# Presentation: 556657

## Trigger Upgrades to the PHENIX Muon Arms

- Mickey Chiu
- University of Illinois at Urbana-Champaign
- for the Forward Upgrade Group

## Quark Flavor Structure Measurement at RHIC

- Parity violating single-spin asymmetries at RHIC provide direct access to the quark flavor structure of the proton spin:

**Polarised PDF**
**Asymmetry Analysis Collaboration ****M. Hirai, S. Kumano and N. Saito, PRD (2004)**

- forward rapidities

## RHICBOS predicted Sensitivity at RHIC

- PHENIX
- central arm: |η|<0.35, ∆=electron
- Muon arm: 1.2<|η|<2.4, ∆=2muon

- GS-A,B

- GRSV valence

## Spin Average Sea Quark Asymmetry

- pQCD implies that u(x)~d(x)
- Non-perturbative processes seem to be needed in generating the sea
- W+/W- measures sea asymmetry

## Requirements for W Analysis

- Ability to Trigger within DAQ Bandwidth
- Assign Track to Right Crossing (timing)
- Reasonable Momentum Resolution / Correct Sign Determination
- How to identify muons from W?

## Why do We need to Upgrade Muon Trigger

-  PHENIX bandwidth: 12KHz (or 24 kHz with additional $2M)
-  W sample is about 104 for the 800pb-1 luminosity. (can’t be pre-scaled!)
-  need additional rejection of 20-50 depending on the beam background trigger rate, i.e. target RF: 104

**Why do We need to Upgrade Muon Trigger**

-  uIDLL1 rejection factor from simulation at sqrt(500)GeV, i.e. perfect shielding is ~**500**
** **uIDLL1 rejection factor from RUN3 p-p data is ~**250** w/o shielding

- Wei Xie

## Backgrounds to the W Measurement

**Charged hadron**

**through absorber**

- Major background from the pion punch through and Z0 decay.
- Measurement: pT>20GeV/c
- Still to Consider:

-  Charged hadron rejection through absorber
-  ~100
- More rejection from the shower profile on the tube.
- More rejection from isolation cut: ~5

**Total rejection: ~10****3**

- Cosmic Background
- Punch Through and Decays
- low p hadrons look like high p

## -

- -

- +

|  | Sagitta<=1 strip | Sagitta<=2 strips | Sagitta<=3 strips |
| --- | --- | --- | --- |
| Rej | 23700 | 10900 | 7180 |

*Result from Kazuya Aoki*

- A birds eye view

**Trigger Option I:  MuTr FEE Upgrade Solution**

- Enough rejection power with good efficiency for high pT muons
- Timing Resolution ~ 100 ns?

## MuTr FEE R&D in KyotoDecember 10, 2004

- Naohito Saito
- Kyoto / RBRC / RIKEN

## Major changes in our strategy

- In the meeting at LANL, splitting signal with transformer is suggested.
- Advantages: Current FEE stays in
- No need of heavy commissioning
- Minimal cost for the installation
- Concerns
- Space
- Transformer in high field???
- Shield with multi-layer shielding metal (suggested by T. Wise)
- Air-core is tried : works, but space??
- How pulse shape would be deformed?
- Decided to work-out transformer option with ASD option as a fall-back position

## MuTr FEE – proposed modification

- MuTr Cathode

- AMU
- ADC

- DCM

## ASD Chip Test Board (ver 1) 

- 8Chips on board
- 4Channels / Chip
- Analog out Gain 0.8mV/fC
- Integration Time
- 80nsec
- LVDS Digital out

## Signal

- 200nsec/div

- Analog out 5mV/div

- Digital out LVDS

## Read Out Schematic

- HV  1900V
- Gas mixture
- Ar:CO2:CF4=50%:30%:20%
- Oscilloscope Termination 10Kohm
- Transformer is handmade : Air-core
- Similar with Ferrite core
- Vmain & Vsub have
-                   the same pulse shape

**Notes:**
Typical charge 300fC
Vmain & Vsub’s Amplitude is different.
The Ratio of Vmain & Vsub is proportional to the sqrt of the ratio of inductances

