EUROPEAN NEUTRINO FACTORY COMPLEX
DRAFT MINUTES of the Meeting
held at CERN, 31 August 2001
Present:
Alain Blondel (chair), Friedrich Dydak, Enrique Fernandez, Helmut
Haseroth,
Vittorio Palladino, Michel Spiro, Carlo Wyss (Part-time)
Excused: John Ellis, Ken Peach,
Paolo Strolin(excused, delegated to Vittorio Palladino)
AGENDA:
1. Introduction: ECFA WG report & Snowmass (A. Blondel) 5'
2. overview of of CERN neutrino factory machine studies (H.Haseroth) 10'
3. discussion with C. Wyss
status of european MCOG and proposed structure. 30'
4. discussion on the structure of our studies of a neutrino factory
complex.
contribution by F. Dydak on R&D for neutrino factory
this disussion could include a discussion on the role of the steering
group, of its chair, and on a possible election.
** at that point will will probably need a coffee break!
5. status of yellow report articles
6. proton driver (SPL) physics study?
7. status of projects
-- Cooling experiment (A. Blondel, H. Haseroth
-- comment by F.Dydak)
-- Magnetic detector workshop (E. Fernandez)
-- status report on the CERN January workshop
on Large detectors for
proton decay, Supernovae and atmospheric neutrinos, and low energy
neutrinos from high intensity beams (M. Spiro)
8. Muon weeks and next plenary (V. Palladino)
9. next meeting
DISCUSSION
We welcomed Carlo Wyss, new CERN director of
accelerators, who had the kindness to attend the first part of the meeting.
1. Introduction: ECFA WG report & Snowmass (A. Blondel)
The report from the ECFA working group on the future of accelerator-based
high energy physics in Europe can be consulted here
.
(Temporary link, this is the final report but it has not been installed
on the ECFA pages yet)
The recommandations of ECFA insist very much
on accelerator R&D and on "a co-ordinated collaborative R&D effort
to determine the feasibility and practical design of a neutrino factory
based on a high-intensity muon storage ring;". The SPL and super-beam are
not mentioned in the executive summary, but are emphasized in the conclusions
and body of the report.
2. Overview of of CERN neutrino factory machine studies (H.Haseroth)
Helmut reviewed the ongoing R&D activities
towards a Neutrino Factory Complex in which CERN is involved. (transparencies)
The original idea as expressed by Kurt had the
goal of having ready two future options for CERN at the time when LHC is
running: CLIC and the Neutrino Factory. To achieve this requires work in
many areas: proton driver, target and magnetic collection (horn), phase
rotation and cooling, muon acceleration and storage ring, layout of the
accelerator on the CERN site and far detector locations.
On several topics, collaboration with european
laboratories (proton driver) or US laboratories (liquid Hg target tests)
is taking place, or being considered. (The cooling experiment was discussed
later)
M. Spiro made the remark that it was important
that the project has an implementation scenario in steps, with the SPL
and related physics first, followed by neutrino factory.
F. Dydak intervened at this point to express
his concerns about the cooling experiment. ( listed
here ). It was pointed out that many people did not share these opinions.
3. discussion with C. Wyss
Status of European MCOG and proposed structure.
The creation of a collaborative structure for neutrino factory R&D
follows a proposal by L. Maiani to organize a world-wide cooperation. The
first step is the creation of a European Muon Coordinating Group MCOG (see
the minutes of a meeting where the proposed
structure had been discussed). This step has been essentially completed
by Kurt Hubner, and Carlo Wyss will take it over. The steering group expressed
his best wishes for this enterprise in wich it is crucial that CERN takes
a leading role, and its desire to have this structure set-up rapidly. (C.
Wyss had to leave at this point)
4. discussion on the structure of our studies of a neutrino factory
complex.
Alain Blondel distributed a written description of the present structure.
( here
) This is similar (with a few updates) to what had been linked to the *news*
item of 22 May 2001. The natural evolution of this in the future favours
a structure based on the TESLA model, with a collaboration of laboratories
and funding agencies coordinating the accelerator R&D, associated to
physics working groups under sponsorship of ECFA; in this case, individual
R&D projects involving experimenters (such as HARP & MUSCAT now,
cooling experiment or detector R&D in the future) being the object
of specific proposals to the appropriate funding agencies.
