Experimental setups

Temporary experimental setups

The setups which come to ISOLDE for shorter periods are usually systems used for detection of specific decay modes of the studied nuclei. Some of them measure the gamma-rays and beta decay and strive to reconstruct the position of excited levels of the nucleus. Others use very fast gamma detectors which can say for how long different excited states live. There are setups which detect neutrons or protons, as well as alpha particles which are emitted in the decay of some nuclei. Also, systems to measure the millisecond to minute lifetime of different isotopes are used. The physics interest of these experiments spans from nuclear structure physics, through nuclear astrophysics, up to fundamental studies and applied science.

Fixed experimental setups

COLLAPS

COLLAPS

COLLAPS (COLlinear LAser sPectroScopy) stands at ISOLDE as a pioneering setup in the field of laser spectroscopy. This experiment focus on the measurement of distinctive nuclear properties of short-lived and exotic radioactive nuclei. These properties include nuclear spins, electromagnetic moments, and charge radii, which are extracted through the hyperfine structures and isotope shifts.

At the heart of COLLAPS's inquiry are fundamental questions about the nature of nuclear existence: What are the limits of nuclear existence? How do simple patterns emerge in complex nuclei? Are there new forms of structure far from stability? To address these questions, the COLLAPS team is dedicated to developing laser spectroscopy techniques of exceptional precision and sensitivity.

For more details about our recent results, the link to our publications is given here .

CRIS

CRIS

The CRIS (Collinear Resonance Ionization Spectroscopy) experiment at CERN ISOLDE combines the high resolution of collinear laser spectroscopy with the high efficiency and selectivity of resonant ionization. The experiment can be used for research in a variety of disciplines, such as the study of nuclear structures (through measurement of nuclear spins, moments and radii), the spectroscopy of radioactive atoms, ions and molecules, and opens future links to particle physics and astrophysics. It also allows the production of beams of high isomeric purity for dedicated decay spectroscopy studies, using a variety of detection set-ups.

For more details about the CRIS experiment and its partner institutions see http://isolde-cris.web.cern.ch/

EC-SLI

EC-SLI-GHM1

EC-SLI (Emission Channeling with Short-Lived Isotopes) is an experiment at ISOLDE dedicated to studying the lattice location of dopants and impurities in single crystals and epitaxial thin films. The main fields of work currently include semiconductor doping for applications in electronics and colour centers in diamond and related materials for quantum technologies, among others. While EC-SLI is the on-line setup for short-lived isotopes located at the GHM beam line, it is complemented by three off-line ones, also at ISOLDE, which are suitable for longer-lived isotopes with half-lives above a few hours.

ISOLDE Decay Station (IDS)

ISOLTRAP Decay Station

The ISOLDE Decay Station (IDS) is a permanent experiment at the ISOLDE facility dedicated to the decay properties of radioactive species of importance for nuclear structure, nuclear engineering and astrophysics. A variety of experimental systems can be coupled to the station for specialised decay studies, such as fast timing measurements of excited state lifetimes, proton and alpha particle emission, and neutron time of flight detectors for neutron energy spectroscopy. This makes the IDS an ideal tool for studying nuclear properties across the nuclear chart, from the lightest species that fragment into charged particles, to the beta-delayed fission of the heaviest nuclei.

ISOLDE Solenoidal Spectrometer (ISS)

The ISOLDE Solenoidal Spectrometer (ISS)

The ISOLDE Solenoidal Spectrometer (ISS) is used for precision studies of inelastic scattering and transfer reactions utilising the radioactive ion beams created in HIE-ISOLDE. The ISS is delivering a broad science programme addressing important topics in nuclear structure and nuclear astrophysics. The ISS has an advanced design that employs the proven HELIOS concept, whereby light charged particles emitted during the nuclear reactions are transported with high efficiency by the solenoidal magnetic field to an array of position-sensitive silicon detectors mounted on its axis. Measuring the particle energies and interaction positions in the silicon array allows the reaction Q-value to be determined without the problem of kinematic compression encountered in more conventional approaches. The ISS array comprises 24 double-sided silicon strip detectors with ASIC readout and is designed to allow Q-value resolutions approaching 20 keV to be achieved.

