Off-line Physics at ISOLDE during LS2 Richard Catherall ISOLDE Technical Coordinator on behalf of the ISOLDE Collaboration 10th LS2 Committee Meeting 31st March 2017 Off-line = stand-alone mode = winter physics = stable beam = “long-lived radioactive ion beams” All without protons

ISOLDE & HIE-ISOLDE: Operation during LS2 Justification: Minimize the impact of LS2 on the European Nuclear Physics program Make efficient use of the cool-down period before intervening in the target area 6 months cool-down before interventions (ALARA principle) Use beams for developments, machine characterization, experiment calibrations, testing to make efficient use of the facility for post-LS2 For MEDICIS, continue to provide isotopes for medical applications Winter physics program Long-lived RIBs Using previously irradiated targets and imported sources Cold check out Stable beam exercises Testing of FEs and beam line alignment Start and end dates to be defined (few months at least) ISOLDE Operation ISOLDE Operation MEDICIS Operation MEDICIS Operation 2019 2020 Non-LHC Experiments - Chamonix 2017

The ISOLDE Facility Class A labs MEDICIS Experimental hall HRS target HIE-ISOLDE HIE-ISOLDE Linac Target area Experimental hall Protons GPS target HRS target CRIS COLLAPS REX ISOLTRAP Travelling Setup MEDICIS Class A labs MINIBALL ISS SPEDE ISOLDE Decay Station

Radioactive Ion Beam Production The ISOLDE Facility can operate in stand-alone mode provided the infrastructure and equipment are operational. Target units can be tailor-made to produce stable or long-lived radioactive ion beams spallation fragmentation fission 1.4 GeV protons Front End (target station) Target Unit

ISOLDE Separators HRS GPS

Stable ion beam production (1) The 2 separators can provide stable beam for all low energy experiments AND REX/HIE-ISOLDE For the target, all we require is an ion source and a readily available stable element Impurities, chemical compounds, gas

Stable ion beam production (2) REX can provide beam for all experiments coupled to the HIE-ISOLDE beam lines. It has its own ion source and/or can use rest gas from the REX-EBIS to produce multi-charged ion beams. Experiments that could take beam from HIE-ISOLDE: MINIBALL HIFI ISS ACTAR SPECMAT

Radioactive ion beam production(1) Use previously irradiated targets Either after a previous physics run Depends on number of protons taken Or “charged” targets Targets that take protons at the end of 2018 but are kept cold to avoid release of radioisotopes. IS475 in 2010. 228Th (T1/2=1.913y) alpha decayed into the isotope of interest 224Ra. To produce long-lived radioactive ion beams Activities will be low but sufficient for experiments

Radioactive ion beam production(2) Import radioactive material from external institutes Material can be placed in a target unit either at the institute or at ISOLDE in the Class A laboratories Examples: 7Be T1/2 = 57 days graphite bombarded with 590 MeV protons at PSI 44Ti T1/2 = 60.4 years Chemical extraction from beam dump at PSI 169Er T1/2 = 9.4 days Enriched 168Er at high flux reactor ILL, Grenoble

Erbium-169: an example of imported sources Identified as a promising candidate for both imaging and therapeutic treatment of cancer cells

Required infrastructure and systems Cooling Targets, magnets, pumps, REX…. Ventilation Target area for target changes and hall for opening beam lines ISOLDE Vacuum system Controls Both local equipment and control system Beam diagnostics Power supplies and HT Magnets RP monitoring Controlled access Cryogenics and RF (for REX/HIE-ISOLDE only) The operation of these systems must be compatible with planned LS2 work both at ISOLDE and elsewhere

Required resources (operations) BE-OP for target and beam line operation including HIE-ISOLDE No piquet service Support for all other services Best effort RP for monitoring of activities, target changes, radioactive source handling EN-STI-RBS for target characterization and production EN-STI-LP for RILIS ionization schemes EN-STI for robot and conveyor system operation. EP-SME-IS for experiments

Proposition Keep ISOLDE operational from November 2018 till May 2019 With the exception of the Christmas break No maintenance Minimise the number of target changes Approximately 10 over the 6 month period Tailor targets to suit stable beam/physics needs Multiple possibilities from one target No on-call service Nights or weekends Operation during working hours only Defined schedule and accept experiments/developments proposed to the INTC and approved by the Research Board

Examples of possible experiments/developments REX/HIE-ISOLDE stable beam for machine characterization RILIS stable beam for development of new ionization techniques Ionisation of specific long-lived elements Target and ion source development And the following experiments….

Laser-polarization and beta-NMR setup LS2 request for long-lived beams Spin polarized short-lived nuclei can be used in the beta-NMR (Nuclear Magnetic Resonance) technique, which is part of an ISOLDE-based ERC Grant (EU-funded 5- year project) In 2016 spin-polarized long-lived isomers have been for the first time applied in a technique similar to beta-NMR (Nature, 2016): gamma radiation allowed sensitive NMR signals long-lived Xe isomer was used for an MRI (Magnetic Resonance Imaging) picture The feasibility of this approach for long-lived beams of other chemical elements produced at ISOLDE can be tested during LS2 The list of interesting long-lived candidates will be identified in summer/autumn 2017, when a master student will start working on the project Low energy 15

