interim report on manx after mice

MANX interim CM23 1January 2009

INTERIM REPORT on MANX after MICE

Preamble

Several presentations related to the uses of the MICE infrastructure after MICE PHASE II were made at CM22.

The MICE executive board “concluded that it would be god (sic) if a smaller group of MICE physicists would take the time to go through these various proposals (by any means they see fit1) and answer specific questions which are within our competence as MICE and produce a short report ”.

The question “which is the most relevant R&D program after MICE’’ was excluded as not being within MICE competence.

1 Waterboarding was excluded


Scope

The questions suggested by the EB were:

1. Space-consistency in the MICE hall2. Scope and adequacy of proposals in view of existing

1. MICE instrumentation, and 2. Infrastructure

3. Consistency of time scales4. Comment on resources available from MANX and MICE5. Good use of MICE infrastructure resources

Committee

John Cobb (chair)Chris RogersMalcolm EllisYoshi Kuno

keeping the MICE Spokesman informed


After consulting the MICE spokesman it was decided that MANX was the most developed current proposal and that the committee should concentrate principally on MANX.

Nevertheless there are other possible experiments which could use some or all of the MICE infrastructure, and these should be considered similarly in the near to medium term.

Initial information about MANX was obtained from the latest MANX proposal [1], supplemented by specific questions to the MANX spokesman (R. Johnson).

[1] http://www.muonsinc.com/tiki-download_wiki_attachment.php?attId=305&page=Papers%20and%20Reports


BRIEF MANX OVERVIEW

3 m long He-filled Helical Cooling Channel 6D cooling

• Two possible configurations– ‘With Matching’

• Requires extra matching sections– ‘Off-axis’

• Inject & extract beam at an angle


MANX CONDITIONS & INSTRUMENTATION• From MANX proposal:

– 350 MeV/c muons in 150 – 200 MeV/c out– Longitudinal momentum measurements by Hi-res TOFs

• Up- & Down-stream• ~4pSec resolution using MCP PMTs

– Being developed– HCC interspersed with fibre tracker planes

• Expect factor ~2.5 (6-D) cooling in 3m HCC– Starting from 40mm transverse emittance & 8m longitudinal

• >> Largest MICE emittance of ~10mm– What is performance for ‘standard’ MICE beams?

• Including internal fibre planes– What resolutions are required?


OFF-AXIS MANX

• Smaller experiment – no matching sections– More money for cooling rather than matching

• But 50% losses into downstream spectrometer– MANX also considering 0.5m matching sections

• One end close to iron shield wall– Space for services close to wall?– Possible large error fields?

• Magnetics & Forces– Transfer of non-axial magnetic/quench forces – Torques on Spectrometer coils

• Not designed for these– Probably ‘Show Stoppers’ & did not consider OAM further

Presumably requiresN periods to be all in one plane (?)


SPACE CONSISTENCY – MATCHED MANXHCC cryostat No detailed dimensions available

HCC is 3m x ~0.5m radiusShould fit – but service turrets etc ??

HCC + Matching Longer overallPossibly need to extend false floor a few m

CryogenicsCryo. system not specified (tankers?)‘Considering using left-over cable from SSC for HCC; might prohibit cryocoolers’

Estimate ~2,500 litres of LHe in HCC

Space/cost for refrigerator ?

If LHe shipped in, who pays ?

TOF counters (Hi-res)Additional space downstream~1m for dp/p = 1%

Beam expands on leaving spectrometer large area TOFs ~1.2m x 1.2m (3 sigma, 5mm emittance)

Implications for size of downstream PID Mucal (EMR) etc.


SCOPE & ADEQUACY of INSTRUMENTATIONResolutions required ?

TransverseWhat is MANX criterion for (deps)/eps?

What is expected performance withstandard MICE beams of 3, 6, 10mm?(Esp.with internal HCC tracker planes.)

