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Summary WP4, Beta Beams, Elena Wildner 1
Beta-Beams (WP4) Summary
Elena Wildner, CERN
12010-06-04
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 2
Outline
Events Milestones/Deliverables Highlights Conclusion
22
2010-06-04 3Summary WP4, Beta Beams, Elena Wildner
Overview of events (I)
3
2 WP4 full meetings 3rd WP4 meeting, 25/11/09, Grenoble (LPSC) 4th WP4 meeting, 19/02/10, Paris (CEA)
Meetings Legnaro, CEA
Nufact09 Europeean Strategy for Future Neutrino Physics, CERN (1-3
Oct, 2009) ISOLDE Workshop and Users Meeting, CERN (18-20 Nov,
2009) EPIPHANY 2010, Krakow (5-8 Jan, 2010)
Physics in underground laboratories EuCARD, RAL (April 2010)
NEU2012 network meeting
2010-06-04 4Summary WP4, Beta Beams, Elena Wildner
Overview of events (II)
4
Fermilab, Batavia, USA, Productin Ring Design and cooling workshop organized by D. Neuffer
GSI, Darmstadt (O. Boine-Frankenheim, C. Dimopoulou) Cooling and Internal Gas Targets for production ring Large interest 15 Participants: NTU-Athens , GSI(6), University of Frankfurt (3),
CERN (3), University of Münster, FZ Jülich (2) GSI joins as associated institute to WP4 (has to be approved by
EUROnu)
Costing WS, CERN Two BSc theses from Aachen (summer 2009) Aachen will contribute with one student for 3 months (summer
2010) Some 10 publications written (pending publication)
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 5
Beta Beam scenario EUROnu, FP7
.
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 20 MeV
8B/8Li
PS
We are working on all parts!!!Exception Ion Linac 25 MevPS2 has been eliminated from the scene
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 6
Beta Beam scenario EUROnu, FP7
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 20 MeV
8B/8Li
PS
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 77
Intensities needed: Some scaling L ~ <E > / m2 ~ Q , Flux ~ L−2 => Flux ~ Q −2
Cross section ~ <E > ~ Q Merit factor for an experiment at the atmospheric oscillation maximum:
M= Q Decay ring length scales ~ (ion lifetime)
With FP7 ions we need ~ 5 times more ions (same & longer baseline)
Other detector technology at higher energy requires another factor ~ 2 ?
FP-7 proposal did not address these facts
Assumed shortfall of 18Ne intended to be solved by producing Li/B ions
The FP7 assumption was to accelerate a similar number of ions for He/Ne and Li/B.
Conclusion: Baseline beta beam scenario milestone B/Li will not be met
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 88
Strategy, Beta Beam, Accelerators Work on 6He and 18Ne ions, push of production has given results
Experiments for He, results tell us production is ok Ne ok on paper but needs one FTE more for experimental verification
(CERN, LLN).
Satisfactory results to achieve good neutrino flux (He and Ne) the beta beam baseline is the Frejus Option (He and Ne)
Accelerator Complex is calculated first for the He and Ne Option Beam stability Decay Ring Optimization Superconducting Magnets in Decay Ring Collimation
The engagements for B and Li is continued by WP4 partners
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 99
Beta Beam scenario 6He/18Ne
Neutrino
Source
Decay Ring
ISOL target
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
6He: = 100 18Ne: = 100
SPS
RCS, 1.7 GeV
-beam to Frejus
Linac, 100 MeV
60 GHz pulsed ECR
280 GeV
Ion production18Ne
PS
SPL Linac 4 ?
6He
Ion production
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 1010
Beta Beam scenario 8Li/8B
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 1.7 GeV
-beam to GranSasso/Canfranc
Linac, 100 MeV
60 GHz pulsed ECR
Existing!!!