Laser-polarization and beta-NMR setup LS2 request for stable beams Spin polarized radioactive nuclei are interesting in various fields of research: Nuclear physics Fundamental interactions Biology (NMR, ISOLDE-based ERC Grant) and medicine (MRI) To allow efficient development of laser-polarized radioactive beams, a setup allowing to determine the degree of spin-polarization is under development Access to stable beams during LS2 will allow the development of laser- polarization schemes for several chemical elements: e.g. Ca, Cu, Zn, Tm, Lu: No break in 5-year ERC project, minimization of risk of scientific audit from EU Low energy 16

ISOLTRAP spectrometer RFQ cooler and buncher MR-TOF MS Bradbury-Nielsen beam gate Preparation trap Precision MCP 85Rb+ PI-ICR technique TOF-ICR technique Low energy - High-precision measurement of low electron-capture Q-values in search for candidates for the determination of the electron neutrino mass. - INTC document CERN-INTC-2014-038 (test case approved and will be measured before LS2; the two pairs of high interest, 159Dy-159Tb and 175Hf-175Lu, will be requested by addendum) F. Herfurth et al., NIM A 469, 254 (2001). R. N. Wolf et al., Int. J. Mass Spectrom 313, 8 (2012). G. Savard et al., Phys. Lett. A 158, 247 (1991). M. König et al., Int. J. Mass Spectrom. 142, 95 (1995).

Low energy Laser spectroscopy of light nuclear systems C, N, O , F → Key to understand the emergence of nuclear phenomena → Important benchmark for the development of nuclear theory → Not studied yet by laser spectroscopy C, N, O , F Require several developments that can be tested with stable beams Low energy → Optimize bunching of light ions with ISCOOL → ISCOOL properties and influence on the energy spread needs to be explored → The sensitivity to nuclear observables for different atomics transitions can be studied at CRIS/COLLAPS. → Novel developments are planned to improve sensitivity and resolution. LS2 -> A unique opportunity to perform these developments!

Stable beam for MIRACLS electrostatic mirror ion bunch laser Multi Ion Reflection Apparatus for Collinear Laser Spectroscopy (MIRACLS) new, ERC supported project at ISOLDE (EIBT-LS) promises large gains in experimental sensitivity for collinear laser spectroscopy simulation laser frequency [a.u.] counts r=1 000 MIRACLS conventional CLS r=1 Low energy Stable Beam from ISOLDE in 2020 (and 2019 if possible) indispensable to establish and optimise ion transfer from ISOLDE to MIRACLS prior to online beam; especially capture&trapping of bunches from ISCOOL benchmark entire measurement cycle develop second stage of project for nuclides with I≠0 requested beams: Mg, Sr, possibly Cd S. Malbrunot-Ettenauer, ERC StG EIBT-LS

Miniball during LS2 HIE-ISOLDE Coulomb excitation with stable/long-lived beams. 226Ra (T1/2 = 1600 a; beam from ISOLDE) 150Nd (enriched target; *any* stable beam from EBIS) Many more examples using EBIS beams as probes! Determine nuclear shape and study shell structure. HIE-ISOLDE 226Ra: pear-shaped? Powerful and flexible device/technique. Can do physics independent of ISOLDE; EBIS beams at REX/HIE energies.

ISOLDE Solenoidal Spectrometer (ISS) ISS solenoid in ISOLDE Hall Helical orbit spectrometer principle 4T solenoid HIE-ISOLDE Stable beam tests of new Si array for ISS during LS2 so ready for physics with radioactive beams after LS2. REX or HIE energies; HIE-ISOLDE preferred 86Kr(d,p)87Kr HELIOS – D.K. Sharp, PRC 87 (2013) 014312 Typical test beams: 22Ne, 38Ar, 86Kr, 136Xe Test beam tuning, recoil detectors, DAQ,… Physics with ”rare” stable/long-lived isotopes; - low abundance, target chemistry (gases/reactive elements), … Measure ISS improvements over HELIOS; - energy resolution, efficiency, …

HIFI Hie Isolde Fragment Identifier USING RADIOACTIVE BEAMS in INVERSE KINEMATICS HIE-ISOLDE identification of reaction products physical separation of isobaric beams or other beam contaminants Design Parameters large enough angular acceptance to pick up sequential decay products excellent angular resolution to allow kinematic reconstruction – missing momentum Zero-degree spectrometer @ Hie-Isolde The HIFI spectrometer will be a extension of the existing MINIBALL

MEDICIS The MEDICIS facility should be operational by the end of this year. A mass separator for the production of isotopes for medical applications Works on the same principle as ISOLDE in stand-alone mode But on a smaller scale Used or dedicated targets are transferred to the mass separator and operated Imported sources Could eventually work throughout LS2 No major interventions planned

Conclusion Efficient use can be made of the ISOLDE facility during the cooling period of LS2 to provide both stable beams and long-lived radioisotopes to in-house groups and fixed experiments Provided the various sub-systems are operational and a minimum of resources are available Stable beam will also be required in 2020 for Frontend commissioning and checking of the re-aligned beam-lines. All requests for 2019 will be channelled through the INTC in a dedicated session this June. All proposals are open to discussion

Thank you for your attention And thank you for the contributions by: Magda Kowalska Stephan Malbrunot Maria Garcia Borge Karl Johnston Ronald Fernando Garcia Ruiz Liam Gaffney Olof Tengblad