Transcript ALEPH in 1999 Alain Blondel, Ecole Polytechnique

International Muon Ionization Cooling Experiment
(MICE)
Motivations:
--Ionization cooling is an important ingredient in performance and cost
of a neutrino factory
--It has never been observed experimentally
--It is a delicate design and engineering problem
Goal
--design, engineer, build a section of cooling channel
that is part of a high performance neutrino factory design
--put it in a beam and show that it works as expected
(if not, understand why!)
The beam never lies.
This is a somewhat larger project that can be afforded by anyone of
the worlds regions => International collaboration
International Muon Ionization Cooling Experiment MICE
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MICE
An International Muon Ionization Cooling Experiment
International Muon Ionization Cooling Experiment MICE
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10% cooling of 200 MeV muons requires ~ 20 MV of RF
single particle measurements =>
measurement precision can be as good as D ( e out/e in ) = 1
SC Solenoids;
Spectrometer, focus pair, compensation coil
Liquid H2 absorbers
201 MHz RF cavities
Tracking devices:
Measurement of momentum angles and position
T.O.F. I & II
Pion /muon ID and precise timing
International Muon Ionization Cooling Experiment MICE
Tracking devices
T.O.F. III
Precise timing
Electron ID
Eliminate muons that3 decay
10% cooling of 200 MeV muons requires ~ 20 MV of RF
single particle measurements =>
measurement precision can be as good as D ( e out/e in ) = 10-3
Need same drawing for 200 MHz scenario!
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MICE: what will it measure?
Equilibrium emittance = 4200 mm. mrad(here)
Cooling
Performance
= 16%
Figure V.4: Cooling channel efficiency, measured as the increase of the
number of muons inside an acceptance of 0.1 eV.s and 1.5 p cm rad
(normalized), corresponding to that of the Neutrino Factory muon
accelerator, as a function of the input emittance [31].
28 MeV cooling experiment (kinetic energy Ei=200 MeV)
International Muon Ionization Cooling Experiment MICE
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Steering committee:
Europe: A. Blondel*1 , H. Haseroth, R. Edgecock
Japan : Y. Kuno
US:
S. Geer, D. Kaplan2, M. Zisman
*convener for coming year, 1 EU spokesperson, 2 US spokesperson
charge: assemble « technical team » representing two regions
in each of the following aspects.
Web site:
http://hep04.phys.iit.edu/cooldemo/
thanks to Yagmur Torun - [email protected]
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Participating institutes
(In parentheses: contact person in each institute)
Louvain La Neuve (G. Grégoire)
CERN** (H. Haseroth)
NESTOR Institute (L. Resvanis)
University of Athens (L. Resvanis)
Hellenic Open University (S. Tzamarias)
INFN Bari (G. Catanesi)
INFN LNF Frascati (M. Castellano, L. Palumbo)
INFN Legnaro (U. Gastaldi)
INFN Milano (M. Bonesini)
INFN Padova (M. Mezzetto)
INFN Napoli (G. Osteria)
INFN Roma I (L. Ludovici)
INFN Roma II (L. Catani)
INFN Roma III (L. Tortora)
INFN Trieste (M. Apollonio)
KEK (S. Ishimoto)
Osaka University (Y. Kuno)
ETH Zurich (A. Rubbia)
Paut Scherrer Institute (C. Petitjean)
University of Geneva (A. Blondel)
University of Zurich (A. Van der Schaaf)
Imperial College London (K. Long)
Rutherford Appleton Laboratory (R. Edgecock)
University of Birmingham (J. Wilson)
University of Oxford (G. Barr)
** pending the review of CERN activities in accelerator R&D which will take place in the
framework of the LHC cost-to-completion analysis.
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Participating institutes (ctd)
(In parentheses: contact person in each institute)
Argonne National Laboratory (J. Norem)
Brookhaven National Laboratory (R. Palmer)
Columbia University (A. Caldwell)
Fairfield University (D.Winn)
Fermi National Accelerator Laboratory (S. Geer)
Illinois Institute of Technology (D. Kaplan)
Lawrence Berkeley National Laboratory (M. Zisman)
Michigan State University (M. Berz)
Northern Illinois University (M. A. Cummings)
Princeton University (K. McDonald)
University of California Los Angeles (D. Cline)
University of California, Riverside/Indiana University (G. Hanson)
University of Chicago – Enrico Fermi Institute (K.-J. Kim)
University of Illinois at Urbana-Champaign (D. Errede)
University of Iowa (Y.Onel)
University of Mississippi (D. Summers)
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Technical Team leaders for the ionization cooling experiment
================================================
These nominees in charge of task forces have the following
responsabilities:
a) assemble the necessary team
b) if possible recommend a technical solution
c) foresee a description of the design/performance/cost estimate
of their part.
