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MTV - S1183

Beam Time Summary

Performance test of MTV new detector : CDC

Yumi Totsuka

Department of Physics, Rikkyo University, Tokyo, Japan

Schedule: Beam Time 11/3AM – 11/3PM

TRIUMF-ISAC Science Forum (30. Nov. 2011)

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何のテストしたか

CDC (Cylindrical Drift Chamber) MWDC

2009 Run-I

2010 Run-II 2011 Run-III

Motivation

MTV group developed new detector as of this year.

We performed the performance test of it.

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Schedule: Test Run 11/3AM – 11/3 PM

@ ISAC I

OSAKA Beam Line

Beam Time Schedule

Max intensity 10^7 pps

Beam unpol 8Li 28keV

Proton current ~55µA

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MTV experimental principle

MTV…Mott Polarimetry for T-Violation exp.

R≠0

T-Violation

T-transform

: Parent Spin ：Electron Spin

: Electron Momentum

e

e

E

p

J

JR

e

e

E

p

J

JR

J

ep

Zero or Non-Zero ?

Transverse Electron Polarization in Polarized Nuclei

Experimental Sensitivity(~10-4) >> CKM (Standard Model) Predictions (~10-14)

Evidence for the New Physics beyond the Standard Model

Pol. Nuclei

Electron Momentum

Electron Trans. Pol.

R-Correlation Components

Production

Measurement

Measurement

Measurement of Electron Trans. Pol.

Utilizing Analyzing Power of Mott Scattering

measurement of angler distribution of backward

scattered electrons using Mott Scattering is required.

Electron Trans. Pol.

Backward scattering L,R Asymmetry

Beta Decay Rate

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Run-l & ll Setup

J.Onishi 2010 Master thesis

“V-track”

Merits of Tracking Measurement 1. Acceptance

2. Background Rejection

3. Systematic effect rejection due to beta asymmetric emission

Measuring angular distribution of Mott Scattering using Drift Chamber

To see backward scattering left-right asymmetry

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KEK-TRIAC 2008 RNB07K04, RNB08K04

105pps @ 8% pol.

First V-Tracking Measurement almost free from Systematics

sysstat 02404100200R ...

TRIUMF-ISAC 2009 S1183 MTV RUN-I

107pps @ 80% pol.

statR 036.0065.0

Technical issues…

・Exceeding DAQ limit

・Wire Aging

・Space Charge Effect

TRIUMF-ISAC 2010 S1183 MTV RUN-II

Exceed „03PSI(0.2 %), Reaching to FSI(~0.07%) level

107pps @ 80% pol.

New DAQ installation, Wire Repairing, Gas studying completed

Achieved 0.1% statistical precision

Run-ll summary

under preparation for publication

(systematic study) )03'(10)2.29.0( 3 　　　PSI

Be studying Systematic precision

CDC

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CDC Motivation (stat.)

Improving statistical precision

“MWDC”

Lead Foil

MWDC (all 6 sense layer)

Stopping Counter

Beam

Limited solid angle

Next generation detector “CDC”

Lead Foil

CDC (all 4 sense layer)

Beam

solid angle is almost half of 4PI

vertex enlarging

Solid angle!!

6 layer @ 16~20 / layer

All sense wires : 104

4 layer @ 100 / layer

All sense wires : 400

vertex

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CDC Motivation(systematic)

Suppressing systematic error

Polarized nuclei

Can’t get event!!

Effective region P-Violating asymmetry

Polarized nuclei

Analyzer Foil

theta

gamma Gamma asymmetry

Detector geometrical

asymmetry

&

Beam

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CDC design

Wire configuration

Anode (20µm Au-W) ×400

>> signal readout

Shield (100µm Au-Al) ×400

>> shut down noise

Cathode (100µm Au-Al) ×1000

>> applied voltage

Field (100µm Au-Al) ×400

>> applied voltage

half pitch of cell is 4mm

Layer A

Layer B

Layer C

Layer D

design

400mm 700mm

４枚の鉛Foil そのうち2枚が可動式

Mylar Lead foil 100µm

suppress Multiple Scattering!!

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CDC Fabrication

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CDC Fabrication Beam Time

Base development

@ KEK

Completion!!

Wire Set up

Development

@TRIUMF

CDC

First Signal

Mechanical design

Mar.-

frame Fabrication

Chamber design

2010

2011

Jun.- Jul.

Wiring

Aug.

Completion

Sep.

Commissioning R&D

@KEK Oct.

Moving to TRIUMF

Nov.

Commissioning Beam Time

Dec.

Offline test

in June 2011.9.7

in July in August

2009

Run-lll Setup

Lead Foil

Beam

Trigger Plastic Scintillator & Wire hit Lv1 : Plastic Scintillator Lv1.5 : 1hit/layer >> Single Track Lv2 : 2hit/layer >> V-track

Dark Current & Gas

Gas He:CF4=2:1 Minimum current

Layer毎にdifferent the cell size.

