sPHENIX discussion of physics

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

Announcement: we will move the next meeting from 7PM ET to 8PM ET due to conflict with a few members. Please let us know if there is a strong objection. 

 

 

b-jet tagging - Daniel Liz (UC Boulder)

Chat at: https://chat.sdcc.bnl.gov/sphenix/channels/hf-jet-tc-tagger 

 

Summary: getting familiar with the 2017 code and upgrade it to be compatible with the current software. Looking into repeating the 2017 study then move on to building the MVA based b-jet tagging

 

Jin: This is a very good time to reproduce the jet simulation sample as the MDC1 macro and build provide a stable simulation environment. 

 

Jin: much more variable can be used in the MVA tool inputs such as DCAxy, DCAz, DCA sigma, track kinematics, 2ndary vertex's composition, distance, and secondary vertex mass. 

 

Yen-Jie: when used with an orthogonal tagger, a b-jet 2nd vertex mass provides a valuable tool to get data-driven efficiency and purity.

Sanghoon: p

Sanghoon/Jin: produced the invariant mass spectrum in the 2017 study [sPH-HF-2017-001]. However, we did not emulate purity a study at that time. 

 

 

Updates on MDC1 status - Cameron Dean (LANL)

Chat at: https://chat.sdcc.bnl.gov/sphenix/channels/hf-mdc1 

 

Please take a look at the test production: 

/sphenix/user/cdean/MDC1/pythia8/HeavyFlavorTG/data/

 

Cameron: Most recently, fixed one rare bug. Continues test production with the coming MDC1.5 build. 

 

Ming: is that possible to produce jet-KFParticle matching?

Cameron: possible to match KFParticle objects and Jet, or feed tracks that are associated with a jet into KFparticle. 

Example in advanced tutorial example for KFParticle: 

• Use an arbitrary set of vertex input: https://github.com/sPHENIX-Collaboration/analysis/blob/master/HF-Particle/KFParticle_sPHENIX/Fun4All_KFParticle_advanced.C#L178 
• Use an arbitrary set of track input: https://github.com/sPHENIX-Collaboration/coresoftware/blob/master/offline/packages/KFParticle_sPHENIX/KFParticle_sPHENIX.h#L215

 

 

B_s update - Zhaozhong Shi (MIT)

Chat at: https://chat.sdcc.bnl.gov/sphenix/channels/hf-bs  

 

Slide 2: tracking eff. not included yet, which is important for four-track final states. 

 

Slide 5: dNch/deta to centrality mapping

Yenjie/Jin: please use dNch/deta from Phobos for centrality mapping: 

https://arxiv.org/abs/1011.1940 

Yenjie: what is the input p_T spectrum?

Zhaozhong: inherited from L_c analysis

 

Slide 7: 

Yenjie: please add correlation of BDT output and B_s mass

 

Slide 8: 

Hideki: 1-eff. on y-axis

 

Slide 9: 

Zhaozhong: TMVA splitting sample for training and testing

 

Slide 14: 

Yen-Jie DCA distribution so different from pi+ and pi-, and pT spectrum. Please double-check background sample distribution

Jin: please also double-check the B_s and B_s_bar assumptions in the background selection.

Zhaozhong (post-meeting chat on MatterMost): Only D_s^- used in background pre-section which biased pi+ and pi- spectrum.  

 

Slide 10: 

Jin: need to define and use the same luminosity and centrality ranges for signal and background

 

Yenjie: correlated background can be quite important, e.g. via B_c/L_b decay chains. 

Jin: MDC1 data will provide 30/pb inclusive b background

Zhaozhong: this is the starting point for possibility study concerning combinatorial only

 

 

 

 

 

______________________________

 

Jin HUANG

 

Physicist, Ph.D.