ISOLTRAP

ISOLTRAP

The ISOLTRAP experiment performs precision mass measurements on radioactive nuclei produced at ISOLDE employing different types of mass spectrometers and measurement techniques. Following the capture and cooling of the radioactive nuclei in a helium filled radiofrequency quadrupole trap an ion bunch can be studied in a multi reflection time-of-flight mass spectrometer where mass resolving powers exceeding 300000 are reached. This device is used for mass measurements of short-lived radionuclides but can also be used for the separation of a species of interest from a contaminated ion beam. Subsequently, the purified ion beam can be transferred to the Penning-traps where mass measurements with high precision can be performed by a measurement of the cyclotron frequency in a magnetic field. Here, relative uncertainties of 1E-8 and below are routinely reached.

LUCRECIA

LUCRECIA

Lucrecia is a Total Absorption gamma Spectrometer (TAS) located at the ISOLDE hall. It has been designed to measure feeding in beta decay through the detection of the gamma cascades following the decay. The b-feeding is one of the main ingredients in the calculation of the b-strength function, and is thus an essential element in the  proper estimation of the B(GT) or B(F). The use of the TAS technique is an alternative to high resolution gamma spectroscopy based on Ge detectors, which is affected by systematic errors due to the “Pandemonium effect” particularly for large Q-values.

MINIBALL

MINIBALL

The high-resolution Miniball germanium detector array has been operational at REX-ISOLDE at CERN for over 20 years. This array consists of 24 six-fold segmented, tapered, encapsulated high-purity germanium crystals and was specially designed for low multiplicity experiments with low-intensity radioactive ion beams (RIB). For work with rare-isotope beams, the multiplicities are low (often only a few states are excited) and the yields of such beams are usually much lower than for conventional experiments, so efficiency is paramount. High granularity and high efficiency were achieved by the segmentation of the charge-collection electrodes of the Ge detectors, giving a spatial resolution significantly finer than the dimensions of the crystal. The Miniball array has been used in numerous Coulomb-excitation and transfer-reaction experiments with exotic RIBs with energies up to around 10 MeV/u, produced at the ISOLDE facility.

MIRACLS

MIRACLS

The Multi Ion Reflection Apparatus for Collinear Laser Spectroscopy (MIRACLS) at ISOLDE aims to measure nuclear ground-state properties such as the size, shape and electromagnetic moments of rare radioactive isotopes. These properties are extracted from the measurements of the isotopes’ hyperfine structure using laser spectroscopy. MIRACLS’ goal is to increase the sensitivity of conventional, fluorescence-based collinear laser spectroscopy by confining the investigated ions in an ion trap. This novel scheme allows for the ions to be probed up to several thousands of times.

SEC

SEC

SEC (Scattering Experiments Chamber) at the XT03 Beamline of HIE-ISOLDE is an experimental station to facilitate diversified reaction experiments. The chamber is sufficiently big to accumulate a variety of charge particle detectors as well as scintillator detectors for gamma detection. It is equipped with a rotational disc of 50 cm radius radially graduated and supplied with Al-bars for precise support and positioning of detectors. A VME DAQ system with optical fiber readout of Si-detectors (320ch), together with a 16ch digitizer for scintillator detectors. This makes SEC a versatile station for reaction experiments to study low-lying resonances in light nuclei via transfer reactions.

VITO

VITO polarization line with end station for beta-detected NMR.

VITO (Versatile Ion polarisation Technique Online) is a permanent beamline at the ISOLDE facility devoted to a wide range of studies with laser-polarised radioactive beams. The setup for laser spin polarisation can be coupled to several end stations. These allow studies of the details of the weak force, properties of short-lived unstable nuclei, their role in nucleosynthesis, and even chemistry, biology, and material science.

WISArD

WISArD

The WISArD experiment has been set up for the investigation of the weak interaction focussing on the b-n angular correlation coefficient of 32Ar by looking at beta-delayed protons emitted from the daughter nucleus 32Cl. As the protons are emitted from a moving source, the proton energy distribution is thus subject to kinematical broadening and a kinematical shift.