Beta Beams Elena Wildner CERN For the Beta
Beta Beams Elena Wildner, CERN For the Beta Beam Collaboration 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 1
The Beta Beam Facility Collaborations P. Zuchelli: ” A novel concept for a neutrino factory: the betabeam”, Phys. Let. B, 532 (2002) 166 -172. FP 6 “Research Infrastructure Action - Structuring the European Research Area” EURISOL DS Project Contract no. 515768 RIDS) Ended 2008 http: //beta-beam. web. cern. ch/beta-beam/task/index. asp FP 7 “Design Studies” (Research Infrastructures) EUROnu (Grant agreement no. : 212372) Ongoing work from 2008 Lasts till fall 2012 http: //heplnv 135. pp. rl. ac. uk/joomla/index. php? option=com_content&view=category&id=9&Itemid=12 http: //heplnv 135. pp. rl. ac. uk/joomla/ Focus on a feasible and realistic facility with good physics reach 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 2
Neutrino Beams from Beta Beams Produce suitable beta (+/-) active isotopes n n n Accelerate beta active isotopes n n 2011 -07 -23 Available reaction energy of a specific isotope: Q The ions will get a maximum gamma boost gmax (En 2 gmax. Q) Store them and let them decay in a race track storage ring gmax n depends on the available accelerators n depends on the Z/A of the ion n is chosen for the physics reach wanted Merit factor: g/Q n Lower flux with distance n Higher x-sections with energy n Higher flux with g HEP 2011, Beta Beams, Elena Wildner 3
High-Q and Low-Q pairs Isotope 6 He 18 Ne A/Z 3 1. 8 decay b- b+ t 1/2 [s] 0. 81 1. 67 Q [Me. V] 3. 51 3. 0 Isotope 8 Li 8 B A/Z 2. 7 1. 6 decay b- b+ t 1/2 [s] 0. 83 0. 77 Q [Me. V] 12. 96 8 Li and 8 B 6 He and 18 Ne t 1/2 at rest (ground state) 1 ms – 1 s 1 – 60 s Nu. Base 13. 92 Higher Q-value gives higher n-energy, better x-sections but needs longer baseline 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 4
Beta beams at CERN n Use of CERN machines and infrastructures, existing technology n n n SPS allows maximum of 150 (6 He) or 250 (18 Ne) Gamma choice optimized for physics reach Opportunity to share detectors with astrophysics etc. ? ? ? n n beta beams (CERN) Relativistic gamma=100 for both ions n n Beta Beam are unique to CERN Bunching and first acceleration: ECR, linac Rapid cycling synchrotron Use of existing machines: PS and SPS Frejus, Gran Sasso, Canfranc, CNGS-Umbria, … Minimum n-rates after Decay Ring for physics reach n n 2. 9*1018 anti-neutrinos from 6 He 1. 1 1018 neutrinos from 18 Ne 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 5
CERN Beta Beams, Synoptic RCS SPL Dotted lines: alternative layouts Linac 4 Linac Molten Salt Loop ISOL target 6 He Baseline Collection PR 18 Ne n-Beam 8 B/8 Li 6 He/18 Ne ECR RFQ Linac 100 Me. V DR PS SPS PS and SPS existing RCS Decay Ring: Br ~ 500 Tm, B = ~6 T, C = ~6900 m, Lss= ~2500 m, g = 100, all ions 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 6
CERN Beta Beams, Synoptic SPL RCS Linac 4 ISOL target Dotted lines: alternative layouts Molten Salt Loop 6 He n-Beam Fréjus 18 Ne ECR RFQ 6 He/18 Ne Linac 100 Me. V DR PS SPS PS and SPS existing RCS Br ~ 500 Tm, B = ~6 T, C = ~6900 m, Lss= ~2500 m, g = 100, all ions 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 7
EUROnu physics Gamma 100 Gamma 350 M. Mezetto 2011 -07 -23 Gamma 100 HEP 2011, Beta Beams, Elena Wildner 8
CPV The systematic error estimation is important (detectors and beam) Beta beam neutrino flux can be calculated with current monitors in the accelerator. Extend plots (calculations) to higher theta 13 Reduction of Suppression needed for atmospheric background !!! 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner Flux Systematics SF Flux 9
CPV for the Fréjus option (6 He&18 Ne) Courtesy E. Fernandez, P. Coloma, C. Hansen • SF for atmospheric bg suppression: • serious constraint for b. Beams • Larger sin 22 q 13 • constraint is relaxed • larger bunches permitted • higher neutrino fluxes • Calculations should be extended • range beyond Chooz limit ? SF 2% seems sufficient for larger sin 22 q 13 (0. 6% used up till now) 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 10
CPV - n. Flux: Fréjus &Canfranc Courtesy E. Fernandez, P. Coloma, C. Hansen Nominal flux 2*Nominal flux 5*Nominal flux Fréjus, SF 1% Canfranc, SF 1% Fréjus: 18 Ne (1. 1 1018 n/year) & 6 He (1. 1 1018 n/year), g=100 Canfranc: 18 Ne (4. 4 1017 n/year, g=250) & 8 He (2. 9 1018 n/year, g=100) Other ion combinations may be efficient (A. Donini) Systematics from big fiducial volume not good Liquid Argon for Canfranc? 2011 -07 -23 Dashed Super. Beam to Fréjus Negative delta, matter effects give degeneracies with the mass hierarchy. Larger flux: no degeneracies, sensitivity for negative delta would increase, measurement of the mass hierarchy would be possible HEP 2011, Beta Beams, Elena Wildner 11
Mass Hierarchy Canfranc, Beta Beam setting: 8 Li@100 and 18 Ne@250 Flux: Nominal 2* Nominal 5* Nominal 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 12
