L0 trigger update

Bruno AngelucciINFN & University of

Pisa

NA62 Physics & TDAQ WG – CERN 04/06/14

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Outline

•“Feasible for first 2014 run” L0 trigger▫Detectors involved▫Signal handling▫Primitive generation

•L0 rates and efficiencies▫Study of crucial subdetectors parameters▫Rejecting power of vetoes

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Introduction•Software used▫NA62MC and NA62Reconstruction rev301 100k πνν events + 100k of 6 K main decays + 4 muon

halo components + beam pions no accidentals

▫NA62MC and NA62Reconstruction rev314 10k πνν events + 10k of 6 K main decays accidentals superimposed to central event at

generation level (±150 ns)• L0 trigger Analyzer developed under NA62Analysis

FW

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Detectors• RICH primitive

▫ Multiplicity counting hits in time bins Low and High multiplicity

• CHOD primitive▫ Coincidence in space (correspondent quadrants)▫ Coincidence in time▫ Multiplicity grouping coincidences in time bins

Max hit multiplicity Quad multiplicity

• MUV3 primitive▫ Time coincidence of 2 PMs of same pad

• LKr primitive▫ Combining cells in SuperCells (SC) in same time bin▫ Combining SCs in clusters: same time bin, adjacent▫ Thresholds both for cell and SC energy▫ 2 or more clusters in time

• LAV12 primitive▫ Hits with low and high threshold channels firing▫ Slewing timing correction▫ Offset of different layers

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CHOD Primitive multiplicity

All πνν decays

Signal (πνν passing conditions)

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LKr L0 efficiencies

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Signal selection

•Kinematic requests▫15 <Pπ< 35 (GeV/c)▫105 < Zvtx < 165 (m)▫0 <M2

miss < 0.01 || 0.026 <M2miss < 0.068 (GeV2/c4)

•Acceptance requests▫No pion decay before LKr▫Pion in CHOD and MUV3 acceptance▫Pion not in LAVs acceptance

•Resulting πνν acceptance: order of 10%

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L0 Parameters• The goal is to check efficiencies and rates varying one

parameter at a time keeping fixed all others•RICH▫Time bin▫Low multiplicity threshold▫High multiplicity threshold

•CHOD▫Time bin▫“Max” multiplicity threshold▫Quadrant multiplicity threshold

• LKr▫Cell energy threshold▫SuperCell energy threshold▫Time bin for cell time▫Δt for SC and cluster matching

• L0TP primitive matching time

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No accidentals

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With accidentals

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With accidentals

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With accidentals

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No accidentals

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With accidentals

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L0 Parameters•RICH▫Time bin = 3.125 ns▫Low multiplicity threshold = 4▫High multiplicity threshold = 28

•CHOD▫Time bin = 1.5625 ns▫“Max” multiplicity threshold = 10▫Quadrant multiplicity threshold = 2

• LKr▫Cell energy threshold = 0.1 GeV▫SuperCell energy threshold = 0.7 GeV▫Time bin for cell time = 12.5 ns▫Δt for SC and cluster matching = ±6.25 ns

• L0TP primitive matching time = ±(1.5625,3.125) ns

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Rejection powerWith accidentals

0: RICH & CHOD & !MUV3 & !LKr & !LAV1: RICH & CHOD & !LKr & !LAV

2: RICH & CHOD & !MUV3 & !LAV3: RICH & CHOD & !MUV3 & !LKr

No accidentals

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Final results

•No accidentals▫Efficiency: 91.1±0.3 %▫Total rate: 360±11 kHz

•With accidentals (halo missing)▫Efficiency: 76.7±1.3 %▫Total rate: 425±15 kHz

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Spares

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With accidentals

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With accidentals

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With accidentals

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With accidentals

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With accidentals

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With accidentals

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With accidentals