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a) concept development and simulations:
Alessandra Lombardi (CERN)([email protected])
Panagiotis Spentzouris (FNAL) ([email protected])
Robert B Palmer (BNL) ([email protected])
b) Hydrogen absorbers:
Shigeru Ishimoto (KEK) ([email protected])
Mary-Anne Cummings (Northern Illinois)( [email protected] )
c) RF cavities and power supplies
Bob Rimmer (LBNL) ([email protected])
Roland Garoby (CERN) ([email protected])
d) magnets
Mike Green (LBNL) [email protected]
Jean-Michel Rey (CEA Saclay)
e) particle detectors
Vittorio Palladino (INFN Napoli) [email protected]
Alan Bross (FNAL) [email protected]
f) beam lines
Rob Edgecock (RAL) [email protected]
Claude Petitjean (PSI) [email protected]
g) RF radiation
Jim Norem (Argonne)[email protected]
Ed McKigney (IC London) [email protected]
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Proposed agenda:
2001
Expose detectors to RF radiation (potential show stopper)
write first description of experiment with two options
US design (200 MHz) or CERN design (88 MHz)
US simulate CERN scheme [and vice versa if possible]
Evaluate availability and cost of main cost drivers:
RF cavities / amplifiers/ power supplies/solenoids
for each scheme
evaluate beams + host labs
1st workshop 25-27 October 2001, CERN
! 16 Nov. 2001 !
Chose technology + host lab, write +
submit LETTER OF INTENT
2002
Technical proposal
summer 2004
1st beam (debugging of spectrometers)
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MICE
Item
RF frequency
L-H2 absorbers
Experimental
solenoid
BASELINE SCENARIO
ALTERNATIVE(s)
200 MHz
88 MHz
SFOFO with focus pairs
One 4-cell cavity first
then 2 4-cell cavities
Single flip solenoid
With recirculating H2 circuit
60 cm(?) diameter, 3 T
120 cm long, DB/B=1%
active shield
30 cm diameter active area
Sealed with He cooling circuit
(KEK design)
.. 40 cm diameter with slits
for detectors
.. iron shield
International Muon Ionization Cooling Experiment MICE
COMMENTS
.. Difficult to present 88 MHz
in present CERN financial
situation.
88 MHz Nufact study should
continue!
Question: can same
set of magnets be used
with/without flip?
Should we foresee stronger than
minimum mag field to explore
stronger focusing?
Tunable thickness?
B field should be matched to
that of cooling cell
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MICE
Item
BASELINE SCENARIO
Host lab
Beam
Space required
Safety
spectrometers
Trackers
PID upstream
Downstream PID
PSI
ALTERNATIVE(s)
RAL
mE1 with energy 100-300 MeV
can begin with 100-200 MeV
beam preparation:
10 meters after last collimator
Experimental area > 15 X 4 m2
Scintillating fiber planes
> 4 planes with 3 coord each side
TOF with scintillators
Threshold Cerenkov
PSI Beam line exists, can be used
for particles, with P < 250 MeV/c
without delay. New collaborator!
RAL quite motivated.
Requirements well defined
Lateral space needed has not
been investigated carefully!,
foresee some margin.
Will request interaction with
host labto prepare proposal
Liquid Hydrogen + Magnetic field
In air with triple window
around hydrogen
COMMENTS
In vacuum/helium with
double window
Loss of resolution in air
to be evaluated
Silicon pixel may be needed Noise issue must be solved before
final design. Interest in thin
if noise level too high
pixel detectors for LHC upgrades
TPC- G ?
Fast cerenkov
Active absorber
International Muon Ionization Cooling Experiment MICE
PSI beam very clean
at low energy
Requirement not entirely clear
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PSI
The MICE Letter of Intent (LOI) was presented to the Research committee for the Ring Cyclotron
of the Paul Scherrer Institute (PSI) on Tuesday 8 January 2002; public presentations were made to
the users meeting.
(I was told by the chair of the committee that the talks of Dan Kaplan and Klaus Hanke were excellent
and answered many of the questions the committee and referees had, such as why is this experiment
important for the Neutrino Factory R&D.)
