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We report the charge-changing cross sections ( σ cc ) of 24 p -shell nuclides on both hydrogen and carbon at about 900 A MeV, of which 8,9Li, 10–12Be, 10,14,15B, 14,15,17–22N and 16O on hydrogen and 8,9Li on carbon are for the first time. Benefiting from the data set, we found a new and robust relationship between the scaling factor of the Glauber model calculations and the separation energies of the nuclei of interest on both targets. This allows us to deduce proton radii ( R p ) for the first time from the cross sections on hydrogen. Nearly identical R p values are deduced from both target data for the neutron-rich carbon isotopes; however, the R p from the hydrogen target is systematically smaller in the neutron-rich nitrogen isotopes. This calls for further experimental and theoretical investigations. [ABSTRACT FROM AUTHOR]

Monte Carlo simulations are widely used in nuclear physics to model experimental systems. In cases where there are significant unknown quantities, such as energies of states, an iterative process of simulating and fitting is often required to describe experimental data. We describe a Bayesian approach to fitting experimental data, designed for data from a 12Be(d,p) reaction measurement, using simulations made with GEANT4. Q-values from the 12C(d,p) reaction to well-known states in 13C are compared with simulations using BayesOpt. The energies of the states were not included in the simulation to reproduce the situation for 13Be where the states are poorly known. Both cases had low statistics and significant resolution broadening owing to large proton energy losses in the solid deuterium target. Excitation energies of the lowest three excited states in 13C were extracted to better than 90 keV, paving a way for extracting information on 13Be.

Resonant ionization laser ion sources (RILIS) provide a majority of the radioactive ion beams (RIB) at research facilities as they provide high ionization efficiencies coupled with element selective ionization. Recent developments at TRIUMF's RILIS are to develop improved ionization schemes using auto-ionizing resonances, improve efficiency and reliability of RILIS operation, and to meet the increased demands by experimenters for complex beam delivery modes. [ABSTRACT FROM AUTHOR]

The Beijing radioactive ion beam facility isotope separator on-line (BRISOL) is a radioactive ion beam facility based on a 100 MeV@200 μA proton cyclotron. The radioactive ion beams are produced by bombarding the thick target with proton beam provided by cyclotron. The mass resolving power of the BRISOL is better than 20 000. The first radioactive beams of 37K+ and 38K+ were generated at BRISOL with CaO targets in 2015, and the maximum current of the 38K+ beam is only 1×106 pps when the current of proton beam is 05 μA. The collinear laser spectroscopy experiments using 3743K+ beams will be carried out on BRISOL. The yields of 3743K+ would not be less than 1×106 pps in the experiment. In order to fulfill the requirements, it is necessary to increase the yield of radioactive ion beams. So a series of studies were carried out. The first step is the targets preparation. According to the requirements of the ISOL targets, CaO was selected as the targets material for the generation of radioactive ion beams. The CaO targets were prepared by cold pressing methods with Ca(OH)2, carboxymethyl cellulose (CMC) and deionized water. CMC was added as a binder and poreforming agent. Those materials were mixed in proportion and were cold pressed into desired shape. The thermal treatment was performed in a graphite furnace. After sintering, the targets were porous and then loaded into the targets container. The ion source with the ability of dual ionization mode, including surface ionization mode and FEBIAD ionization mode, was applied in the study. In order to improve the surface ionization efficiency for K, a 01 mm thick rhenium metal lining was installed on the inner wall of the cathode. Then an offline experiment was conducted and the spectra of CaO targets were measured. The experimental results show that Ca+ is ionized when the cathode current is high enough. Therefore, it is necessary to optimize the cathode currents for larger yield of K+. After that, an online experiment at BRISOL was carried out. The experiment results show that the 36.38,43,45.47K beams are produced successfully. The yield of 38K+ is increased to 1.12×1010 pps when the proton beam is 10 μA, the much larger yields are achieved through increasing proton intensities, optimizing both the structure of ion source and the targets working temperature. The development of CaO targets and the results of on-line experiment will be presented in this paper.

