P.-R Kettle MEG Review July 2005 1 Beam Transport & Target Systems BTS Success Novosibirsk 24/5/2005 18:15 300 A 300 A

P.-R KettleP.-R Kettle MEG Review July 2005MEG Review July 2005 11

Beam Transport & Target SystemsBeam Transport & Target SystemsBeam Transport & Target SystemsBeam Transport & Target Systems

BTS SuccessBTS SuccessNovosibirskNovosibirsk

24/5/2005 18:1524/5/2005 18:15

300 A300 A


Beam Line & Target StatusBeam Line & Target Status

Topics to be Addressed:

• Beam Transport System(i) Degrader / BTS optimization (ii) Layout - fixed

• Beam Line Components Status * (i) Separator- undergoing HV-conditioning * (ii) Beam Transport Solenoid BTS – being commissioned E5

(iii) Vacuum System (beam line + BTS)- being assembled(iii) Cryogenic Transfer Lines LN2 LHe – installed

• He-Bag & Target Systems

• Schedule 2005

• Summary + Critical Points

Topics to be Addressed:

• Beam Transport System(i) Degrader / BTS optimization (ii) Layout - fixed

• Beam Line Components Status * (i) Separator- undergoing HV-conditioning * (ii) Beam Transport Solenoid BTS – being commissioned E5

(iii) Vacuum System (beam line + BTS)- being assembled(iii) Cryogenic Transfer Lines LN2 LHe – installed

• He-Bag & Target Systems

• Schedule 2005

• Summary + Critical Points


Beam Transport System Beam Transport System StatusStatusBeam Transport System Beam Transport System StatusStatus


Beam Transport SystemBeam Transport SystemBeam Transport SystemBeam Transport System

As previously reportedBeam Line Commissioning2004 concluded withphase space measurementsIn vacuum up to theINJECTION into the BTSINJECTION into the BTS (without BTS !!!)(without BTS !!!)

As previously reportedBeam Line Commissioning2004 concluded withphase space measurementsIn vacuum up to theINJECTION into the BTSINJECTION into the BTS (without BTS !!!)(without BTS !!!)

Using real data Using real data SIMULATE Phase Space & Back-Track to Triplet II SIMULATE Phase Space & Back-Track to Triplet II Forward-Track with Fringe Field of BTS + COBRA up to Target in Forward-Track with Fringe Field of BTS + COBRA up to Target in COBRACOBRA using GEANTusing GEANT

Input Data to GEANT Input Data to GEANT to study to study Degrader/Target + BTS/COBRA layout Degrader/Target + BTS/COBRA layout Input Data to GEANT Input Data to GEANT to study to study Degrader/Target + BTS/COBRA layout Degrader/Target + BTS/COBRA layout

““waist”waist”


Degrader + BTS/COBRA OptimizationDegrader + BTS/COBRA OptimizationDegrader + BTS/COBRA OptimizationDegrader + BTS/COBRA Optimization

Beam Sigma at COBRA Focus vs. BTS Bfield & Gap

10.0

11.0

12.0

13.0

14.0

15.0

16.0

17.0

18.0

-3.8 -3.7 -3.6 -3.5 -3.4 -3.3 -3.2 -3.1

BTS Bfield [kG]

Bea

m S

igm

a [m

m]

M aximum (-/+) DDD+W

Intermediate DDD+W

M inimum DDD+W

M aximum (+/+) DDD+W

Studied:Studied:

1.1. BTS/COBRA Distance vs. Degrader segmentation & BfieldBTS/COBRA Distance vs. Degrader segmentation & Bfield (Cryo.-Cryo. Gap): (Cryo.-Cryo. Gap): minimum (200 mm), intermediate(300 mm), maximum(400 mm)minimum (200 mm), intermediate(300 mm), maximum(400 mm)

2.2. BTS/COBRA Polarity BTS/COBRA Polarity (+/+), (-/+) radial de-focussing/focussing(+/+), (-/+) radial de-focussing/focussing

Studied:Studied:

1.1. BTS/COBRA Distance vs. Degrader segmentation & BfieldBTS/COBRA Distance vs. Degrader segmentation & Bfield (Cryo.-Cryo. Gap): (Cryo.-Cryo. Gap): minimum (200 mm), intermediate(300 mm), maximum(400 mm)minimum (200 mm), intermediate(300 mm), maximum(400 mm)

2.2. BTS/COBRA Polarity BTS/COBRA Polarity (+/+), (-/+) radial de-focussing/focussing(+/+), (-/+) radial de-focussing/focussing

Max. B+veMax. B+veMax. B+veMax. B+ve

Max. B-veMax. B-veMax. B-veMax. B-ve

Beam Sigma at COBRA Focus vs. BTS Bfield Normal Gap

10.0

11.0

12.0

13.0

14.0

15.0

16.0

17.0

18.0

19.0

-3.9 -3.8 -3.7 -3.6 -3.5 -3.4 -3.3 -3.2 -3.1 -3

BTS Bfield [kG]

Bea

m S

igm

a [m

m]

DDDD

DDD+W

DD+W+D

D+W+DD

W+DDD

• Weak Gap dependence (4%) Weak Gap dependence (4%) • strong polarity dependencestrong polarity dependence (15%)(15%)

• Weak Gap dependence (4%) Weak Gap dependence (4%) • strong polarity dependencestrong polarity dependence (15%)(15%)

• strong degrader segmentationstrong degrader segmentation dependence (25%)dependence (25%)

• strong degrader segmentationstrong degrader segmentation dependence (25%)dependence (25%)

• Gap 400 mmGap 400 mm• -/+ Polarity-/+ Polarity• Degrader BTSDegrader BTS

GapGap


Beam Transport System LayoutBeam Transport System LayoutBeam Transport System LayoutBeam Transport System Layout

SepSepSepSep

Trip ITrip ITrip ITrip I Trip IITrip IITrip IITrip II

ASCASCASCASC

BTSBTSBTSBTS

COBRACOBRACOBRACOBRA

XXXX

YYYY

Distances Fixed: Platform + COBRADistances Fixed: Platform + COBRA surveyed into Zonesurveyed into Zone

