Mats Lindroos Future R&D: beta-beam Mats Lindroos

Production Test of target prototypes at e.g. TRIUMF (ISAC facility). Prototyping of a ring with ionization cooling for production of beta-beam isotopes. –C. Rubbia et co-workers (NIM A, In press), for production of radioactive ions and with long. and trans. cooling –Proposal by Y. Mori, NIM A 562(2006)591, for neutrons (and RIB) with trans. cooling using an FFAG.

Mats Lindroos Production ring with ionization cooling

Mats Lindroos A new approach Beam cooling with ionisation losses – C. Rubbia, A Ferrari, Y. Kadi and V. Vlachoudis in NIM A, In press “Many other applications in a number of different fields may also take profit of intense beams of radioactive ions.” 7 Li(d,p) 8 Li 6 Li( 3 He,n) 8 B 7 Li 6 Li Missed opportunities

Mats Lindroos Transverse cooling in paper by Carlo Rubbia et al. “ In these conditions, like in the similar case of the synchrotron radiation, the transverse emittance will converge to zero. In the case of ionisation cooling, a finite equilibrium emittance is due to the presence of the multiple Coulomb scattering.”

Mats Lindroos Longitudinal cooling in paper by Carlo Rubbia et al. “In order to introduce a change in the dU/dE term — making it positive in order to achieve longitudinal cooling — the gas target may be located in a point of the lattice with a chromatic dispersion. The thickness of the foil must be wedge-shaped in order to introduce an appropriate energy loss change, proportionally to the displacement from the equilibrium orbit position.” Number of turns 1)Without wedge, dU/dE<0 2)Wedge with dU/dE=0, no longitudinal cooling 3)Wedge with dU/dE= )Electrons, cooling through synchrotron radiation

Mats Lindroos Inverse kinematics production and ionisation parameters in paper by Carlo Rubbia et al. 7 Li(d,p) 8 Li 6 Li( 3 He,n) 8 B

Mats Lindroos Collection in paper by Carlo Rubbia et al. “The technique of using very thin targets in order to produce secondary neutral beams has been in use for many years. Probably the best known and most successful source of radioactive beams is ISOLDE.”

Mats Lindroos Reactions of interest for our application 27 Al( 4 He,n) 30 P ? –D.J.Frantsvog et al, PRC 25(1982)770: MeV, 480(50) mb 14 N( 2 H,n) 15 O ? –S.Takacs et al, NIM/B,211(2003) Mg( 3 He, 2 H) 25 Al ? –D.J.Frantsvog et al, PRC 25(1982)770: MeV, 430(70) mb

Mats Lindroos 6 He production from 9 Be(n,  ) Converter technology preferred to direct irradiation (heat transfer and efficient cooling allows higher power compared to insulating BeO). 6 He production rate is ~2x10 13 ions/s (dc) for ~200 kW on target. Converter technology: (J. Nolen, NPA 701 (2002) 312c)

Mats Lindroos ISAC at TRIUMF: First high power ISOL facility!

Mats Lindroos Ionization and Bunching Test of all concepts for efficient ionization and bunching.

Mats Lindroos 60 GHz « ECR Duoplasmatron » for gaseous RIB Very high density magnetized plasma n e ~ cm – 3.0 T pulsed coils or SC coils GHz / KW 10 –200 µs / = 6-3 mm optical axial coupling optical radial (or axial) coupling (if gas only)  1-3 mm 100 KV extraction UHF window or « glass » chamber (?) Target Rapid pulsed valve ? 20 – 100 µs 20 – 200 mA per bunch with high efficiency Small plasma chamber  ~ 20 mm / L ~ 5 cm Arbitrary distance if gas P.Sortais et al.

Mats Lindroos cryogenic trap target large plasma chamber efficient pumping (minimize charge exchange) + 20 kV multi electrode system 28 GHz + 37 GHz (15 kW) 5 T 2.5 T Source scheme D. Hitz, CEA

Mats Lindroos injection side extraction side 2 to 4 central coils hexapolar radial field several central coils for a good confinement nearby injection side and worse confinement at extraction side Magnets

Mats Lindroos Accumulation Design of accumulation ring

Mats Lindroos Accumulation at 400 MeV/u T 1/2 =1.67 s T 1/2 =17 s T 1/2 =0.67 s

Mats Lindroos The annual rate The annual rate at the EURISOL beta-beam facility is a factor of two below the annual rate assumed in most calculation –Is it possible to re-gain this missing factor of two within the present base- line?

Mats Lindroos High gamma beta-beam GammaRigidity [Tm] Ring length T=5 T f=0.36 Dipole Field rho=300 m Length=6885m Civil engineering Magnet R&D New SPS

Mats Lindroos Summary ProjectSubjectsCostOther communities ProductionProduction ring Target tests 5-25 MEuro FTE Nuclear Astrophysics, Hadron therapy Ionization and bunching 60 GHz ECR (2 types) BNL EBIS? 5-10 MEuro 5-10 FTE Nuclear physics Machine studiesHI acceleration Accumulation Higher gamma beta-beam 5-10 FTEHeavy ion physics, Nuclear physics

Mats Lindroos Conclusions –We need a larger beta-beam machine study community –For a fair comparison with neutrino factories we need to study the limits of the concept starting at “study 1”. Green field study –Neutrino beams at CERN Difficult to convince management that they should invest NOW in a neutrino beam study Feeling that the decision is far away Radiation safety aspects a concern