## Get Digital Signal

- We could get the Digital Output
- Without Distortion of Main Line Signal

## Effect of Noise

- Sub Line Signal is easily affected by Main Line Noise

## Test stand with VDCs in Kyoto

- VDC

- Muon Tracker

- Cosmic Ray

- VDC

-  VDCs to provide space points at MuTr Chamber
-  Position dependence of cathode signal will be studied
-  if successful, position resolution will be studied

## Trigger Option II:  pad chamber solution

******(********)=angle I – angle II: momentum cut**

**Trigger Option II:  pad chamber solution**

## 1 million sqrt(s)=500GeV minimum-bias, full PISA simulation 

| deg | <0.7 | <1.0 | <2.0 |
| --- | --- | --- | --- |
| rejection | 41458 | 22111 | 11845 |

| deg | <0.7 | <1.0 | <2.0 |
| --- | --- | --- | --- |
| rejection | 9851 | 6503 | 3258 |

| deg | <0.7 | <1.0 | <2.0 |
| --- | --- | --- | --- |
| rejection | 31093 | 22011 | 9128 |

- 1 million sqrt(s)=500GeV minimum-bias, full PISA simulation

## Segmentation

- distance between two closet hits as a function of r at 95% probability

- North

- South

- Chun Zhang

- For Trigger, Need ~ 1 phi segmentation, and very little theta segmentation
- Possibility that we might be able to improve pattern recognition in Heavy Ion Collisions simultaneously
- Final Segmentation (8640 channels/plane)
- adds ~ $300K in electronics cost
- Smaller Pads at inner radius
- e.g., for RPC1, inner pad is 2 cm and outermost pad is 9 cm

- 360 () X 24 ()

## Forward Muon Trigger Upgrade Idea

- RPCs (3d space points) for Momentum at Trigger Level

- Instrument MuTr cathodes with trigger electronics (Kyoto)

- W-candidate@(Level-1) = MUID-Road **&** ∆Φ|RPC **&** p>pcut

## $2 Million NSF MRI Proposal

## Current collaborators on W-project

**University of Colorado**
- Frank Ellinghaus, Ed Kinney, Jamie Nagle, Joseph Seele, Matt Wysocki
**University of California at Riverside**
- Ken Barish, Stefan Bathe, Tim Hester, Astrid Morreale, Richard Seto, Alexander Solin
**University of Illinois at Urbana Champaign**
- Mickey Chiu, Matthias Grosse Perdekamp, Hiro Hiejima, Naomi Makins,
- Jen-Chieh Peng, Ralf Seidl, Chris Prokop, John Koster, Aaron Veicht
**Iowa State University**
- John Lajoie, John Hill, Gary Sleege
**Kyoto University**
- Kazuya Aoki, Ken-ichi Imai, Naohito Saito, Kohei Shoji
**Columbia University**
- Cheng Yi Chi, William Zajc
**RBRC**
- Gerry Bunce, Wei Xie
**Abilene Christian University**
- Rusty Towell, Larry Isenhower
**Peking University**
- Yajun Mao, Ran Han, Hongxue Ye, Hongtao Liu

**Current collaborators on W-project**

##    Single Gap RPCs (CMS style design)

-  Gap: 2 mm;
-  HV electrodes : 100 m graphite
-  Gas pressure : ~ 1 Atm
-  Gas mixture: ~ 95% F134a, ~ 4.5% Iso-Butane, 0.5%SF6;
- bakelite resistivity 10 10- 10 12 cm
-   **2-3kHz/cm****2**** in avalanche mode! **

-    Single Gap RPCs (CMS style design)

- Pick-up cathodes and FEE

## Basics of Resistive Plate Chamber: working mode

- The electric field is such that the electron energy  is larger than the ionising potential

-  The separation avalanche-streamer decreases with increasing HV .

-  CMS-RPC will work at _avalanche mode_, to ensure the proper operation at very high rate.

