E21 COMET Reportnuclpart.kek.jp/pac/1201/pdf/J-PARCPAC120114_kuno_short.pdfYoshitaka Kuno Osaka...

E21 COMET ReportYoshitaka Kuno

Osaka Universityon behalf of the COMET collaboration

January 14th, 2012

1

Progress Reportof

Experimental Search for Lepton Flavor Violating µ! ! e!

Conversion at Sensitivity of 10!16

with a Slow-Extracted Bunched Proton Beam(COMET)

J-PARC E21

Jan 13, 2011

Abstract

We describe the progress made since the last PAC presentation in realising theCOMET experiment that is seeking to measure neutrinoless muon to electron con-versions with a sensitivity of 10!16 using a slow-extracted bunched proton beam atJ-PARC.

1

Resources shared between COMET and Mu2eProgress Report for COMET

The progress report of January, 2012 has been distributed to the J-PARC PAC.

2

Resources shared between COMET and Mu2eOutline

• What is COMET (J-PARC E21)?• COMET TDR status• Highlights of COMET R&D

• Solenoid Magnet Design• Detector R&D• Others• COMET_g4

• COMET Collaboration• Response to MTF/JPNC proposal (staging approach)• Summary

3

Resources shared between COMET and Mu2eWhat is COMET?

8GeV proton beam5T pion capture solenoid

3T muon transport(curved solenoids)

muon stoppingtarget

electron tracker and calorimeter

electron transport

B(µ� + Al⇥ e� + Al) = 3.3� 10�17

B(µ� + Al⇥ e� + Al) < 7� 10�17 (90%C.L.)

2.6

6

Experimental Goal of COMETJ-PARC E21

• 1011 muon stops/sec for 56 kW proton beam power.

• C-shape muon beam line and C-shape electron transport followed by electron detection system.

• Stage-1 approved from the J-PARC PAC in 2009.

10,000 improvement over the previous

4

COMET Technical Design Report (TDR)

5

Technical Design Reportfor




J-PARC E21

January 13, 2012

Contents

1 Introduction 10

2 Physics Motivation 122.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2.1.1 History I — the establishment of the concept of lepton flavor . . . . 122.1.2 History II — the discovery of lepton flavor violation in neutrinos . . 13

2.2 New physics and µ!!e! conversion . . . . . . . . . . . . . . . . . . . . . . 142.3 Supersymmetric models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.3.1 General feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152.3.2 Models with the seesaw mechanism . . . . . . . . . . . . . . . . . . . 16

2.4 Little Higgs models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172.5 Extra dimensional models . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.5.1 Anarchic Randall-Sundrum model . . . . . . . . . . . . . . . . . . . 192.5.2 UED models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.6 µ!!e! conversion at LHC era . . . . . . . . . . . . . . . . . . . . . . . . . 212.7 Phenomenology of µ!!e! conversion . . . . . . . . . . . . . . . . . . . . . . 22

2.7.1 What is a µ!!e! conversion process ? . . . . . . . . . . . . . . . . . 222.7.2 Signal and background events . . . . . . . . . . . . . . . . . . . . . . 222.7.3 µ!!e! conversion vs. µ+ " e+! . . . . . . . . . . . . . . . . . . . 23

2.8 Present experimental status . . . . . . . . . . . . . . . . . . . . . . . . . . . 232.8.1 µ!!e! conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.8.1.1 SINDRUM-II . . . . . . . . . . . . . . . . . . . . . . . . . . 242.8.1.2 MECO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252.8.1.3 Mu2e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.8.2 µ+ " e+! Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272.8.3 Why is µ!!e! conversion the next step ? . . . . . . . . . . . . . . . 27

3 Overview of COMET 293.1 Introduction to the COMET experiment . . . . . . . . . . . . . . . . . . . . 293.2 Advantages of the COMET experiment . . . . . . . . . . . . . . . . . . . . 31

4 Proton Beam 324.1 Requirement for proton beam . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4.1.1 Proton energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324.1.2 Proton beam power . . . . . . . . . . . . . . . . . . . . . . . . . . . 334.1.3 Proton beam time structure . . . . . . . . . . . . . . . . . . . . . . . 33

4.2 Acceleration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

4


COMET Technical Design Report (TDR) has been almost complete. It has already about 200 pages. Some highlights in TDR have been included in the progress report.

