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RICH upgrade simulation: updates

11-2-2015

RICH upgrade-software meeting

S.Easo

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Updates from LHCb tracking , PID algorithm

RICH 1 Optics : Fine tuning spherical mirror ROC

Plans : Evolutions of MAPMT array configurations

Outline

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LHCb Tracking

• 2012-13 (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. 2014 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 PID performance among them.

• RICH performance depends on the tracks input to RICH.

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Simulation Configuration

Gauss v47r0p1, Boole 29r3, Brunel v47r4

Tracking : Recent version as in Brunel v47r4 for upgrade/current LHCb

Luminosity : Lumi20 ( 2X 1034 cm2s-1 ) , no spillover

Bs ff events

RICH Optics:

• 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.

Several PID combinations: Different Tracking/PID Tuning/RICH Optics. Only a few combinations used in this presentation

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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 trackingimproved compared to that fromCurrent LHCb tracking

RICH1: standard setup

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RICH1 optics“out of focus”

Red: Upgrade LHCb Tracking + Tracks selected with ghost probability cut Cyan: Upgrade LHCb Tracking + All tracks Black: Current LHCb Tracking + Tracks selected with ghost probability cut

RICH1 optics:ROC= 3600 mm

PID from Upgrade LHCb tracking improved compared to that from Current LHCb tracking , for all optics

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Upgrade tracking,ghost probability< 0.3

Red: RICH1 ROC 3800 mmBlack: RICH1 ROC 3800 mm, photon plane shift 100 mmBlue: RICH1 ROC 3600mm , photon plane shift 100 mmCyan : RICH1 ROC 3650 mm, photon plane shift 100 mm

Effect from photonplane shift recovered bychange in ROC

upgrade PID plots wth ‘recent best configuration’

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Current LHCb tracking

Red: RICH1 ROC 3800 mmBlack: RICH1 ROC 3800 mm, photon plane shift 100 mmBlue: 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.

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. (backup slide with full P range).

Blue: Current tuningMagenta: 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 inPID performance in both plots

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Optics and PID tuning : Upgrade LHCb Tracking

Upgrade LHCb Tracking,Current PID Tuning

Upgrade LHCb TrackingOld 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

Red: RICH1 ROC 3800 mmBlack: RICH1 ROC 3800 mm, photon plane shift 100 mmBlue: RICH1 ROC 3600mm , photon plane shift 100 mm

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Optics and PID tuning : Current LHCb Tracking

Current LHCb Tracking,Current PID Tuning

Current LHCb TrackingOld 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 mmBlack: RICH1 ROC 3800 mm, photon plane shift 100 mmBlue: RICH1 ROC 3600mm , photon plane shift 100 mm

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Plans

• Once the exact ROC is decided, freeze the optics geometry for a while.

• Long term: Rebuild the PMT arrays in software, using the Elementary Cells.

• Further tuning of the PID algorithm

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SUMMARY

PID performance verified with different tracking and PID tuning combinations.

The usage of ghost probability gives a minor improvement in PID performance

All the PID performances obtained are consistent with each other and are as expected.

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BACKUP SLIDES

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PID vs Momentum

Upgrade tracking, ghost probability <0.3RICH standard setup (ROC 3800 mm)

Current LHCb tracking, ghost probability <0.3RICH standard setup (ROC 3800 mm)

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PID vs Momentum

Upgrade tracking, All tracksRICH standard setup (ROC 3800 mm)

Upgrade tracking, All tracksRICH standard setup (ROC 3800 mm)Old PID tuning

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Red: Upgrade LHCb Tracking + Tracks selected with ghost probability cut Cyan: Upgrade LHCb Tracking + All tracks Black: Current LHCb Tracking + Tracks selected with ghost probability cut

RICH1 optics“out of focus”

PID from Upgrade LHCb trackingimproved over that fromCurrent LHCb tracking

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Red: Upgrade LHCb Tracking + Tracks selected with ghost probability cut Cyan: Upgrade LHCb Tracking + All tracks Black: Current LHCb Tracking + Tracks selected with ghost probability cut

PID from Upgrade LHCb trackingimproved over that fromCurrent LHCb tracking

RICH1 optics:ROC= 3600 mm

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Red: RICH1 ROC 3800 mmBlack: RICH1 ROC 3800 mm, photon plane shift 100 mmBlue: RICH1 ROC 3600mm , photon plane shift 100 mm

PID has sametrend as in upgrade tracking

Current LHCbtracking

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Red: RICH1 ROC 3800 mmBlack: RICH1 ROC 3800 mm, photon plane shift 100 mmBlue: RICH1 ROC 3600mm , photon plane shift 100 mmCyan : RICH1 ROC 3650 mm, photon plane shift 100 mm

Upgrade tracking,All tracks

Effects from PID tuning

• Some tuning done in 2013• Now re-visiting with current versions• For illustration use tracks with 1.5 < P < 100 GeV/c on this page.

Blue: Current tuningMagenta: Old Tuning

All Plots:RICH1 ROC=3800 mmTop Plot: No shift in photon plane

Bottom plot: Photon plane shift=100 mm

Tuning improved the PID in general,apart from very low momentum tracksbelow 7.5 GeV/c. So a minor retuning forthis in the future.

Black: Current LHCb trackingGreen/Blue: Upgrade LHCb tracking

Blue: Upgrade tracking + RICH2 ‘all small’ PMTsRed: Upgrade tracking + RICH2 mixed PMTs

Red : used as ‘reference plot’ in Dec 2014.

Recapitulation