Distances Fixed: Platform + COBRADistances Fixed: Platform + COBRA surveyed into Zonesurveyed into Zone


Beam Line Component Beam Line Component StatusStatusBeam Line Component Beam Line Component StatusStatus


Component Status: SeparatorComponent Status: SeparatorComponent Status: SeparatorComponent Status: Separator

Beam Beam Upstream Upstream SideSide

2371 mm2371 mmPropertiesPropertiesVVmaxmax 200kV 200kV

DDplatesplates 19cm 19cm

LLeff eff 70cm 70cm

PropertiesPropertiesVVmaxmax 200kV 200kV

DDplatesplates 19cm 19cm

LLeff eff 70cm 70cm

MEG Vertical SeparatorMEG Vertical SeparatorDelayed by ~ 8 weeks:Delayed by ~ 8 weeks:

• due to HV feed-through problems – due to HV feed-through problems – now solvednow solved• HV (+ve) supply changed to (–ve) one - HV (+ve) supply changed to (–ve) one - technicaltechnical HV-electrode on top, want eHV-electrode on top, want e++ deflected down deflected down

!!! HV Conditioning Tests in front of !!! HV Conditioning Tests in front of E5 !!!E5 !!! expected ready for beam timeexpected ready for beam time

MEG Vertical SeparatorMEG Vertical SeparatorDelayed by ~ 8 weeks:Delayed by ~ 8 weeks:

• due to HV feed-through problems – due to HV feed-through problems – now solvednow solved• HV (+ve) supply changed to (–ve) one - HV (+ve) supply changed to (–ve) one - technicaltechnical HV-electrode on top, want eHV-electrode on top, want e++ deflected down deflected down

!!! HV Conditioning Tests in front of !!! HV Conditioning Tests in front of E5 !!!E5 !!! expected ready for beam timeexpected ready for beam time

April 2005April 2005 May 2005May 2005 June 2005June 2005


Component Status BTSComponent Status BTSComponent Status BTSComponent Status BTS

Beam Transport Solenoid BTSBeam Transport Solenoid BTS

Schedule delayed by ~ 7 weeks:Schedule delayed by ~ 7 weeks:• 5 weeks delay during manufacture5 weeks delay during manufacture• 2 weeks transportation 2 weeks transportation (papers stolen at Russian border)(papers stolen at Russian border) neverthelessnevertheless !!! Novosibirsk Crew did a “Very Good Job” !!!!!! Novosibirsk Crew did a “Very Good Job” !!! BTS arrived PSI 8th JulyBTS arrived PSI 8th July

Beam Transport Solenoid BTSBeam Transport Solenoid BTS

Schedule delayed by ~ 7 weeks:Schedule delayed by ~ 7 weeks:• 5 weeks delay during manufacture5 weeks delay during manufacture• 2 weeks transportation 2 weeks transportation (papers stolen at Russian border)(papers stolen at Russian border) neverthelessnevertheless !!! Novosibirsk Crew did a “Very Good Job” !!!!!! Novosibirsk Crew did a “Very Good Job” !!! BTS arrived PSI 8th JulyBTS arrived PSI 8th July

Coil Manufacture - epoxyingCoil Manufacture - epoxyingCoil Manufacture - epoxyingCoil Manufacture - epoxying

End March 2005End March 2005 End May 2005End May 2005

Performance Tests – Novosibirsk Performance Tests – Novosibirsk Performance Tests – Novosibirsk Performance Tests – Novosibirsk

Novosibirsk CrewNovosibirsk Crew


BTS Performance Tests - NovosibirskBTS Performance Tests - NovosibirskBTS Performance Tests - NovosibirskBTS Performance Tests - Novosibirsk

Performance TestsPerformance Tests BINP Novosibirsk 21-29BINP Novosibirsk 21-29thth May 2005 May 2005Tested:Tested:• maximum Design Current maximum Design Current (300 A)(300 A)• Quench Detection / Protection SystemsQuench Detection / Protection Systems (fast switch 30 ms + 0.7(fast switch 30 ms + 0.7 Shunt Resistor 90% power load) Shunt Resistor 90% power load)• Linearity Response Linearity Response (max. dev. ~ 0.4%)(max. dev. ~ 0.4%)• LHe Consumption Rate LHe Consumption Rate (3.6 l/hr)(3.6 l/hr)• Magnetic Field MeasurementsMagnetic Field Measurements

Performance TestsPerformance Tests BINP Novosibirsk 21-29BINP Novosibirsk 21-29thth May 2005 May 2005Tested:Tested:• maximum Design Current maximum Design Current (300 A)(300 A)• Quench Detection / Protection SystemsQuench Detection / Protection Systems (fast switch 30 ms + 0.7(fast switch 30 ms + 0.7 Shunt Resistor 90% power load) Shunt Resistor 90% power load)• Linearity Response Linearity Response (max. dev. ~ 0.4%)(max. dev. ~ 0.4%)• LHe Consumption Rate LHe Consumption Rate (3.6 l/hr)(3.6 l/hr)• Magnetic Field MeasurementsMagnetic Field Measurements

Flexible Cryogenic Design via:Flexible Cryogenic Design via:• dedicated transfer lines (PSI)dedicated transfer lines (PSI)• dewar operation (BINP)dewar operation (BINP)• both (emergency)both (emergency)

Flexible Cryogenic Design via:Flexible Cryogenic Design via:• dedicated transfer lines (PSI)dedicated transfer lines (PSI)• dewar operation (BINP)dewar operation (BINP)• both (emergency)both (emergency)

0.70.7 Shunt Resistor Shunt Resistor All measurements &All measurements & tests successfultests successful exceptexceptBfield measurementsBfield measurementswhich were influencedwhich were influenced by by steel support structuresteel support structure

All measurements &All measurements & tests successfultests successful exceptexceptBfield measurementsBfield measurementswhich were influencedwhich were influenced by by steel support structuresteel support structure


Results BTS Performance Tests - NovosibirskResults BTS Performance Tests - NovosibirskResults BTS Performance Tests - NovosibirskResults BTS Performance Tests - Novosibirsk