6

Technical Design Reportfor




J-PARC E21

January 13, 2012

Contents

1 Introduction 10

2 Physics Motivation 122.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

2.1.1 History I — the establishment of the concept of lepton flavor . . . . 122.1.2 History II — the discovery of lepton flavor violation in neutrinos . . 13

2.2 New physics and µ!!e! conversion . . . . . . . . . . . . . . . . . . . . . . 142.3 Supersymmetric models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.3.1 General feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152.3.2 Models with the seesaw mechanism . . . . . . . . . . . . . . . . . . . 16

2.4 Little Higgs models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172.5 Extra dimensional models . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.5.1 Anarchic Randall-Sundrum model . . . . . . . . . . . . . . . . . . . 192.5.2 UED models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.6 µ!!e! conversion at LHC era . . . . . . . . . . . . . . . . . . . . . . . . . 212.7 Phenomenology of µ!!e! conversion . . . . . . . . . . . . . . . . . . . . . . 22

2.7.1 What is a µ!!e! conversion process ? . . . . . . . . . . . . . . . . . 222.7.2 Signal and background events . . . . . . . . . . . . . . . . . . . . . . 222.7.3 µ!!e! conversion vs. µ+ " e+! . . . . . . . . . . . . . . . . . . . 23

2.8 Present experimental status . . . . . . . . . . . . . . . . . . . . . . . . . . . 232.8.1 µ!!e! conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.8.1.1 SINDRUM-II . . . . . . . . . . . . . . . . . . . . . . . . . . 242.8.1.2 MECO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252.8.1.3 Mu2e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.8.2 µ+ " e+! Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272.8.3 Why is µ!!e! conversion the next step ? . . . . . . . . . . . . . . . 27

3 Overview of COMET 293.1 Introduction to the COMET experiment . . . . . . . . . . . . . . . . . . . . 293.2 Advantages of the COMET experiment . . . . . . . . . . . . . . . . . . . . 31

4 Proton Beam 324.1 Requirement for proton beam . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4.1.1 Proton energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324.1.2 Proton beam power . . . . . . . . . . . . . . . . . . . . . . . . . . . 334.1.3 Proton beam time structure . . . . . . . . . . . . . . . . . . . . . . . 33

4.2 Acceleration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

4


COMET Technical Design Report (TDR) has been almost complete. It has already about 200 pages. Some highlights in TDR have been included in the progress report.

Submit by the March J-PARC PAC

6

Highlights of COMET R&D

7

Superconducing Solenoid Magnets

8

DD KN31460-a

4 96 設計要項表 Design Data Sheet

全体形状

DD KN31460-a


磁場プロファイル磁場プロファイルの現段階での計算値を図２にまたその計算の元となるコイルパラメーターを表１に

示す。計算は空芯で行っているが実際のコイルは全て鉄ヨークの中に内包される鉄ヨーク付きでの磁場設計も設計検討の範囲とする。また図２の磁場はまだ完全には最適化されていない。磁場の設計仕様はパイオン捕獲磁石の中心部で 5T以上の磁場を最大値として、ミューオン輸送ソレノイドでは３T、スペクトロメーターから検出器では 1T の磁場とする。パイオン捕獲磁石は、標的中心より 100mm上流に磁場ピークを持つこと。図２では空芯計算のためターゲット中心（z=0）で磁場ピークを持つが、鉄ヨークをかぶせることでピーク位置を z=-100mmとする。ソレノイド磁場分布は、パイオン捕獲磁石の中心からスペクトロメーター(SS)にかけて単調減少で落

