STAR task force for evaluating tracking efficiency uncertainty

[Petr Chaloupka <petrchal AT rcf.rhic.bnl.gov>]

Hello Yuri,

sorry I missed the message. This sounds plausible.
I 'm wondering if I could test this.
The advantage of my analysis that I do not use the cut on primary DCA.
This allows me to take full DCA distribution. what I will try to do is to look
at the DCA depending on where the tracks end. Maybe that will show something.
Thanks for the information.

Best regards,
Petr

On 18. 06. 25 1:12, Fisyak, Yuri V wrote:

 

Hi Petr and all.

   After today’s discussion I have a thought.

In STAR geometry there is a suspicious place : Support cones (scon) which are used to support beam pipe.

These cones are located at z [50 – 230] cm and radius [20 – 40] cm from both sides of STAR,

i.e. the west cone covered for fixed target in pseudo rapidity the east ITPC region.

The effect of the cone on DCA is defined by its radiation length. In STAR geometry now the cone consists of two parts:

Cardon fiber : ~0.16 cm / RADL = 18.8 cm = 0.8%, Mylar        : ~0.10 cm /        28.5 cm = 0.3%

 

The problem is that I don’t know how well these 0.8_0.3 = 1.1% of radiation length corresponds to reality.

An other problem is that these cones radiation length is not accounted in the track reconstruction.

                                                              Yuri Fisyak

STAR                                           Phone: +1 631 344 3913
Brookhaven National Laboratory  Fax:    +1 631 344 4206
510A/1-161
http://www.star.bnl.gov/~fisyak       E-mail: fisyak AT bnl.gov

 

 

 

From: star-tf-trkeff-l-request AT lists.bnl.gov <star-tf-trkeff-l-request AT lists.bnl.gov> on behalf of Petr Chaloupka <petrchal AT rcf.rhic.bnl.gov>
Date: Monday, June 16, 2025 at 10:01 AM
To: star-tf-trkeff-l AT lists.bnl.gov <star-tf-trkeff-l AT lists.bnl.gov>
Cc: Mathias Labonte <mlabonte AT ucdavis.edu>
Subject: [[Star-tf-trkeff-l] ] Tracking Efficiency Uncertainty meeting June 17, 2025, 10:00 AM

Dear All,

let me invite you to join our meeting tomorrow at 10:00 New York time if
you have the time.

Please add any contribution you wish to discuss at:
https://drupal.star.bnl.gov/STAR/event/2025/06/17/Tracking-Efficiency-Uncertainty-meeting


With best regards,
Petr

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