Brookhaven National Laboratory

Physics Department, Bldg 510 C

Upton, NY 11973-5000

 

Office: 631-344-5898

Cell:   757-604-9946

______________________________

 

From: Huang, Jin
Sent: Saturday, January 23, 2021 2:30 PM
To: sphenix-hf-jets-l AT lists.bnl.gov
Cc: sphenix-maps-l AT lists.bnl.gov; Daniel.Lis AT colorado.edu; Perepelitsa, Dennis <dvp AT bnl.gov>; sphenix-physics-l AT lists.bnl.gov
Subject: [Jan 25 Monday 7PM ET] bi-weekly heavy flavor topical group meeting

 

Hi Everyone,

 

This is a reminder that we will have our next HF topical group meeting on Jan 25 Monday 7PM ET.  

 

On the agenda:

 

• Quick update on MDC1 status by Cameron Dean
• First report on b-jet studies from Daniel Lis
• B_s update by Zhaozhong Shi

 

Please join us via

 

• Indico: https://indico.bnl.gov/event/10631/
• ZOOM connection: https://bnl.zoomgov.com/j/1613938007?pwd=QjYzUnpYQ2xNZWZLSy9qd3Z4dFpzZz09

 

We look forward to talking to you all at the meeting.

 

Best regards,

 

Hideki & Jin

 

 

 

______________________________

 

Jin HUANG

 

Physicist, Ph.D.

Brookhaven National Laboratory

Physics Department, Bldg 510 C

Upton, NY 11973-5000

 

Office: 631-344-5898

Cell:   757-604-9946

______________________________

 

From: Huang, Jin
Sent: Friday, January 15, 2021 12:37 PM
To: sphenix-hf-jets-l AT lists.bnl.gov
Cc: sphenix-maps-l AT lists.bnl.gov
Subject: [One week shift: Jan 25 Mon 7PM ET] bi-weekly heavy flavor TG meeting

 

Hi Everyone

 

The coming Monday is US Federal holiday. So we will shift the biweekly schedule by one week and meet on Jan 25 7PM ET:

https://indico.bnl.gov/event/10631/

Meanwhile, the Mattermost channels are always open: https://wiki.bnl.gov/sPHENIX/index.php/Heavy_Flavor_Topical_Group#MatterMost_Chats

 

Talk to you in the collaboration meeting

 

Cheers

 

Jin & Hideki

 

 

______________________________

 

Jin HUANG

 

Physicist, Ph.D.

Brookhaven National Laboratory

Physics Department, Bldg 510 C

Upton, NY 11973-5000

 

Office: 631-344-5898

Cell:   757-604-9946

______________________________

 

From: sPHENIX-l <sphenix-l-bounces AT lists.bnl.gov> On Behalf Of Hideki Okawa
Sent: Monday, January 4, 2021 7:56 AM
To: sphenix-hf-jets-l AT lists.bnl.gov
Cc: sphenix-l AT lists.bnl.gov; sphenix-maps-l AT lists.bnl.gov
Subject: Re: [Sphenix-l] [Jan 4 Mon 7PM ET] bi-weekly heavy flavor TG meeting

 

Dear all,

 

Happy New Year!

 

This is a kind reminder for our topical group

meeting today at 7PM ET.

 

We will hear updates on:

- MDC1 status (Cameron Dean)

- B_s studies (Zhaozhong Shi)

 

Talk to you then!

 

Best regards,

Jin & Hideki

 

 

---

From: Hideki Okawa
Sent: Tuesday, December 29, 2020 11:13
To: sphenix-hf-jets-l AT lists.bnl.gov
Cc: sphenix-maps-l AT lists.bnl.gov; sphenix-l AT lists.bnl.gov
Subject: [Jan 4 Mon 7PM ET] bi-weekly heavy flavor TG meeting

Dear all,

 

It turned out that the current meeting time is

still optimal after collecting the doodle poll.

 

Our first meeting for 2021 will be on Jan. 4

Monday at 7PM ET!

 

We will hear updates on MDC-1 status from

Cameron Dean.

 

Please join us via:
Indico: https://indico.bnl.gov/event/10386/ 

Zoom: https://bnl.zoomgov.com/j/1613938007?pwd=QjYzUnpYQ2xNZWZLSy9qd3Z4dFpzZz09

 

We wish all nice winter holidays and a happy

new year!

 

Talk to you all at the meeting.

 

Best regards,

Jin & Hideki