ちていく必要がある。このとき単調減少が要求されるのは、ダイポール磁場を持つ TS2,TS4,SSを除いた領域で、ソレノイド中心から半径 150mmの範囲を目標とする。（150mmの目標範囲が非常に困難な場合は別途協議の上、目標範囲を変更する可能性もある。）図 3 に示すように捕獲ソレノイド内部には放射線シールドを設置する。このシールド内側の陽子標的より下流側の領域で要求された磁場分布を満たすよう、捕獲ソレノイドコイルおよびマッチングソレノイドコイルを分割する等、形状、配置を最適化すること。 ST1～ST3 のボア内には、ミューオン停止標的として多数のアルミ薄板（直径 200mm）を軸方向 800mmに渡って並べる。ミューオン停止標的の一番上流側で 2.4テスラ以上、最下流側で 1.90テスラ以下となるよう磁場勾配を持つこと。

図１.２．1 COMET Solenoid System 概要

Resources shared between COMET and Mu2eCOMET Magnet System

1) Pion capture solenoid (CS)2) Matching solenoid (MS)3) Muon transport solenoid (TS)4) Muon stopping target solenoid (ST)5) Spectrometer solenoid (SS)6) Detector Solenoid (DS)7) Correction dipole coils for TS and SS

9

DD KN31460-a


全体形状

Resources shared between COMET and Mu2eCOMET Solenoid Magnet Study includes

• magnetic field distribution with iron yoke

• electromagnetic forces with iron yoke

• coil design • cryogenic system• mechanical analysis of

cryostats and coil supports• cryostat design• quench protection system• influence of radiation on

superconductors Return yoke

� Iron yoke covers from end to end� Thickness of iron is optimized

10

Resources shared between COMET and Mu2eAl-stabilized SC magnet R&D

Superconductor R&D� US-Japan collaboration on Al-stabilized

superconductor R&D� In JFY2009

� Replicate aluminum conforming technology� Confirm yield strength of aluminum with various

additives� Successful trial production of 200 meter cable

� 15mmx4.7mm (COMET design)� In JFY2010

� Test of RIKEN test coil in FNAL� Test of ATLAS short sample stack in FNAL� Trial production of larger conductor

� 30mmx6.5mm (Mu2e design)� In JFY2011

� Plan to fabricate a test coil with 15mmx4.7mm conductor in FNAL� small diamter

� Plan to fabricate a test coil with 30mmx6.5mm conductor in Japan� 1.3 m diameter� radiation hard insulator

Design values:� Size: 4.7x15mm� Offset yield point of

Al@4K: >85MPa� RRR@0T: >500� Al/Cu/SC: 7.3/0.9/1� 14 SC strands: 1.15mm

dia.

Superconductor R&D� US-Japan collaboration on Al-stabilized

superconductor R&D� In JFY2009

� Replicate aluminum conforming technology� Confirm yield strength of aluminum with various

additives� Successful trial production of 200 meter cable

� 15mmx4.7mm (COMET design)� In JFY2010

� Test of RIKEN test coil in FNAL� Test of ATLAS short sample stack in FNAL� Trial production of larger conductor

� 30mmx6.5mm (Mu2e design)� In JFY2011

� Plan to fabricate a test coil with 15mmx4.7mm conductor in FNAL� small diamter

� Plan to fabricate a test coil with 30mmx6.5mm conductor in Japan� 1.3 m diameter� radiation hard insulator

Design values:� Size: 4.7x15mm� Offset yield point of

Al@4K: >85MPa� RRR@0T: >500� Al/Cu/SC: 7.3/0.9/1� 14 SC strands: 1.15mm

dia.

•Two kinds of SC wire with Al stabilizer•15mm x 4.7mm•30mm x 6.63mm•Coil winding in Japanese manufacturer•Testing bending procedure to form a coil•Glass-Kapton prepreg as insulator•BT resin or Epoxy•Completed by the end of March•Excitation test at FNAL•as a part of US-Japan program

Bending Tests of a Wide Conductor at Toshiba (ATLAS cable)

No problem was found in R=650No problem was found in R=650

cryostat at NHMFL,shipped to FNAL

11

[email protected] 20 PASI Fermilab January 2012

Superconducting Solenoid R&DNeutron irradiation tests performed at KURRI reactor, Kyoto University

2 Days

Demonstrated that Al stabiliser tolerates COMET

radiation environment

Resources shared between COMET and Mu2eIrradiation Test at KURRI reactor

Demonstrated that Al stabilizer tolerates COMET radiation environment.