So , make HV distribution system.

90Sr Source 10^6Bq

CDC PreAmp out

setup

HV setting & layer hit rate

D: -1750V

Efficiency is much the same!!

A

A:-1650V

A

B B C C

D D

B, C, Cathode, Shield :-1850V

Readout channels : 127ch

Supplying individual voltage

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V-Track event Trigger

Counter

V-track

Single Track event

Trigger

Counter

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ASD output Analog Pulse

(Ar:CF4 mixed)

ASD output Analog Pulse

(He:CF4 mixed)

Ar:CF4=1:1 mixed

10^6 pps @ unpol. Li8

MWDC

TDC [ch] (1000ch = 100ns)

Back-Ground

Co

un

t

TDC [ch] (1000ch = 100ns)

Co

un

t

CDC

He:CF4=2:1 mixed

10^7 pps @ unpol. Li8

Robust baseline stability under high counting rate.

Because of

short drift time,

CDC obtained

high rate capability

TEST BEAM TIME

CO

UN

T about 200ns

Drift Time

TDC Spectrum & Analog out

4µs

600ns

No pile up!!

Beam Intensity 10^7pps

Low Back-Ground Level

Half pitch 10mm

Half pitch 4mm

Worked at 100kHz

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Space Charge Effect

High Beam Intensity, Ions stay around wire.

Reduce electric field around anode wire

Slow drift Velocity, efficiency reduction

Space Charge Effect

CDC Width(charge) distribution

Confirming small

Space Charge Effect

10^5 pps

10^6 pps

10 ^7 pps

Wire pitch 10mm

High rate capability

MWDC Width(charge) distribution

10^5 pps

10^6 pps

10 ^7 pps

Wire pitch 4mm

CDC

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Run-lV….. Placing the trigger counters around CDC

Plastic Board

- ON

- OFF

Plastic Board with/without

Hit Multiplicity / event

distribution Plastic Board

ON/OFF

No accidental effect by Plastic board.

In Run-IV, we decided to put the plastic trigger around CDC!!

Demonstrate for Run-IV

ON OFF

Beam Intensity 10^7 pps

CDC

Plastic scintillator

Plastic board

Run-III

Run-IV

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Vertex position & Mott Scattering angler

distribution Foil IN/OUT

Foil Out

Lead Foil

Beam

Foil In

Declined 2nd event!!

Foil out

Vertex position distribution

Beam

Foil In Foil Out

Beam

Vertex

Position

Confirm good S/N

Foil in

Mott scattering anguler distribution

Beam Intensity 10^7 pps

Mott scattering angle

Foil out

Lead Foil

100µm

Foil in

Beam Intensity 10^7 pps

Double foils

Switched to foils

CDC Current readout

& Future readout

Amp Shaper Discriminator

Sony CXA3183Q

Time Constant : 80nS

CDC

ASD

CAEN V1190A

Readout region

DATA

transfer

Readout Channel : 127ch

Trigger

Counter RUN lll

GND

XILINX XCV150-4PQ240C

TDC

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CDC

ASD All wire readout

DATA

transfer

RUN IV Trigger

Counter

Readout Channel :

800ch FPGA

Merit

SoftwareでDAQ

配線作業がない

周辺回路を組み込める

ATLAS TGC vs BelleⅡCDC

OR

Large DAQ

bandwidth

Bottle neck

CAEN V1495

ASIC FEE

ASIC FEE

FPGA

VME module

Trigger

TDC

Under construction

Trigger

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MTV-G & Run II calibration exp.

𝑷𝑻𝒓𝒂𝒏𝒔𝒗𝒆𝒓𝒔𝒆 𝜽 = 𝛃 ∙ 𝐬𝐢𝐧 𝜽𝒕𝒓𝒂𝒄𝒆 + 𝜽𝑻 + 𝜽𝑮

Coulomb scatt.

Thomas pre.

Geodetic pre.

* Geodetic(de Sitter)precession

We will search short-range gravitational field

around atomic nucleus using MTV detector,

and test the tilting from Longitudinal polarization of

electron spin by analyzing power of Mott scattering. setup & principle

Under preparing now…

MTV-G is Starting from Dec. 1st

時空の歪みに引きずられる、

一般相対性理論の効果による歳差運動

* Thomas precession

誘導磁場と回転座標に伴う歳差運動

Relativistic Precession

By using the electron which have Transverse polarization,

We check whether the principle and the setup

of MTV can performance for the Mott polarimeter.

MTV-G

Calibration exp.

Test of newton gravity at nuclear scale searching for large extra dimension

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Summary

Task for Run lV….

Making a selection ”readout electronics”

Constructing “Trigger System”

* We fabricated CDC and moved from Japan to Canada

* We performed the test experiment with 8Li beam

* V-track was confirmed

* We obtained important data for next run

Beam

Source

Readout Wire

Ch2 Ch1

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Thank you.