Beta Beams ion production Elena Wildner 135 2009

Beta Beams ion production Elena Wildner 13/5 2009 New Opportunities in the Physics Landscape at CERN 1

Beta Beams, recall Aim: production of (anti-)neutrino beams from the beta decay of radio-active ions circulating in a storage ring (race track). q q n Beta-decay at rest q q q n Similar concept to the neutrino factory, but parent particle is a beta-active isotope instead of a muon. Piero Zucchelli: Phys. Let. B, 532 (2002) 166 -172 Both neutrinos and antineutrinos are needed n-spectrum well known from electron spectrum Reaction energy Q typically of a few Me. V (neutrino energy) Only electron (anti-)neutrinos Accelerated parent ion to relativistic gmax q q Boosted neutrino energy spectrum: En 2 g. Q Forward focusing of neutrinos: 1/g 6 He 13/5 2009 n Beta-beam boost g=100 n New Opportunities in the Physics Landscape at CERN 2

Choice of radioactive ion Beta-active isotopes species Production rates t 1/2 at rest (ground state) n q q n Life time 8 Li and 8 B Reasonable life-time at rest q q n 6 He and 18 Ne 1 ms – 1 s 1 – 60 s If too short: decay during acceleration If too long: low neutrino production Optimum life time given by acceleration scenario In the order of a second (at rest) Nu. Base Low Z preferred q q q Minimize ratio of accelerated mass/charges per neutrino produced One ion produces one neutrino. Reduce space charge problems 13/5 2009 New Opportunities in the Physics Landscape at CERN EURISOL DS 3

The EURISOL scenario Decay ring Br = 1500 Tm B = ~6 T C = ~6900 m Lss= ~2500 m 6 He: 18 Ne: g = 100 93 Ge. V 0. 4 Ge. V 8. 7 Ge. V 13/5 2009 Design report July 2009 ! New Opportunities in the Physics Landscape at CERN 4

Ion production (overview) n ISOL method at 1 -2 Ge. V (200 k. W) q q q n Direct production q q n >1 1013 6 He per second <8 1011 18 Ne per second Studied within EURISOL >1 1013 (? ) 6 He per second 1 1013 18 Ne per second 8 Li ? Studied at LLN, Soreq, WI and GANIL Production ring q q q Aimed: He 2. 9 1018 (2. 0 1013/s after target) Ne 1. 1 1018 (2. 0 1013/s after target) 1014 (? ) 8 Li >1013 (? ) 8 B Will be studied within EUROn Courtesy M. Lindroos N. B. Nuclear Physics has limited interest in those elements ->> Production rates not pushed! 13/5 2009 New Opportunities in the Physics Landscape at CERN 5

6 He (ISOL) Converter technology (J. Nolen, NPA 701 (2002) 312 c): Solid converter W avec protons 1/1. 4 Ge. V : standard technology at ISOLDE T. Stora, N. Thollieres, CERN n n Converter technology preferred to direct irradiation (heat transfer and efficient cooling allows higher power compared to insulating Be. O). 6 He production rate ~2 x 1013 ions/s (dc) for ~200 k. W on target could be expected. Measurements ISOLDE April 2009 13/5 2009 New Opportunities in the Physics Landscape at CERN 6

18 Ne (Direct Production) Geometric scaling n n n Producing 1013 18 Ne could be possible with a beam power (at low energy, 3040 Me. V) of 2 MW (or some 130 m. A 3 He beam on Mg. O). To keep the power density similar to LLN (today) the target has to be 60 cm in diameter. To be studied: q q q Extraction efficiency Optimum energy Cooling of target unit High intensity and low energy ion linac High intensity ion source Thin Mg. O target Ion beam Water cooled target holder and beam dump S. Mitrofanov and M. Loislet at CRC, Belgium 13/5 2009 New Opportunities in the Physics Landscape at CERN 7

New approach for ion production “Beam cooling with ionisation losses” – C. Rubbia, A Ferrari, Y. Kadi and V. Vlachoudis in NIM A 568 (2006) 475– 487 “Development of FFAG accelerators and their applications for intense secondary particle production”, -- Y. Mori, NIM A 562(2006)591 7 Li(d, p)8 Li 7 Li 6 Li(3 He, n)8 B 6 Li 20 -30 Me. V Chemistry with Boron? 13/5 2009 From C. Rubbia, et al. in NIM A 568 (2006) 475– 487 New Opportunities in the Physics Landscape at CERN 8

Beta Beam scenario EUROn (FP 7) Ion Linac 20 Me. V Ion production PR n-beam to experiment 8 B/8 Li Decay ring ISOL target, Collection Br ~ 500 Tm Neutrino Source 60 GHz pulsed ECR Linac, 0. 4 Ge. V PS 2 31 Ge. V SPS 92 Ge. V Decay Ring B = ~6 T C = ~6900 m Lss= ~2500 m 8 Li: 8 B: g = 100 RCS, 5 Ge. V Detector Gran Sasso 13/5 2009 New Opportunities in the Physics Landscape at CERN 9

ISOL, 6 He/18 Ne and 8 B/8 Li n 6 He q q n 18 Ne q q q n To be studied (Frame-work, Priority? ) 4 MW, 1 Ge. V on Hg? Rotating/multiple targets/large beams (Ta, W)? 8 Li q q n Tests of Be. O at 3 k. W at ISOLDE, analysis ongoing, encourageing! 2 Ge. V, 200 k. W, on water-cooled W Similarities with 6 He: should be possible To be measured 8 B q q q No beam ever produced Many ideas exist. Need development (Frame-work, Priority? ) B is reactive (difficulties to get it out of the target) 13/5 2009 New Opportunities in the Physics Landscape at CERN 10

ISOL, Rare Earth Metals n Other possible scenarios in a beta beam complex q q n Electron capture and beta decay, Barnabeu et. al* Electron capture: mono energetic n-beam One species only Interesting physics reach Yb… q q Similarities with 18 Ne To be studied (Frame-work, Priority? ) 4 MW, 1 Ge. V on Hg? Rotating/multiple targets/large beams (Ta, W)? * ar. Xiv: 0902. 4303 v 1 [hep-ph] 27 Feb 2009 13/5 2009 New Opportunities in the Physics Landscape at CERN 11

Acknowledgements n Participants in EURISOL Beta Beam Design study EUROnu FP 7 program specification n Discussions for the presentation n q q 13/5 2009 Thierry Stora Mats Lindroos New Opportunities in the Physics Landscape at CERN 12