12

Detector R&D

13


COMET Detector Section

● Straw-tube electron tracker in 1 Tesla field

● 800 kHz charged particle and 8 MHz gamma rates

● 0.4% momentum and 700 micron spatial resolution required

COMET Detector SectionStraw-Tube Tracker

•Straw-tube electron tracker in vaccum under 1 T magnetic field•800 kHz charged particles and 8 MHz gamma rate per plane•0.4 % momentum resolution and 700 micron spacial resolution

14

✤ Straw Chamber Overview - cont’d7

Hajime NISHIGUCHI (KEK) “Straw Tracker R&D at KEK” COMET CM7, Osaka U., 9-10.Jan.2012

✤ Concept4


Gas Inlet

Signal

Evacuation

HV Line

Straw Chamber(1m)

Gas Manifold

Vacuum Chamber

Preamps Gas Outlet

✤ Inserting ...11


Resources shared between COMET and Mu2eStraw Gas Chamber R&D (1)

• Prototyping of straw chambers• Construction of a vacuum

chamber• Gas manifold and front-end

electronics in place.

Tests of Straw chambersin vacuum

15

Straw Chamber R&D at KEK(Study Detail)H.Nakai,Osaka-U CM7

Raw Signal

htdc19Entries 1612

Mean 4.162e+04

RMS 24.56

Underflow 0

Overflow 0

Integral 1612

0 20 40 60 80 100 120 140310×0

100

200

300

400

500

600

700

800

900

htdc19Entries 1612

Mean 4.162e+04

RMS 24.56

Underflow 0

Overflow 0

Integral 1612

htdc19htdc20

Entries 1385

Mean 4.904e+04

RMS 1.066e+04

Underflow 0

Overflow 0

Integral 1385

0 20 40 60 80 100 120 140310×0

1

2

3

4

5

6

7htdc20

Entries 1385

Mean 4.904e+04

RMS 1.066e+04

Underflow 0

Overflow 0

Integral 1385

htdc20

htdc21Entries 1360

Mean 4.683e+04

RMS 1.082e+04

Underflow 0

Overflow 0

Integral 1360

0 20 40 60 80 100 120 140310×0

2

4

6

8

10htdc21

Entries 1360

Mean 4.683e+04

RMS 1.082e+04

Underflow 0

Overflow 0

Integral 1360

htdc21htdc22

Entries 506

Mean 4.526e+04

RMS 1.189e+04

Underflow 0

Overflow 0

Integral 506

0 20 40 60 80 100 120 140310×0

1

2

3

4

5

6htdc22

Entries 506

Mean 4.526e+04

RMS 1.189e+04

Underflow 0

Overflow 0

Integral 506

htdc22

hqdc21Entries 1612Mean 321RMS 59.4Underflow 0Overflow 0Integral 1612

0 500 1000 1500 2000 2500 3000 3500 40000

2

4

6

8

10

12

14

16

18hqdc21

Entries 1612Mean 321RMS 59.4Underflow 0Overflow 0Integral 1612

hqdc21hqdc23

Entries 1612Mean 510.8RMS 189.5Underflow 0Overflow 0Integral 1612

0 500 1000 1500 2000 2500 3000 3500 40000

2

4

6

8

10

12

14

16

18

20

22 hqdc23Entries 1612Mean 510.8RMS 189.5Underflow 0Overflow 0Integral 1612

hqdc23

hqdc25Entries 1612Mean 626.8RMS 159.1Underflow 0Overflow 0Integral 1612

0 500 1000 1500 2000 2500 3000 3500 40000

2

4

6

8

10

12

14

16

hqdc25Entries 1612Mean 626.8RMS 159.1Underflow 0Overflow 0Integral 1612

hqdc25hqdc27


0 500 1000 1500 2000 2500 3000 3500 40000

2

4

6

8

10

12

14

16hqdc27


hqdc27

QDC(very preliminary) TDC(very preliminary)

DAQ

Raw Signal

psec

180 nsec

8 mV

46 4 STATUS OF DETECTOR R&D

Figure 54: Capacitive sensors used for deformation study.

Figure 55: Capacitive sensors mounted on the prototype for deformation study.

