MICE: Constraints on the solenoids

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Alain Blondel MICE: Constraints on the solenoids d Homogeneity: 10 -2 or 10 -3 ? l be dictated by the detector requirements. be more demanding (uses the field actively as guide for drift) to be made! ons: we decided in Chicago in February that spectrometer field region should be 100 cm long and 30 cm di ore should be 40 cm 4. WHICH CONFIGURATIONS? Personal thoughts……..for discussion: tching: hould be magnetically transparent. equires a matched magnetic system for a certain number of configurat ilability of the corresponding KNOBS vable elements

description

MICE: Constraints on the solenoids. Dimensions: we decided in Chicago in February that the useful spectrometer field region should be 100 cm long and 30 cm diameter. the inner bore should be 40 cm. Field Homogeneity: 10 -2 or 10 -3 ? this will be dictated by the detector requirements. - PowerPoint PPT Presentation

Transcript of MICE: Constraints on the solenoids

Page 1: MICE:  Constraints on the solenoids

Alain Blondel

MICE: Constraints on the solenoids

2. Field Homogeneity: 10-2 or 10-3 ?this will be dictated by the detector requirements. TPG will be more demanding (uses the field actively as guide for drift)=> STUDY to be made!

1. Dimensions: we decided in Chicago in February that

the useful spectrometer field region should be 100 cm long and 30 cm diameter. the inner bore should be 40 cm

4. WHICH CONFIGURATIONS?Personal thoughts……..for discussion:

3. Matching: MICE should be magnetically transparent. This requires a matched magnetic system for a certain number of configurations availability of the corresponding KNOBS Movable elements

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Alain Blondel

T.O.F. IIIT.O.F. IIIPrecise timingPrecise timing

Electron IDElectron IDEliminate muons that decay Eliminate muons that decay

Tracking devices: Tracking devices: He filled TPC-GEM (similar to TSLA R&D)He filled TPC-GEM (similar to TSLA R&D)and/or sci-fiand/or sci-fiMeasurement of momentum, angles and positionMeasurement of momentum, angles and position

T.O.F. I & IIT.O.F. I & IIPion /muon Pion /muon IDIDprecise precise timingtiming

10% cooling of 200 MeV muons requires ~ 20 MV of RF single particle measurements =>

measurement precision can be as good as out/ in ) = 10-3

201 MHz RF cavities

Liquid H2 absorbersor LiH ?

SC Solenoids;Spectrometer, focus pair, compensation coil

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STEP I: we get the muon beam

In this first phase we define the beam tunings, composition, settings for both mu+ and mu- as a function of momentum.

needed: beam (!)

TOF, trigger

some DAQ two SCI FI arrays or beam chambers

PID

10 m

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Alain Blondel

In this step we 1. turn on and map the first solenoid 2. study the acceptance

and the required thickness of the diffusers 3. debug the Tracker 4. verify the matching of TPG with Sci-fi or beam chamber 5. debug track identification devices 6. (MEASURE BEAM EMITTANCE IN SOLENOID!)

Step II: the first solenoid arrives, the tracker arrives a few weeks later.

needed:solenoid and all servicesmagnetic measurement systemtracking devices

+ -and

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Step III: TWO spectrometers

At this step we:-- Turn on and map the second solenoid -- Debug Spectrometer # 2-- Measure inout and the ratio-- Field reversal is important for E ^ B effects

THIS IS A VERY IMPORTANT STEP : THESE RESULTS WILL BE PART OF THE FINAL ONES

(Systematics on inout )

+ +

and --

do we need + - ?

-- can insert a number of materials to measure e.g.

dE/dx vs scattering angle correlation

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Step III- B: TWO spectrometers

-- can insert a number of materials to measure e.g. dE/dx vs scattering angle correlation

At this point we might want to bring in an absorber and measure its properties in this simpler configuration

++

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Alain Blondel

Step IV: TWO spectrometers and the LH2 absorber

At this step we:-- Turn on and map the flip pair-- Match the system-- Measure inout and the ratio -- for full AND empty absorber. -- for ++ AND +- configuration

-+

or

+ +

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Alain Blondel

Step V: first cooling cell

At this step we:-- Turn on and map the flip pair-- Match the system-- Measure inout and the ratio -- for full AND empty absorber. -- for ++ AND +- configuration

+

or

+

+ +

with flips

without flips

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Step VI: low beta study

See; Palmer – Fernow Note – or talk at the October 2001 Workshop at CERN. Limit is: current X 2 in flip coils and zero in coupling coil.

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Step VI: low beta study

+ + with flips

this has to be completely re-matched…. and re-mapped! Quite an operation…

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Other momenta?

MICE could certainly map the acceptance as a function of beam momentum for a given magnetic setting. Off-nominal-momentum performance may be sub-optimal (?). Should we try MICE matched for lower/higher momentum as well? more/less cooling!

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Step VII The full two-cell MICEibid. sensitivity will be better since volts will be higher.

can try various settings of polarities and absorbers (full / empty)and of absorber thicknesses (to match available RF or beam momentum)

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Preliminary conclusions

for discussion

1. It will be necessary to have enough knobs to vary the magnetic configuration to adapt to the various avatars of MICE

2. The various components of the magnetic channel will have to move along the experiment

3. There will be a lot of magnetic measurements to do!

(I must have been a mice (sorry, mouse) in one of my previous lives)