We have developed a gaseous Xe scintillator as a new Δ E detector which is expected to have good radiation hardness and fast response. In this research, we made a new version of the detector whose thickness is comparable to that of an ion chamber which is the current standard Δ E detector in RIBF. We carried out a performance test of the detector in RIBF. The root-mean-square (rms) resolutions of the atomic number Z around Z = 35 and Z = 55 are found to be about 0.2 and 0.3, respectively. In addition, it has a good timing resolution for a 238U beam of 74.4(6) ps in rms. [ABSTRACT FROM AUTHOR]

KoBRA can produce RI beams with energies of 5–10 MeV/u from stable ion beams (10–40 MeV/u) delivered from the superconducting linear accelerator SLC3 of RAON. In its early phase of operation, transfer reaction measurements with these RI beams can be performed for nuclear astrophysics studies. SNACK has been developed at RISP in order to measure the light ejectiles from the transfer reactions. With the beam trajectories obtained from upstream PPACs, excitation energy levels in the heavy recoils can be reconstructed by measuring light ejectile's energies and scattering angles. The expected results of transfer reaction measurements with SNACK and KoBRA beamline detectors were calculated by using a Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Monte Carlo simulations are widely used in nuclear physics to model experimental systems. In cases where there are significant unknown quantities, such as energies of states, an iterative process of simulating and fitting is often required to describe experimental data. We describe a Bayesian approach to fitting experimental data, designed for data from a 12Be(d,p) reaction measurement, using simulations made with GEANT4. Q-values from the 12C(d,p) reaction to well-known states in 13C are compared with simulations using BayesOpt. The energies of the states were not included in the simulation to reproduce the situation for 13Be where the states are poorly known. Both cases had low statistics and significant resolution broadening owing to large proton energy losses in the solid deuterium target. Excitation energies of the lowest three excited states in 13C were extracted to better than 90 keV, paving a way for extracting information on 13Be. [ABSTRACT FROM AUTHOR]

The CERN-MEDICIS facility aims to produce emerging medical radionuclides for the theranostics approach in nuclear medicine with mass separation of ion beams. To enhance the radioisotope yield and purity of collected samples, the resonance ionization laser ion source MELISSA was constructed, and provided the first laser ions at the facility in 2019. Several operational tests were accomplished to investigate its performance in preparation for the upcoming production of terbium radioisotopes, which are of particular interest for medical applications. [ABSTRACT FROM AUTHOR]

Porous silicon (PSi) nanoparticles are capable of delivering therapeutic payloads providing targeted delivery and sustained release of the payloads. In this work we describe the development and proof-of-concept in vivo evaluation of thermally hydrocarbonized porous silicon (PSi) nanoparticles that are implanted with radioactive 155Tb atoms and coated with red blood cell (RBC) membrane (155Tb-THCPSi). The developed nanocomposites can be utilized as an intravenous delivery platform for theranostic radionuclides. THCPSi thin films were implanted with 155Dy ions that decay to 155Tb at the ISOLDE radioactive ion-beam (RIB) facility at CERN. The films were processed to nanoparticles by ball-milling and sonication, and subsequently coated with either a solid lipid and RBC membrane or solely with RBC membrane. The nanocomposites were evaluated in vitro for stability and in vivo for circulation half-life and ex vivo for biodistribution in Balb/c mice. Nanoporous THCPSi films were successfully implanted with 155Tb and processed to coated nanoparticles. The in vitro stability of the particles in plasma and buffer solutions was not significantly different between the particle types, and therefore the RBC membrane coated particles with less laborious processing method were chosen for the biological evaluation. The RBC membrane coating enhanced significantly the blood half-life compared to bare THCPSi particles. In the ex vivo biodistribution study a pronounced accumulation to the spleen was found, with lower uptake in the liver and a minor uptake in the lung, gall bladder and bone marrow. We have demonstrated, using 155Tb RIB-implanted PSi nanoparticles coated with mouse RBC membranes, the feasibility of using such a theranostic nanosystem for the delivery of RIB based radionuclides with prolonged circulation time. For the first time, the RIB implantation technique has been utilized to produce PSi nanoparticle with a surface modified for better persistence in circulation. When optimized, these particles could be used in targeted radionuclide therapy with a combination of chemotherapeutic payload within the PSi structure. [ABSTRACT FROM AUTHOR]