Component Field Linearity

y = -18.538x - 8.7679

R2 = 1

y = 18.539x + 8.8368

R2 = 1

-8000

-6000

-4000

-2000

0

2000

4000

6000

8000

0 50 100 150 200 250 300 350

BTS Current [A]

BTS

Bfiel

d [G

]

Bx

By

Bz

Bsum

Linear(Bz)Linear(Bsum)

Field Map BTS Test 200A Btot vs. Z

0

500

1000

1500

2000

2500

3000

3500

4000

-600 -100 400 900 1400

Axial Position wrt Cryostat [mm]

Bfi

eld

B

tot

[G]

Theoretical

Measured

Main SpecificationsMain SpecificationsLLCryoCryo 2810 mm 2810 mm

DDBoreBore 380 mm 380 mm

DDCoilCoil 469.5 / 466.2 mm 469.5 / 466.2 mm

LLCoilCoil 2630 mm 2630 mm

BBMaxMax <0.55 T <0.55 T

IImaxmax 300 amps 300 amps

LLMaxMax 0.98 H 0.98 H

EEStoredStored 44 kJ 44 kJ

Main SpecificationsMain SpecificationsLLCryoCryo 2810 mm 2810 mm

DDBoreBore 380 mm 380 mm

DDCoilCoil 469.5 / 466.2 mm 469.5 / 466.2 mm

LLCoilCoil 2630 mm 2630 mm

BBMaxMax <0.55 T <0.55 T

IImaxmax 300 amps 300 amps

LLMaxMax 0.98 H 0.98 H

EEStoredStored 44 kJ 44 kJ

Coils:Coils:• double layerdouble layer• cable dia. 1.23 mmcable dia. 1.23 mm• 1865 / 1980 windings1865 / 1980 windings• 40% NiTi40% NiTi• RRR ~ 100RRR ~ 100

Coils:Coils:• double layerdouble layer• cable dia. 1.23 mmcable dia. 1.23 mm• 1865 / 1980 windings1865 / 1980 windings• 40% NiTi40% NiTi• RRR ~ 100RRR ~ 100

Linearity (B vs. I) better 0.4% up to 300 ALinearity (B vs. I) better 0.4% up to 300 ALinearity (B vs. I) better 0.4% up to 300 ALinearity (B vs. I) better 0.4% up to 300 A

BBTOTTOT deviates from expected deviates from expected

due to Steel support structuredue to Steel support structure!!! Needs to be re-measured at PSI !!!!!! Needs to be re-measured at PSI !!! “ “Acceptance Tests”Acceptance Tests”

BBTOTTOT deviates from expected deviates from expected

due to Steel support structuredue to Steel support structure!!! Needs to be re-measured at PSI !!!!!! Needs to be re-measured at PSI !!! “ “Acceptance Tests”Acceptance Tests”


BTS Preparations PSIBTS Preparations PSIBTS Preparations PSIBTS Preparations PSI

Preparations for BTS Installation in Preparations for BTS Installation in E5E5

• cryogenic lines for LHe & LNcryogenic lines for LHe & LN2 2 ready for connectionready for connection• valve chamber ready for mounting on BTSvalve chamber ready for mounting on BTS• power supply tested & readypower supply tested & ready

Preparations for BTS Installation in Preparations for BTS Installation in E5E5

• cryogenic lines for LHe & LNcryogenic lines for LHe & LN2 2 ready for connectionready for connection• valve chamber ready for mounting on BTSvalve chamber ready for mounting on BTS• power supply tested & readypower supply tested & ready

Valve ChamberValve Chamber

Couples BTS toCouples BTS toLHe transfer Line LHe transfer Line contains contains Joule-ThompsonJoule-ThompsonValves for controlValves for control

Valve ChamberValve Chamber

Couples BTS toCouples BTS toLHe transfer Line LHe transfer Line contains contains Joule-ThompsonJoule-ThompsonValves for controlValves for control

LHe Transfer LineLHe Transfer Line

Refrigerator unitRefrigerator unitAbove Above E5E5

LHe TransferLHe TransferLineLine

LHe lineLHe line


BTS arrival PSIBTS arrival PSIBTS arrival PSIBTS arrival PSI

BTS arrival PSIBTS arrival PSI *** 8th July ****** 8th July ***

Acceptance TestsAcceptance Tests

• assembly / survey assembly / survey • vacuum / leak tests vacuum / leak tests • cryogenic installation cryogenic installation • electrical installation electrical installation • cool-downcool-down• quench detection /quench detection / protection tests protection tests • Bfield measurements Bfield measurements

BTS arrival PSIBTS arrival PSI *** 8th July ****** 8th July ***

Acceptance TestsAcceptance Tests

• assembly / survey assembly / survey • vacuum / leak tests vacuum / leak tests • cryogenic installation cryogenic installation • electrical installation electrical installation • cool-downcool-down• quench detection /quench detection / protection tests protection tests • Bfield measurements Bfield measurements

“ “ On route PSI”On route PSI” ~ 6500 km~ 6500 kmNovosibirsk - PSINovosibirsk - PSI

“ “ On route On route E5”E5”

8th July 20058th July 20058th July 20058th July 2005 14th July 200514th July 2005 E5E5

14th July 200514th July 2005 E5E5

!!! Problems !!!!!! Problems !!!• welding joint tower / cryostatwelding joint tower / cryostat damaged in transportdamaged in transport Re-welded OKRe-welded OK• cryogenic connection valve-cryogenic connection valve- chamber / LHe transfer line chamber / LHe transfer line not compatible not compatible To workshopsTo workshops

Use dewar system LHeUse dewar system LHe

!!! Problems !!!!!! Problems !!!• welding joint tower / cryostatwelding joint tower / cryostat damaged in transportdamaged in transport Re-welded OKRe-welded OK• cryogenic connection valve-cryogenic connection valve- chamber / LHe transfer line chamber / LHe transfer line not compatible not compatible To workshopsTo workshops

Use dewar system LHeUse dewar system LHe

LNLN22

ValveValvechamberchamber

*** Dmitry Reports: 18th July *** Dmitry Reports: 18th July 11:00 coil superconducting11:00 coil superconducting20:00 *** 283A reached ***20:00 *** 283A reached *** (nominal ~ 200A(nominal ~ 200A))

