MICE (1) MICE Shigeru Ishimoto (KEK) (2) and (3) - - PowerPoint PPT Presentation

RCNP研究会「ミューオン科学と加速器研究」 OCT-20, 2008

Shigeru Ishimoto (KEK) and MICE Collaboration

ミューオンビームイオン化冷却実証実験

MICE

(1) MICEの紹介 (2) 液体水素アブソーバー (3) 液体水素アブソーバーR&D (4) RF, Tracker, …etc. (5) 現状とスケジュール（まとめ）

Neutrino Factory

µ

+ µ– Collider

• R. Palmer et. al.

Ionisation Cooling

• Pass muons through absorbers  dE/dX reduces pt and pl
• RF replaces pl  beam cooled; scattering heats
• Transverse emittance decreases exponentially
• ~ 200 MeV/c is about optimum

Bethe-Bloch

dE/dX : Large Rad.Length X0; small H2, LiH, He …

MICE概要
 （Muon Ionization Cooling Experiment）

• ミューオン加速・蓄積に必要なイオン化冷却を実証する
• 素早い冷却のために

– 高電場加速空胴の開発

• ~10MV/m
• 低い周波数（２００MHz）

– 軸方向アクセプタンスを確保する

– 液体水素減速材

• 多重散乱によるエミッタンスの増加を抑える
• 安全な冷却装置の開発
• ビームウインドウの改良
• 冷却前後でエミッタンスの減少を確認する測定器を置く

– 0.1%の精度でエミッタンスを測定する

• 冷却用コンポーネントの製作可能性のチェック
• 運転時のバグ出し、最適化

MICEの目標(測定器)

• 10～15%のエミッタンスの減少を１％(絶対値で0.1%)の

精度で測定する。

• 冷却チャンネルの前後におけるエミッタンスを0.1%の精度で

測定できるスペクトロメータ

• 一粒子ごとに飛跡を検出
• バックグランドパイ粒子・電子を除くためのPID検出器
• 粒子検出器群と冷却チャンネルを統合する
• 多重散乱を防ぐため検出器内部の物質量を減らす
• 高磁場、高バックグランド条件下で安定に動作すること

MICE コラボレーション

ヨーロッパ Louvain la Neuve, Saclay, Bari, LNF Frascati, Genova, Legnaro, Milano, Napoli, Padova, Roma III, Trieste, NIKHEF, Novosibirsk, CERN, Genève, ETH Zurich, PSI, Brunel, Edinburgh, Glasgow, Imperial College, Liverpool, Oxford, RAL, Sheffield 日本 Osaka, KEK, Kyoto LH2 Absorber, Sci-Fi Tracker, … 中国 ICST アメリカ ANL, BNL, FNAL, IIT, Chicago Enrico Fermi Inst., LBNL, UCLA, NIU, Mississippi, Riverside Collaboration Meeting 22 ; Oct 19-21 ’08 at RAL Collaboration Meeting 23 ; Jan ’08 at ICST 国際共同： 39機関

ヒストリー

• 2001年：NuFact’01（つくば）において提案
• 2002年：Letter of Intentを英国ラザフォード研究所（RAL）に提

出

• 2003年1月：Proposal をRALに提出
• 2003年3月：国際レビュー委員会から “strongly

recommended” と評価される

• 2003年10月：CCLRC chief executiveが計画の重要性を承認
• 1st UK Project Review (Gateway)
• 2004年末：2nd UK Project Review
• 2008年：First Beam STEP I

RAL / ISIS

MICE

MICE Setup

MICE cooling channel

Drawing by S. Q. Yang

Tracker Module 1 Tracker Module 2 AFC Module 1 AFC Module 3 AFC Module 2 RFCC Module 1 RFCC Module 1

µ µ BEAM

MICE cooling channel

Expected Performance of MICE

Single particle experiment  Measure amplitude distributions  Demonstrate cooling  Measure transmission Change in emittance: Δε Δε / / ε = (Δp/p )( 1-ε0/ε ) Δp ~ 5% in each absorber  15% cooling for large εin

Amplitude Before & After Emittance

AFC (Absorber & Focus Coil) module

Cryomech PT415 cooler (1.5W@4.2K) LH2 condenser Safety windows absorber windows

G-10 Support Absorber & Pipes Mini In-Flange (Al-SS) 30 Pin Feedthrough Tee  L-H2 IN G-H2 OUT G-He/N2 OUT L-He/N2 IN

A-A’

(22.5 deg.) G-H2 OUT  L-H2 IN G-He/N2 OUT LHe/LN2 IN Tee 30 Pin Feedthrough Heat- exchanger LH2 LH2

MIRAPRO Co.

Liquid-hydrogen absorber

Flange of MICE absorber

Design window; Oxford Design flange; KEK Machining ; Mississippi Tolerance between flange and body: 0.1-0.3 mm

G-10 (x8) t=1, W=25, L=90 mm Total ~ 0.2 W

SS, t=1

Screws on AFC Magnet

7 6.5

34

SS φ15.7 AL φ14.8

34

From Absorber

Small flange and G-10 support

Tee and 30 pin feedthrough

In seal Kyocera 30 pin feedthrogh

LH2 In to absorber

10 Cernox 1050SD 4 wires; AB101, 102, 105, 109,110 2 wires; AB103,104,106,107,108 (Total 5*4 + 5*2 = 30 wires) Im=0.1 mA; 101,103,105,107,109 Im=1 mA; 102,104,106,108,110

Temperature & level sensors in the absorber

In LH2

• ver heating

mode in gas

Prototype absorber

MICE absorber test at KEK

1,959

T.M.P.