10mm is ~maximum beam emittance

Longitudinal

Proposal says dp/p of 1% for pl

New 5pSec TOFs for longitudinalmomentum measurement

Estimate 2D cooling for 350 150 MeV/c

Equilibrium emittance ~ 2.2mm10mm 5.5mm = 45% 3mm 2.5mm = 16%MICE spectrometers probably morethan adequate for transverse planes

What does ‘longitudinal’ mean if no RF?

Would like to understand goals better


SCOPE & ADEQUACY of INSTRUMENTATION - 2TOFs

Upstream PIDMANX considering newCerenkovs

Downstream PIDMANX considering newDownstream PID

Downstream momentum

MICE upstream TOFs with 8m give dp/p of~1% @ 200 MeV/c~3% @ 350 MeV/c+ ~3MeV/c straggling in TOFsDegraded by diffuser (15mm Pb) – how much ?Estimate additional ~3 MeV/c

Expect worse pi/mu ratio @ 350 MeV/cMICE Cerenkovs designed for <= 240 MeV/c

Is downstream PID adequate for higher pi/mu ratio? (don’t know; really for mu / e anyway)

Hi-res TOFs ~1m extra space downstream of spectrometer Downstream PID detectors must be larger

Gas-filled TPCs in place of fibre tracker? (save some space)


MICE INFRASTRUCTURE – BEAM

Operation at 350 MeV/c Somewhat unknown territory

D1 can give 480 MeV/cHave run D2 up to 450 MeV/c for protons

Mu’s from forward pi decays (?)Worse pi/mu ratio, probably (?)Useful muon rate?

Probably possible

‘can be studied by MICE within the next few months after the decay solenoid works’(depends on other MICE priorities)


INFRASTRUCTURE – SPECTROMETERS

Matching

Beta HCC matching section~33cm

Upstream field ~6T

May have to increase Match Coil currentsEstimate ~ 350/200 = 1.75

Probably cannot be done with current designwhich is ‘good enough’ for MICE

Needs evaluation

Possible show stopper

Engineering Margins of match coils – little in hand

Forces – go like B^2How to transfer?

Could matching be done with extra match coils(as well as MANX matching sections)? even longer channel; not nice


INFRASTRUCTURE – 2

Shielding / Stray fieldsHCC is not symmetric (6T 3.5T) Is shielding adequate for 6T?

Larger fields in HallEffect on other equipment?Asymmetric error fields?Effect on performance (if any)?

Needs evaluation

LH2MANX could use it:

‘Would be better experiment butengineering issues’ (RJ)

HCC is 3m long x 50cm radius ~2,500 litres~ 40 x MICE LH2 volume

Unlikely MICE LH2 systems could cope

Would need different systems for LHe


INFRASTRUCTURE – 3 RF systemsNot required; no plan to use them

Could be removed to make spaceUse for ??

DAQ Expand for HCC tracker planes & Hi-res TOFsSpace in MCR / racks?

SoftwareAssumed that MICE software will besufficient

Yes, but…

(a) Needs adapting for specific MANX detectors

(b) Need to use something nowto demonstrate goals & feedback toengineering

Upstream part of Hall / Beam Probably no change

D1 can go to 480 MeV/cD2 can go to 450 MeV/c


TIMESCALES

Plan to follow MICE in 2013

‘Mount within ~1 year of MICEfinishing whilst expertise available’

HCC would take ~4 years to engineer, design & build

2013 if started now

1 year to install

No engineering design for HCC;No simulation in MICE context

Need to demonstrate engineering,develop Hi-res TOFs, … within about twoyears.

