Zhangbu Xu (BNL)Ming Shao (USTC)

eSTAR Concept

Kinematics and Acceptance

eSTAR Detector Simulations

Why GTRD

GEM TRD detector R&D progress

Summary

GEM Based TRD R&D Progress

2

Physics Deliverables (EIC whitepaper)

1. Proton Spin2. Motion of partons3. Imagining4. Dense Gluonic

QCD matter5. Quark

Hadronization

3

RHIC: eight key unanswered questionsHot QCD Matter Partonic structure

6: Spin structure of the nucleon7: How to go beyond leading twist and collinear factorization?

8: What are the properties of cold nuclear matter?

1: Properties of the sQGP2: Mechanism of energy loss:

weak or strong coupling?3: Is there a critical point, and if so, where?4: Novel symmetry properties5: Exotic particles

STAR DECADAL PLAN

4

Current STAR Experiment

MRPC ToF Barrel

BBC

PMD

FPD

FMS

EMC BarrelEMC End Cap

DAQ1000

FGT

COMPLETE

Ongoing

MTD

R&DHFT

TPC

FHC

HLT

pp2pp’ pp2pp’

trigger computing

5

STAR Concept

Large Coverage

Low Material

Electron and hadron ID with gas detector and TOF, EMC

Extend this concept to hadron direction GEM tracker (VFGT) Forward Calorimetry

Extend this concept to electron direction Re-instrument inner TPC TRD+TOF Crystal Calorimeter (BSO)

Evolution, not a revolution!

6

DIS – eSTAR Kinematics

Resolution!

Jets

PID

ugprade

x

7STAR Upgrade --- Huan Huang

STAR forward instrumentation upgrade

• Forward instrumentation optimized for p+A and transverse spin physics

– Charged-particle tracking– e/h and γ/π0 discrimination– Baryon/meson separation

eSTAR specific upgrades: EToF: e, π , K identification,ETRD: electron ID and hadron trackingBSO: 5 GeV, 10 GeV electron beamsRe-instrument HFT

FHC (E864)

~ 6 GEM disksTracking: 2.5 < η <

4

RICH/Threshold Baryon/meson

separation?

nucleus electron>2016

W-Powder EMCal

FHC (E864)

Pb-Sc HCal

Forward Calorimeter System (FCS)

BSO

iTPC

ETTIE

8

Proven STAR Capabilities

9

Simulation Geometry

10

A Pythia Simulation Event

Only TPC and ETTIE are

shown

11

Occupancy and pile-up ii)

Beam species

Sqrt(s) Peak Luminosity (cm-2s-1)

Cross section (cm2)

Nch/d Track density (dNch/d MHz)

Hit density impact hit finding

Space charge impact tracking

e+p 5x250 1034 10-28 0.7 0.7

Au+Au 100x100 5x1027 7x10-24 161 6 Minor Corrected to good precision

p+p 100x100 5x1031 3x10-26 2 3 Minor Corrected to good precision

p+p 250x250 1.5x1032 4x10-26 3 18 Significant for inner

Corrected to acceptable

DIS: Q2~>1 GeV2

QED α=1/137 and low multiplicity an order of magnitude lower pile-up than RHIC

12

eSTAR Acceptance

5x250 10x250

GEANT Simulation with eSTAR geometryInclusive Acceptance:Scattered Electron in x-Q2

TPC hits>15BSO and TRD Efficiency assumed 90%

13

x-Q2 coverage (with x resolution <20%)

Energy resolution A Energy resolution A

ep 10+250ep 5+250

iTPC+TRD

pT=2GeV/cWithout iTPCwithout vertex

14

First Stage eRHIC electron/hadron PID

Electron coverage: 1>eta>-2.5PID e/h: 1000

Low material: photon conversion

e

h

INT report (arXiv:1108.1713) Fig.7.18.

15

TPC Inner Sector Upgrade Staggered readout

Only 13 maximum possible points Issues in Tracking: recognition and resolution

Only reads ~20% of possible gas path length Inner sectors essentially not used in dE/dx

Essentially limits TPC effective acceptance to |η|<1

Inner TPC Upgrade:1. MWPC (SDU/SINAP)

ATLAS sTGCChinese 973 project

2. Mechanics (LBL/BNL)Eric Anderson

3. Electronics (BNL/ALICE)4. Schedule (2017)

=±1 =±1.2 =±2

16

TRD+TOF at Endcap (-2<<-1)

Inner tracking TPC (endcap region):

TRD + TOF/Absorber sandwich

• Within <70cm space inside endcap• TOF as start-time for BTOF and MTD

• TOF + dE/dx for electron ID• TOF for hadron PID

• Extend track pathlength with precise points

• High-precision dE/dx (Xe+CO2) TRDMing Shao (USTC)

