RICH upgrade simulation: updates S.Easo RICH upgrade-mechanics meeting 1

 PID results : cross-checking with different software versions Outline 2 LHCb tracking PID tuning

LHCb Tracking (TDR studies): No ‘upgrade tracking’ available for RICH studies Used current LHCb tracking geometry + different versions of RICH upgrade geometry Not a perfect, but a practical solution at the time.  2014 : ‘Upgrade tracking’ became available, so started using it for RICH Feb : Upgrade/current tracking comparisons in terms of PID. Track quality parameters were not available. So assumed all long tracks are ‘good tracks’ as a first step.  2015 : Track ghost probability parameter available, Used this to filter the upgrade tracks used for RICH.  This talk: PID with some of the above tracking setups. They all use same PYTHIA (generator) and beam configurations. So expect only minor variations of performance among them. RICH performance depends on the tracks input to RICH. 3

Simulation Configuration  Gauss v47r0p1, Boole 29r3, Brunel v47r4  Tracking : Recent version as in Brunel v47r4 for upgrade/current LHCb  Luminosity : Lumi20 ( 2X cm 2 s -1 ), no spillover  B s   events  RICH Optics: 4 ROC 3800 mm, 3600 mm, 3650 mm With/without photon plane shift of 100 mm. Current standard setup in software: ROC 3800mm, no plane shift RICH2 : large+ small pmts  PID Tuning: Current/Old tuning. Current tuning is default.

Red: Upgrade LHCb Tracking + Tracks selected with ghost probability cut Blue: Upgrade LHCb Tracking + All tracks Black: Current LHCb Tracking + Tracks selected with ghost probability cut PID from Upgrade LHCb tracking improved compared to that from Current LHCb tracking RICH1: standard setup 5 Same relative performances obtained with different RICH optics setup also.

6 Upgrade tracking, ghost probability< 0.3 Red: RICH1 ROC 3800 mm Black: RICH1 ROC 3800 mm, photon plane shift 100 mm Blue: RICH1 ROC 3600mm, photon plane shift 100 mm Cyan : RICH1 ROC 3650 mm, photon plane shift 100 mm Effect from photon plane shift recovered by change in ROC

7 Current LHCb tracking Red: RICH1 ROC 3800 mm Black: RICH1 ROC 3800 mm, photon plane shift 100 mm Blue: RICH1 ROC 3600mm, photon plane shift 100 mm Upgrade tracking, : All tracks Effect from photon plane shift recovered by change in ROC This conclusion on optics obtained, independent of the tracking used.

8 Optics and PID tuning : Upgrade LHCb Tracking Upgrade LHCb Tracking, Current PID Tuning Upgrade LHCb Tracking Old PID Tuning Effect from photon plane shift recovered by change in ROC This conclusion on optics obtained, is independent of the PID tuning used with Upgrade LHCb tracking or Current LHCb Tracking. (Similar plots obtained from Current LHCb Tracking ). Red: RICH1 ROC 3800 mm Black: RICH1 ROC 3800 mm, photon plane shift 100 mm Blue: RICH1 ROC 3600mm, photon plane shift 100 mm

9 SUMMARY and PLANS  Using latest version of software for RICH upgrade.  Various cross-checks made with previous versions and results look consistent with each other.  Plans Flat mirror size tune Long term: Rebuild the PMT array with Elementary cells.

BACKUP SLIDES 10

Effects from PID tuning Some tuning done in 2013 Now re-visiting with current versions For illustration use tracks with 7.5 < P < 100 GeV/c on this page. Blue: Current tuning Magenta: Old Tuning All Plots:RICH1 ROC=3800 mm using upgrade tracking Top Plot: Standard setup, no shift in photon plane Bottom plot: Photon plane shift=100 mm Tuning gave a small improvement in PID performance in both plots

12 PID vs Momentum Upgrade tracking, ghost probability <0.3 RICH standard setup (ROC 3800 mm) Current LHCb tracking, ghost probability <0.3 RICH standard setup (ROC 3800 mm)

13 Optics and PID tuning : Current LHCb Tracking Current LHCb Tracking, Current PID Tuning Current LHCb Tracking Old PID Tuning Effect from photon plane shift recovered by change in ROC This conclusion on optics obtained, is independent of the PID tuning used with Current LHCb tracking Red: RICH1 ROC 3800 mm Black: RICH1 ROC 3800 mm, photon plane shift 100 mm Blue: RICH1 ROC 3600mm, photon plane shift 100 mm