Muon Detection for DDVCS in Hall A - ectstar.eu · Muon Detection for DDVCS in Hall A ... 4 m² of Micromegas detectors to be installed in 2015/2016 ... µ-RWELLis a new promising

Muon Detection for DDVCS in Hall A

Kondo Gnanvo

University of Virginia, Charlottesville, VA

ECT Trento Dileptons Workshop, October 25, 2016

ECT Trento Dileptons Workshop 210/25/2016

DDVCS in Hall A @ JLabIro

n p

lates

SoLID JPsi Setup

Target moved • 2m from Jpsi position inside

Iron plate from • 3rd layer yoke in front and behind

calorimeter & Remove Gas Cerenkov

10 • uA on 45 cm target, Try to reach 1038 cm-2s-1

Dedicated setup

g* + p g‘(*) + p’

m+ + m-

Guidal and Vanderhaegen : Double •

deeply virtual Compton scattering off the nucleon (arXiv:hep-ph/0208275v1 30 Aug 2002)Belitsky Radyushkin : Unraveling •

hadron structure with generalized parton distributions (arXiv:hep-ph/0504030v3 27 Jun 2005)

Adding forward and large angle muon detectors


Large area detector for a complete coverage of the muon detection

High rate capabilities and good position resolution

Low cost detector technology

Micro Pattern Gaseous Detectors are obvious candidate for the muon detection

Basics requirements for Muon Detection

Micro Pattern Gaseous Detectors (MPGDs)


GEM: Gas Electron Multipliers

F. Sauli, Nucl. Instr. and Meth. A386 (1997) 531

Micromegas: MICRO MEsh GAseous Structure

Y. Giomataris, Nucl.Instr. and Meth. A419 (1998) 239

Some performances of MPGDs

Recent breakthrough in MPGDs


Single mask technique for GEM foil production: Large area GEMsResistive Micromegas

Standard Micromegas resistive Micromegas

GEMs for the Super Bigbite Spectrometer (SBS) @ JLab Hall A


s = 65 mm

ResolutionGain efficiency

SBS Back Tracker layer

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Proton arm in the Gep(5) configuration

60 cm

SBS GEMs can be used later for Hall A DDVCS Muon detectors


ATLAS Muon Upgrade: Micromegas Small Wheel (MMSW)

prototype chamber

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Price to pay in term of rate capabilities

Breakthrough with Resistive Micromegas

Micromegas Small Wheel (MMSW)


Micromegas Vertex Tracker (MVT) for CLAS12 in Hall B

Micromegas Vertex Tracker :

Improve the track reconstruction in the vicinity of the

target in 5T field

Limited space bet. the magnet and the Silicon Vertex

Tracker (SVT)

Large curved resistive Micromegas, small dead space

4 m² of Micromegas detectors to be installed in 2015/2016

DREAM Front -End Electronics

M. Vandenbroucke, MPGD2105, Trieste 10/2015

Efficiency map

Forward MVT Tracker

Barrel MVT Tracker

New MPGD technology: Micro Resistive Well detector (µ-RWell)

The µ-RWELL_PCB is realized by coupling:

1. a “suitable WELL patterned kapton foil as “amplification stage”

2. a “resistive stage” for the discharge suppression & current evacuation:

“Low particle rate” (LR) << 100 kHz/cm2: single resistive layer

surface resistivity ~100 M/

“High particle rate” (HR) >> 100 kHz/cm2: more sophisticated

resistive scheme must be implemented

a standard readout PCB3.

Drift/cathode PCB

Copper top layer (5µm)

DLC layer (0.1-0.2 µm)

R ̴50 -100 MΩ/□ Rigid PCB readout electrode

Well pitch: 140 µmWell diameter: 70-50 µmKapton thickness: 50 µm

1

2

3

µ-RWELL PCB

G. Bencivenni et al., 2015_JINST_10_P02008

The µ-RWELL detector is composed by two elements: the cathode and the µ-RWELL_PCB .

