ISOLDE Decay Station

ISOLDE Decay Station
Name	ISOLDE Decay Station
Location	CERN, Geneva
Established	1990s
Facility type	Radioactive ion beam experimental station

ISOLDE Decay Station is a specialized experimental station at the CERN ISOLDE facility dedicated to decay spectroscopy of radioactive isotopes. It supports precision studies of nuclear structure, nuclear astrophysics, and weak interactions through decay spectroscopy and complementary techniques. The station interfaces with CERN infrastructure and serves international users from laboratories such as CEA, GSI Helmholtz Centre for Heavy Ion Research, Oak Ridge National Laboratory, TRIUMF, and RIKEN.

Overview

The ISOLDE Decay Station operates within the ISOLDE complex alongside facilities like the RILIS laser ion source and the HRS high-resolution separator, forming part of CERN experimental infrastructure connected to the PS Booster and Proton Synchrotron. It provides capabilities for beta-decay, gamma-ray, conversion-electron, and implantation studies, enabling experiments relevant to the r-process, s-process, and decay schemes affecting models associated with the Nuclear Shell Model and Ab initio nuclear theory. Visiting users from institutions such as University of Manchester, Lund University, KU Leuven, and University of Jyväskylä rely on the station for campaigns tied to international programs like those of the European Research Council and bilateral projects with INFN and CEA Saclay.

History and Development

The station evolved from early post-ISOLDE decay setups in the 1990s under leadership from researchers linked to CERN and contributors from University of Cambridge, University of Liverpool, and GSI. Upgrades have been staged in concert with programs at ISOLDE such as the HIE-ISOLDE upgrade and collaborations with ENSAR2 and EURONS. Significant milestones include integration of detectors influenced by developments at Lawrence Berkeley National Laboratory, adoption of digital data acquisition inspired by work at TRIUMF and Oak Ridge National Laboratory, and synergy with ion-beam manipulation techniques from JYFL Accelerator Laboratory in Finland.

Facility and Experimental Setup

The decay station is housed inside CERN experimental halls connected to beamlines controlled by ISOLDE beam delivery systems and the XTU control frameworks. It accommodates tape-transport systems used historically at ISOLDE Decay Station setups alongside implantation stations similar to those at GANIL and ISAC facilities. Experimental campaigns often coordinate with target and ion-source developers from ISOLDE operations, benefiting from laser ionization via RILIS and mass separation using the HRS and GPS separators. Users deploy setups compatible with beam prepared by personnel associated with CERN Accelerators & Beams (AB) Department and data workflows integrated with computing resources from the CERN IT department.

Instrumentation and Detection Systems

Instrumentation at the station includes high-purity germanium detectors comparable to arrays at ISOLDE, segmented silicon detectors analogous to systems at GSI and LNL-INFN, and plastic scintillators with designs influenced by Paul Scherrer Institute experiments. The station supports conversion-electron spectrometers reminiscent of those developed at University of York and gamma-ray tracking methodologies pioneered at Gesellschaft für Schwerionenforschung collaborations. Digital multichannel analyzers and acquisition systems draw on technology validated at Lawrence Livermore National Laboratory and Brookhaven National Laboratory. Cooling and vacuum systems are maintained following standards practiced at TRIUMF and RIKEN, while mechanical support and alignment reference procedures reflect engineering from CERN EN-MME and CERN EN-STI groups.

Research Programs and Scientific Contributions

Research at the station addresses topics related to magic numbers in nuclei investigated in contexts like the Island of Inversion, beta-delayed neutron emission relevant to r-process nucleosynthesis, and precision beta-decay measurements impacting tests of the Standard Model and searches for scalar and tensor currents. Results have informed nuclear mass models used by groups at Argonne National Laboratory and theoretical frameworks from Oak Ridge National Laboratory and University of Surrey. The station has contributed data for astrophysical reaction networks used by teams at Max Planck Institute for Astrophysics and Instituto de Astrofísica de Canarias. Collaborative publications have involved authors from Université Paris-Saclay, University of Edinburgh, Helmholtz-Zentrum Dresden-Rossendorf, and Peking University.

Collaboration and User Access

Access is coordinated via CERN user access procedures with proposals reviewed in processes similar to those for Large Hadron Collider experiments and smaller scale nuclear physics campaigns, involving peer review by panels including representatives from European Research Council funded projects and national funding agencies like NERC and DAE affiliates. The user community includes scientists from University of Oslo, Swansea University, University of Warsaw, University of York, and other institutions participating in consortiums such as ENSAR and FAIR preparatory collaborations. Training and safety induction are conducted with support from CERN user services and technical groups across ISOLDE.

Safety and Radiation Protection

Radiation protection and safety follow CERN radiological controls aligned with standards adopted by institutions including ICRP-influenced practices and national regulators like Swiss Federal Office of Public Health oversight. The station coordinates with the CERN Radiation Protection Group and accesses monitoring infrastructure similar to that used across other CERN facilities. Protocols for handling activated materials and target changes are informed by procedures developed with input from JRC laboratories, STFC-associated centers, and national radiation safety authorities. Waste management and decommissioning planning reference guidelines used by European Commission projects and national nuclear agencies.

Category:CERN experiments Category:Nuclear physics facilities