280 GeV
Ion productionPR
Ion Linac 25 MeV, 7 Li and 6 Li
8B/8Li
PS
Milestones
2010-06-04 11Summary WP4, Beta Beams, Elena Wildner
4.1 Baseline Beta-Beam scenario 4 12 Documentation
reviewed
4.2 Design of collection device 4 15 Drawings qualified by external expert
4.3 Lattice frozen for production ring 4 18 Optics qualified by
external expert
4.4 New decay ring optics for 8Li and 8B 4 21 Optics qualified by
external expert
We can today give the needed fluxes with 6He and 18Ne. Experimental verification now urgent!! After collective effects studies and revisiting RF scenarios, the parameter list will be completed.
Collection device is designed and assembled. Tests ongoing.
Basic lattice frozen, cooling simulations will tune the lattice
Deacy ring optics done also for B and Li.We have in addition a new decay ring design giving some extra 10% in neutrino flux (for Ne and He also).
WP Month
Milestones (contd & Deliverables)
2010-06-04 12Summary WP4, Beta Beams, Elena Wildner
6.3 Scenarios for the B and Li Beta Beams 6,4 24 Report
reviewed
6.4 Physics performance of all facilities with update of fluxes
6,5,4 24 Report reviewed
Results from the barrier bucket study, (B and Li) confirms we have to keep SF with some minor relaxation. For He and Ne we stay with the original basic parameters.
Detector performance for high-Q? We have assumed a factor 2. Can this be improved? Do we need to do development of a new accelerator complex to accelerate B and Li?
D8 Collection device construction 4 15 Prototype
D12 Report on the experimental validation of
the collection device for Li-8
4 15 Prototype
D13 Bunching performance evaluation 4 7 Report
Device constructed.
Barrier buckets not feasible, neither for B and Li or Ne and Ne. For the decay ring we have no better results than the merging process and stand with the FP6 results. Other machines: Rf to be revisited for all ions
Will be delivered after tests (for annual report)
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 13
Beta Beam scenario EUROnu, FP7
.
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 25 MeV
8B/8Li
PS
2010-06-04 14Summary WP4, Beta Beams, Elena Wildner
The production Ring
14
Supersonic gas jet target, stripper and absorber
7Li6Li
7Li(d,p)8Li6Li(3He,n)8B
Lattice design operational Target model (Bethe-Bloch) Beam cooling is observed (1000 turns) Lattice to be adapted Wedge angle has effect on coupling Chromaticity to be tuned (resonances) Equilibrium emmittance fits with theory RF feasable (4 MHz, 300 kV), ACOL cavities
Gas Jet target proposed in FP7: too high density to be realistic Vacuum problems Target model has to also include single scattering of we use less dense targets Try Direct Production (D. Neuffer) with spectrometer magnet?
E. Benedetto
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 15
Beta Beam scenario EUROnu, FP7
.
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 25 MeV
8B/8Li
PS
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 16
PR: Gas Jet Targets and Cooling (GSI)
We need 10 19 cm-2 !!
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 17
PR Feasibility: Vacuum
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 18
X-sections, Energies and Angles, Li and B
18
8B production experiments are being planned at Legnaro for inverse kinematics.
If we need to change the production of B and Li in the production ring (liquid target, direct kinematics) experiments could be envisaged for this reaction. Funding may be limiting.
Inverse kinematic reaction:7Li + CD2 target E=25 MeV
Results for cross-sections and angular distributions have been presented.
E. Vardaci
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 1919
RipeN RipeN RiRivelatori velatori peper r NNeutroni a LNL eutroni a LNL
12.7cm x 12.7 cm
24 BC501 cylindrical Liquid Scintillators
V. Kravchuk
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 20
Challenge: collection device A large proportion of beam particles (6Li) will be scattered into the collection device.
Production of 8Li and 8B: 7Li(d,p) 8Li and 6Li(3He,n) 8B reactions using low energy and low intensity ~ 1nA beams of 7Li(10-25 MeV) and 6Li(4-15 MeV) hitting the deuteron or 3He target.