-  RPC has been used in L3, ARGO-YBJ,Belle, BaBar experiments.
-  all 4 LHC experiments will use RPC for muon system.

**From Yong Ban**

## Cost + Schedule

- 2005                                              	First Prototype Test in Run05 Beam
-                                               	Full scale prototype plus electronics
- Winter 2006      			Test of Full scale prototype in Run07
- 2007-2008        			Production of all planes and electronics
- Summer 2007  			Installation in South Muon Arm RPC Trigger
- Winter 2007     			Commissioning of South RPC Trigger in Run08
- Summer 2008  			Installation of North Muon Arm RPC Trigger
- Winter 2008     			Commissioning of North RPC Trigger in Run09
- Run09              			High Luminosity s = 500 GeV p+p Run

## The Structure of Prototype

*PHENIX Forwarding Upgrade Meeting                                                                        Nov. 8, 2004*

**The Structure of Prototype**

- Yajun Mao, Ran Han, PKU

## Top View of A Single Chamber

*PHENIX Forwarding Upgrade Meeting                                                                        Nov. 8, 2004*

**Top View of A Single Chamber**

- Material: 2mm bakelite
-      ( 2~3 × 1011 Ohm.cm ), pressed
-      with melamine foil;
- Size: 43cm×43cm × 0.6cm
- Graphite coat: 40cm × 40cm,
-       resistivity ~130 k/
- 95% R134A, 5% iC4H10
- Gas Flow rate: 1 ml/min
- Gas leakage rate: 2mm/30m
-       drop at 30cm water higher
-       pressure (tested at both with
-       positive and negative pressure)

- spacers

- Yajun Mao, Ran Han, PKU

## A Real View of 2 chambers

*PHENIX Forwarding Upgrade Meeting                                                                        Nov. 8, 2004*

**A Real View of 2 chambers**

- Yajun Mao, Ran Han, PKU

## The Read-Out Strips

*PHENIX Forwarding Upgrade Meeting                                                                        Nov. 8, 2004*

**The Read-Out Strips**

- signal cables

- Yajun Mao, Ran Han, PKU

## Chamber Support/Container

*PHENIX Forwarding Upgrade Meeting                                                                        Nov. 8, 2004*

**Chamber Support/Container**

**Al honeycomb panel, both surfaces are **
**coated with 0.5mm Al foil,  with **
**16mm ****×**** 16mm Al bars**

- Yajun Mao, Ran Han, PKU

## Chamber Support/Container

**Chamber Support/Container**

- Yajun Mao, Ran Han, PKU

## Time Distribution of Background

- Clock
- Forward
- Forward&BBCLL1
- Forward&MUIDS_1D

- Gap from -50 to -10 ns is due to limited size of NTC TDC Window
- Late Hits in BBCLL1 events relative to MUIDS_1D is because the MUIDS_1D comes mostly from muons, while BBCLL1 has lots of hadronic backgrounds
- Evidence for this in ADC Spectrum (in following slides)
- Means Forward&MUIDS_1D selects (probably) muon tracks that go through Muon Arm and hits the forward paddles

- ?

- (for paddle coincidences)

**SC1**

**SC2**

**Shielding**

**Top View**

- Run04 Config

- 12

## RPC Locations

****

**RPC1**

**RPC2**

**SC1**

**SC2**

**Shielding**

**Top View**

**Tunnel View**

## Time Distributions

**RPC1**
**RPC2**
**Scint**

- Time Dist by Channel, Run 171541

- Time Dist by Detector

- Run 171541 and 171548, triggered on RPC1|RPC2|SC1|SC2
- Few noisy channels, on edges of RPC1
- Thresholds raised to get above noise, but will lose efficiency
- RPC1 has separate copper grounds sheets for ease of R&D, get fringe effects
- Much less Incoming Background seen than last year
- Worse for RPC1, in IR, and run dependent
- Location of RPCs further from beam pipe, better beam control?
- RPC and Scintillator Response ~ Same, after accounting for acceptance difference of detectors

