sPHENIX discussion of software

["Huang, Jin" <jhuang AT bnl.gov>]

Also available on agenda page: https://indico.bnl.gov/conferenceDisplay.py?confId=1925

 

 

B-tagging with displaced vertex: Sanghoon Lim

 

Summary: first purity VS efficiency plot, simulated with standard simulation setup from tracking review.

 

Slide 2: setup and K0 rejections

Jin: suggest running HFJetTruthTrigger in trigger mode with MB Pythia generator to gather b-jet sample (HFJetTruthTrigger::set_rejection_action(Fun4AllReturnCodes:: Fun4AllReturnCodes) and place the trigger module between Pythia and Geant4 part ).

 

Slide 3: Rejection VS efficiency curve

Jin: What is the impact of applying the track quality cut on the B-tagging efficiency?

Sanghoon: very smaller effect in loss of efficiency, but rejection had major improvement

 

Slide 4: Purity VS efficiency curve

Jin: What is the structure at low b-jet efficiency?

Sanghoon: suspect caused by low statistics fluctuation. Running more statistics

 

Martin: Any way to make purity even higher at sacrifice of more b-jet efficiency, e.g.  cut on kinematics distribution.

Jin: Also suggest to look at kinematic variable of vertex pT / jet pT, and secondary vertex mass. Not only for improve purity with cut, but also for template fit to measure purity with data.

 

 

Documentation

 

Jin: After development settles, please complete documentation.

·       Update wiki b-tagging note:  https://wiki.bnl.gov/sPHENIX/index.php/HF-Jet/Secondary_vertex_tagger   (contact John Haggerty for write permission account)

·       Upload analysis code to GitHub:  https://github.com/sPHENIX-Collaboration/analysis/tree/master/HF-Jet

 

Marzia: where to put official analysis notes beyond the quick wiki notes?  

Jin: Currently, we have sPHENIX documentation database (sPHENIX wiki -> Document database. Usename/password for both wiki and docDB is sphenix/babar1008)

 

 

B-tagging with Track counting algorithm: Haiwang Yu

 

Summary: final p+p plots proposed for tracking review simulation talk

 

Slide 4: Fast sim VS G4 comparison.

Jin: extra caveats for the comparison: fast sim using DCA from HIJING while analyzing pythia truth event in p+p, while the new Geant4 result simulates and analyze p+p data. Therefore, results not complete comparable  

 

Slide 6: slight degradation of performance with the intermediate tracker (IT) observed.

Secondary vertex method as in Sanghoon’s talk provides comparable performance with 2-track counting method.

 

Slide 7 - 9: Further trace down the difference from inclusion of IT

Trace the difference with/without IT to high DCA tail with IT, with inclusive DCA in jet, while Bottom jet looks very similar

 

Action Item [Haiwang]: update slides with legend for slide 7-9 

 

Slide 10: Although Gaku showed in tracking meeting, not much more tail was observed for b-b PYTHIA events.

Martin: ratio plot may be useful rather than overlay between two DCA curves.

Haiwang, Jin: Further difference in setup between Gaku’s DCA plot and Haiwang’s DCA plots: 1) inclusive track VS in-jet tracks; 2) b-bar events VS light jet events.

 

Martin: suggest document cuts detail in wiki so comparable.

Jin: Wikipage reserved for the track counting algorithm: https://wiki.bnl.gov/sPHENIX/index.php/HF-Jet/Track_counting_tagger

 

 

 

 

 

______________________________

 

Jin HUANG

 

Brookhaven National Laboratory

Physics Department, Bldg 510 C

Upton, NY 11973-5000

 

Office: 631-344-5898

Cell:   757-604-9946

______________________________

 

From: Huang, Jin
Sent: Monday, August 29, 2016 2:08 PM
To: 'sphenix-software-l AT lists.bnl.gov' <sphenix-software-l AT lists.bnl.gov>; 'sphenix-l AT lists.bnl.gov' <sphenix-l AT lists.bnl.gov>
Subject: [2-187] sPHENIX simulation and software meeting, Tue Aug 30th, 1PM EST @ 2-187

 

Hello everyone,

 

This is a reminder for a quick sPHENIX simulation and software meeting, Tue Aug 30th, 1PM EST @ 2-187.

 

During the lunch gap of sPHENIX tracking review practice tomorrow, we plan to have this short sPHENIX simulation and software meeting to follow up with few action items from last week. Currently on agenda, Haiwang will report on the b-jet tagging based on the track counting algorithm, hopefully the final plots for use in the tracking review. Please let us know if there are other updates too.

 

The agenda page is at https://indico.bnl.gov/conferenceDisplay.py?confId=1925  , for which the common modification password is "1008"

•            For residents at BNL, we will meet at the 2-187 conference room this time (as 2-219 could be still occupied by the practice tracking review).

•            To join the Meeting via phone bridge:  https://bluejeans.com/619960505 

•            To join via Phone:

1) Dial:

        +1.408.740.7256

        +1.888.240.2560(US Toll Free)

        +1.408.317.9253(Alternate number)

        (see all numbers - http://bluejeans.com/numbers)

2) Enter Conference ID: 619960505

 

Cheers,

 

Jin

 

 

______________________________

 

Jin HUANG

 

Brookhaven National Laboratory

Physics Department, Bldg 510 C

Upton, NY 11973-5000

 

Office: 631-344-5898

Cell:   757-604-9946

______________________________