G. Bencivenni, RD51 Coll. meeting, Aveiro, 09/2016


It combines the advantages of both GEMs & Micromegas

Like Micromegas ➩ single amplification stage, thin structure,

low material budget

Like GEM ➩ Simple structure ⇨ just like GEM foil combine

with the readout strips / pads, flexible geometry

Unlike GEM and Micromegas, ⇨ no stretching needed,

support could be flexible or rigid PCB board

Possibility to add a pre -amplification GEM foil if needed

Low cost MPGD detector

Performances of µ-RWell detectors

Gain: ✔ is one order of magnitude higher

gain than a single GEM at the same

bias voltage

Spark rate: ✔ Very low spark rate and

current at high gain

✔ Robust and simple detector

G. Bencivenni et al, JINST 10 P02008, 2015; doi:10.1088/1748-0221/10/02/P02008


Performances of µ-RWell detectors

G. Bencivenni et al, JINST 10 P02008, 2015; doi:10.1088/1748-0221/10/02/P02008

The current limitation of this technology is its rate capability compared to GEM detectors

Same issue as for Resistive Micromegas

Study of electrical properties of resistive materials that allow high rate and quenched discharge

But gain stability demonstrated for rate up to 100 kHz/cm2



mini-drift m-RWELL detector

Muons hitting the chambers at vary large incident angle

Using m-RWELL in mini drift mode ⇨ Excellent tracking

capability with one detector layer at very low overall cost

Large drift gap

Curved mini drift m-RWELL

CLEO magnet


R&D on mini-drift MPGDs

Benefit from existing and extensive R&D work done with Micromegas and GEM detector as mini drift detector

M. Iodice et al, JINST 10 C02026, 2015; doi:10.1088/1748-0221/10/02/C02026

Micromegas mini-drift

B. Azmoun et al, http://arxiv.org/abs/1510.01747

GEM mini-drift


mini-drift m-RWELL: zigzag readout strips

Drift region for r coordinate

Drift region for φ coordinate

zigzag strips readout ⇨ limited electronics channels

A. Zhang et al. NIM A 811 (2016) 30-41

2D (r,φ) coordinate detector ⇨ built from 2 x 1D m-RWELL amplification device


New Structures: Chromium GEM (Cr-GEMs)

Standard GEM

5 mm Cu

50 mm

Kapton

100 nm Cr

50 mm Kapton

Cr-GEM

100 nm CrCharacteristics of Cr-GEM foil:

Copper (Cu) clad raw material comes with 100 nm

Chromium (Cr) layer between Cu and Kapton, 5mm Cu

layers removed, leave only 100 nm residual Cr layers as

electrodes, Cr-GEM foils provided CERN PCB workshop

This is particularly interesting for the Nuclear Physics

community where will be used GEMs are used as tracker in a

high background of low energy photon.

Using Cr-GEM foil lead to almost 50% reduction of the

material of an EIC light weight triple-GEM detector: this is

because the material in a lightweight triple-GEM is

dominated by GEM foils,


New Structures: Chromium GEM (Cr-GEMs)

Using Cr-GEM foil lead to 50% reduction of the material compared to standard light-weight triple-GEM detector: this is

because the material in a light-weight triple-GEM is dominated by GEM foils,


Higher luminosity ?• Current could go up to 80 uA• Target length up to 1 meter• Tracker occupancy and photon background

– Reduce amount of Copper in GEM (or remove Copper ⇨ Chromium GEM Cr-GEM)– Micromegas option (or m-RWELL)– Build smaller chambers and add more channels– Study complement with 2D pad readout – Superconducting tracker option

• Calorimetry– Study liquid scintillator and cryogenics calorimeter option– Superconducting detector to replace PMT ( 1 ns width pulse to increase rate capability )

• Cerenkov– Superconducting detector to replace PMT ( 1 ns width pulse to increase rate capability )– HBD type Cerenkov for Large Angle calorimeter

6. 10^38 cm-2s-1

Technically doable mostly matter of costA. Camsonne, INPC2016 Adelaide, Australia 2016

ECT Trento Dileptons Workshop

Conclusion

Micromegas and GEM detectors are proven technologies for tracking particle and

muon detection in Nuclear Physics

µ-RWELL is a new promising MPGD structure for muon detection at high

performance and low cost in a high rate environment such as the DDVCS

opportunities of the 12 GeV era @ JLab

Detector R&D is needed to prepare for an ever increased luminosity to improved the

statistical accuracy for DDVCS dedicated setup in Hall A

1810/25/2016

Documents

Muon Detection for DDVCS in Hall A - ectstar.eu · Muon Detection for DDVCS in Hall A ... 4 m² of Micromegas detectors to be installed in 2015/2016 ... µ-RWELLis a new promising