Performance of PHENIX High Momentum Muon Trigger

1

2 34

5

678

Muon Tracker

Octant number

4

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

5

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

Threshold ScanRun # Threshold S.SG1 N.SG1

383156 10mV 11kHz 750Hz

383160 20mV 76kHz 18kHz

383159 20mV 20kHz 8kHz

383161 30mV 15kHz 32Hz

383162 40mV 200Hz 1Hz

383163 40mV 20kHz 1Hz

383164 40mV 2kHz 1Hz

383165 60mV 1.7kHz 0.5Hz

383168 100mV 14Hz 0.4Hz

383170 60mV 3.8kHz 1.0Hz

• Good correlation between threshold and N.SG1. 1Hz is reasonable true cosmic rate.• Poor correlation between threshold and S.SG1. Not rates are not reproducible.

6

North Threshold Scan

All Octants (Thr=40mV)

Measurement and study by SeYoung and Dahee

SG１

Sout

h Tr

igge

r Rat

e

Expected trigger rate for cosmic ~1Hz]

Masking Octant-1 (Thr=40mV)

Study by Dahee and SeYoung

20min

Oct

-1 E

ffect

Observation So Far

1. Octant-1 which has intrinsic eigenvalue of 300Hz@40mV.– This high rate quenches completely by masking

octant-1. Masking at LL1 or MRG doesn't matter.

2. Rate excursion up to >10kHz with 5 -10 minutes of lifetime originated Octant-3. Excursion repeats during the run.

MRG LL1 GL1

Oct-3Excursion

yesADTX

Oct-1HighRate

yes

MRG LL1 GL1 noADTX no

✖mask

MRG LL1 GL1 noADTX✖

mask

Logic Test

yesno

yesno

MRG LL1 GL1 noADTX✖

High Threshold

yesno

no10-13min

no nonono

yesyesyes

~60min

no

SG1 Chain

FPGA

MRGADTX LL1

DCMIF DCM

MTPcasset

MTP fiber

12

3

456

7

89

10

FPGAMaskThreshold

13

Threshold Scan

Threshold change every stations all together.

Threshold [mV]

SG1_

Sout

h Ra

te [H

z]

• The threshold scan result indicates clear threshold dependence. • The slope somewhat gets shallow between 30mV to 60mV. • Compared to North, South rate responses quite shallow and not normal response.

Plot by Dahee

Threshold change only station-3aMRG#80 (rests are fixed at 40mV).

North

14

Difference between Previous and Current MRG FPGA code

Previous (mrg_prom021.xsvf)

Current (mrg_prom036.xsvf)

Process Speed~ 10ns faster

Minimize Dt between stations

Dt (St3 – St1) ~ 20nsDt (St2 – St1) ~ 8ns

Beam Clock Counter Employ Counter from ADTX

Employ Counter within MRG

Error DetectionNo Error Detection of

ADTX channel by channel

Error Detection of ADTX channel by channel

15Upgrade : March 28, 2012Run12: March 18 ~ April 18, 2012

SG1 Octant-3 High Rate ExcursionPlot by SeYoung (Ewha University)

Frequency stays reasonably constant, whereas amplitudes vary by factor of 6 or so.

20kHz

16

Peak to Peak Intervals

Intervals are constant within +/- 30 seconds. However their variations can notbe explained within the peak position error.

Plot by Dahee

Run13 Threshold Response of Octant-1

North

South

Run12 Octant-1 Cosmic SG1~50kHz

Run12 Octant-1 Physcs SG1~1kHz

Plot by Dahee (Ewha University)

18Run12 Cosmic Rate ~40kHz is consistent with present measurement.Physics run was operated at 30mV and likely to be operated around 1kHz.

PHYSICS INTRODUCTION AND MUON TRIGGER SYSTEM

sqrt(s)=500 GeV @ RHIC

Parity Violation AsymmetryClean flavor separationw/o fragmentation uncertainty

21

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

22

New MuTRIG-FEE in North Arm

Before Install

2008 Install

Diagnosis

23

Threshold scan.✔Angular distribution of cosmic✔

Antimask all octants✔

Fiber swap btwn MRG&LL1

For more information

• S. Adachi, et. al., Nuclear Inst. and Methods in Physics Research, A (2013), pp. 114-132