Calorimetry and Physics Performance for CD-1 · the same performance as the S310 iHCALafter proper...
Transcript of Calorimetry and Physics Performance for CD-1 · the same performance as the S310 iHCALafter proper...
Calorimetry and Physics Performance for CD‐1
J. Lajoie(taking plots from the Jet ToG)
Physics performance for CD‐1• We have always talked about physics performance in terms of the energy resolution of the full calorimetry system: • Stated in previous reviews as “better than 100%/sqrt(E) with a small constant term”
• sPHENIX UPP is “better than 150%/sqrt(E)
• New HI performance plots from Jet ToG (Dennis and the CO group)• Will give an update in Friday’s General Meeting
• Ongoing studies on ability to calibrate in p+p by Songkyo• Especially with different HCAL configurations
• What follows are my “20k‐foot” takeaways for the CD‐1 review
Takeaway #1New plots with uninstrumented Al frame in place of iHCAL. All HI analysis is at the EM energy scale.
Note that the JES does not change as the centrality changes. This means the HI reconstruction is doing a good job of subtracting the underlying event.
This indicates that we should be able to take a p+p JES calibration and understand how to extend it to HI’s.
From Jet ToG (sphenix‐l 4/24)
Takeaway #2
From Dennis (private comm.) 4/30
New plots with uninstrumented Al frame in place of iHCAL. All HI analysis is at the EM energy scale.
At large R and low jet energies the resolution is dominated by fluctuations in the underlying event. This was always the goal for the design of the calorimetry system.
At small R or large jet energies the contribution of the intrinsic energy resolution of the calorimetry system becomes dominant.
(p+p20‐25 GeV)
(HI 20‐25 GeV)
(UE)
R=0.4 0.23 0.45 0.38
R=0.2 0.26 0.32 0.19
Calibrations in p+p with gamma+jet
Songkyo has made several presentations in several simulations meetings that shows how well we can calibrate in p+pusing gamma+jet.
Section added to CDR.
Calibrated resolution is consistent with HI resolution.
Most recent simulations presentation 4/24: https://indico.bnl.gov/event/4012/
Takeaway #3
Instrumenting the Al frame looks like it gets back the same performance as the S310 iHCAL after proper calibration!
This will directly impact the performance in HI’s for small R and large jet energy.
This is the best argument we have (finally quantified) for working to instrument the Al frame (cost ~$1.2M).
Work Underway
• Dennis is working on a comparison between the old (instrumented SS310) and CD‐1 (uninstrumented Al frame) configurations• Nice sanity check
• Songkyo is working to complete the instrumented Al frame results for higher jet energies
BACKUP
Double‐Check Dennis and Songkyo