*** Dmitry Reports: 18th July *** Dmitry Reports: 18th July 11:00 coil superconducting11:00 coil superconducting20:00 *** 283A reached ***20:00 *** 283A reached *** (nominal ~ 200A(nominal ~ 200A))


He-Bag & Target System He-Bag & Target System StatusStatusHe-Bag & Target System He-Bag & Target System StatusStatus


He-Bag / Target System - GeneralHe-Bag / Target System - GeneralHe-Bag / Target System - GeneralHe-Bag / Target System - General

(I) Desired Beam Characteristics(I) Desired Beam Characteristics

• transport maximum number transport maximum number µµ++ to the target to the target (vacuum / He, large (vacuum / He, large ΔΔPP))• maximize µmaximize µ++ stopping-rate in the target stopping-rate in the target (small (small ΔΔP, vacuum /He)P, vacuum /He)• minimize beam spot size & multiple scattering minimize beam spot size & multiple scattering (vacuum / He, degrader close to target)(vacuum / He, degrader close to target)• minimize background from decays or Bremsstrahlungminimize background from decays or Bremsstrahlung (degrader far from away, vacuum / He) (degrader far from away, vacuum / He)

(II) Desired(II) Desired Target RequirementsTarget Requirements

• depolarizing target depolarizing target (isotropic e(isotropic e++, non-metal), non-metal)• minimum target size minimum target size (low-Z)(low-Z)• minimize material traversed by decay eminimize material traversed by decay e+ + & & (slanted target)(slanted target)• minimize generation of annihilation photons minimize generation of annihilation photons (large X(large X00, low-Z e.g. CH2), low-Z e.g. CH2)

(I) Desired Beam Characteristics(I) Desired Beam Characteristics

• transport maximum number transport maximum number µµ++ to the target to the target (vacuum / He, large (vacuum / He, large ΔΔPP))• maximize µmaximize µ++ stopping-rate in the target stopping-rate in the target (small (small ΔΔP, vacuum /He)P, vacuum /He)• minimize beam spot size & multiple scattering minimize beam spot size & multiple scattering (vacuum / He, degrader close to target)(vacuum / He, degrader close to target)• minimize background from decays or Bremsstrahlungminimize background from decays or Bremsstrahlung (degrader far from away, vacuum / He) (degrader far from away, vacuum / He)

(II) Desired(II) Desired Target RequirementsTarget Requirements

• depolarizing target depolarizing target (isotropic e(isotropic e++, non-metal), non-metal)• minimum target size minimum target size (low-Z)(low-Z)• minimize material traversed by decay eminimize material traversed by decay e+ + & & (slanted target)(slanted target)• minimize generation of annihilation photons minimize generation of annihilation photons (large X(large X00, low-Z e.g. CH2), low-Z e.g. CH2)

Consequences:Consequences:• vacuum window interface to COBRAvacuum window interface to COBRA• He-atmosphere inside COBRAHe-atmosphere inside COBRA• slanted, non-metallic, low-Z, large Xslanted, non-metallic, low-Z, large X00 target target

Consequences:Consequences:• vacuum window interface to COBRAvacuum window interface to COBRA• He-atmosphere inside COBRAHe-atmosphere inside COBRA• slanted, non-metallic, low-Z, large Xslanted, non-metallic, low-Z, large X00 target target


COBRA-EnvironmentCOBRA-EnvironmentCOBRA-EnvironmentCOBRA-Environment

(III) COBRA Environment Requirements(III) COBRA Environment Requirements

• thin vacuum window at entrance COBRA thin vacuum window at entrance COBRA (190(190µ Mylar)µ Mylar)• safety measures against vacuum window rupture safety measures against vacuum window rupture (safety seals !!!)(safety seals !!!) • must maintain DC & TC dimensions & insertion conceptsmust maintain DC & TC dimensions & insertion concepts• stringent constant differential He-pressure between DCs & COBRA stringent constant differential He-pressure between DCs & COBRA (~few (~few µb)µb)• no He-leakage to TC PMs no He-leakage to TC PMs (N(N22-Bag)-Bag)• frequent / less frequent access to Downstream side for calibration frequent / less frequent access to Downstream side for calibration & monitoring purposes & monitoring purposes ( e.g. Cockroft-Walton, ( e.g. Cockroft-Walton, - - CEX)CEX)• possibility to exchange targets possibility to exchange targets ( LiF, LH( LiF, LH22, CH, CH2 2 etc.)etc.)

(III) COBRA Environment Requirements(III) COBRA Environment Requirements

• thin vacuum window at entrance COBRA thin vacuum window at entrance COBRA (190(190µ Mylar)µ Mylar)• safety measures against vacuum window rupture safety measures against vacuum window rupture (safety seals !!!)(safety seals !!!) • must maintain DC & TC dimensions & insertion conceptsmust maintain DC & TC dimensions & insertion concepts• stringent constant differential He-pressure between DCs & COBRA stringent constant differential He-pressure between DCs & COBRA (~few (~few µb)µb)• no He-leakage to TC PMs no He-leakage to TC PMs (N(N22-Bag)-Bag)• frequent / less frequent access to Downstream side for calibration frequent / less frequent access to Downstream side for calibration & monitoring purposes & monitoring purposes ( e.g. Cockroft-Walton, ( e.g. Cockroft-Walton, - - CEX)CEX)• possibility to exchange targets possibility to exchange targets ( LiF, LH( LiF, LH22, CH, CH2 2 etc.)etc.)