The Committee acknowledged the receipt of the LOI.
On request by the PSI management it did discuss the matter.
(conclusions given orally by the chair; from my notes… no written statement yet)
1. The Neutrino Factory project offers exciting physics and the proposed experiment fits well within
the project. The strategic goal of the experiment, which is to test a crucial part of the Neutrino Factory
design, was recognized.
2. The committee supports the aim of the experiment but expressed questions to the PSI management
as to whether it is appropriate for PSI to embark in it.
The concerns expressed by the committee were as follows
a) No formal organization (I.e. laboratory) is behind the project.
b) Hosting MICE will be a non-negligible investment for PSI; it is not realistic to believe that PSI would
not have to provide day-to-day support for the experiment,
c) the requested technical help to prepare a proposal and in particular the overview of safety aspects,
which need to be taken *very* seriously by the host lab, constitute already an important commitment.
d) PSI should consider the impact that this experiment might have on the ongoing research program
e) It is not clear to which extent this R&D is important for the future of the laboratory (does PSI want
to play a major role in the Neutrino Factory? This is a management decision!)
f) PSI is probably the best place to host the experiment, but not the only one.
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PSI
Next steps:
PSI management will meet and evaluate if there are sufficient interest and resources in the LAB
to host and support the experiment.
Discussions are taking place with the management of RAL to which the LOI was also sent, with the aim
of finding a solution by which the experiment can take place.
A formal answer to our requests will be given in about a month.
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From Ralph Eichler (PSI director), 23 january 2002, 7:27:55
Subject: MICE
Dear Alain,
Here is the status of decision making on the muon cooling:
1. Muon cooling is essential for muon collider (no way out). A muon collider is very far in the future and
most likely the radiation protection against neutrinos is a show stopper.
2. Three ideas for a neutrino factory exist (Japan, RAL, yours). Two of them need little or no cooling. Your
Proposal need the largest cooling.
3. I called John Wood director of RAL.
We agreed, the RAL and PSI should collaborate in a muon cooling experiment.
RAL will discuss internally if they want to have the experiment at RAL or PSI (time frame 2 weeks).
In case the cooling is at RAL, I offered to provide next year our superconducting muon channel n° 2
(5m 5T field presently in muE4). I have the impression that RAL is willing to inject much more
manpower into the project than PSI is able to provide.
I keep you informed of the next steps
With best regards, Ralph
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Answers (A.B.)
1. Muon cooling is essential for muon collider (no way out). A muon collider is very far in the future and
most likely the radiation protection against neutrinos is a show stopper.
The neutrino radiation issue for muon cooliders comes up at 3-4 TeV E.c.m. At lower energies, relevant
to the machines that have the unique capability of s-channel studies of Higgs bosons (SM and SUSY Higgses)
the neutrino radiation is not an issue.
2. Three ideas for a neutrino factory exist (Japan, RAL, yours). Two of them need little or no cooling. Your
proposal need the largest cooling.
There are scenarios for neutrino factories in US, Japan and CERN. The only project that has been fully
evaluated and costed is the US one, and it uses cooling. The CERN scheme relies even more on cooling.
The Japanes scheme is based on a series of several FFAGs which have not been costed and in which,
in a way similar to the “ring coolers”, it is an unsolved problem how to inject or extract the beam.
Having no cooling implies very large FFAG magnets – the horizontal aperture is large by construction,
but not the vertical one – which could raise the cost considerably. In fact there are studies on
how to implement cooling in an FFAG scheme, very similar to ring coolers; the hardware needed for such
cooling is very similar to that discussed for MICE.
3. I called John Wood director of RAL.
We agreed, the RAL and PSI should collaborate in a muon cooling experiment.
RAL will discuss internally if they want to have the experiment at RAL or PSI (time frame 2 weeks).
In case the cooling is at RAL, I offered to provide next year our superconducting muon channel n° 2
(5m 5T field presently in muE4). I have the impression that RAL is willing to inject much more
manpower into the project than PSI is able to provide.
Great! Thank you very much for handling this so seriously!
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This is the beam line mE4 which
will be dismantled at the end of
2002
This is the beam line mE1
where MICE could be installed
2002
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RAL…
In order to satisfy the requirements of the cooling experiment the following upgrades to the
beam are required:
· The pion peak must be moved up to at least 450 MeV/c;
· The background to the muons must be reduced by a large factor;
·
The rate of muons must be increased by increasing the length of the pion decay
channel.
