Accelerated radioactive beams and the future of nuclear physics. David Jenkins

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1 Accelerated radioactive beams and the future of nuclear physics David Jenkins

2 Particle accelerators 1930s: Cockcroft and Walton 1990s: Superconducting niobium cavities

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4 Energetic Radioactive Beam Facilities in Europe CRC, Louvain-la-Neuve, Belgium delivering ISOL beams since 1989 GANIL, Caen, France delivering IF beams since 1984 (SPIRAL) ISOL beams since 2001 GSI, Darmstadt, Germany delivering IF beams since 1990 DRIBS, Dubna ISOL beams REX-ISOLDE, CERN delivering ISOL beams since 1960s Accelerated beams since 2001 EXCYT, Catania, Italy ISOL beams since 2006

5 ISOLDE

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9 PHYSICS WITH UNACCELERATED ISOL BEAMS

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11 Testing unitarity of the CKM matrix For beta decays between T=1 analogue states, the CVC hypothesis demands that: Tests of this can therefore be performed for N=Z nuclei with T=1 ground states or for T z =-1 nuclei (harder) The CKM matrix

12 Testing the CVC hypothesis High precision measurements needed (some of the most precise ever made on nuclei): Decay Q-value = Mass measurements Drives development of trapping technology Lifetime = High precision decay measurement with pure sample Drives techniques with radioactive beams Branching ratio = Locate as many non-analog branches as possible Other corrections e.g. radiative, isospin purity Present approach is to calculate and hope these are accurate Some possible scope for experimental measurements

13 JYFLTRAP IGISOL Cyclotron beam target Dipole magnet M/ M ~ 500 RFQ cooler Transfer line Purification trap Precision trap FC MCP } } Ion guide 30 kv Electrostitic switchyard Si 30 kv 7 T magnet Si Spectroscopy setup Counts FWHM = 20 Hz M/ M = Y Purification scan TOF-resonance in Precision trap Basic equations for mass determination 101 Zr 101 Nb 101 Mo 120 Pd f c f f 1 = 2π c,ref c q m ref B m - me = m - m e Frequency [Hz]

14 Ft-values Comparative half-life [s] C Hardy&Towner, PRC71(-05) JYFLTRAP CPT, Argonne ISOLTRAP, CERN 14 O 22 Mg 26 Al m 34 Cl 34 Ar 38 K m 42 Sc 46 V 50 Mn 54 Co 62 Ga 74 Rb 22 Mg, 34 Ar, 62 Ga and 74 Rb: Error bars in Ft dos not reflect the accuracy of Q EC - determination Q EC -values of 26 Si and 42 Ti in progress Z of the daughter nucleus New Q EC -value determinations (Penning Trap): 22 Mg M. Mukherjee et al., Phys. Rev. Lett. 93 (2004) Al m, 42 Sc, 46 V T. Eronen et al., Phys. Rev. Lett. 97 (2006) Ar F. Herfurth et al., Eur. Phys. J. A 15 (2002) Ca G. Bollen et al., Phys. Rev. Lett. 96 (2006) S. George et al., Phys. Rev. Lett. 98 (2007) V G. Savard et al,, Phys. Rev. Lett. 95 (2005) Ga T. Eronen et al., Phys. Lett. B 636 (2006) Rb A. Kellerbauer et al., Phys. Rev. Lett. 93 (2004) Mn and 54 Co T. Eronen et al., Phys. Rev. Lett. 100 (2008) V ud = (26) V V + V 2 ud + = (10) 2 us 2 ub

15 Precision branching ratio measurement for decay of 74 Rb A. Piechaczek et al., Phys. Rev. C 67, (2003)

16 Current status I.S. Towner and J.C. Hardy, Phys. Rev. C 77, (2008)

17 Accelerated ISOL beams

18 Nuclear Shape Coexistence 186 Pb

19 Which nucleus has best shape co-existence? Theory says 72 Kr, but experiment points at 68 Se..but the differences are subtle and a reflection of our advanced understanding P. Moller, R.Bengtsson, B.G.Carlsson, P.Olivius, T.Ichikawa Phys.Rev.Lett. 97, (2006)

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21 Reorientation in Coulomb excitation

22 70 Se 12 C 16 O 98 a.m.u. Isobaric contaminants A = 98 Break up 70 SeCO inside EBIS and charge breed up to a q = 19 + charge state (A/q ~ 3.68) eliminates isobars! REX-ISOLDE ε ~ 2.4% I b ( 70 Se) ~ 1.4 x 10 4 delivered to MB target

23 104 Pd( 70 Se, MeV/u normal kinematics

24 MINIBALL array Miniball is purpose-built for detection of low multiplicity gamma rays with high efficiency Segmented detectors and on-board pulse shape analysis are employed to locate point of first interaction to give superior Doppler correction

25 Particle Detection The scattered projectiles and/or recoiling target nuclei are detected in a CD detector which subtends angles of around o Total area = 50 cm 2 (93% active) 16 annular p + strips/quadrant 24 sector n + strips/quadrant Total of 160 discrete detectors Wafer thickness μm ΔE-E mounting

26 Coulomb excitation of 70 Se

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30 Testing theories of CP violation 223 Rn or 225 Ra? Tests of CP invariance in hadronic sector from static Electric Dipole Moment (EDM) of atom (best limits so far from 199 Hg on _ ~ θ QCD d d C T C S ε q SUSY ε Higgs χ LR ) Expect enhancement (by 10 2 ) of EDM in octupole radioactive nuclei, e.g. 223 Rn, 225 Ra

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34 FUTURE FACILITIES

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36 EUROPEAN ISOL ~ 65 elements > 700 nuclides HIE-ISOLDE fission fragmention spallation SPIRAL-2 intense fission

37 Scope of HIE-ISOLDE Energy Upgrade: The HIE-ISOLDE project concentrates on the construction of the SC LINAC and associated infrastructure in order to upgrade the energy of the postaccelerated radioactive ion beams to 5.5 MeV/u in 2014 and 10 MeV/u by 2015 Intensity Upgrade: The design study for the intensity upgrade, also part of HIE-ISOLDE, starts in 2011, and addresses the technical feasibility and cost estimate for operating the facility at 10 kw once LINAC4 and PS Booster are online. The 30 kw option (SPL beam) will be studied at a later stage

38 SC Linac Layout staged installation 1.2 MeV/u 3 MeV/u 5.5 MeV/u 8 MeV/u 10 MeV/u

39 ISOL: 5 MeV/u radioactive target 5 MeV/u radioactive beam 74 Kr High energies >50 MeV/u: Mainly single-step excitation Open to ambiguities in nuclear component 120 MeV/u radioactive beam ISOL: Sub-Coulomb studies cleaner. Multiple Coulex allows more detailed studies.

40 Shape coexistence in mean-field models: Skyrme M. Bender, P. Bonche and P.H. Heenen Phys Rev C74 (2006) HFB+GCM method Skyrme SLy6 force density dependent pairing interaction Restricted to axial symmetry : no K=2 states B(E2) values e 2 fm 4

41 Coulomb excitation of the two isomers in 68 Cu selected by laser ionisation

42 Experimental approaches largely depend on the beam intensity and resolution: Below 10 4 pps MAYA, ACTAR Below 10 6 pps SHARC, T-REX Up to 10 9 pps TIARA or alternatively A solenoid device

43 Finis