COBRACOBRA

Target SystemTarget System

Target InsertionTarget Insertion tubetube

EndEndCapCapUSUS

EndEndCap Cap DSDS

VacuumVacuumwindowwindow

ConsequencesConsequences1.1. Thin beam line Vacuum Window Thin beam line Vacuum Window 2.2. COBRA End-Cap Flanges + HE-seals COBRA End-Cap Flanges + HE-seals (US,DS)(US,DS)3.3. Target Insertion Tube & supportTarget Insertion Tube & support system (separate He-environment) system (separate He-environment) (TISS)(TISS)4.4. Target System Target System (TS)(TS)

*** PSI staged Engineering Design Project*** PSI staged Engineering Design Project started – design & construction ***started – design & construction *** (i)US-flange, (ii) DS-flange, (iii) TISS, (iv) TS(i)US-flange, (ii) DS-flange, (iii) TISS, (iv) TS – – design & Construction ready – Feb. 2006design & Construction ready – Feb. 2006

ConsequencesConsequences1.1. Thin beam line Vacuum Window Thin beam line Vacuum Window 2.2. COBRA End-Cap Flanges + HE-seals COBRA End-Cap Flanges + HE-seals (US,DS)(US,DS)3.3. Target Insertion Tube & supportTarget Insertion Tube & support system (separate He-environment) system (separate He-environment) (TISS)(TISS)4.4. Target System Target System (TS)(TS)

*** PSI staged Engineering Design Project*** PSI staged Engineering Design Project started – design & construction ***started – design & construction *** (i)US-flange, (ii) DS-flange, (iii) TISS, (iv) TS(i)US-flange, (ii) DS-flange, (iii) TISS, (iv) TS – – design & Construction ready – Feb. 2006design & Construction ready – Feb. 2006


End-Cap Flanges & He-Bag sealsEnd-Cap Flanges & He-Bag sealsEnd-Cap Flanges & He-Bag sealsEnd-Cap Flanges & He-Bag seals

COBRACOBRAcryostatcryostat

USUS End-CapEnd-Cap FlangeFlange

NN22-Bag-Bag BeamBeam pipepipe

Engineering Design Concept Upstream End-CapEngineering Design Concept Upstream End-CapEngineering Design Concept Upstream End-CapEngineering Design Concept Upstream End-Cap

BeamBeam

COBRACOBRA DesignDesignAllows open Allows open access to TCs +access to TCs + withdrawalwithdrawalwithout affectingwithout affectingHe-environmentHe-environment

MountingMounting1.1. NN22-Bag-Bag

2.2. TC-railsTC-rails3.3. End-Cap +End-Cap + He-BagHe-Bag4.4. TCsTCs5.5. Beam pipe Beam pipe with BTSwith BTS6.6. Couple He-Couple He- Bag rings to Bag rings to vac. windowvac. window

DesignDesignAllows open Allows open access to TCs +access to TCs + withdrawalwithdrawalwithout affectingwithout affectingHe-environmentHe-environment

MountingMounting1.1. NN22-Bag-Bag

2.2. TC-railsTC-rails3.3. End-Cap +End-Cap + He-BagHe-Bag4.4. TCsTCs5.5. Beam pipe Beam pipe with BTSwith BTS6.6. Couple He-Couple He- Bag rings to Bag rings to vac. windowvac. window

He-BagHe-Bagcompositioncomposition

SandwichSandwichCHCH22/EVAL/CH/EVAL/CH22

He-BagHe-Bagcompositioncomposition

SandwichSandwichCHCH22/EVAL/CH/EVAL/CH22

InsertionInsertion TCsTCs

He-BagHe-Bag

RuptureRupture SealsSeals

He-BagHe-Baginnerinnersealingsealingringsrings


Target Optics - momentumTarget Optics - momentumTarget Optics - momentumTarget Optics - momentum

Goal:Goal: maximize stop-density (min. target size)maximize stop-density (min. target size)

Question:Question: optimum beam momentum?optimum beam momentum?Answer:Answer: 28.2 MeV/c28.2 MeV/c

Goal:Goal: maximize stop-density (min. target size)maximize stop-density (min. target size)

Question:Question: optimum beam momentum?optimum beam momentum?Answer:Answer: 28.2 MeV/c28.2 MeV/c

Momentum-Momentum-Spectrum: Spectrum: Data:Data: whole Beam Line optimized for whole Beam Line optimized for each data point + 2-D Scan for each data point + 2-D Scan for each point !!!each point !!!Theory:Theory: -Kinematic Edge (29.79 -Kinematic Edge (29.79 MeV/c)MeV/c)Theoretical func. PTheoretical func. P3.53.5 folded folded with Gaussian with Gaussian ΔΔP/P + Const. P/P + Const. Cloud Cloud µµ++ contribution contribution Fitted Fitted to data to data

2/dof = 0.94Pcent = (28.16 0.02) MeV/cP/P = (7.7 0.3) % FWHM

Pbeam = (28.2 0.9) MeV/c

2/dof = 0.94Pcent = (28.16 0.02) MeV/cP/P = (7.7 0.3) % FWHM

Pbeam = (28.2 0.9) MeV/c

Muon Range-Momentum Dependence CH2

R= 0.0108 P3.4752

rho2 = 1

0.0

200.0

400.0

600.0

800.0

1000.0

1200.0

1400.0

25.5 26.0 26.5 27.0 27.5 28.0 28.5

M uon M omentum [M eV/]

Mu

on

Ran

ge

in C

H2

[mic

ron

s]

Range R [microns]SigR [microns]

Muon Stopping Rate vs. Momentum (400 micron Tg)

0.700

0.750

0.800

0.850

0.900

0.950

1.000

1.050

25.50 26.00 26.50 27.00 27.50 28.00 28.50

Muon Momentum MeV/c

No

rm.

Rel

ativ

e M

uo

n S

top

pin

g R

ate

Muon Stopping Fraction

P**3.5 Rate Dep.

Rel. Muon Stopping Rate

Power (Rel. MuonStopping Rate)Power (Muon StoppingFraction)

++ range vs. P range vs. P(fixed (fixed P/P~ 7.7% FWHM)P/P~ 7.7% FWHM)

• straggling ~11 %straggling ~11 %• characteristic Pcharacteristic P3.53.5

++ range vs. P range vs. P(fixed (fixed P/P~ 7.7% FWHM)P/P~ 7.7% FWHM)

• straggling ~11 %straggling ~11 %• characteristic Pcharacteristic P3.53.5

++ Stopping Rate vs. P Stopping Rate vs. P(fixed (fixed P/P~ 7.7% FWHMP/P~ 7.7% FWHMfixed 400fixed 400 CH CH22 target) target)