A prototype ion source for RIB production in a reactor has been developed at China Institute of Atomic Energy to demonstrate the feasibility. The ion source has to be compact enough to fit into the neutron tunnel of the reactor. Also the ion source has to withstand the tens of kW heat from target fission. An electric heater is used to simulate the fission heat; at the same time the cathode of the ion source is heated to emit electrons which are energized between anode and cathode to ionize the fission product. The details of the ion source and its preliminary test results will be presented. [ABSTRACT FROM AUTHOR]

Various technologies for high current compact H– cyclotron have been developed since 1990s [1,2]. The energy of compact style machines was firstly elevated up to 100 MeV [3,4] for Radioactive Ion Beam production. The project, BRIF, Beijing Radioactive Ion-beam Facility was approved to start the construction in 2011, and the first proton beam was extracted from the 100 MeV compact cyclotron CYCIAE-100 on July 4, 2014. This paper will present the progress on the BRIF after the first proton beam, including the cyclotron improvements for the stable operation and beam intensity increasing, the RIB production and the implementation for mass resolution of 24,460, and the future development etc. [ABSTRACT FROM AUTHOR]

With the aim of increasing the primary beam intensity in the next generation Radioactive Ion Beam facilities, a major challenge is the production of targets capable of dissipating high beam power, particularly for molten targets. In that context, a direct molten loop target concept was proposed for short-lived isotopes for EURISOL. The circulation of molten metal enables the production of droplets enhancing the radioisotope diffusion. The concept also includes a heat exchanger ensuring thermal equilibrium under interaction with high proton beam power. A target prototype, named LIEBE, has been designed and assembled to validate this concept in the ISOLDE operation environment. The project is now in an offline commissioning phase in order to confirm the design specifications before tests under proton beam. Successful outcome of the project can lead to new beams with great interest in nuclear structure and physics studies. In particular, investigations fall short in the region around the double magic isotope 100 Sn at ISOL facilities because of the lack of a suitable primary beam driver and target-ion source unit for any of the present-day facilities. Achievable 100 Sn beam intensities and purities are calculated with ABRABLA and FLUKA considering the use of a high power molten lanthanum target combined with molecular tin formation and a FEBIAD ion source. The presented option takes into consideration upgrade scenarios of the primary beam at ISOLDE, going from a 1.4 GeV–2 μA to a 2 GeV–4 μA pulsed proton beam. [ABSTRACT FROM AUTHOR]

The Beijing Radioactive ion beam facility Isotope Separator On-Line (BRISOL) is a radioactive ion beam facility based on a 100 MeV cyclotron providing 200 μA proton beam bombarding the thick target to produce radioactive nuclei, which are transferred into an ion source to produce singly charged ion beams. In order to improve the ionization efficiency for alkali metals, an innovative ion source with the ability of dual ionization mode, including surface ionization mode and FEBIAD ionization mode, was developed. The design and results of this ion source will be presented in this paper. [ABSTRACT FROM AUTHOR]

Collinear laser spectroscopy (CLS) has been combined with the multi-reflection time-of-flight (MR-ToF) technique. To this end, a photodetection system has been implemented at the drift region of a MR-ToF apparatus and a laser beam has been sent along the path of the ions that are stored between the two ion-optical mirrors. The main goal of the present proof-of-principle (PoP) experiments, is the confirmation of the expected increase in sensitivity compared to conventional fluorescence-based CLS due to the repeated probing of the trapped ion bunches. The novel method will be used for the precise measurement of nuclear ground- and isomeric-state properties of exotic nuclei with low production yields at radioactive ion-beam facilities. A significant sensitivity improvement of CLS is expected, depending on the half-life and mass of the nuclide of interest. The status of the PoP setup and future improvements are discussed. [ABSTRACT FROM AUTHOR]