Seems challenging – despite savings ininfrastructure & detectors – cf time fromMICE LOI / Proposal to now ~8 years

Requires engineering resources soon andsubstantial interaction with MICE experts (ifavailable)

Timescale seems rather optimistic


EFFORT NEEDEDSimulate MANX

Software

Engineer & build

Demount MICE

Mount MANX

Some assumptions that MICE hasresources available to contribute to MANX

MANX proposal has 34 signatories;

MICE is already stretched on some fronts

Resources look very tight

Run MANX

Maintain: Target Beamline Decay Solenoid MICE detectors DAQ Software…

Estimate ~9 FTE simply to maintain MICEinfrastructure and instrumentation fairlycomfortably


SUPPORT – Stating the obvious, perhaps

• MANX proposal assumes much of MICE will exist– MICE is a collaboration

• Infrastructure is not (yet) a facility– Operated by MICE collaborators

• Instrumentation is not owned ‘in common’ by MICE– Owners of instrumentation may have own preferences

or funding agency constraints– ‘MICE’ itself cannot agree to support any new initiative

• MANX – or any new cooling experiment – at RAL would probably require substantial UK involvement– RAL is small part of MICE

• Not same relationship to users as CERN or Fermilab


SUPPORTStraw poll of some members of MICE with some responsibilities for infra-structure or instrumentation was conducted in order to obtain an idea of support for a non-specific future experiment & indication of attitude of funding agencies. It was indicated that ‘No comment’ would be a valid response. (Five still to reply.)

Responses (paraphrased) : ‘No comment…, sine qua non to finish MICE ’‘Will discuss & respond shortly’‘Difficult to foresee future; …will consider’‘Would hand over [ ] to RAL; involvement would depend on details of experiment’‘Would support… if MICE supports & US supports strongly’‘NF is important; would support [infrastructure] & recruit’‘Probably welcomed by STFC… support the development of a proposal for an appropriate and realistic experiment with enthusiasm …Hall… & UK contributions… would be available’

Qualified support; STFC would most likely support a new initiative. Would require UK & other groups to agree on a program & apply for new funding.


ADAPTING MANX to MICE• 3m MANX not well matched to MICE instrumentation• Shorten MANX

– MICE instrumentation should work 150 – 240 MeV/c– Shorten MANX to ~1.5m

• 240 MeV/c in 150 MeV/c out (v. roughly):– Should still be plenty of cooling

• Would ease upstream PID • Would ease matching & engineering

– Match into 4 Tesla instead of 6 Tesla• Smaller He requirements

– ~1300 litres» Still large; still couldn’t use LH2 systems

– Downstream TOFs would still require space & area (~1m2)• Use TPC instead (?)


SUMMARY (1 / 2)Off-Axis MANX may have engineering difficulties associated with transfer of non-axial forces, and torques on the spectrometer cold masses; it was not considered in detail.

Matched MANX has no obvious space incompatibilities; the space required for the helium system needs to be assessed.

The MICE LH2 systems would be too small for a LH2-filled HCC; the RF systems would be redundant.

The resolutions required by MANX are not precisely specified but the MICE spectrometers appear more than adequate for transverse measurements; the TOFs could provide a momentum resolution of 1% at 200 MeV/c to 3% at 350 MeV/c, but degraded by straggling.

The Cerenkovs would not be adequate at 350 MeV/c. The down-stream PID detectors may be too small, given the space required for the downstream TOFs for longitudinal momentum measurements.


SUMMARY (2 / 2)Engineering considerations (margins and forces) suggest it may not be possible to operate the MICE spectrometers to match into the 6T HCC field required for an input beam of 350 MeV/c. [To confirm]

A shortened MANX, using a 240 MeV/c input beam, could be a better match to the MICE instrumentation.

If the MICE software is to be used for MANX some effort should soon be devoted to its adaptation and use to demonstrate the performance of MANX with the MICE (or other) instrumentation.

The effort required to design… and install MANX, and to maintain the MICE infrastructure and instrumentation should be quantified. The timescale looks rather optimistic, given the available resources.

There is some support within MICE, with qualifications, for a (non-specific) second generation experiment at RAL; a strong UK presence would be necessary. MICE itself could not agree to any next experiment; a new collaboration would be required.


THE END

interim report on manx after mice

Documents

mice competence

mice hallscope

mice phase

mice spokesman informedafter

standard mice beams

mice executive board

manx spokesman

latest manx proposal