**RPC1**

**RPC1**

**Sc**

**40 ns**

**60 ns**

## RPC Scaler Rates

**Scaler rates highly correlated between BBC, MUID, and RPC triggers**
**RPCor doesn’t see any runs with large amounts of background rates**
**Total RPC1&RPC2 Triggers = 1.3e6 events**
**~10****5**** muon tracks per strip, assuming muons trigger RPC1&RPC2**

## Muon RPC Bkg Test

- Response to real background looks like it will be good enough
- But, we would like to see more background!
- In principle, RPCs should be 10X less sensitive to neutrons
- Different Special Conditions to take RPC data
- Polarization Measurement
- Vernier Scan
- Collimation?
- Would like to consult with Angelika to see if measurement of background is interesting to collider physicists.
- Formal request will be put in to PC and RC soon...

- Getting a prototype also allowed us to gain valuable experience with RPC technology...
- The beginnings of our R&D program

## Time Resolution

**Ahn et al, Journal of the Korean Physical Society, Vol 41, No 5, 2002, p 667-673**

**We should be able to get time resolution by looking at Scintillator and RPC coincidences**
**Getting ~1-2 ns resolution**
**Have to fit 2 gaussians in delta-t**

**Sc1-Sc2**

**Sc1-RPC2**

## Efficiency

**CMS gets ~99% efficiency, compared to 90% from Cosmic Ray Studies with RPC Prototype **

- RPC

- Sc1

- Sc2

## Position Resolution

****

**From RPC1&&RPC2 triggers, we should be able to get some muon tracks and determine position resolution (and also efficiency and time resolution)**
**Good Statistics (~100000/strip)**

## Future Tasks

- Decision on NSF MRI Proposal expected in June
- We can press forward with planning until we find out whether we get the money or not
- Many Detector R&D Tasks
- Effects of different gas combinations, humidity, etc...
- Reducing Streamer Rate, reducing noise
- Getting position resolutions to the ~ 0.5 centimeter level
- Double check timing resolution
- Improving efficiency (currently ~ 90% with TOF.W gas)
- Checking aging effects
- Checking rate effects (beam test?)
- Designing and Testing Readout Board and FEMs and Trigger
- Colorado has already started to feel out what is necessary for this
- Want to organize the next wave of R&D
- One RPC to Illinois, one to Colorado at the end of the run.
- Illinois and Colorado to study detector issues,
- Design and build next generation of the prototype (at PKU)
- Full size, resolve current issues, use final materials
- Electronics: Colorado, Nevis, Riverside, IA State
- ACU has students for summer – trigger simulation (with X. Wei)
- GA State has material for another RPC prototype (italian bakelite)

## Possible Way to READOUT RPC (from Chi)

- CMS
- PreAmp
- ASIC

- TDC
- ~(5-10ns or
- Gated )

- Timing Cut

- Large Pad
- Trigger: Road

- 
- Slice trigger

- L1 Data
- Buffer

- DCM

- L1 Trigger

- Possible Way to READOUT RPC (from Chi)

***FPGA***

- RPC
- Cathode

- UCR/Colorado/Nevis

- (IA State)

## Summary

- The W-boson measurement is extremely nice and important
- By far the cleanest measurement of sea quark contribution to spin
- Japanese originally joined PHENIX partly to be able to do this measurement
- The W Boson Trigger has gone through a long twisted path
- Cerenkov Detector, Hodoscopes, Wire Pad Chambers
- Have finally settled on RPC and MuTr FEE Upgrade
- Progress is being made at Kyoto on the MuTr FEE Upgrade, in parallel with RPC
- NSF-MRI submitted for RPC upgrade
- Decision expected this month
- If NSF funds a RHIC upgrade, it’s between HBD, RPC, and STAR FMS
- Final Design not yet Complete for RPC
- This is the time to let us know of any input you might have for the design
- Improvements in Pattern Recognition
- More Sophisticated Triggering
- Upsilon in Au+Au?
- R&D Progressing Nicely

## Backup Slides

## Inclusive charge hadron spectrum (PYTHIA and UA1) 

## Beam test results of  Chinese RPC prototype

- Conclusion:
**The Chinese RPC prototype has good mechanical strength,gas-tightness and HV performances;**
**The efficiency and time resolution are satisfactory;**
**The efficiency at very high irradiation is limited due to the high resistivity of the bakelite.**
** **The PKU-RPC group accumulated experience and technical know-how of RPC.