G-M Cryocooler 1.5W@4.2K

LH2 condenser Dummy bore (room temperature)

Prototype absorber

Prototype absorber test at KEK

0.30 l / h , 2.6 W 1.33 l / h , 11.7 W

2000 l tank

Cooling stop

LH2 1.43 l

 68 hrs to fill 20 l

Liquefaction and vaporization of LH2 in 20 l Absorber

LH2 Level Sensor in the Absorber

H2 vapor

Cernox calibration curve

H2 Press (Torr) n-H2 Temp.(K) e-H2 Temp.(K) Absorber Temp.(K)

T (K) DAY

MICE absorber test at KEK

Hull cooling Water/Glycol Inlet, 1” Hull cooling Water/Glycol Outlet, 1”

Dia 470 1590

Hydrogen connection with shut-off valve and safety valve Internal cooling Water/Glycol Inlet/Outlet Top removable thermal insulation cover

1680 Nominal capacity: 2450 g (27 Nm3) H2 Volume of overall storage tank: 250 litres Overall weight: 375 kg

Metal Hydride Storage Tank

PT415 Pulse Tube

Displacer <0.08 T perpendicular Displacer <0.3 T parallel Displacer Motor <0.08 T Valve Motor <0.1 T Regenerator <1.5 T

Cryocololers for MICE

Tracker Magnet Cold Mass w/o Cover

The space outside of the coils is filled with 200 liters of helium.

Space for LHe Coil E2 Coil M1 Coil M2 Coil E1 Center Coil

Tracker Magnet Cold Mass with Welded Cover Magnet cooling is between the cover plate and the coils. The space inside is filled with liquid helium. The cool down gas flows in the same space. The cover plate gets colder faster than the magnet mandrel and the coils.

Tracker Magnet He Feed and Vent

PT-415 Cooler Ball Valves for Cool Down Relief Valves Rupture Disc PT-415 Cooler Valve

Vacuum Vessel and Support Stand

Vacuum vessel ready for assembly with cold mass

The ICST Coupling Solenoid Design

Coupling Magnet Cryostat Coupling Magnet Cold Mass

ICST Cryogenic Test Facility

The ICST test facility is designed for cooling down and training the large coils (including the finished MICE and MuCool coupling coils). ICST Linde Refrigerator for Testing ICST Valve Box for Test Facility

Large Test Coil (Test Coil 2) Progress

Welding the Test Coil 2 Mandrel Test Coil 2 Finished Mandrel Mounted on the ICST Coil Winding Machine

Eight 201-MHz Cavities for MICE

RFCC Module

SC coupling Coil Vacuum Pump Curved Be window

201 MHz Cavity Concept

Spinning of half shells using thin copper sheets and e-beam welding to join the shells; extruding of four ports; each cavity has two pre-curved Beryllium windows, but also accommodates different windows

• Each cavity has two Be windows

– 42-cm diameter and 0.38-mm thick – Window is formed at high temperature and later brazed to copper frames – Thin TiN coatings on both sides of the window

• One window curves into the cavity and one curves out
• Already high power tested up to 5 MW in 201-MHz cavity at

MTA, FNAL

Thin and Curved Be Windows

201 MHz Cavity

Pb Diffuser

mechanics electronics/control/air system plans effort conclusions

SciFi 飛跡検出器

• 5 SciFi Station
• Station は 3 view (V,X,W) から成る。

それぞれのviewは120°の角度で重 ねる。

• 1 view は 1491 本の 350ミクロン

ファイバーから成る。

– 420ミクロンピッチ / 2層俵積み – 7本ずつ（1.5mm幅）まとめ読みして エレキのチャンネルを減らす。

• ４ｍ長クリアファイバーでVLPCまで導

く

30cm Edge of layer Layout of Sci-fi station

44

Tracker Photographs

5 tracker stations Connecting waveguide fibers All waveguide fibers organized and bundled Tracker, waveguide fibers, and patch panel all assembled Only one dead channel

Terry Hart, MICE CM 20, February 10, 2008

45

MICE Tracker 2 Cassette Characterization, Firmware Update,

• Status of Tracker 2 Cassette Characterization
• Further Firmware Optimizations at IIT
• Summary and Plans

Terry Hart, MICE CM 22, October 19, 2008

Current MICE

Thank you

Hokusai Katsushika “Hydrangea and Swallow”

MICE Step I

• Target needs redesign and proof of functionality – limited

number of target dips available for commissioning, beam studies, and physics

• There exists a question on how many muons we will really

get…

• Decay Solenoid – coil 10 dead – not going SC

– Problem is currently unknown – need to find problem and then fix it… costs time

• Diffuser not here - ?needed for Step 1?
• Q4,5,6 leaking water – not able to run
• TOF1 not here & apparently not working

• Assuming Step I is complete, then:
• Spectrometer Magnets – will get the first one by November?

– Should definitely go to Fermilab for magnetic field measurements before shipping to RAL – Note: Also need to measure field in MICE hall – questions exist regarding North/South shielding wall effects on magnetic field

• Tracker1

– Testing in R8 good idea and going well – Debugging occuring – DAQ implementation and firmware changes ongoing – Need to test Tracker2 in the same way

• Might be able to have Step II relatively soon after running in Step I

configuration

MICE Step II

MICE Target MICE RAL / ISIS

MICE Experiment