• as p > relative stop rate <as p > relative stop rate <

• as p > beam rate > as p > beam rate >

Optimal Stop RateOptimal Stop Rate at P~28.2 MeV/cat P~28.2 MeV/c

++ Stopping Rate vs. P Stopping Rate vs. P(fixed (fixed P/P~ 7.7% FWHMP/P~ 7.7% FWHMfixed 400fixed 400 CH CH22 target) target)

• as p > relative stop rate <as p > relative stop rate <

• as p > beam rate > as p > beam rate >

Optimal Stop RateOptimal Stop Rate at P~28.2 MeV/cat P~28.2 MeV/c

straggling ~ 11%straggling ~ 11%straggling ~ 11%straggling ~ 11%

PP3.53.5PP3.53.5

Rel. Rel. stops stopsRel. Rel. stops stops

PP3.53.5PP3.53.5

Norm. Norm. -stops-stopsNorm. Norm. -stops-stops


Target Optics - degraderTarget Optics - degraderTarget Optics - degraderTarget Optics - degrader

Many solutions studied – 2 main categoriesMany solutions studied – 2 main categoriesMany solutions studied – 2 main categoriesMany solutions studied – 2 main categoriesSingle NodeSingle Node

SNMSNM

Single NodeSingle NodeSNMSNM

Double NodeDouble NodeDNMDNM

Double NodeDouble NodeDNMDNM

BTSBTSDMNDMNDMNDMN

Beam envelope (cm)Beam envelope (cm) Beam envelope (cm)Beam envelope (cm)

Beam divergence (mradBeam divergence (mrad)) Beam divergence (mradBeam divergence (mrad))

Momentum Profile (MeV/c)Momentum Profile (MeV/c)Momentum Profile (MeV/c)Momentum Profile (MeV/c)

BTSBTS COBRACOBRA

(1) DNM – Solution(1) DNM – Solution (190(190 Mylar Window) Mylar Window)

• BTS / COBRA unlike BTS / COBRA unlike polaritiespolarities• BBBTSBTS = -3.55 kG = -3.55 kG

• degrader 480degrader 480 CH CH2 2 at at

centre BTScentre BTS beam beam ~ 12.5 mm ~ 12.5 mm

(1) DNM – Solution(1) DNM – Solution (190(190 Mylar Window) Mylar Window)

• BTS / COBRA unlike BTS / COBRA unlike polaritiespolarities• BBBTSBTS = -3.55 kG = -3.55 kG

• degrader 480degrader 480 CH CH2 2 at at

centre BTScentre BTS beam beam ~ 12.5 mm ~ 12.5 mm

P ~ 4.2 MeV/cP ~ 4.2 MeV/c

P ~ 2 MeV/cP ~ 2 MeV/c

P ~ 4.5 MeV/cP ~ 4.5 MeV/c

Transmission Transmission Efficiency (%)Efficiency (%)Transmission Transmission Efficiency (%)Efficiency (%)

TTBTS BTS ~ 98%~ 98% TTBTS+COBRABTS+COBRA~ 88%~ 88%

3% decays3% decays9% straggling9% straggling

TransmissionTransmissionEfficiencyEfficiency

• TTBTS+DegBTS+Deg = 98% = 98%• TTBTS+deg+COBRABTS+deg+COBRA = 88% = 88%• TTSep+TII+ClliSep+TII+Clli = 86.5% = 86.5%

Expected Stopping RateExpected Stopping Rate

RR = 9.6 = 9.6·10·1077 ++/s /s

at 1.8mA 4cm Tgat 1.8mA 4cm Tg

(1.7·10(1.7·1088 ++/s at 1.8mA 6cm Tg)/s at 1.8mA 6cm Tg)

BTSBTSCOBRACOBRA


Target Optics – degrader cont.Target Optics – degrader cont.Target Optics – degrader cont.Target Optics – degrader cont.

(2) SNM Solutions ( no degrader in BTS)(2) SNM Solutions ( no degrader in BTS) (125(125 Mylar Window) Mylar Window)

• either combine Degrader + Target (asymmetric stop distribution)either combine Degrader + Target (asymmetric stop distribution)

• or move degrader slightly upstream of target (e.g. use as end-wall of target insertion tube)or move degrader slightly upstream of target (e.g. use as end-wall of target insertion tube)

(2) SNM Solutions ( no degrader in BTS)(2) SNM Solutions ( no degrader in BTS) (125(125 Mylar Window) Mylar Window)

• either combine Degrader + Target (asymmetric stop distribution)either combine Degrader + Target (asymmetric stop distribution)

• or move degrader slightly upstream of target (e.g. use as end-wall of target insertion tube)or move degrader slightly upstream of target (e.g. use as end-wall of target insertion tube)

targettargettargettargetee++

beambeam

degraderdegraderdegraderdegrader

ee++

targettargettargettargetbeambeam

SNMSNM

SNMSNM

DNMDNMDNMDNM

unlikeunlikepolaritypolarityunlikeunlikepolaritypolarity like polaritylike polarity like polaritylike polarity

COBRA Spot size vs BCOBRA Spot size vs BBTSBTSCOBRA Spot size vs BCOBRA Spot size vs BBTSBTS

Combined Tg + DegCombined Tg + DegCombined Tg + DegCombined Tg + Degupstream Deg. 15 cmupstream Deg. 15 cmupstream Deg. 15 cmupstream Deg. 15 cm

Conclusions SNM Conclusions SNM (no BTS degrader)(no BTS degrader)

• Combined SolCombined Solnn:: gives gives ~ 10 mm for 125 ~ 10 mm for 125 Mylar Window Mylar Window with 190 with 190 Mylar Mylar ~ 11.5 mm ~ 11.5 mm• no straggling lossno straggling loss only 3% decay loss only 3% decay loss

Expected Rate RExpected Rate R ~ 1.06 ~ 1.06·10·1088 ++/s at 1.8mA 4 cm Tg./s at 1.8mA 4 cm Tg. • BUT annihilation radiation potential worse - BUT annihilation radiation potential worse - needs to be simulatedneeds to be simulated

• Upstream SolUpstream Solnn:: gives similar results to gives similar results to DNM DNM ~ 12.5 mm ~ 12.5 mm• annihilation radiation potential worse - annihilation radiation potential worse - needs to be simulatedneeds to be simulated