It was generally agreed that a new structure would have to be discussed
with MCOG will be in place, and that we should continue as now for the
moment.
A discussion on the role and person of the convener of the muon steering group followed. It was agreed that Alain Blondel would continue to act as convener and chair of the muon steering group until the creation of a European Muon Coordination Group.
5. status of yellow report articles
A. Blondel described the status of the articles. Stopped muon, short
baseline neutrino and kaons have been finished for quite a while now, the
articles can be found on the web pages of the groups. The CERN neutrino
factory study (accelerator group) report is in almost final shape and the
muon collider article needs some more work. The neutrino oscillations part
is now urgently needed.
6. proton driver (SPL) physics study?
Given the possible implementation in steps with a SPL step followed
by the neutrino factory itself, the question was raised to organise a dedicated
study on physics with SPL. It was pointed out that several elements of
response will be present in the yellow report: stopped muons (which has
a reference and synergies to super Isolde) , low energy neutrino superbeam.
These studies should and will continue but the steering group saw no point
in launching a dedicated study at this moment.
7. status of projects
-- Cooling experiment (A. Blondel, H. Haseroth
-- comment by F.Dydak)
There was an extended discussion with presentation by Helmut Haseroth
( transparencies
21-24) and Alain Blondel ( transparencies
).
Following the agreement made in the london meeting ( see conclusions)
a collaboration has been set-up with the American Muon Collaboration, so
that the large hardware costs, as well as the expertise, be shared. The
aim is to build and measure a section a cooling that provides around 10%
cooling effect. ( a description of the goals and concept of the experiment
under discussion can be found here)
Helmut Haseroth pointed out that much has been already learned from this
effort, such as in particular the problem posed by field emmission in the
cavities.
To answer specifically some of Friedrich's
concerns,
the following remarks were made:
- the component testing is already underway and will continue.
- our american colleagues have now performed two feasibility studies
which demonstrate that a neutrino factory could be build....on paper!.
It is now the point of R&D to demonstrate that one could actually
build it. There is a need to demonstrate that ionisation cooling is indeed
technically feasible, i.e. that one is capable of building something that
cools. This goes beyond component testing. The success of a cooling experiment
will be a considerable asset when proposing this machine.
- It is agreed that there is no immediate physics outcome from the
proposed experiment, which is really accelerator R&D.
- The cooling experiment that is proposed is completely based on neutrino
factory design and targetted this way. It is a fact that it can be seen
as a first step in acquiring experience in cooling devices and that this
is of interest in view of muon collider R&D, but this can be considered
an advantage as well.
- the people preapring the experiment are very well aware of the financial
difficulties at CERN and for this reason are seeking to limit the CERN
contribution to a visible but affordable level.
- It is true that the cooling experiment in itself does not need
a large constituency in the physics community. The physicists involved
have to be willing to spend a few years doing R&D, but this is in fact
a very strong statement of interest. The experiment does, however broaden
the base with respect to the pure neutrino oscillation afficionados: among
the people interested one finds also stopped muon experts and people with
interest in muon collider.
- the cooling experiment, being based on a broad international collaboration
of accelerator physicists and experimental physicists, fits very well with
the recommendations of the ECFA working group. It is a motivating enterprise
and should speed up considerably the debugging process that is indispensable
to provide a reliable proposal and cost estimate at the time of LHC start-up.
In conclusion, a majority of the Steering group supports the preparation
of a cooling
experiment proposal. Friedrich Dydak, who did not, nevertheless acknowledged
the efforts
made to reduce the cost to CERN of a cooling experiment and declared
that he
would not oppose it.
7' -- Magnetic detector workshop (E. Fernandez)
-- status report on the CERN
January workshop on Large detectors for
proton decay, Supernovae and atmospheric neutrinos, and low energy
neutrinos from high intensity beams (M. Spiro)
There were dedicated meetings for the preparation of these events in
the afternoon.
8. Muon weeks and next plenary (V. Palladino)
The next muon week takes place 15-18 October.
9. next mug meeting
There will be a muon steeerng group with all conveners on the 16 of
October and it is proposed to hold a restricted muon steering group (only
MUG members) on 17 of October.
minutes prepared by Alain Blondel