4.2 Front-end Electronics R&D

As described in CDR[2], the front-end electronics equipped on the detector will includereadout digitization electronics for reducing the substantial cable volume and signal degra-dation during transmission through long cables. The readout system will be designed totake advantage of modern electronic design using distributed signal processing [8]. All sig-nals are digitized at the front end, and stored in digital pipelines for trigger latency. Oncea trigger is presented, only those channels having signals above a set threshold are read,stored in bu!ers, and then serially transferred to a data acquisition system outside thevacuum wall. At this point the events are rebuilt, analyzed, filtered, and finally committedto permanent storage.

Based on this thought, we started prototyping of the front-end electronics. A blockdiagram of the prototype is shown in Figure 58.

4.1 Strawtube Tracker R&D 45✤ Straw Chamber Overview - cont’d7


✤ Gas Manifold - cont’d10


Mode - A Mode - B

Front-End Electronics is placed in a manifold

Front-End Electronics is placed in vacuum

(outside manifold)

Figure 52: Strawtube tracker prototype.

Figure 53: Strawtube vacuum chamber containing the prototype.

in the COMET final detector. This is su!ciently small compared to a pumping power forthe inner volume of the detector solenoid.

Operation of the prototype as a drift chamber has just commenced. Figure 57 showsobserved charge (upper) and drift time (lower) distributions observed on wires on the up-per (left) and lower (right) layers. Detailed studies such as optimization of the operationvoltage and gas mixture, and rate dependence of the detector response will continue towardfinalization of the detector performance evaluation.

Resources shared between COMET and Mu2eStraw Gas Chamber R&D (2)

• Normal operation in air• X-t relation and spatial resolution

• Gas leak study• Over-pressurized study

• 2 atom.• Deformation study

• capacitive sensor• Operation in vacuum

• just started...

Tests of Straw chambersin vacuum

Raw signal without amp.

Deformation study by capacitive sensor

front-end electronicsin a manifold

16

Resources shared between COMET and Mu2eFrontend Electronics R&D

Front-‐end:ASDGiga bit Ether

FPGA

Analog memory：DRS4

Signal fromstraw tube１２ｃｍ

１７ｃｍ

16ch/1board

• Front-end electronics for straw trackers and crystal calorimeter. • wave-form sampling based on switched capacitor array (DRS4)• a prototype board is constructed and tested with the KEK

electronics group.

17

COMET Detector SectionCrystal Calorimeter

•Energy and position measurements, PID, trigger signal•5% energy and 1 cm spatial resolution at 100 MeV


COMET Detector Section

● Crystal calorimeter

● for energy and position measurement, PID, trigger signal

● 5% energy and 1cm spatial resolution at 100 MeV

18

50 x GSO(Ce) (20x20x120mm3 by Hitachi Chemi.)

9 x LYSO (20x20x150mm3 by Dubna (Saint-Gobain))

Pream

ps

for 50ch(Yuri’s circuit)

Waveform

digitizer

(ex. CA

EN

V1742)

DA

Q P

C(M

IDA

S)

with APD ( and light guide)

and wrapping

Logger

Th

erm

isto

rs

HV

PSDC

5V

Pream

ps

for 9ch(Yuri’s circuit)

Th

erm

.

Trigger Scinti.

Trigger Scinti. for CR

The detail was shown in the Dima’s talk.

h1Entries 35748Mean 6.622e+04RMS 2.842e+04Underflow 0Overflow 3

ns)!par[3] (ch 0 50 100 150 200 250 300 350 400

310!

(cou

nts)

1

10

210

h1Entries 35748Mean 6.622e+04RMS 2.842e+04Underflow 0Overflow 3

run1121:par[3]

6.1MeV

2.6MeV

Resources shared between COMET and Mu2eElectron Calorimeter R&D

Calorimeter Prototyping R&D


Calorimeter R&D● GSO / LYSO crystals with APDs tested 2011

● Vertical slice tests this year

● Design being finalised for 50-

crystal / APD prototype

● beam tests later this year at

BINP Novisibirsk

LaBr3

LYSO• Single crystal test has been done at BINP.

• Prototypes for GSO and LYSO crystal array are planned.