Tests on collection device:The collection device has presently a welding problem.
September 2010 to finish with 8Li.
Research on B will follow.
Semen MitrofanovThierry DelbarMarc Loiselet
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 21
Decay Ring
21
A .Chance
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 22
Beta Beam scenario EUROnu, FP7
.
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 20 MeV
8B/8Li
PS
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 23
Decay Ring Intensities
23
• A first study of the dynamic aperture has shown that it was large enough to accept the beam.
• Due to the blowing up in the longitudinal phase space, it was shown that a dedicated collimation section was needed in the DR.
• The peak beam intensities are unprecedented (several Amps in average, hundreds of Amps peak).
• The beam loading in the cavities must be studied (Cockcroft Institute could work on this as associate partner).
• To gain 10% of neutrinos, we increased the field from 6 to 8 T in the arc magnets and shorten the arcs from 970 to 675 m
• The injection region will be moved from the arc to the straight section.
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 2424
Duty factor and RF Cavities
....
20 bunches, 5.2 ns long, distance 23*4 nanosseconds
filling 1/11 of the Decay Ring, repeated every 23
microseconds
1014 ions, 0.5% duty (supression) factor for background suppression !!!
24
Erk Jensen, CERN
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 25
Radiation issues
25
• Open midplane magnet for Decay Ring exists (2009)
• Internal absorbers between short dipoles• Result not entirely satisfactory (2008)• Magnets at quench limit
• Thick liners in the magnets an alternative• Modelled in FLUKA for the time being
results not convincing• Thicker liners (other materials)• Back to absorber design• We have to check vacuum issues• Work on collimation system to be continued (hibernating...)
• SPS is still to be looked at• Other machines ok (within limits from CERN rules)
E. Wildner
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 26
DR Arc Magnets
26
z axis (cm)
Pow
er
dep
osi
ted
(m
W/c
m3)No significant improvement when using 1cm thick liner (stainless steel)Quads have similar problems
• Decay losses concentrated on the horizontal plane• Normalized to a decay rate in half of the arc:
He: 3.74x1010 decay.s-1
16
14
12
10
8
6
4
2
0
E. Bouquerel
Summary WP4, Beta Beams, Elena Wildner
Options for production
2010-06-04 27
Type Accelerator Beam Ibeam
mA
Ebeam
MeV
Pbeam
kW
Target Isotope Flux
S-1
Ok?
ISOL & n-converter
SPL p 0.1 2 103 200 W/BeO 6He 5 1013
ISOL & n-converter
Saraf/GANIL d 15 40 600 C/BeO 6He 5 1013
ISOL Linac 4 p 6 160 700 19FMolten NaF loop
18Ne 1 1013
ISOL Cyclo/Linac p 10 70 700 19FMolten NaF loop
18Ne 2 1013
ISOL LinacX1 3He > 170 21 3600 MgO80 cm disk
18Ne 2 1013
P-Ring LinacX2 7Li 0.160 25 4 d 8Li ?1 1014
P-Ring LinacX2 6Li 0.160 25 4 3He 8B ?1 1014
Experimentally OK
On paper may be OK
Not OK yet
Possible
Challenging
Courtesy T. Stora, P Valko
R & D !!!Needs some optimization
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 28
Recent Results for Production of 6He
5 1013 6He/s 200kW, 2 GeV proton beam (ISOLDE 2008)
N. Thiolliere et T. Stora, EURISOL-DS
T. Stora et al., EURISOL-DS, TN03-25-2006-0003
Aimed:
He 2.9 1018 (2.0 1013/s)
Production of 18Ne for Beta Beams Compatible materials (Ni-based alloys) up to 1000 ºC: Hasteloy N
Molten salt flow: 2.1 l/s (for ΔT = 100 ºC) Size of the irradiation cell: 24x15x7.5 cm3
Size of the diffusion chamber:
15x40x15 cm3
Cooling of the window is done
with the circulating molten salt.