The multinucleon transfer (MNT) reaction is one promising way to produce neutron-rich heavy nuclei and even super heavy nuclei and attracts more and more attentions theoretically and experimentally. A low energy nuclear structure spectrometer called LENSHIAF specific to the MNT reactions will be designed and constructed in the ongoing big project HIAF in China. In the LENSHIAF spectrometer, the most challenge part is how to collect and stop efficiently the high-energy MNT products into the gas cell. By using Monte-Carlo method, the geometry of the gas cell, the thickness of the titanium window/degrader, and the optimal gas pressure filled in the gas cell have been calculated and estimated. For neutron-rich nuclei around N = 126 from 136Xe + 198Pt reaction, with a titanium window/degrader with a thickness of 2.5–3.5 μ m, a cylindrical helium gas cell with a length of 0.6 m and a diameter of 1.2 m can satisfy the requirements to stop the target-like fragments. For heavier and super heavy nuclei from 238U + 238U reaction, with a 5–8 μ m thick titanium window/degrader, the cylindrical gas cell has to be as big as a length of at least 1.6 m and a diameter of 1.6 m. [ABSTRACT FROM AUTHOR]

Abstract In typical nuclear physics experiments with radioactive ion beams (RIBs) selected by the in-flight separation technique, Si detectors or ionization chambers are usually equipped for the charge determination of RIBs. The obtained charge resolution relies on the performance of these detectors for energy loss determination, and this affects the particle identification capability of RIBs. We present an approach on improving the resolution of charge measurement for heavy ions by using the abundant energy loss information from different types of existing detectors along the beam line. Without altering the beam line and detectors, this approach can improve the charge resolution by more than 12% relative to the multiple sampling ionization chamber of the best resolution. [ABSTRACT FROM AUTHOR]

We have developed radio-frequency (RF) wire carpets and installed them in a cryogenic helium gas cell to increase the extraction yields of target-like fragments (TLFs) produced in multi-nucleon transfer (MNT) reactions at the KEK Isotope Separation System (KISS). KISS is an on-line isotope separator based on a gas cell system, and has been implemented for nuclear spectroscopy of isotopes approaching the N = 126 neutron shell closure below lead and neutron-rich actinides. We optimized the design of the RF wire carpet for efficient ion transport of TLFs from the simulations. We then performed experiments both off-line using rubidium ions from an alkali thermal ion-source in the gas cell, and on-line using TLFs produced by a 136Xe beam impinging upon a 198Pt target system, to confirm the performance expected of the design. We confirmed an increase in the extraction yields of more than an order of magnitude when using the cryogenic He gas cell with RF wire carpets as compared to our typical argon gas cell system with laser resonant ionization. The techniques and knowledge acquired in the development of these RF wire carpets will be applied to new RF wire carpets for use in a large-volume helium gas cell which will be installed at an upgraded KISS facility in the near future. [ABSTRACT FROM AUTHOR]

The 1–2 GeV proton induced spallation reaction on the high Z materials like Hg, or lead bismuth eutectic (LBE), popularly known as converter targets, will produce strong flux of fast neutrons which would further react with fissile materials to produce intense radioactive ion beam (RIB). LBE offers suitability for use as converters over Hg but it suffers from the demerit of radiotoxic polonium production. These targets may be viewed as a store house of clinically important and other exotic radionuclides. For application of those radionuclides, radiochemical separation from bulk target material is of utmost importance. [ABSTRACT FROM AUTHOR]

The GEM-TPC described herein will be part of the standard beam-diagnostics equipment of the Super-FRS. This chamber will provide tracking information for particle identification at rates up to 1 MHz on an event-by-event basis. The key requirements of operation for these chambers are: close to 100% tracking efficiency under conditions of high counting rate, spatial resolution below 1 mm and a superb large dynamic range covering projectiles from Z = 1 up to Z = 92 . The current prototype consists of two GEM-TPCs inside a single vessel, which are operating independently and have electrical drift fields in opposite directions. The twin configuration is done by flipping one of the GEM-TPCs on the middle plane with respect to the second one. In order to put this development in context, the evolution of previous prototypes will be described and its performances discussed. Finally, this chamber was tested at the University of Jyväskylä accelerator with proton projectiles and at GSI with Uranium, Xenon, fragments and Carbon beams. The results obtained have shown a position resolution between 120 to 300 μ m at moderate counting rate under conditions of full tracking efficiency. [ABSTRACT FROM AUTHOR]

