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CEPC tracking studies

This wiki describe track resolution studies using 2 designs with different outer tracker radius. The plots are done assuming flat distribution of single muons in |y|<3.

Tracker using B=3T and R=1.25m

Here is a short description on how to check track resolution using CEPC-sidcc2 detector which has the SiD envelope for tracking (R=1.25 m), 25 um pitch size and 3 Tesla field. The data are taken from rfull101 dataset list.

Here are the steps to check the resolution using single muons. You will need this script cepc_track_resolution.py and the input dataset pgun_muon_eta3_pt150gev

bash   #  set bash if you haven't done this before, and make sure Java is installed. 
wget http://atlaswww.hep.anl.gov/asc/jas4pp/download/current.php -O jas4pp.tgz
tar -zvxf jas4pp.tgz
source jas4pp/setup.sh # takes 5 sec for first-time optimization
hs-get pgun_muon_eta3_pt150gev%rfull101 data 2 500 # get 500 files in 2 threads
# download the python script shown above and run it as
fpad cepc_track_resolution.py

This script calculates the tracking resolution of this detector as shown below:

Here is the script that does sigma(1/pt). cepc_track_resolution_overpt.py

The calculated values are:

Click to display ⇲

Click to hide ⇱

#  X       Y     ErrorX-      ErrorY+       ErrorY-      ErrorY+ 
10.146249520505538 7.233707688030497E-4 5.704907825633882 5.704907825633882 8.502371007125989E-6 8.502371007125989E-6
29.97624545765604 2.4885582068389435E-4 5.78713865684815 5.78713865684815 2.7299775405151286E-6 2.7299775405151286E-6
49.954003533114985 1.4832996719960168E-4 5.769439544642645 5.769439544642645 1.5468566955835806E-6 1.5468566955835806E-6
69.93649191232116 1.0747555580737206E-4 5.73788457385378 5.73788457385378 1.207919858957492E-6 1.207919858957492E-6
89.98736169597974 8.74971031060202E-5 5.7789623998936674 5.7789623998936674 9.720552302933245E-7 9.720552302933245E-7
109.9722327265809 7.276974424666559E-5 5.785881825564851 5.785881825564851 8.011527768175124E-7 8.011527768175124E-7
130.00571018130168 6.643313435056274E-5 5.738190270370251 5.738190270370251 7.232826222201539E-7 7.232826222201539E-7

Tracker using B=3T and R=1.8m

A new CEPC-Si detector was created using B=3 and R=1.8m tracker, which can fits to the envelope of CEPC-ILD detector, The new detector, called CEPC-sidcc3, with modified tracker was used to create rfull102 dataset list.

The analysis of this data can be done exactly as before. The only difference is that you will need to download the different dataset:

hs-get pgun_muon_eta3_pt150gev%rfull102 data 2 500 # get 500 files in 2 threads

The track resolutions are shown in

Tracking in different Theta regions

As before, this was done using B=3 and R=1.8m tracker and CEPC-sidcc3.

Data files are:

cepc_track_resolution_overpt_barrel.jdat

cepc_track_resolution_overpt_endcap.jdat

The results are created with the scripts:

cepc_track_resolution_overpt_barrel.py

cepc_track_resolution_overpt_endcap.py

Sergei Chekanov 2017/09/07 17:04