• Beam tests at BINP in summer and winter, 2012.

typical spectrum for LYSO and APD (10x10 mm2)

19

8 2 COSMIC RAY SHIELDING DESIGN

The fibers are mirrored at the rear end; the scintillation light is read out at the other endwith a Silicon Photomultpliers with a 1.3! 1.3 mm2 active area. We consider two possibletypes of SiPM; MPPC from Hamamatsu Photonics [4] and Russian made MRS APD [5](see Figure 6). The SiPM, either of MPPC or MRS APD, is mounted on a strip with aspecial plastic connector that fixes its position and guarantees a small air gap to the fiberas shown in Figyre 7.

YHU\KLJKHIILFLHQF\HYHQZLWKDKLJKOHYHOWKUHVKR

Figure 6: View of 796 pixel MRS APD fiber (CPTA, Russia).

The proposed strip design has the following advantages over a wider strip with severalWLS fibers:

• Light from a MIP is not shared between di!erent SiPMs. This allows to have a veryhigh e"ciency even with a high level threshold. Our measurements demonstrate thatthe e"ciency for MIP for the worst case of particle crossing far end of the strip islarger than 99 % with a threshold at 7 pixels equivalent (see Figure 8). As it will beshown below at such threshold the MPPC noise is less than 10 Hz, i.e. is below therate of cosmic rays. Dependence of the strip light yield to MIP versus the distance tophoto-detector is shown in Figure 9. Fig.ure 10 shows the SiPM noise rate distributionwith a 7 pixels threshold for more than 200 Hamamatsu MPPCs.

• It is easier to estimate the e"ciency of each strip with cosmic muons using coincidenceswith other strip signals.

• In case of problems with one channel only a small part of the detector is a!ected.

• Time resolution of about 1 nsec can be achieved easily.

For each module SiPMs are read out by 15 channels of di!erential preamplifiers (seeFigure 11), that allows to transfer the signals over a large distance. This preamplifier hasbeen tested; a compact 15 channel layout will be developed soon.

Resources shared between COMET and Mu2eR&D on Cosmic Ray Veto System

• The active cosmic ray veto system is based on plastic scintillator with fiber readout.

• Photosensors are MRS APD or MPPC.• Designed by the BINP (Novosibirsk) and ITEP

(Moscow) groups.• Strip 0.7x4x300 cm3 scintillator made by

Uniplast (Russia).• The light yield at a far end is even 15 pe. The

counter efficiency for MIP is 99.7% with 55 pixel threshold.

796 pixel MRS APD fiber (CPTA, Russia).

20

• To monitor a number of stopping muons, muonic X-rays from the muon stopping target (made of aluminum) is to be measured.

• Two different detectors, Ge and CdTe were tested at the J-PARC MLF muon facilities in fall, 2010.

• Detector efficiencies and transition rates are studied.

• R&D on Multi-pixel detectors is being done.

• Location of the muonic X-ray detectors at COMET is being studied.

Ge detector’s Result - Al target

Measuring time: 216minMuon momentum:10-16 MeV/c(decay muon)

20

CdTe detector

EURORAD,Ohmic type10mm×10mm×3mm

Ge detector

Ortec,POPTOPtype,GMXφ=50mm,length=50mm

X-ray detectors at Beam test

15

Theoretical predictions muonic X-ray energy(kev)

(emission rate)

CdTe detector’s Result - Al target

Kα Kβ Kγ Lα Lβ Lγ

C 75keV(0.604)

89keV(0.102)

94keV(0.083) - - -

N 102keV(0.763)

122keV(0.067)

128keV(0.029) - - -

O 134keV(0.735)

159keV(0.070)

168keV(0.030) - - -

Al 347keV(0.811)413keV(0.058)

436keV(0.019)

66keV(0.422)

89keV(0.072)

100keV(0.031)

Fit function

Al-Lα & C-Kα

Al-Kα

19

Resources shared between COMET and Mu2eR&D on Muon Monitor System

Measured muonic X-rays from aluminum21

COMET_G4

22

Resources shared between COMET and Mu2eCOMET_G4 (Geant Simulation)

[email protected] 14 COMET Collaboration Meeting January 2012

Full Field Map and Geometry Alignment

mm

mmT


Before Stopping Target

{20 0 20

y [cm]

y [cm]