Cross-section measurements done at LLN, to be compared with calculations
Molten salt loops presently set up LPCS, Grenoble: we will profit of this experiment.
EUROnu week in Strasbourg - IPHC P. Valko - CERN
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 30
ECR Source
30 30
• Available measurements periods last week of June• Extension of the magnet time access demand performed• If possible 13000 A measurements before end of July
Experiments, Gyrotron 37 GHz
MW pulse
Ion current of N3+ Microwave duration = 50 µsDuration of ion current = 20 µsIon current of N3+ = 2 мА
Ion current of Ar4+
Tсвч=70 µs Tсвч=60 µs Tсвч=50 µs Tсвч=40 µs
20 µs
Duration of ion current vs microwave durationJust noise
March 2010
V. Zorin
Modeling of Short Pulses
0 50 100 150 200 250T im e, m ks
0
0.4
0.8
1.2
Ion
cu
rren
t, a
.u.
M W
N +
N ++
N 3+
Simple mirror trap, L=37 cmMirror Ratio = 4MW=10 kW/cm2
Extraction voltage = 25 kVMW duration ~ 70 µs
0 50 100 150 200 250T im e, m ks
0
0.4
0.8
1.2
Ion
cu
rren
t, a.
u.
M W sim
N + s im
N ++ s im
N 3+ s im
Experiment Modeling
V. Zorin
Charge state distribution, short pulses
C2+ ArgonAr3+
Ar4+
Ar5+
Ar2+
C2+
N2+
C+O+
Nitrogen
H+
N+
N2+N3+
N4+
O2+
O3+
O+
C2+
C3+
C+
For 6He and 19 Ne we have to profit of produced intensities: extract one charge state and do the rest with Linac stage and strippers! Long Linac? CERN simulations ?
V. Zorin
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 34
Start overall simulations from
.
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 20 MeV
8B/8Li
PS
Optimize Linac with source dataPreliminary emmittances and beam sizes from ECR existEstimates on efficiencies (ECRin/ECRout) to be updatedSimulate beam up to RCS (and further)
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 35
Beta Beam scenario EUROnu, FP7
.
Neutrino
Source
Decay Ring
ISOL target, Collection
Decay ring
B ~ 500 Tm
B = ~6 T C = ~6900 m Lss= ~2500 m
8Li: = 100 18B: = 100
SPS
RCS, 3.5 GeV
-beam to experiment
Linac, 0.4 GeV
60 GHz pulsed ECR
450 GeV, p-eq
Ion production PR
Detector Gran Sasso (~ 5 times higher Q)
Ion Linac 20 MeV
8B/8Li
PS
Beta Beam Stability (all Beams) ???
Is the impedance limit compatible with DR special RF cavity for short bunches ???
Instability dependencies of bunch intensities are being investigated for all machines
(ongoing for DR and SPS)
C. Hansen, CERNC. Hansen, CERN
Transversal broad band impedance for 6He in DR istab.
Summary WP4, Beta Beams, Elena Wildner
The SPS RF programs are currently being developed in detail (A. Chancé, CEA) for the Instability Studies
Very challenging, may need re-design (optimization) of decay ring.
2010-06-04 Summary WP4, Beta Beams, Elena Wildner 37
Summary Milestones and Deliverables, ~ on time (baseline parameters for He and Ne) Good production18Ne on paper, we need experimental data (1 FTE needed) 6He has been produced with sufficient efficiency Production Ring feasibility
Results for production cross sections for Li are available, experiments for B being set up Collection device is assembled and tests are ongoing Gas jet target density needed is at least 4 orders of magnitude larger than presently used -
> vacuum problems (pumping). ECR source field measurements June and July Linac simulations ongoing DR and SPS
Collective effects: challenging beam conditions RF cavities: Collaboration Cockcroft being set up
Costing: PBS advancing, costing started One FTE needed for costing and safety
37