Proposed upgrade
The beam required by the cooling experiment can be provided if the HEP Test Beam is
upgraded by:
Decreasing the angle at which particles are captured into the beam line: This will increase
the rate of particles entering the beam line as well as moving the peak of the captured
momentum to higher values;
Implementation of a solenoid pion decay channel: The length of the solenoid, typically 56 m, allows a significant fraction of the input pions to decay therein, and the high
longitudinal magnetic field (~5 T) captures the decay muons with high efficiency thereby
increasing the muon intensity. Simulations of these changes in the layout of the beam are in
hand.
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MICE and the LHC cost to completion crisis
It was anticipated that CERN would have very little resources to devote to the cooling expt.,
the LOI only ascribed the value of a refurbished RF power source (4 MW, essential), which
was assumed to come in a couple years (2004 or so)
CERN now has to concentrate on the completion of LHC, and the material budget for
Neutrino Factory has been radically cut (despite your protests, thanks!). The R&D is
assumed to be focused on the proton driver SPL, and possibly the target and horn(?).
At the same time, the director of accelerators (Carlo Wyss) has proceeded to convene a
European Muon Coordination and Oversight Committee (EU-MCOG) that will be
composed of leading personalities in Europe.
CEA- Saclay 2 members (Mosnier, Pierre)
IN2P3 2 members (Lieuvain, Katzanevas)
INFN
2 members (Napolitano, Pisent)
RAL
2 members (Peach, NN)
GSI Darmstadt
2 members (Hofmann, NN)
Julich, PSI, Novosibirsk, to be decided, DESY declined
This committee will review the R&D towards future neutrino beams and define a first set of
goals. It will also coordinate a fund request from the European Union.
Maybe this not all so bad after all. Lets go on.
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2002
The schedule of activities can be envisaged as follows, assuming all milestones are passed
successfully.
2002: Preparation of proposal and fund raising
·
IIntegrated simulation of experiment including beam, detectors and cooling cells
CRITICAL
· Evaluation of possible sources of systematic errors
·
Investigation of low equilibrium emittance lattice and of the compatibility with ring
coolers
· Continuous comparison of the 200 MHz and 88 MHz scenarios
· Test of detectors in X ray environment (already underway) CRITICAL
and choice of tracking devices
· Operation of 88 MHz cavity at CERN and of the test facilities at Fermilab
· Continued development of liquid hydrogen absorbers
Development of alternative schemes for absorbers
· Competitive design and cost estimates for the solenoids
· Constitution of a collaboration structure and more detailed distribution of tasks and
financial responsibilities
· Evaluation with the host laboratory of the requirements on space, facilities, safety and
radiation issues, and infrastructure
Submission
of proposal
in the
course ofMICE
2002.
International
Muon Ionization
Cooling
Experiment
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Observed dark currents in 800MHz cavity in
lab G.
The cavity could not be run at a gradient
higher than 5 MV/m without emitting one
electron or more within a time window of 20
.
ns. (i.e. 10-8 mA)
Q. Is this the right figure of merit?
Better probably: observed noise rate in
actual detector near the cavity.
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=> 6.70 MV/m
=> 4.65 MV/m
.43 X 4 cells = 1.7 m  11.5 MV for 1X 4 = 6.70 MV/m
16 MV for 2X4 = 4.65 MV/m
Is this correct?
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Simulations
Needed now:
understand what is the noise level that affects the performance of
each particular proposed detector scheme.
Understand tolerances on spectrometer solenoid
Needs simulation and reconstruction including noise and inefficiencies.
We have now
DWARF (Patrick Janot)
rather fast fortran code that contains a rudimantary helix fitting code.
Not impossible to implement
Exact field map (Bx,y,z of x,y,z)
Noise hits
Pattern recognition?
GEANT4 (Yagmur Torun)
Multipurpose tracking code.
Noise hits and pattern recognition and fitting code need to be added by hand too.
Will allow detailed detector response (for Cerenkov and e/mu absorber study)
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PRIORITIES
1. Find a home for the experiment
2. Understand the X ray issue and quantify it in terms of
particle detector performance
2.’ Develop reconstruction with noise and efficiencies
3. Chose detectors and finalize magnet parameters
4. Establish technical specs and cost estimates
4’ Distribute contributions and begin fund hunt mission
5. write proposal
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