ISOLDE – High-lights and Future Plans Maria J. G. Borge, CERN, PH-Dept

ISOLDE is the CERN radioactive beam facility In operation since 45 years The largest selection of isotopes of any ISOL facility worldwide Provides low energy or post-accelerated beams Run by an international collaboration Open to users from around the world 2 A Few Facts

ISOLDE at CERN 3 Facility LINAC2 PSB PS ISOLDE To be upgraded in intensity (2uA->6uA p to ISOLDE) and energy (1.4->2GeV) To be exchanged by LINAC4

ISOL elements 4 Isotope production via reactions of light beam with thick and heavy target PSB upgraded in intensity (2uA->6uA p to ISOLDE) and energy (1.4->2GeV)

ISOTOPE production in ISOL method 5

Produced Nuclei 6 Over 20 target materials and ionizers, depending on beam of interest operated at high temperature U, Ta, Zr, Y, Ti, Si, … 3 types of Ion-sources > 700 nuclides of over 70 chemical elements produced Target Reported by Thierry Stora

ISOLDE physics topics Many beams Good beam purity and quality High intensity 7 Nuclear Physics Nuclear Decay Spectroscopy and Reactions Structure of Nuclei Exotic Decay Modes Atomic Physics Laser Spectroscopy and Direct Mass Measurements Radii, Moments, Nuclear Binding Energies Nuclear Astrophysics Dedicated Nuclear Decay/Reaction Studies Element Synthesis, Solar Processes f(N,Z) Fundamental Physics Direct Mass Measurements, Dedicated Decay Studies - WI CKM unitarity tests, search for b-n correlations, right-handed currents Applied Physics Implanted Radioactive Probes, Tailored Isotopes for Diagnosis and Therapy Condensed matter physics and Life sciences

Physics & Users 8 User requirements: Higher energy for the post-accelerated beam More beams (intensity wise and different species) Better beams (High purity beams, low emittances, more flexibility in the beam parameters) => Need upgraded facility : HIE-ISOLDE Project Around 450 users (7% of CERN’s total) 25 countries; 100 institutions 175 experiments (in 4 years) 90 active experiments in 2011 Physics interest: Nuclear structure from decay and reactions Nuclear gs properties via atomic techniques Nuclear astrophysics Fundamental interactions Solid-state physics Bio- and medical physics

Experimental hall Target stations HRS & GPS Mass-sep. HRS ISCOOL RILIS REX-ISOLDE PS-Booster 1.4 GeV protons 3×10 13 ppp ISOLTRAP CRIS COLLAPS NICOLE MINIBALL and T-REX WITCH Travelling setups Post-accelerated beams 9 Collection points TAS Susanne Kreim Magdalena Kowalska Elisa Rapisarda

COLLAPS – Ne charge radii 10 Laser spectroscopy & Massses Geithner et al, PRL 101, (‘08) Marinova et al, PRC84, (‘11) Intrinsic density distributions of dominant proton FMD configurations

WITCH Weak Interaction Trap for Charged particles -> fundamental studies Goal: determine  correlation for 35 Ar with (  a/a) stat  0.5 %

WITCH 12 M. Beck et al., Eur. Phys. J. A47 (2011) 45 M. Tandecki et al., NIM A629 (2011) 396 S. Van Gorp et al., NIM A638 (2011) 192 First high-statistics run in Nov 2011: under analysis PRESENT16 Nov 2012 June 2011 data -> energy spectrum of recoiling ions with a retardation spectrometer Use a Penning trap to create a small, cold ion bunch 35 Ar

REX-ISOLDE 13 Total efficiency : % 1 + to A/Q = 3 – 4.5

Post-accelerated beams 14 MINIBALL Travelling setups

First spin-polarized beam (8Li) produced with tilted foils after the REX linac (300 keV/u). REX separator and linac successfully tested with A/q=2 => important for TSR. Difficult 6 He beam through REX to Optical Time Projection Chamber (OTPC). βd 21 Na(p,α) 18 Ne to study 22 Mg states. 30 Mg(p,p’) to study 31 Mg excited state by its Analogue Resonance Characterize 13 Be from analogue resonance sin 13 B populated by 12 Be(d,n) with MAYA REX-ISOLDE 15 αd

Experimental set-up: T-REX &MINIBALL beam MINIBALL 24 HPGe 6-fold segmented  ≈ 1.3 MeV beam … shown is GEANT4 Implementation of set-up Talk by Elisa Rapisarda!