Conclusions SNM Conclusions SNM (no BTS degrader)(no BTS degrader)

• Combined SolCombined Solnn:: gives gives ~ 10 mm for 125 ~ 10 mm for 125 Mylar Window Mylar Window with 190 with 190 Mylar Mylar ~ 11.5 mm ~ 11.5 mm• no straggling lossno straggling loss only 3% decay loss only 3% decay loss

Expected Rate RExpected Rate R ~ 1.06 ~ 1.06·10·1088 ++/s at 1.8mA 4 cm Tg./s at 1.8mA 4 cm Tg. • BUT annihilation radiation potential worse - BUT annihilation radiation potential worse - needs to be simulatedneeds to be simulated

• Upstream SolUpstream Solnn:: gives similar results to gives similar results to DNM DNM ~ 12.5 mm ~ 12.5 mm• annihilation radiation potential worse - annihilation radiation potential worse - needs to be simulatedneeds to be simulated


Target & Insertion TubeTarget & Insertion TubeTarget & Insertion TubeTarget & Insertion Tube

Target Geometry Target Geometry ( for beam ( for beam = 10mm) = 10mm)

LLPROJ PROJ = 150.4 mm, = 150.4 mm, = 21.8 = 21.8°°, a = 60.3 mm, , a = 60.3 mm, LLTRUE TRUE = 161.9 mm= 161.9 mm

material: CHmaterial: CH22 + Rohacell / Mylar + Rohacell / Mylar

Slanted Target must be thicker – multiple scattering lossSlanted Target must be thicker – multiple scattering losson downstream-side !!!on downstream-side !!!

Target Simulation underway:Target Simulation underway:

• check of optimum angle check of optimum angle • dependence on target thickness (multiple scattering,dependence on target thickness (multiple scattering, background, acceptance, timing, resolution)background, acceptance, timing, resolution)• material considerationsmaterial considerations• decay particle hit distributions on end-cap materials &decay particle hit distributions on end-cap materials & associated background acceptance associated background acceptance

Target Geometry Target Geometry ( for beam ( for beam = 10mm) = 10mm)

LLPROJ PROJ = 150.4 mm, = 150.4 mm, = 21.8 = 21.8°°, a = 60.3 mm, , a = 60.3 mm, LLTRUE TRUE = 161.9 mm= 161.9 mm

material: CHmaterial: CH22 + Rohacell / Mylar + Rohacell / Mylar

Slanted Target must be thicker – multiple scattering lossSlanted Target must be thicker – multiple scattering losson downstream-side !!!on downstream-side !!!

Target Simulation underway:Target Simulation underway:

• check of optimum angle check of optimum angle • dependence on target thickness (multiple scattering,dependence on target thickness (multiple scattering, background, acceptance, timing, resolution)background, acceptance, timing, resolution)• material considerationsmaterial considerations• decay particle hit distributions on end-cap materials &decay particle hit distributions on end-cap materials & associated background acceptance associated background acceptance

LLPROJPROJLLPROJPROJ

LLTRUETRUELLTRUETRUE


Target & Insertion Tube + surveyTarget & Insertion Tube + surveyTarget & Insertion Tube + surveyTarget & Insertion Tube + survey

Target Insertion Tube & Support System (TISS)Target Insertion Tube & Support System (TISS)

Material:Material:• Rohacell (PMI) closed cell foam, maybe + EVAL foil? Rohacell (PMI) closed cell foam, maybe + EVAL foil? wall thickness probably 2 mm Rohacell 31wall thickness probably 2 mm Rohacell 31• length ~ 1500 mmlength ~ 1500 mm• dia. ~150 mmdia. ~150 mm• Weight ~ 51 gWeight ~ 51 g• simulations concerning background from simulations concerning background from ee+ + interactions in TISS underwayinteractions in TISS underway

Target Insertion Tube & Support System (TISS)Target Insertion Tube & Support System (TISS)

Material:Material:• Rohacell (PMI) closed cell foam, maybe + EVAL foil? Rohacell (PMI) closed cell foam, maybe + EVAL foil? wall thickness probably 2 mm Rohacell 31wall thickness probably 2 mm Rohacell 31• length ~ 1500 mmlength ~ 1500 mm• dia. ~150 mmdia. ~150 mm• Weight ~ 51 gWeight ~ 51 g• simulations concerning background from simulations concerning background from ee+ + interactions in TISS underwayinteractions in TISS underway

Target Insertion TubeTarget Insertion Tube

FlangeFlangelateral +lateral +verticalverticalmove-move-mentment

Survey aspects:Survey aspects:

• target plane determined outside wrt. survey markerstarget plane determined outside wrt. survey markers on rohacell support rings (laser tracker)on rohacell support rings (laser tracker)• possible temporary thin cross-wires on support ringspossible temporary thin cross-wires on support rings for axial + radial alignment (break afterwards)for axial + radial alignment (break afterwards)• radial adjustment made with TISS end-flangeradial adjustment made with TISS end-flange• axial position set by TISS (self-positioning)axial position set by TISS (self-positioning)

Survey aspects:Survey aspects:

• target plane determined outside wrt. survey markerstarget plane determined outside wrt. survey markers on rohacell support rings (laser tracker)on rohacell support rings (laser tracker)• possible temporary thin cross-wires on support ringspossible temporary thin cross-wires on support rings for axial + radial alignment (break afterwards)for axial + radial alignment (break afterwards)• radial adjustment made with TISS end-flangeradial adjustment made with TISS end-flange• axial position set by TISS (self-positioning)axial position set by TISS (self-positioning)

-target-targetsystemsystem


Schedule 2005Schedule 2005Schedule 2005Schedule 2005

Changes 2005: Changes 2005: (compared to previous schedule)(compared to previous schedule)• Separator schedule + 8 weeksSeparator schedule + 8 weeks• BTS Schedule + 7 weeksBTS Schedule + 7 weeks• COBRA end-cap + target design + manufacture extendedCOBRA end-cap + target design + manufacture extended

Changes 2005: Changes 2005: (compared to previous schedule)(compared to previous schedule)• Separator schedule + 8 weeksSeparator schedule + 8 weeks• BTS Schedule + 7 weeksBTS Schedule + 7 weeks• COBRA end-cap + target design + manufacture extendedCOBRA end-cap + target design + manufacture extended