TPC

IPInner

TrackingIron Endcap

TRD

TOF / Absorber

17

GEM based TRD – R&D Advantage

Few ion feedback to drift volume

High rate Better position resolution Less space charge effect dE/dx Drift along magnetic field

ALICE TRD

Readout: MWPC -> GEM

Multiple time bin readout New type thick GEM

0.2mm

0.5mm

• Prototype TRD with miniDrift GEM (27 time bins)

• Cosmic ray test results• Plan test beam at FermiLab

with other EIC R&D projects in October (T1037)

• Setups at USTC and BNL

18

Pathlength and dE/dx

Gas volume for tracking and dE/dx

dE/dx important for electron and hadron PIDTR is part of dE/dx in tracking

Page 3committee Report

TRD alone

19

dE/dx is crucial in PID

Andronic et al. NIMA 2004

silicon followed by a straw tube/TR system?

To what extent is the TPC tracking sufficient for this as

part of an electron ID system?

20

Students in the Lab

Shuai Yang Sabita Das

21

WTRD and GTRD

Checking the data match of wire chamber and TGEMWire Chamber: STAR TPC readout (107ns per time bin)

GEM: STAR FGT/GMT APV readout (26.7ns per time bin)

22

Sigma of residual (regular GEM: 200μm, Thick GEM(thin gap): 300μm)

(with thin gap) (with thin gap)

Cosmic Ray Tracking(online)

23

GEM based TRD Cosmic Ray Test System

y

z

x

GEM0

GEM1(TGEM)

GEM2

Three GEMs are aligned (Δx=0; Δy=0)23

10.5cm

10.5cm

12.3cm

51.0cm

(0,0,0)

24

Cosmic Ray Tracking(online)

TGEM(thick gap) TGEM(thick gap)

X-axis:strip

Y-axis:pad

TGEM’s HV = 3650V

25

Gain uniformity and stabilityTest at Yale with Fe source

Results with cosmic ray

26

HV Scan and Drift Velocity

Measurements comparisonsALICE Wire TRDResults from journal

2727

Tracklet Reconstruction

TGEM

Search one cluster for each time bin(the APV has 27 time bin; 26.7ns/tb)

Calculate the x(y) of cluster using Center of gravity method for each selected time bin

If the cluster number of one event >=3, fit these points to obtain the slope.

x(y)

v*time bin number

Slope obtained from TGEM

v is the TGEM drift velocity

Meetings discussing the methods

2828

Tracking Slope in x

tgem_slopex1: using the method 1 to obtainslope02_x = (x0 – x2) / (z0 – z2)

The thickness of ionization gap is ~ 1cm, so the resolution of slope

provided by TGEM is consistent with TGEM’s spatial resolution

2929

Tracking Slope in y

30

USTC Test Stand

Copper shield

THGEM

Rail

HV, Shaper

X-ray source

Yi Zhou, Prof. Ming Shao, Cheng Li, Hongfang Chen

31

THGEM foils IHEP

(8 tested)

32

PlansRadiator from ALICE (GSI)Design new gas box (BNL/Yale)Test beam at FermiLab T1037: consortium EIC Tracking and PIDUSTC/IHEP: large foilNew APV readout: IU

The various groups should talk to each other even more.

33

Summary Progress on TRD cosmic ray test results:

Gain uniformity Stability Tracklet with Drift volume for TRD Angular Resolution

eSTAR a possible option for first-stage EIC detector (Electron E<~10 GeV)

Need forward upgrades for eSTAR GEM based TRD a good option for endcap

to extend tracking and PID R&D projects and EIC simulation in progress

34

Tracking with Kalman Filter ii) ~ -1.2

pT = 1GeV/c10 MC tracks

STAR Computing Group: in progress

TRD

TPC

Other upgrades possible improve the tracking resolution: • Inner TPC Upgrade

• Precision Tracker at |r|<50cm

4

720

'2

NLkres

35

iTPC Benefit to electron ID

Improve dE/dx resolution and acceptance

36

Improve electron PID with iTPC

Purity, Efficiency, acceptance

Bingchu Huang

37

Last Committee report 1) Future presentations on this work would benefit from a written text

summarizing the results and referencing the prior reports and milestones. 2) The Committee heard a number of proposals for forward tracking and

PID, some using GEMs in a number of functions. It would be good to understand the extent to which these various efforts are in synergy, are mutually exclusive, utilize overlapping technology, or are in some sort of collaboration already.

3) To what extent is the TPC tracking sufficient for this as part of an electron ID system? Would additional tracking layers, as part of a larger GEM (or other) system, have some advantage? Is there room for such additional layers?

4) What is the optimization of TRD, including the number of measurements, efficiency vs rejection, and use of other tracking layers in the available space?

5) The ATLAS tracking uses silicon followed by a straw tube/TR system. Conceptually there is some relationship to the present proposal. Can you learn anything from the ATLAS experience to help you better understand the usefulness or design of the system proposed here?