Summary of the 4th EUROnu WP4 meeting
CERN, Geneva, Switzerland
E. Benedetto, A. Chance, C. Hansen, S. Mitrofanov, T. Lamy, M. Loiselet, J. Payet, V. Palladino
(from NEu2012), C.Trophime, E. Vardacci, E. Wildner, V. Zorin
The meeting was held in Paris in the FIAP conference centre on the 19th of February 2010. The
meeting was hosted by CEA (J.Payet). The steering committee proposed to hold the next meeting
during September in Legnaro, hosted by INFN. We hope that this proposal will be accepted (no
presence in the Steering Committee Meeting from INFN, Legnaro).
Some important information:
The next EUROnu Annual Meeting will be held in Strasbourg, 2nd-4th of June.
Costing workshop at CERN, the 15th and 16th of March. For the costing workshop it is expected that at
least one representative from each collaborator is present. The site is
http://indico.cern.ch/event/EuroNuCostingMar2010 where you can register.
Discussions were intense during the meeting and in spite an “airy” program, we ran out of time and
the last presentation from E. Benedetto could not be entirely enjoyed by all participants due to travel
constraints. We will follow up suggestions about having dedicated meetings between the more general
The Steering Committee did approve of the way the project was guided and did not suggest
improvements. We are now convinced that the FP6 baseline has to be really consolidated, since the
intensities needed for the high-Q isotopes is so high (~5 times the needed decays with respect to FP6)
and that we do not have any realistic ideas how to accelerate these intensities for the time being, even
if we could provide the rates specified in the FP7 proposal at the level of the production (production
ring/collection/source). The production of 18Ne is consequently, again, an important subject for
research and discussion.
A demand for additional manpower (costing, accelerator physics and production) to CERN Council
via the CERN SPC (neutrino panel) has been elaborated, results expected in March.
All collaborators are encouraged to send information about meetings related to EUROnu WP4
(mailto: Christian.Hansen@cern.ch for upload on the General EUROnu web site www.euronu.org).
2 Decay Ring optimization: how to increase the flux of neutrinos
The new decay ring study aimed at increasing the flux of neutrinos to the detector by shortening the
arcs and increasing the straight section lengths, both the FP6 and the FP7 proposals would profit. New
magnets are needed 8T dipole (6T FP6) and a 70 T/m quadrupole (45 T/M FP6). We would gain 12%
of neutrino intensity. The optics has to be optimized further. The magnets would be closed midplane,
and will be studied for energy deposition, vacuum and radiation. Increased stored intensities by RF
manipulation did not give expected results and will be further studied.
3 Low energy side
The low energy part has been revised, for He and Ne. The main FP6 Linac 8 KeV has been designed
with two injection lines, one for He1+ and one for Ne 6+ accelerating up to 4(8) MeV/u for He(Ne).
At this energy the two species can be fully stripped and accelerated to 100 MeV/u. If He can be fully
stripped at ECR extraction we would need only one pre-acceleration stage. What is the contents of
He1+ and Ne6+ after the source? The Linac acceptance is 0.2 and the source extraction emmittance is
0.5 [pi mm mrad normalized]. Errors in energy for stripping calculations shown at the meeting
(thanks Marc) have been corrected. The repetition rates, ECR pulse lengths, time structure and
currents will be revisited and updated. Figures on production rates in FP6 Design report and other
documents are difficult to apply; we do not know what is meant.
It was agreed to set up a parameter table for the low energy part, up to the RCS, so that the
overall beta beam chain neutrino production can be revisited (including the results from the stability
4 Ion Production
Thierry could not come to the meeting which meant that Elena with expert knowledge of Marc went
through Thierry’s slides.
1014 6He/s can now be produced from 200 kW, 2 GeV proton beam in-target production. 50-
90% extraction efficiency from realistic big targets is expected (reduced scale experiment done at
CERN-ISOLDE to confirm these numbers; Weizmann, GANIL and CERN collaboration). We wait
for the final article (in preparation).
Ne production has been studied at LLN. Now, several possible reactions would be possible to
do at ISOLDE using protons in the 10kW to MW range (30 mA, 70 MeV) with molten salt, for
example NaF for 19F (target technology has been proven for molten metal targets at ISOLDE).
Simulations published in an IAEA report show that we can get the required intensities for Ne. If this
can be experimentally confirmed we are back on track for the FP6 ions (for production).
5 Ion ECR source
Studies and experiments of full stripping of the He atoms have been performed and show that there
could be some tuning of the ratio between He1+ and He 2+. Important is that we get one charge state
and then we may be able to strip at higher energy in the Linac. This seems to be the case.
The 60 GHz ECRIS Prototype have been successfully assembled in spite mechanical problems due to
non respected specifications from supplier. The decision to go ahead and try to fix the problems at
LPSC gave good results and the SEISM prototype could be assembled without water leaks or other
problems. Magnet time applications have been accepted at the lab. First field measurement in
February 2010 gave results close to simulations and future tests with even higher currents will be
made to validate the 28 GHz ECR operation. The 60 GHz program will be presented at the LPSC
scientific council and additional ANR funding is worked on.
6 8B and 8Li production
The production ring lattice and the first modelling of the gas jet target have been shown last
meeting. Now the tracking studies are working (full 6D) including ideas for the target inspired from
LHC collimations studies. This now permits tracking of a large number of particles (detection of
losses, emmittance and intensity evolution). The RF requirements and possible hardware solutions
have also been elaborated. Studies of the production ring internal target vacuum pumping and other
consideration (in collaboration with domain specialists from CERN and GSI) have shown that the FP7
proposal is at the limit of what is possible to realistically build. Alternative ideas and solutions have
been listed and a compilation of results and studies of the gas jet target and related problems will soon
Cross section measurements for 8Li exist and we will get the values of cross sections of the
produced particles with some error estimation in a near future. Measurements show that the largest
fraction of 8Li is emitted at an angle of 6-8 degrees. The analysed data will be used in ongoing
FLUKA simulations to compare with “classical” models in FLUKA. With this we can simulate data
for the collection device. Similar studies for B could be made at Dubna, in India (please Emanuele:
where?) or at INFN.
The collection device is being manufactured (8Li production, catching, extraction and
detection) and we are expecting results from the first tests scheduled for April. Hopefully we will then
be able to see some results for the EUROnu annual meeting in June.
7 Costing Workshop at CERN
Costing is one of the “selection” criteria for the Neutrino Facility for the future; we have no
costing in the FP6 Study except for the RCS. We will in principle get resources for this. There will be
a workshop at CERN where collaborators should participate. Similar criteria for the 3 facilities will be
used and the workshop will give the necessary instructions and tooling for doing the job.