Critical PathCritical Path• Commissioning Part 1 too short for BTS/COBRA Commissioning Part 1 too short for BTS/COBRA phase space measurements phase space measurements Dec. Part 2 Dec. Part 2• final Target measurements final Target measurements first beam 2006 first beam 2006

Critical PathCritical Path• Commissioning Part 1 too short for BTS/COBRA Commissioning Part 1 too short for BTS/COBRA phase space measurements phase space measurements Dec. Part 2 Dec. Part 2• final Target measurements final Target measurements first beam 2006 first beam 2006


Summary + Critical PathSummary + Critical PathSummary + Critical PathSummary + Critical Path

Summary:Summary:

• beam transport system up to COBRA beam transport system up to COBRA defineddefined• COBRA + Platform COBRA + Platform surveyed into positionsurveyed into position• All beam transport elements All beam transport elements now manufacturednow manufactured• MEG Separator MEG Separator being conditionedbeing conditioned• BTS successfully BTS successfully tested in Novosibirsktested in Novosibirsk & & delivered PSI (8th July)delivered PSI (8th July)• BTS BTS reached current of 283Areached current of 283A during commissioning during commissioning at PSI (18th July)at PSI (18th July)• All cryogenic lines All cryogenic lines installedinstalled to zone to zone• all vacuum system all vacuum system available available • engineering project for COBRA end-caps + target Insertion & support system engineering project for COBRA end-caps + target Insertion & support system underwayunderway manufacture to be manufacture to be completed Feb. 2006completed Feb. 2006

Summary:Summary:

• beam transport system up to COBRA beam transport system up to COBRA defineddefined• COBRA + Platform COBRA + Platform surveyed into positionsurveyed into position• All beam transport elements All beam transport elements now manufacturednow manufactured• MEG Separator MEG Separator being conditionedbeing conditioned• BTS successfully BTS successfully tested in Novosibirsktested in Novosibirsk & & delivered PSI (8th July)delivered PSI (8th July)• BTS BTS reached current of 283Areached current of 283A during commissioning during commissioning at PSI (18th July)at PSI (18th July)• All cryogenic lines All cryogenic lines installedinstalled to zone to zone• all vacuum system all vacuum system available available • engineering project for COBRA end-caps + target Insertion & support system engineering project for COBRA end-caps + target Insertion & support system underwayunderway manufacture to be manufacture to be completed Feb. 2006completed Feb. 2006

Critical Points:Critical Points:

• COBRA phase space measurement delayed until Dec. 2005 (delays Separator + BTS)COBRA phase space measurement delayed until Dec. 2005 (delays Separator + BTS)• Final measurements with target delayed until first beam 2006 Final measurements with target delayed until first beam 2006

Critical Points:Critical Points:

• COBRA phase space measurement delayed until Dec. 2005 (delays Separator + BTS)COBRA phase space measurement delayed until Dec. 2005 (delays Separator + BTS)• Final measurements with target delayed until first beam 2006 Final measurements with target delayed until first beam 2006


-Beam Results (re-cap) -Beam Results (re-cap) -Beam Results (re-cap) -Beam Results (re-cap)

FirstFirst -- Beam Studies with MEG Beam: Beam Studies with MEG Beam:

for calibration purposes in the experiment for calibration purposes in the experiment

--pp→→00n, n, --pp→→nn

55 55 → 83 MeV → 83 MeV s and 129 MeV s and 129 MeV ss

Data taken from:Data taken from:

• P-spectrum measurements 25-33 MeV/cP-spectrum measurements 25-33 MeV/c

s detected above 30 MeV/c (pulse-ht. + RF tof)s detected above 30 MeV/c (pulse-ht. + RF tof)• dedicated dedicated -- runs at 56 MeV/c & 103 MeV/c runs at 56 MeV/c & 103 MeV/c 56 MeV/c interesting since max. momentum 56 MeV/c interesting since max. momentum that can be transported to COBRA with that can be transported to COBRA with good optics SNM in BTSgood optics SNM in BTS• dedicated CEX run at 112 MeV/cdedicated CEX run at 112 MeV/c

FirstFirst -- Beam Studies with MEG Beam: Beam Studies with MEG Beam:

for calibration purposes in the experiment for calibration purposes in the experiment

--pp→→00n, n, --pp→→nn

55 55 → 83 MeV → 83 MeV s and 129 MeV s and 129 MeV ss

Data taken from:Data taken from:

• P-spectrum measurements 25-33 MeV/cP-spectrum measurements 25-33 MeV/c

s detected above 30 MeV/c (pulse-ht. + RF tof)s detected above 30 MeV/c (pulse-ht. + RF tof)• dedicated dedicated -- runs at 56 MeV/c & 103 MeV/c runs at 56 MeV/c & 103 MeV/c 56 MeV/c interesting since max. momentum 56 MeV/c interesting since max. momentum that can be transported to COBRA with that can be transported to COBRA with good optics SNM in BTSgood optics SNM in BTS• dedicated CEX run at 112 MeV/cdedicated CEX run at 112 MeV/c

Provisional ResultsProvisional Results -- Integral Spot Rates MHzIntegral Spot Rates MHzfor 1,8mA Proton Current & 4cm Target Efor 1,8mA Proton Current & 4cm Target E

Normalized to Momentum Slit Settings:Normalized to Momentum Slit Settings: FS41L/R 250/280 FS43L/R 240/220FS41L/R 250/280 FS43L/R 240/220

56 MeV/c 56 MeV/c RR = 7.6 = 7.6 ·10·1066 --/s/s slits open slits open

RR = 7.2 = 7.2 ·10·1055 --/s slits70/70/s slits70/7056 MeV/c 56 MeV/c RR = 7.6 = 7.6 ·10·1066 --/s/s slits open slits open

RR = 7.2 = 7.2 ·10·1055 --/s slits70/70/s slits70/70

ee--

μμ--

--

Documents

P.-R Kettle MEG Review July 2005 1 Beam Transport & Target Systems BTS Success Novosibirsk 24/5/2005 18:15 300 A 300 A