Near Future: HIE-ISOLDE project 17 Energy Upgrade: The HIE-ISOLDE project construction of the SC LINAC to upgrade the energy of the post- accelerated radioactive ion beams to 5.5 MeV/u in 2015 and 10 MeV/u by 2017 Intensity Upgrade: The design study for the intensity upgrade, also part of HIE-ISOLDE, started in 2011, and addresses the technical feasibility and cost estimate for operating the facility at 10 kW once LINAC4 and PS Booster are online. Approved Dec 2009 Offically started Jan 2010 Yacine Kadi project Leader Budget 40 M$ Tomorrow Yacine kadi Richard Catherall

The ISOLDE Collaboration ISOLDE is run by a collaboration comprising 13 countries and CERN. Each country pays a annual fee of 60 KEuros. This budget is used to support experiments, buy common equipment and consumables, pay some personnel (visitors, secretary….) and contribute to upgrades (HIE-ISOLDE…) Each county has a representative on the Isolde Collaboration Committee which meets three times a year. The chair is currently Dr Yorick Blumenfeld (France)

Summary and outlook The Future of ISOLDE is bright. With nearly 50 year of operation ISOLDE remains as pioneering ISOL-installation both at the level of designing new devices and production of frontier Physics. ISOLDE experiments cover many techniques enabling to answer many physics questions. Synergies between the different experiment techniques hunting for isolating very pure beams has been lately very successful  Complementarity is important! 19

Thank you for your attention 20

Coulomb excitation & Miniball 21 Observables: Transition energies and intensities Information: reduced transition matrix elements => Study collectivity and deformations Miniball setup: highly efficient gamma detectors and particle detector target REX- ISOLDE E <3 MeV/u PPAC detector Beam CD – detector Double sided Si strip detector Beam dump Beam impurities  E-E detector Ge  detectors Miniball + T-REX setup (Si detector barrel): gamma detectors and particle identification Typical reactions: one or two-nucleon transfer (d,p), (t,p) … In inverse kinematics Observables energies of protons (+ E g ) (single-particle) level energies angular distributions of protons (+  -rays) spin/parity assignments (relative) spectroscopic factors particle configurations

Coulomb excitation of 72 Kr 22 Oblate 72 Kr expected The technique Coulex Spectra - number of counts in 710 keV depends on the shape of 72 Kr Doppler Corrected for 104 Pd target excitation Doppler Corrected for 72 Kr projectile excitation: 150 counts in 710 keV line

Decay studies 23 Travelling setups

Beta-delayed fission Beta-delayed fission is believed to affect the abundance of heavy elements as it contributes to recycling heavy elements in the course of the r-process. N/Z ratio too exotic for current facilities and U-Cf region too close to stability for challenging models. P-rich region offers a very challenging group to probe our understanding of the process. 180,182 Tl, 192,194,196 At, 200,202 Fr have been studied at ISOLDE. 24 Fr: L.Ghys, Ph.D thesis KULeuven At: V. Trusdale, Ph.D thesis U of York Tl: PRL 105 (2010) Tl 180 Hg*  90 Zr+ 90 Zr (?) 196At 194At βDF 180 Tl

Proposed stage 1 HEBT layout

New setups in the summer Successful experiments with new setups & by new groups:  6He with opt. time-proj. chamber (Warsaw);  21Na and 31Mg with REX scattering chamber (Lund and Tokyo);  34Mg with fast tape-station (Bucharest)  12 Be with active target MAYA (Leuven, GANIL); 26

Motivation for the TSR Higher intensities and cooler beams than in-flight storage rings 2. Compared to thick experimental target and direct beam from the post- accelerator: + no background from a target container or a beam dump + reduced energy straggling for projectile and reaction products in thin target + smaller beam size ‐> improved kinematic corrections for reaction products + decreased detector dead-time as CW beam (REX and HIE-ISOLDE pulsed) Possibility to use extracted beam with excellent optical qualities

Physics Cases discussed for the TSR 28 1.Half-life measurements of 7 Be in different atomic charge states 2.Capture reactions for astrophysical p-process 3.Nuclear astrophysics through transfer reactions 4.Nuclear structure through transfer reactions 5.Long-lived isomeric states 6.Atomic effects on nuclear half-lives 7.Di-electronic recombination on exotic nuclei 8.Atomic physics experiments 9.Neutrino physics 10.Laser spectroscopy experiments in the storage ring

Nuclei production and selection 29

Targets Over 20 target materials and ionizers, depending on beam of interest U, Ta, Zr, Y, Ti, Si, … Target material and transfer tube heated to 1500 – 2000 degrees Operated by robots due to radiation 30 Converter Target Standard Converter Target p+

Ionization Surface 31 Plasma Lasers

Converter target 32

Going beyond the limits with the LIST Neutron-rich beams at ISOLDE are limited by the high isobaric contamination from Fr and Ra. The Laser Ion Source Trap can suppress those beams by up to a factor The first decay spectroscopy of 219 Po has been performed as well as hfs studies on Po. 33 D.Fink, Ph.D thesis U. of Mainz