TULIP (T arget Ion So u rce for Short- L ived I sotope P roduction) is an original Isotope Separator On Line project dedicated to the production of short-lived neutron-deficient ions. It was tested for the first time in March 2022 at GANIL (Grand Accélérateur National d'Ions Lourds)/ SPIRAL1 (Système de Production d'Ions Radioactifs Accélérés en Ligne, phase 1) with the production of Rb isotopes using a primary beam of 22Ne at an energy of 4.5 MeV/A. 76Rb and 78Rb isotope rates of ∼ 4 × 103 and ∼ 6 × 104 pps were measured for a primary beam intensity of 6 × 1012 pps and may be improved by a factor between 5 and 10. A remarkably short atom-to-ion transformation (AIT) time close to 200 μ s was achieved. This result demonstrates how beneficial the design of the TULIP target ion source system is in terms of response time and allows us to confidently look forward to 74Rb + production, which is one of the goals of the TULIP project. The results obtained on Rb production suggest testing the principle for the production of more sticky elements. Ions from metallic isotopes around 100Sn will be the next objective. • Response time breakthrough in an innovative fast ISOL system. • Improved ISOL efficiency limits with respect to radioactive decay. • A new ISOL method for the production of neutron-deficient short-lived isotopes. [ABSTRACT FROM AUTHOR]

One of the experimental programs that will be carried out at the Extreme Light Infrastructure – Nuclear Physics (ELI-NP) facility is the production of exotic neutron-rich ion beams in an IGISOL facility via photofission in a stack of actinide targets placed at the center of a cell filled with He gas. Simulations with the Geant4 toolkit were done for the optimization of the target configuration that maximizes the rate of released photofission fragments. The cell geometry is established based on the stopping properties of these fragments. Studies, based on simulations with Geant4 and SIMION 8.1, of the space charge effect and its induced electric field in the gas cell are presented. Estimates of the extraction time and efficiency of the photofission fragments are derived. [ABSTRACT FROM AUTHOR]

The FEBIAD ion source is routinely operated at TRIUMF-ISAC to produce radioactive ion beams, however there is scope to improve the ionization efficiency and beam quality. To achieve this improvement, simulations with the Comsol multiphysics software suite and experimental studies are being performed. Preliminary simulations indicate that the ionization rate inside the anode exhibits a spatial variation determined by the local electron fluence. The FEBIAD electromagnet coil is included in a simulation for the first time and a first validation of the methodology is the reproduction of experimental observables, e.g. the ion current generated as a function of the electromagnet coil current. The multiphysics approach of the simulations, and the experimental validation, can lead to a better understanding with possibilities to optimize the FEBIAD ion source and improve its versatility. With ARIEL, TRIUMF's new ISOL facility, two target stations with improved target-ion source flexibility will open additional avenues to implement modified designs of a FEBIAD with increased capabilities. [ABSTRACT FROM AUTHOR]

The Extreme Light Infrastructure – Nuclear Physics (ELI-NP) laboratory in Bucharest, Romania, will host an IGISOL-type facility which will study exotic neutron-rich ion beams produced via photo-fission in actinide targets placed at the center of a cryogenic gas cell. Using a complex radio frequency quadrupole for radioactive ion beam formation, a powerful multiple-reflection time-of-flight mass spectrometer for selecting the refractory isotopes of interest, and several measurement stations, this facility will be an exciting new tool for nuclear scientists. The two mechanisms of ion transport inside the gas cell, namely drift by electric fields and drag by supersonic gas jets, are studied. A program to test the individual components of the stopping cell is discussed. [ABSTRACT FROM AUTHOR]