**From Yong Ban**

## Background Study in Run04 p+p Using Paddles *

- Background Study in Run04 p+p Using Paddles *

- 1

- Bkg
- Scint.
- (9”x12”)

- 33”

- 23.5”

- MuID Hole

- Beam
- Pipe

- 2

- Beam View

- Side View, South Arm

- fan in/fan out

- 62ns Delay

- NTC
- FEM

- 10 cm

- 31 ns

- * Commissioned by Xie Wei and Hiro Heijima

- Paddle Locations

## Scaled RPC Trigger Counts

**Total Scaled Counts so far:**
**bbc    1.0111e+09 muid   9.65415e+07 rpcand 1.31369e+06 rpcor  432802**

##    PHENIX forward upgrade

| deg | <0.7 | <1.0 | <2.0 |
| --- | --- | --- | --- |
| rejection | 36000 | 19980 | 10090 |

- Achieved enough trigger rejection

- increase of pion rejection via isolation cut
-  possible background rejection via reconstructing W transverse mass.
-  possible improve of momentum resolution with well defined determined vertex.

*RPC LL1 trigger (NSF proposal)*

*MuTr LL1 trigger (Funding in Japan)*

- μ

## Simulation Efforts

- Matthias Grosse Perdekamp, RBRC and UIUC

**Nosecone calorimeter trigger: **
*	**Kelly Corriea: *Topology based trigger
**Cerenkov trigger:**
**	***Jennifer Hom*:     cerenkov detector + uIDLL1
**Lookup table Trigger:**
**	***Hal Haggard*:      scintillator hodoscope solutions
-             *Greg Ver Steeg*:   hodoscope solution*muID
**Tracking trigger:****                                         **
*	**Kazuya Aoki *and*  Wei Xie:   *Various tracking solution matching muID roads, studies from data
**Beam Related Background:**
-             *Vasily Dzhordzhadze:*    Mars based beam background simulations (ongoing)
**(details see: http://www.phenix.bnl.gov/WWW/trigger/muonupgrade)**
**                                         **

** **

##  R&D and test data

-  R&D and test data

- Matthias Grosse Perdekamp, RBRC and UIUC

**Evaluation of muID LL1**
**                             ****Wei Xie, Ken Barish: using run 03 data  (UCR)**
**Background**
**                             ****Hiroki Sato: run 02      (Kyoto)**
**                             ****Ken Read, Vasily Dzhordzahdze, Vince Cianciolo: run 03, ****run04 (UT, ORNL)**
**                                         ****Wei Xie, Hiro Hiejima, MGP (RBRC, UIUC)**
** **
**Cherenkov**
-                              **Kazuya Aoki, Naohito Saito, Atsushi Taketani: run 03 (Kyoto, RIKEN)**
**Nosecone**
**                             ****Mikhail Merkin, Edward Kistenev, Richard Seto**, Gianluigi Sampa
**                                         ****(MSU, BNL, UCR, INFN Trieste)**
**MuTr           **
**                                         ****Kazuya Aoki, Hiroki Sato, Naohito Saito, Doug Fields (Kyoto, UNM)**
**RLT/RPC             ****Hiro Hiejima, Alex Linden Levy, Cody McCain, Jen-Chieh Peng,**
**                                        ****Joshua Rubin, Wei Xie, Matthias Grosse Perdekamp (UIUC, RBRC)**

** **

##                  R1  Real Estate

-                  R1  Real Estate

##        Beam Background simulations

- Blue beam

- Yellow beam

- MuID

- MuID

-        Beam Background simulations

**Vasily Dzhordzhadze**

## Particles

**Particles**
** ****reached MuID**
** ****Gap 5 absorber**

- 10K 100 GeV protons
- incident on Q03
- Integrated overall
- Energies