Performance of PHENIX High Momentum Muon Trigger

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sqrt(s)=500 GeV @ RHIC

Parity Violation AsymmetryClean flavor separationw/o fragmentation uncertainty

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PHENIX Detector

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New MuTRIG-FEE in North Arm

Before Install

2008 Install

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High Momentum Muon TriggerRun11 500 GeV Projection

New TriggerUpgrade

MuIDTrigger

Rate

9 MHz

90 kHz

σtot=60mb

L=1.5x1032cm-2s-1

BBCMuID Rejection PowerRP~100

Trigger UpgradeRP ~ 45

2 kHzPHENIX Band Width for Muon

Required Rejection Power

RPtot ~ 4500

1. High Rejection Power2. High Efficiency

W

陽子陽子

衝突により陽子が粉砕された現象を観測 8

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1

2 34

5

678

Muon Tracker

Octant number10

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MuTR FEE Upgrade Readout Analog Signal to Get the Position of Particle Passage (OFFLINE Analysis)

Get Digital Signal for Trigger Decision (ONLINE)

Readout Analog Signal to Get the Position of Particle Passage (OFFLINE Analysis)

To triggerLogic

ADC

0.95Q

0.05Q

Q

1. Charge Sharing with multilple strips provides ~200um resolution out of 5mm strips

2. Fast readout electronics process signal fast enough before trigger decision is madeBottom Line

~10s

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High Momentum Muon Trigger System

MuTRGADTX

MuTRGMRG

Level 1TriggerBoard

MuTrFEE

Resistive Plate Counter(RPC) (Φ segmented)

B

2 planes

5%

95%

Trigger

Trigger

Trigger

Interaction Region Rack Room

Optical

1.2Gbps

Amp/Discri.Transmit

DataMerge

MuTRG

RPCFEE

Trigger events with straight track(e.g. Dstrip <= 1)

RPC / MuTRG data arealso recorded on disk.

SG1

DCM

BBC

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• 2 central arms: electrons, photons, hadrons– charmonium J/, ’ -> e+e-

– vector meson , , r w -> e+e- – high pT po, p+, p-

– direct photons– open charm – hadron physics

• 2 muon arms: – “onium” J/, ’, -> m+m- – open heavy flavor– W -> m (500GeV)

Excellent trigger and DAQcapabilities: multiple trigger

signature important for spin physics can be taken in parallel with high

bandwidth!

PHENIX Detector

Beam-Beam Counter (BBC)

NorthSouth

144.35 cm

⊿η = 3.1 ~ 4.0

⊿φ = 2π

Purpose of PHENIX BBC

Collision Vertex initial point of charged particle tracking

Minimum Bias Trigger Level1 Trigger with Online

Vertex Cut

Time-Zero Determination Start Timing for

ToF Measurements

Reaction Plane DeterminationDirection of Impact

Parameter

Centrality Determination

Impact Parameter Determination with ZDC

Each element is assembled byQuartz Cherenkov radiator(bth=.7)and meshed dynode PMT.

BBLL1Selected(ZDC&BBLL1)

ZDC triggered

Z-Vertex and Time zero

TN/S : average hit time, c : light velocity, L : 144.35 cm

• Z-Vertex

• Time zero

BBC North

BBC South LL

Vertex position TNTS

Rejection Power

• Rejection Power = BBC(no vertex) / SG1 trigger

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MUON_S_SG1&BBCLL1(noVtx)MUON_N_SG1&BBCLL1(noVtx)MUON_S_SG1_RPC3_1_B||CMUON_N_SG1_RPC3_1_B||CMUON_S_SG1_RPC3A&MUID_S1DMUON_N_SG1_RPC3A&MUID_N1D

BBCLL1(>0 tubes) novertex

BBC: Beam-Beam Counter

Run Database

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Getting BBC Rate

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1.7MHz

Rejection Power vs. BBC Rate

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