The Resonance Ionization Laser Ion Source (RILIS) has emerged as an important technique in many Radioactive Ion Beam (RIB) facilities for its reliability, and ability to ionize target elements efficiently and element selectively. GISELE is an off-line RILIS test bench to study the implementation of an on-line laser ion source at the GANIL separator facility. The aim of this project is to determine the best technical solution which combines high selectivity and ionization efficiency with small ion beam emittance and stable long term operation. The ion source geometry was tested in several configurations in order to find a solution with optimal ionization efficiency and beam emittance. Furthermore, a low work function material was tested to reduce the contaminants and molecular sidebands generated inside the ion source. First results with ZrC ionizer tubes will be presented. Furthermore, a method to measure the energy distribution of the ion beam as a function of the time of flight will be discussed. [ABSTRACT FROM AUTHOR]

The Beijing Radioactive ion beam facility Isotope Separator On-Line (BRISOL) is a radioactive ion beam facility based on a 100 MeV cyclotron providing 100 μA proton beam bombarding a thick target to produce radioactive nuclei, which are transferred into an ion source to produce a singly-charged ion beam. The construction and installation of BRISOL was completed in March 2014. The commissioning of the BRISOL facility with stable beams has been carried out in the last year. The ion source, the separator and the beam-line were tested with a 39 K + stable beam. The tests and the current status of the BRISOL facility will be presented in this paper. [ABSTRACT FROM AUTHOR]

The efficient and rapid production of a high-quality, pure beam of highly charged ions is at the heart of any radioactive ion beam facility. Whether an electron cyclotron resonance (ECR) ion source or an electron beam ion source (EBIS) is used to produce these highly charged ions, their operating characteristics will set the boundaries on the range of experiments which can be performed. In addition, time structure and duty cycle have to be considered when defining the operating parameters of the accelerator system as a whole. At Argonne National Laboratory (ANL), an ECR charge breeder was developed as part of the Californium Rare Ion Breeder Upgrade (CARIBU) program. The charge breeding efficiency and high charge state production of the source is at the forefront of ECR charge breeders, but its overall performance as part of the accelerator system is limited by pervasive background and relatively long breeding times. As such, an EBIS charge breeder has been developed and is running in an off-line configuration. It has already demonstrated good breeding efficiencies, shorter residence times, and reduced background and is scheduled to replace the ECR charge breeder in late 2015. The resultant change in duty cycle and time structure necessitates changes to the overall operation of the facility. The experiences with these breeders, as well as from several other facilities which already utilize an ECR or EBIS for charge breeding, help to define the operational characteristics of each technology – their strengths, their weaknesses, and the possible paths to improvement. [ABSTRACT FROM AUTHOR]

Hadron therapy was first proposed in 1946 and is by now widespread throughout the world, as witnessed with the design and construction of the CNAO, HIT, PROSCAN and MedAustron treatment centres, among others. The clinical interest in hadron therapy lies in the fact that it delivers precision treatment of tumours, exploiting the characteristic shape (the Bragg peak) of the energy deposition in the tissues for charged hadrons. In particular, carbon ion therapy is found to be biologically more effective, with respect to protons, on certain types of tumours. Following an approach tested at NIRS in Japan [1], carbon ion therapy treatments based on 12 C could be combined or fully replaced with 11 C PET radioactive ions post-accelerated to the same energy. This approach allows providing a beam for treatment and, at the same time, to collect information on the 3D distributions of the implanted ions by PET imaging. The production of 11 C ion beams can be performed using two methods. A first one is based on the production using compact PET cyclotrons with 10–20 MeV protons via 14 N(p, α ) 11 C reactions following an approach developed at the Lawrence Berkeley National Laboratory [2]. A second route exploits spallation reactions 19 F(p,X) 11 C and 23 Na(p,X) 11 C on a molten fluoride salt target using the ISOL (isotope separation on-line) technique [3]. This approach can be seriously envisaged at CERN-ISOLDE following recent progresses made on 11 C + production [4] and proven post-acceleration of pure 10 C 3/6+ beams in the REX-ISOLDE linac [5]. Part of the required components is operational in radioactive ion beam facilities or commercial medical PET cyclotrons. The driver could be a 70 MeV, 1.2 mA proton commercial cyclotron, which would lead to 8.1 × 10 7 11 C 6+ per spill. This intensity is appropriate using 11 C ions alone for both imaging and treatment. Here we report on the ongoing feasibility studies of such approach, using the Monte Carlo particle transport code FLUKA [6,7] to simulate pristine Bragg Peaks of 11 C, in order to compare its performance with 12 C, in the context of hadron therapy. [ABSTRACT FROM AUTHOR]

