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Radioactive Ion Beams (RIBs) of large intensity (10 6 pps or higher) are at the frontier in nuclear physics. We designed a novel detection system for RIBs diagnostics and tagging based on Silicon Carbide detectors and on custom frontend electronics ready to be coupled with a Real Data Management Unit. The full detection system is designed to measure the spatial distribution of the beam intensity and trajectory with sufficient spatial resolution (of the order of 1-2 mm). In addition, the detection system has to determine the RIB composition that can be obtained from the joint measurement of the energy loss (>E) of the ions passing through the sensors and the time of flight between two sensors or with respect to a given reference signal as the RadioFrequency signal of a Cyclotron. In this paper we present the full design of the proposed system together with the results of the first experimental qualification of the first mini-prototype. The paper also shows the steps towards the final detection system, housed in a DN160 spherical cross and able to cover an active area of 30 mm × 60 mm.

Thorium carbide (ThC2±x) nano-structured thin disc-like pellets were produced from thoria nanoparticles (ThO2-NP) and multi-walled carbon nanotubes (MWCNT). These composites are to be studied as a target material candidate for radioactive ion beam (RIB) production via nuclear reactions upon impact with high-energy proton beams on a stack of solid pellets. The ThO2-NP precursor was produced via precipitation of thorium oxalate from a thorium nitrate solution with oxalic acid and subsequent hydrothermal oxidation of the oxalate, creating the thoria nanoparticles. The ThO2-NP were then mixed with MWCNT in isopropyl alcohol and sonicated by two different methods to create a nanoparticle dispersion. This dispersion was then heated under medium vacuum to evaporate the solvent; the resulting powder was pressed into pellets and taken to an inert-atmosphere oven, where it was heated to 1650 °C and carbothermally reduced to ThC2±x. The resulting pellets were characterized via XRD, SEM-EDS, and Raman spectroscopy. The resulting thorium pellets exhibited, at most, trace levels of the oxide precursor. Furthermore, the nanotube structures were still present in the final product and are expected to contribute positively towards faster radioisotope release times by lowering isotope diffusion times, which is required for the efficient extraction of the shortest-lived (<1 s half-life) radioisotopes.

This review summarizes recent experimental progress in the structure and correlations of light neutron-rich nuclei. We first highlight achievements based on quasi-free scattering reactions in inverse kinematics at the Radioactive Isotope Beam Factory (RIBF), including investigations of the single-particle composition of halo systems—for example, revealing the minimal s-wave component in the “weak-halo” nucleus 17B—and the mapping of universal, surface-localized dineutron correlations in Borromean nuclei such as 11Li, 14Be and 17B. We then discuss recent advances in the study of multineutron correlations and cluster states, addressing both experimental challenges and major breakthroughs. These include the observation of a candidate 4n resonance, the absence of a resonant state in the 3n system, the characterization of direct two-neutron decay in 16Be, and evidence for a condensate-like α+n2+n2 cluster structure in the He8(02+) state. Finally, we discuss prospects for extending such investigations to heavier halo candidates and more complex multineutron systems, and outline the development of next-generation neutron detector arrays that will drive future progress in this field.

Developments at TRIUMF’s isotope separator and accelerator (ISAC) resonance ionization laser ion source (RILIS) in the past years have concentrated on increased reliability for on-line beam delivery of radioactive isotopes to experiments, as well as increasing the number of elements available through resonance ionization and searching for ionization schemes with improved efficiency. The current status of these developments is given with a list of two step laser ionization schemes implemented recently.

Highly porous yttrium oxide is fabricated as ion beam target material in order to produce radioactive ion beams via the Isotope Separation On Line (ISOL) method. Freeze casting allows the formation of an aligned pore structure in these target materials to improve the isotope release. Aqueous suspensions containing a solid loading of 10, 15, and 20 vol% were solidified with a unidirectional freeze-casting setup. The pore size and pore structure of the yttrium oxide freeze-casts are highly affected by the amount of solid loading. The porosity ranges from 72 to 84% and the crosslinking between the aligned channels increases with increasing solid loading. Thermal aging of the final target materials shows that an operation temperature of 1400 °C for 96 h has no significant effect on the microstructure. Thermo-mechanical calculation results, based on a FLUKA simulation, are compared to measured compressive strength and forecast the mechanical integrity of the target materials during operation. Even though they were developed for the particular purpose of the production of short-lived radioactive isotopes, the yttria freeze-cast scaffolds can serve multiple other purposes, such as catalyst support frameworks or high-temperature fume filters.