{20 0 20 x [cm]

20

0

{20

20

0

{20

Ben Krikler

after collimation of

high-momentum

muons

at muon stopping [email protected] 2 PASI Fermilab January 2012

Fluxes at Entrance to Curved Solenoid

{20 0 20

y [cm]

y [cm]

{20 0 20 x [cm]

Ben Krikler

20

0

{20

20

0

{20

at [email protected] 3 PASI Fermilab January 2012

After 90 Degrees of Curved Solenoid

{20 0 20

y [cm]

y [cm]

{20 0 20 x [cm]

20

0

{20

20

0

{20

Ben Krikler

3 T solenoid

field,

0.018 T

dipole field

(tunable)

at 90 degree bending

•Full 3D field mapping (from Toshiba) is introduced.

•Mass data production has been made.

23

COMET Collaboration

24

Resources shared between COMET and Mu2eCOMET Collaboration List2

The COMET Collaboration

R. Akhmetshin, A. Bonder, L. Epshteyn, G. Fedotovich, D. Grigoriev, V. Kazanin,A. Ryzhenenkov, D. Shemyakin, Yu. Yudin

Budker Institute of Nuclear Physics (BINP), Novosibirsk, Russia

Y.G. Cui, R. PalmerDepartment of Physics, Brookhaven National Laboratory, USA

Y. Arimoto, K. Hasegawa, Y. Igarashi, M. Ikeno, S. Ishimoto, Y. Makida, S. Mihara,T. Nakamoto, H. Nishiguchi, T. Ogitsu, C. Omori, N. Saito, K. Sasaki, M. Sugano,Y. Takubo, M. Tanaka, M. Tomizawa, T. Uchida, A. Yamamoto, M. Yamanaka,

M. Yoshida, Y. Yoshii, K. YoshimuraHigh Energy Accelerator Research Organization (KEK), Tsukuba, Japan

Yu.BagaturiaIlia State University (ISU), Tbilisi, Georgia

P. Dornan, P. Dauncey, U. Egede, B. Krikler, A. Kurup, J. Pasternak, Y. Uchida,Imperial College London, UK

P. Sarin, S. Umasankar,Indian Institute of Technology Bonbay, India

Y. IwashitaInstitute for Chemical Research, Kyoto University, Kyoto, Japan

V.V. Thuan,Institute for Nuclear Science and Technology, Vietnam

M. Danilov, A. Drutskoy, V. Rusinov, E. Tarkovsky,Institute for Theoretical and Experimental Physics (ITEP), Russia

H.-B. Li, C. Wu,Institute of High Energy Physics (IHEP), China

S. Dymov, P. Evtoukhovich, V. Kalinnikov, A. Khvedelidze, A. Kulikov, G. Macharashvili,A. Moiseenko, B. Sabirov, V. Shmakova, Z. Tsmalaidze

Joint Institute for Nuclear Research (JINR), Dubna, Russia

Y. Mori, Y. Kuriyama, J.B. LagrangeKyoto University Research Reactor Institute, Kyoto, Japan

W.A. Tajuddin,University of Malaya, Malaysia

M. Aoki, T. Hiasa, I.H. Hasim T. Hayashi, Y. Hino, S. Hikida, T. Itahashi, S. Ito,Y. Kuno!, T.H. Nam, H. Nakai, H. Sakamoto, A. Sato, N.D. Thong, N.M. Truong

Osaka University, Osaka, Japan

M. Koike, J. SatoSaitama University, Japan

3

A. Liparteliani, N. Mosulishvili, Yu. Tevzadze, I. Trekov, N. TsveravaInstitute of High Energy Physics of I.Javakhishvili State University (HEPI TSU), Tbilisi,

Georgia

D. BrymanUniversity of British Columbia, Vancouver, Canada

S. Cook, R. D’Arcy, M. Lancaster, M. WingUniversity College London, UK

E. HungerfordUniversity of Houston, USA

T. NumaoTRIUMF, Canada

* Contact Person

25






















3


Georgia





* Contact Person

new collaborators

25






















3


Georgia





* Contact Person

new collaborators

COMET was approved as a project at JINR in 2011.