SPIRAL1 facility is currently under transformation (Dubois) [1] in order to extend the range of radioactive ion beam offered to users. It will be able to host a larger variety of target ion source systems by the end of 2016, needed to fulfil the production requirements related to the chemical variety of the isotopes demanded by the physicists. The extent of the transformation is limited by the frame of the safety regulation and by the existing facility. Several combinations of mono-charged or multi-charged ECR, FEBIAD and surface ionization sources with new target materials are becoming possible. Some of these combinations are already under test. A comparison between expected SPIRAL1 performances and results obtained in other facilities is presented with the aim of leading our next developments. [ABSTRACT FROM AUTHOR]

The determination of the electron neutrino mass by calorimetric measurement of the 163 Ho electron capture spectrum requires ultra-pure samples. Several collaborations, like ECHo or HOLMES, intend to employ microcalorimeters into which 163 Ho is implanted as an ion beam. This makes a selective and additionally very efficient ion source for holmium mandatory. For this purpose, laser resonance ionization of stable holmium 165 Ho was studied, using a three step excitation scheme driven by pulsed Ti:sapphire lasers. Five measurements with sample sizes of 10 14 and 10 15 atoms were performed for the efficiency investigation. In average, an excellent ionization efficiency of 32(5) % could be shown, demonstrating the suitability for ion beam implantation. [ABSTRACT FROM AUTHOR]

We report on the conception and first tests of the General Purpose Ion Buncher (GPIB), the radio-frequency beam-cooler and buncher that will supply the DESIR (Decay, Excitation and Storage of Radioactive Ions) experimental hall to be constructed to complement the SPIRAL1 and SPIRAL2 facilities in GANIL. Its goals are both to reduce the emittance and if necessary to bunch the radioactive ion beam from the GANIL production facilities to adapt it to the needs of the different experimental setups in the DESIR hall. The mechanical design is similar to the existing ISCOOL quadrupole at ISOLDE but the new radio-frequency system enables a much stronger radial confinement. The GPIB is developed at LP2i Bordeaux 1 1 LP2i Bordeaux was known as Centre d'Études Nucléaires de Bordeaux-Gradignan (CENBG) before the name was changed in 2022. in parallel with the PIPERADE double Penning trap and a beamline has been constructed there to characterize both. The cooling of a 30 keV beam to an emittance of 3 π mm mrad and a transmission above 80% in continuous mode is demonstrated for currents up to a few nA. Some first results concerning the bunching mode are also shown though this mode is still under development. [ABSTRACT FROM AUTHOR]

High intensity 11 C beams are necessary for the investigation of the formation of 12 C via the nuclear reaction 11 C(p, γ ) 12 N → 12 C + e + + ν . The production of intense carbon beams on-line is quite challenging due to the thermodynamic properties and chemical reactivity of carbon at high temperatures. A previous attempt, using a medical isotope cyclotron production method in batch mode, was not conclusive. The intensity obtained was at least one order of magnitude too low for a direct proton capture experiment using the DRAGON facility at ISAC/TRIUMF. Producing a 11 C beams using the ISOL method requires a target capable of efficiently releasing the carbon isotopes. NiO has been selected as a target material because most of the nickel carbides are not stable at high temperature. The development of carbon beams using a composite NiO/Ni target on-line is described. [ABSTRACT FROM AUTHOR]

The time-of-flight (TOF) system is available at the ISAC rare isotope facility to measure the energy of stable and radioactive ion beams in the range of 0.5–22 Mev/u. The system, comprised of three secondary electron emission based monitors, is operated with practically all available beam intensities starting from as low as 10 3 ions per second. Recently the system was equipped with the calibration setup based on a 266 nm ultraviolet laser. Laser light interacting with the TOF monitors generates secondary electrons due to the photoelectric effect and acts as a reference beam traveling at a well- known velocity. After calibration, accuracy of energy measurements improved to be better than 0.1%. [ABSTRACT FROM AUTHOR]

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.