Particle therapy relies on the advantageous dose deposition which permits to highly conform the dose to the target and better spare the surrounding healthy tissues and organs at risk with respect to conventional radiotherapy. In the case of treatments with heavier ions (like carbon ions already clinically used), another advantage is the enhanced radiobiological effectiveness due to high linear energy transfer radiation. These particle therapy advantages are unfortunately not thoroughly exploited due to particle range uncertainties. The possibility to monitor the compliance between the ongoing and prescribed dose distribution is a crucial step toward new optimizations in treatment planning and adaptive therapy. The Positron Emission Tomography (PET) is an established quantitative 3D imaging technique for particle treatment verification and, among the isotopes used for PET imaging, the 11 C has gained more attention from the scientific and clinical communities for its application as new radioactive projectile for particle therapy. This is an interesting option clinically because of an enhanced imaging potential, without dosimetry drawbacks; technically, because the stable isotope 12 C is successfully already in use in clinics. The MEDICIS-Promed network led an initiative to study the possible technical solutions for the implementation of 11 C radioisotopes in an accelerator-based particle therapy center. We present here the result of this study, consisting in a Technical Design Report for a 11 C Treatment Facility. The clinical usefulness is reviewed based on existing experimental data, complemented by Monte Carlo simulations using the FLUKA code. The technical analysis starts from reviewing the layout and results of the facilities which produced 11 C beams in the past, for testing purposes. It then focuses on the elaboration of the feasible upgrades of an existing 12 C particle therapy center, to accommodate the production of 11 C beams for therapy. The analysis covers the options to produce the 11 C atoms in sufficient amounts (as required for therapy), to ionize them as required by the existing accelerator layouts, to accelerate and transport them to the irradiation rooms. The results of the analysis and the identified challenges define the possible implementation scenario and timeline.

We present an outlook of studies performed in collaboration or inspired by Prof. Mahir Hussein. The first part refers to the elastic scattering measurements performed in the 80–90 with α -structured systems with strong oscillations in the angular distributions and a large increase of the cross-sections at backward angles, an effect called Anomalous Large Angle Scattering (ALAS). The second part refers to the installation of the “Radioactive Ion Beams in BraSil” (RIBRAS) facility, which was an idea promoted by Prof. Hussein and became reality due to his strong support. It was installed in 2004 as the first radioactive ion beam facility in the southern hemisphere and it has been operating continuously since then. In this paper, we will describe the facility, and some interesting results obtained with the 2-neutron-halo, exotic 6 He beam, provided by RIBRAS.

Isotopes at the limits of nuclear existence are of great interest for their critical role in nuclear astrophysical reactions and their exotic structure. Experimentally, exotic nuclides are challenging to address due to their low production cross-sections, overwhelming amounts of contamination, and lifetimes of typically less than a second. To this end, a Multiple-Reflection Time-of-Flight mass spectrometer at the TITAN-TRIUMF facility was built to determine atomic masses. This device is the preferred tool to work with exotic nuclides due to its ability to resolve the species of interest from contamination and short measurement cycle times, enabling mass measurements of isotopes with millisecond half-lives. With a relative precision of the order 10−7, we demonstrate why the TITAN MR-TOF MS is the tool of choice for precision mass surveys for nuclear structure and astrophysics. The capabilities of the device are showcased in this work, including new mass measurements of short-lived tin isotopes (104–107Sn) approaching the proton dripline as well as 89Zr, 90Y, and 91Y. The last three illustrate how the broadband surveys of MR-TOF MS reach beyond the species of immediate interest.

Beams of short-lived radioactive nuclei are needed for frontier experimental research in nuclear structure, reactions, and astrophysics. Negatively charged radioactive ion beams have unique advantages and allow for the use of a tandem accelerator for post-acceleration, which can provide the highest beam quality and continuously variable energies. Negative ion beams can be obtained with high intensity and some unique beam purification techniques based on differences in electronegativity and chemical reactivity can be used to provide beams with high purity. This article describes the production of negative radioactive ion beams at the former holifield radioactive ion beam facility at Oak Ridge National Laboratory and at the CERN ISOLDE facility with emphasis on the development of the negative ion sources employed at these two facilities.

Tests of the unitarity of the Cabbibo-Kobayashi-Masakawa (CKM) matrix offer an important avenue for constraining the Standard Model of the electroweak interaction. Several methods are currently used to determine Vud, the largest element in the top-row normalization test. One such method is through the study of superallowed T = 1/2 mixed mirror transitions, which offers a complementary method to the current most-precise value that is determined from superallowed pure Fermi 0+ → 0+ transitions. The precision currently achievable by this method is currently limited by the very low number of transitions for which the Fermi-to-Gamow-Teller mixing ratio ρ has been measured. St. Benedict, the Superallowed Transition Beta-Neutrino Decay-Ion-Coincidence Trap, is currently under development at the University of Notre Dame’s Nuclear Science Laboratory, and intends to determine ρ for a range of new isotopes through measurements of the β-neutrino asymmetry parameter aβν using a linear Paul trap. In order to trap these ions, the fast, continuous secondary beam separated by the TwinSol twin solenoid separator must be thermalized and bunched. The system through which this will be done will feature a large-volume gas cell in which the ions will be thermalized, a double-RF-funnel-based ion guide system for the extraction of the ions, and a radiofrequency quadrupole (RFQ) to provide cooled ion bunches for capture in the Paul trap.