25

Resources shared between COMET and Mu2eCOMET Organization

• The “COMET Constitution” has been written and agreed. • The COMET organization is defined.• The COMET organization will be formed and started in the next

collaboration meeting.

spokesperson project manager@KEK

EditorialBoard

SpeakerBureau

Executive Board

Collaboration Board

COMET Organization

26

On MTF Proposal (COMET Staging Plan)

27

Beam line plan at southern area

with COMET beam line

Resources shared between COMET and Mu2eMTF Proposal on COMET Beam Line

• MTF and JPNC’s proposal on the beam lines at the south area.

from Tanaka-san’s slides in this J-PARC PAC.28

Beam line plan at southern area

with COMET beam line

Resources shared between COMET and Mu2eMTF Proposal on COMET Beam Line

• MTF and JPNC’s proposal on the beam lines at the south area.

from Tanaka-san’s slides in this J-PARC PAC.28

Resources shared between COMET and Mu2eCOMET Muon Beam Line

COMET wishes to have the first 90 degrees of the muon transport curved solenoids (which are located inside concrete shields) in this proposal, since the installation of these magnets would become difficult after activation by a proton beam.

up to here29

Resources shared between COMET and Mu2eCOMET Staging Plan

COMET Phase-I

30


(1) Study for the COMET full experiment•Measurement of secondary particle production•Measurements of muon yield, •Measurements of backgrounds from pions, electrons, neutrons,

kaons, and anti-protons.•Muon beam tuning

COMET Phase-I

Page 4

Background Working Group Status

COMET Collaboration Meeting 7 9th January 2012 Ajit Kurup

CDR

Background estimation in CDR30




(2) Physics experiments• µ-+ N →e- + N conversion• µ-+ N →e+ + N conversion• µ-+ e- →e- + e-

COMET Phase-I

1

10

102

103

80 90 100eve

nts

/ c

ha

nn

el

Class 1 events: prompt forward removed

µe simulation

MIO simulation

e+ measurement

e- measurement

1

10

80 90 100

Class 2 events: prompt forward

momentum (MeV/c)

SINDRUM II

configura

tion 2

000

1m

A

B

CD ED

F

G

H

H

I

J

A

B

C

D

E

F

G

H

I

J

exit beam solenoid

gold target

vacuum wall

scintillator hodoscope

Cerenkov hodoscope

inner drift chamber

outer drift chamber

superconducting coil

helium bath

magnet yokeSINDRUM II

Final result on mu - e conversion on Gold

target is being prepared for publication

< 7 x 10-13 90%CL

@ PSI

Detector is being studied.Its cost can mostly be covered by

the COMET collaboration.31




(2) Physics experiments• µ-+ N →e- + N conversion• µ-+ N →e+ + N conversion• µ-+ e- →e- + e-

COMET Phase-I

1

10

102

103

80 90 100eve

nts

/ c

ha

nn

el

Class 1 events: prompt forward removed

µe simulation

MIO simulation

e+ measurement

e- measurement

1

10

80 90 100

Class 2 events: prompt forward

momentum (MeV/c)

SINDRUM II

configura

tion 2

000

1m

A

B

CD ED

F

G

H

H

I

J

A

B

C

D

E

F

G

H

I

J

exit beam solenoid

gold target

vacuum wall

scintillator hodoscope

Cerenkov hodoscope

inner drift chamber

outer drift chamber

superconducting coil

helium bath

magnet yokeSINDRUM II

Final result on mu - e conversion on Gold

target is being prepared for publication

< 7 x 10-13 90%CL

@ PSI

plan to submit a LOI for the July PAC. Detector is being studied.

Its cost can mostly be covered by the COMET collaboration.

31

Summary

33

Summary

34

Summary

COMET collaboration will submit the COMET TDR, which is almost ready, to the March J-PARC PAC.

34

Summary


COMET collaboration asks J-PARC PAC to supportthe COMET staging approach.

34

Summary


COMET collaboration asks J-PARC PAC to supportthe COMET staging approach.

COMET collaboration will submit a LOI of COMET Phase-I to the July J-PARC PAC.

34

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