sPHENIX tracking discussion

["Kimelman, Benjamin" <benjamin.kimelman AT Vanderbilt.Edu>]

Here it is for just one stripe. The NN method is stable at all pedestal subtraction thresholds, while the fancy method is stable after a pedestal subtraction threshold of 20.

Benjamin Kimelman Postdoctoral Scholar, Dept. of Physics & Astronomy Vanderbilt University benjamin.kimelman AT vanderbilt.edu Pronouns: He/him/his

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From: Ross Corliss <ross.corliss AT stonybrook.edu>
Sent: Friday, August 9, 2024 10:00 AM
To: Kimelman, Benjamin <benjamin.kimelman AT Vanderbilt.Edu>
Cc: Christof Roland <Christof.Roland AT cern.ch>; Osborn, Joseph via sPHENIX-tracking-l <sphenix-tracking-l AT lists.bnl.gov>
Subject: Re: [[Sphenix-tracking-l] ] CM Distortion Matching Schemes

 

Hi Ben,

Cool to see the uniformity, but as drawn it could still be that the stripes are all randomly jumping around within this band.  Could you generate this for /one/ CM stripe?  Or a small number of representative ones from different areas of the detector?

-Ross

==========
Dr. Ross Corliss
Research Assistant Professor
Center for Frontiers in Nuclear Science
Stony Brook University
virtual office:  https://stonybrook.zoom.us/my/rossoffice?pwd=ZmZ2SlRIMVFvUUJwbUkyOVNVTmE5QT09

On Aug 9, 2024, at 10:54 AM, Kimelman, Benjamin <benjamin.kimelman AT Vanderbilt.Edu> wrote:

Hi all,

Attached are distributions of the radial distortion and phi distortion against the event number which shows that these are pretty stable with time. I was not able to quickly find the laser flash frequency though.

Best,

Benjamin Kimelman Postdoctoral Scholar, Dept. of Physics & Astronomy Vanderbilt University benjamin.kimelman AT vanderbilt.edu Pronouns: He/him/his

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From: Christof Roland <Christof.Roland AT cern.ch>
Sent: Friday, August 9, 2024 7:25 AM
To: ross.corliss AT stonybrook.edu <ross.corliss AT stonybrook.edu>
Cc: Kimelman, Benjamin <benjamin.kimelman AT vanderbilt.edu>; Osborn, Joseph via sPHENIX-tracking-l <sphenix-tracking-l AT lists.bnl.gov>
Subject: Re: [[Sphenix-tracking-l] ] CM Distortion Matching Schemes

 

You don't often get email from christof.roland AT cern.ch. Learn why this is important

Hi Ben, 

I agree with Ross, A plot of mean and variance across the accessible x-y coordinates of the detector would be nice. 

Also I think it would be good to see the time sequence for on matching position. Is the (supstantial) spread in r and phi this a random resolution effect or do we really see fluctuations...

Currently the spread in R and phi is on the order of a few millimeters and R at least is also a strong function of threshold. 

On the scale of O(150um) we want to achieve we need to understand this better. 

Cheers

   Christof 

On 8. Aug 2024, at 21:53, Ross Corliss <sphenix-tracking-l AT lists.bnl.gov> wrote:

Thanks for sharing this! 

So is the dr dphi spread a real effect of different places in the detector? Your spot-check of #1600 certainly hints that could be the case. A plot of distribution mean, and one of variance, as a function of (r, phi) position would give a compact way to visualize whether you are seeing weird artifacts, or a smooth map of the distortion. 

- Ross

On Thu, Aug 8, 2024, 14:20 "Kimelman, Benjamin" <sphenix-tracking-l AT lists.bnl.gov> wrote:

Hi all,

I've put together some slides following up on the figures I showed today about changing to a nearest neighbor matching scheme. I've zoomed in as Christof suggested and also selected on just a single truth position as Ross suggested (I selected on truthIndex 1600, which is petal 0, row 16, phi 0). These clearly show that the NN scheme is more robust and gives better performance.

My slides don't include every histogram from all pedestal subtraction thresholds, so I'm including files that have those as well.

Let me know if you have any questions or feedback.

Benjamin Kimelman Postdoctoral Scholar, Dept. of Physics & Astronomy Vanderbilt University benjamin.kimelman AT vanderbilt.edu Pronouns: He/him/his

<fancyComparison_eventPhi.pdf><fancyComparison_eventR.pdf>

Attachment: fancyComparison_eventPhi1600.pdf
Description: fancyComparison_eventPhi1600.pdf

Attachment: fancyComparison_eventR1600.pdf
Description: fancyComparison_eventR1600.pdf