Beta Beam Challenges n Isotope production ok now ! n n Atmospheric background suppression n n We loose particles from necessary collimation We get short intense bunches in the Decay Ring, may get unstable We can relax the suppression with recent results from T 2 K! High intensities in the existing machines n n n emmitters “easy” to produce, measured rates are sufficient n are more difficult: we can make them “on paper” Exp. for Ne 18 production verification are ongoing Beam instabilities Radiation Follow carefully the LHC injector upgrades The present machine cycles n Optimization possible 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 13
Isotope production rates Aim: 2. 0 1013 for low-Q More is possible Targets below MWatt is a considerable advantage! Planned experiments NB : 8 Li can be produced in rates comparable to 6 He using similar technology T. Stora, P Valko, E. Benedetto, E. Wildner… 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 14
Status, technologies n SF in Decay Ring (CERN, Cockroft) n n 60 GHz Ion Source (LPSC, CNRS, Grenoble) n n n Analysis of results available in September Decay Ring Redesigned (CEA) n n Collection ok Efficiencies now measured Measurements of x-sections 8 B and 8 Li (INFN, Legnaro) n n Tests of magnetic field for plasma containment ok Tests of assembly with 28 GHz (emmittances and efficiencies) 60 GHz gyrotron: awaiting reception 2012 Collection of high-Q ions from production ring (UCL, Louvain) n n RF hardware seems feasible Collective effects less important Collimation in Decay Ring (CERN) n Needs good solution 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 15
Implementation and Costing n n n How to chose a facilty? Performance/Cost Part of EUROnu mandate Synergy b. B/SB Safety has to be included 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 16
Conclusion n n T 2 K: Optimization for excellent physics reach is ongoing We can now reduce the SF for bg suppression (if T 2 K) n n Optimization of L/E n n Detector, WC but also Liquid Argon (EUROnu WP 5) Beam (alignment and current monitoring in accelerator) To be included in the comparison analysis (all facilities) Technical work in very good progress n n SPS can give gamma up to 250 for 18 Ne, may be interesting now Systematic errors need complete evaluation n n Flux will be considerably increased isotope production confirmed for 6 He, 18 Ne experiment ongoing Ion source being tested Cross section measurements for high-Q isotopes ok All results have to be iterated n Work on physics and accelerators in collaboration to be continued 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 17
Thank you for y o attention 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 18
Support slides 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 19
The Production Ring (8 B and 8 Li) Production of 8 B and 8 Li C. Rubbia, EUROnu proposal § § Aachen Univ. , GSI, CERN Gas Jet target proposed in FP 7: § too high density would be needed § vacuum problems Direct Production (D. Neuffer) with liquid film targets § Collaboration ANL (Benedetto/Nolen) § High-Q 8 B and 8 Li will not be considered for the time being § We will not explore the low-Q gamma 350 option 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 20
Managing intensities: “Ion Cocktails” Collective effects important Less collective effects Summary by A. Donini 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 21
Collective Effects limits, Decay Ring Only Transverse Mode Coupling Instabilities Recent Encouraging results, redesigned decay ring ! Phase slip factor changed C. Hansen, CERN & A. Chance, CEA 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 22
Atm. Background suppression 1014 ions, ~0. 5% duty (supression) factor can now be reduced Gives possibilities to give more neutrino flux 20 bunches, 5. 2 ns long, distance 23*4 nanosseconds filling 1/11 of the Decay Ring, repeated every 23 microseconds Work on HW feasibility by Cockroft institute/Lancaster Univ. G. Burt 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 23
Collection device § Measurements/Analysis ongoing for the collected 8 Li § Direct kinematics is possible, efficiencies to be evaluated § Setup and measurements for 8 B production and collection ongoing CRC, Louvain la Neuve 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 24
X-sections, Energies and Angles, Li and B 1 201 Measurements are finished ! INFN, Legnaro 2011 -07 -23 HEP 2011, Beta Beams, Elena Wildner 25
60 GHz Source status Puller electrode Plasma electrode Extraction insulator High voltage ring 28 GHz waveguide Conceptual design of the internal parts of the ECRIS prototype Delivery of the GANIL 28 GHz gyrotron to LPSC-LNCMI discussions for experiments Ion beam at 28 GHz with SEISM prototype (fall 2011) Magnetic field measurements, 30000 A (60 GHz) Plasma chamber Design of the High intensity beam line Follow-up the 60 GHz gyrotron building LPSC Euronu contract status Hiring a one year post-doc 400 A Power supply and magnet 2011 -07 -23 2010 -06 -04 HEP 2011, Beta Beams, Elena Wildner T. Lamy 26
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