packages/trackbase/AlignmentTransformation.cc

you will see how these are applied.

I can chat on zoom if you would like.

Tony

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From: sphenix-tracking-l-request AT lists.bnl.gov <sphenix-tracking-l-request AT lists.bnl.gov> on behalf of "Pereira Da Costa, Hugo Denis Antonio" <sphenix-tracking-l AT lists.bnl.gov>
Sent: Friday, August 16, 2024 1:13 PM
To: Anthony Frawley <frawley AT fsunuc.physics.fsu.edu>; Hugo Pereira Da Costa <hugo.pereira.da.costa AT gmail.com>; Osborn, Joe <osbornjd AT ornl.gov>; Christof Roland <christof.roland AT cern.ch>; sphenix-tracking-l AT lists.bnl.gov <sphenix-tracking-l AT lists.bnl.gov>
Subject: RE: [[Sphenix-tracking-l] ] Follow up on today's slides

 

Hi Tony,

 

I have started to play around with local alignment parameters and in particular rotations.

 

Just making sure I got the convention right:

In the email below:

Alpha, beta and gamma are the angle from the surface normal vector to the global x, y and z axis, is that correct ? So if I want to make a polar (in x,y plane) rotation of the surface of value phi I should use

alpha = +phi

beta = phi – pi/2

gamma = 0  ?

 

Or do I get the signs mixed up ?

 

Thank you,

 

Hugo

 

From: Anthony Frawley <frawley AT fsunuc.physics.fsu.edu>
Sent: Thursday, August 8, 2024 1:32 PM
To: Hugo Pereira Da Costa <hugo.pereira.da.costa AT gmail.com>; Osborn, Joe <osbornjd AT ornl.gov>; Christof Roland <christof.roland AT cern.ch>; sphenix-tracking-l AT lists.bnl.gov
Cc: Pereira Da Costa, Hugo Denis Antonio <hugo.pereira-da-costa AT lanl.gov>
Subject: [EXTERNAL] Re: Follow up on today's slides

 

Hi Hugo,

 

The easiest way to do 3) is to edit a copy of the current alignment parameters file to change the TPOT values.

 

If you can download the CDB version that would be best.

 

Otherwise:

 

I am on an airplane right now, with close to useless internet speed, so I am working from memory, and the details here are approximate. 

 

Look in my directory 

/sphenix/user/frawley/production/macros/TrackingProduction/

 

There are some files "xxx_localAlignmentParamsFile.txt. The latest one is what is in the CDB. Copy that over to your working directory, rename it "localAlignmentParamsFile.txt" and edit the lines starting with TPOT hitsetkeys. The format is:

 

hitsetkey  dalpha dbeta  dgamma dx dy dz

 

in radians and mm.

 

Cheers

Tony

 

 

---

From: Hugo Pereira Da Costa <hugo.pereira.da.costa AT gmail.com>
Sent: Thursday, August 8, 2024 1:37 PM
To: Osborn, Joe <osbornjd AT ornl.gov>; Christof Roland <christof.roland AT cern.ch>; Anthony Frawley <frawley AT fsunuc.physics.fsu.edu>; sphenix-tracking-l AT lists.bnl.gov <sphenix-tracking-l AT lists.bnl.gov>
Cc: Hugo Pereira Da Costa <hugo.pereira-da-costa AT lanl.gov>
Subject: Follow up on today's slides

 

Joe, Christof, others,

1/ the CDB tag I use in the reconstruction macro is the one I got from Tony:


   // condition database
   Enable::CDB = true;
   rc->set_StringFlag("CDB_GLOBALTAG", "ProdA_2024");
   rc->set_uint64Flag("TIMESTAMP", 6);

   // tracking geometry
   std::string geofile =
CDBInterface::instance()->getUrl("Tracking_Geometry");
   auto ingeo = new Fun4AllRunNodeInputManager("GeoIn");
   ingeo->AddFile(geofile);
   se->registerInputManager(ingeo);

Is this the correct one ?

2/ to Christof: I have updated the slides I posted at
https://nam04.safelinks.protection.outlook.com/?url="https%3A%2F%2Findico.bnl.gov%2Fevent%2F24192%2Fcontributions%2F95299%2Fattachments%2F56417%2F96569%2FTpcResiduals_hp.pdf&data=05%7C02%7Cfrawley%40fsunuc.physics.fsu.edu%7C4754271da8d24546ac3408dcb7d0d062%7Ca36450ebdb0642a78d1b026719f701e3%7C0%7C0%7C638587355126212973%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=WuPrR92EVWLfAWCAsBND1Wb6aLQ5o8Usew1IUDhLe0M%3D&reserved=0
to look in more detail at delta_phi vs layer with charge cut. This is in
slide 9.

There is a charge dependnece when getting near TPOT, and since each
charge tends to favor one sector rather than the other, this would point
to a sector dependent phi misalignment in TPOT, as you hinted during the
meeting.

3/ Any help about how to add per-layer delta phi (and delta_z) alignment
offsets via text file would be very appreciated ! (Tony ? Joe ?)

Best,


Hugo