sPHENIX discussion of physics

[Cameron Thomas Dean <cameron.dean AT cern.ch>]

Hi all,

Here are the minutes of today’s meeting.

Cheers,

Cameron

Introduction - Conveners

Cameron - RHIC cooldown is expected to begin on May 1st

Jin - We have completed our simulation prodction. The D0-jet sample has produced lots of discussion and we have 50M min-bias pp events

Xuan - We have found an issue with the D0-jet sample. With the low pT (event tag 17), we were unable to link truth and reco variables. It could be a sync issue as we saw reco quantities

Antonio - I can look into this.

Hard Probes 2023 summary - Antonio da Silva

Slide 3 - Cameron - For the D0-D0bar separation from ALICE, did they indicate how they separated the two states? Was it K+pi- / K-pi+ invaraint masses?

Antonio - I believe so. They can take advantage of their PID for this.

Slide 4 - Jin - Thank you for the summary and for representing sPHENIX at HP23. For the J/psi results, do we have an initial study which would indicate our low pT reach in this channel?

Marzia - Sasha Lebedev has looked into this with pion background to represent AuAu collisions. Below 5 GeV, it is very hard to see a peak. We may get better electron ID with MVA techniques and get down to 4 GeV but I don't think we can get as low as 2 GeV as the background is very high.

Jin - That makes a lot of sense to me.

Slide 9 - Jin - Was there a quantitative discussion on b-hadrons as to how much of a contribution can be from coalesence in the strnage/non-strange R_AA ratio? 

Antonio - I don't recall there being such a discussion

Jin - As b-quark is heavier than the c-quark, I would imagine it would be a larger contribution

Slide 10 - Xuan - You mentioned the red panel is integrated over pT but the left panel has different pT ranges for differnet results, is the full pT range accounted for, down to 0 GeV?

Antonio - Yes, there is an extrapolation to 0 GeV to account for this.

Slide 11 - Jin - Is there an update from ALICE on D-D correlations?

Antonio - I haven't seen one. It may be ongoing.

Slide 13 - Xuan - How is the theta angle defined? Does it use any particle within the angle?

Antonio - You have requirements on the k_T (see top right)

Xuan - We can consider some grroming.

Antonio - Here there is no grooming. There are some other cuts we can consider but we have to be careful.

Xuan - For D0-jets, you need two measurements. One for the D0-jets and another on inclusive jets to act as a weighting factor. For inclusive jets, we have to rely on the calorimeters while for D0-jets, we can use the tracking information as well.

Antonio - We could also use D0-jets in AuAu and pp and use that as the reference sample.

On Apr 7, 2023, at 12:16 PM, Cameron Dean <cameron.dean AT cern.ch> wrote:

Hi all, 

This is a reminder that we will meet in a few hours, at 3pm ET. 

We look forwarding to meeting everyone soon,

Tony, Cameron, Jin and Marzia

Begin forwarded message:

From: Cameron Dean <cdean AT bnl.gov>

Subject: Next joint heavy flavor and quarkonium meeting, 04/07/23

Date: April 5, 2023 at 10:45:27 AM EDT

To: sphenix-upsilon-l AT lists.bnl.gov, sphenix-physics-l AT lists.bnl.gov, "Huang, Jin via sPHENIX-HF-jets-l" <sphenix-hf-jets-l AT lists.bnl.gov>

Dear heavy flavor and quarkonia enthusiasts, 

We will have the next joint TG meeting this Friday (04/07) at 3pm ET. The agenda is currently:

• Introduction - Conveners
• Hard Probes 2023 summary - Antonio da Silva (Iowa State)

The indigo agenda can be found at https://indico.bnl.gov/event/18988/

The zoom link is https://bnl.zoomgov.com/j/1613938007?pwd=QjYzUnpYQ2xNZWZLSy9qd3Z4dFpzZz09 

We look forward to talking to everyone on Friday.

Cheers,

Tony, Cameron, Jin and Marzia