Beams Project Research Articles

Future facilities at PSI, the High-Intensity Muon Beams (HIMB) project

Currently, PSI delivers the most intense continuous muon beam in the world with up to a few 108 µ+/s. The High-Intensity Muon Beams (HIMB) project is developing a new target station and muon beamlines able to deliver 1010 µ+/s, with a huge impact for low-energy, high-precision muon experiments. While the next generation of proton drivers with beam powers in excess of the currently achieved 1.4 MW still require significant research and development, the focus of HIMB is to improve the surface muon yield with a new target geometry and to increase capture and transmission with a solenoid-based beamline in order to reach a total efficiency of approximately 10 %. We present the current status of the HIMB project.

Beamline design and optimisation for high intensity muon beams at PSI

The High Intensity Muon Beams (HIMB) project at the Paul Scherrer Institute (PSI) will provide muon intensities of the order of 1010 muons/s for particle physics and material science experiments, two orders of magnitude higher than the state of the art, which is currently available also at PSI. In particle transport simulations for the HIMB, we use G4beamline with measured + cross-sections and with variance reduction. We also use the codes COSY INFINITY, TRANSPORT, and TURTLE for some studies. We perform asynchronous Bayesian optimisation of the beamlines on a computing cluster using G4beamline and the optimisation package DeepHyper. We performed numerous studies for the design of the HIMB, and we produced various results, including the muon transmission, beam phase space, polarisation, and momentum spectrum.

The BeAMS project: Using inquiry and modeling to introduce students to the research process in an introductory geology laboratory

Students who enter introductory geology classes often have misconceptions about geoscience research, and they seldom have opportunities to gain authentic research experience in these classes. To improve student engagement in the class and understanding of geoscience research methods, a semester-long authentic inquiry research project was incorporated into an introductory geology laboratory class. This project requires students to create scientific models to test the hypotheses they generate, analyze data they collect and reflect on challenges they encounter. The utility of models in conducting geoscience research was emphasized, and student groups chose either visual models, computer models, or physical models for hypothesis testing. The impact of the project was assessed using pre-post surveys to determine changes in student understanding of research methods and student self-efficacy. Student reflections reveal qualitative improvements in both understanding and self-efficacy after project completion. Multiple-choice questions on research methods also support an improved understanding of research methods compared to a control semester. Statistically significant improvements in confidence to perform research-related tasks also demonstrate the value of the project. Completing this project helped students understand the scientific research process and how modeling is used in Earth science research. Implementing the project required significant instructor preparation and buy-in from graduate student teaching assistants (TAs), who acted as mentors to student research groups. Future iterations of this project will include additional conceptual scaffolding for students and increased support for TAs. Supplemental data for this article is available online at https://doi.org/10.1080/10899995.2021.1951080 .

Advances of the FRIB project

The Facility for Rare Isotope Beams (FRIB) Project has entered the phase of beam commissioning starting from the room-temperature front end and the superconducting linac segment of first 15 cryomodules. With the newly commissioned helium refrigeration system supplying 4.5[Formula: see text]K liquid helium to the quarter-wave resonators and solenoids, the FRIB accelerator team achieved the sectional key performance parameters as designed ahead of schedule accelerating heavy ion beams above 20[Formula: see text]MeV/u energy. Thus, FRIB accelerator becomes world’s highest-energy heavy ion linear accelerator. We also validated machine protection and personnel protection systems that will be crucial to the next phase of commissioning. FRIB is on track towards a national user facility at the power frontier with a beam power two orders of magnitude higher than operating heavy-ion facilities. This paper summarizes the status of accelerator design, technology development, construction, commissioning as well as path to operations and upgrades.

The ACCULINNA-2 project: The physics case and technical challenges

Implementing the Dubna Radioactive Ion Beams project (DRIBs) a new, efficient fragment separator ACCULINNA-2 was installed recently at the primary beam line of the U-400M cyclotron in the Flerov Laboratory of Nuclear Reactions, JINR. Since 2017, radioactive beams have been obtained from this facility. The motivation for the new RIB complex, together with an overview of the RIB research conducted in Dubna and its correlation with the worldwide RIB activities, are given in this paper. The status of the ACCULINNA-2 setup, the nearest prospects for completing its equipment, and the planned first-stage experiments are presented.

Production and release of ISOL beams from molten fluoride salt targets

In the framework of the Beta Beams project, a molten fluoride target has been proposed for the production of the required 101318Ne/s. The production and extraction of such rates are predicted to be possible on a circulating molten salt with 160MeV proton beams at close to 1MW power. As a most important step to validate the concept, a prototype has been designed and investigated at CERN-ISOLDE using a static target unit. The target material consisted of a binary fluoride system, NaF:LiF (39:61mol.%), with melting point at 649°C. The production of Ne beams has been monitored as a function of the target temperature and proton beam intensity. The prototype development and the results of the first online tests with 1.4GeV proton beam are presented in this paper.

Opportunities for neutrino experiments at ISOLDE

A molten salt target is currently proposed for the production of high rates of 18Ne required for the beta beams project. Intermediate proton energy beams at close to 1 MW power are used on a circulating molten NaF eutectic to produce and extract 1×1013 18Ne/s.A conceptual design of such a circulating loop is presented. The application of a molten salt target for the monitoring of noble gas production is discussed with respect to the planned experimental program, which will be used to validate the proposed concept. Furthermore, a systematic experimental study on the production and release of gaseous and volatile elements from molten sodium-based targets, in preparation at CERN-ISOLDE, is presented.

Temperature dependence of yields from multi-foil SPES target

The temperature dependence of neutron-rich isotope yields was studied within the framework of the HRIBF-SPES Radioactive Ion Beams (RIB) project. On-line release measurements of fission fragments from a uranium carbide target at \(\ensuremath 1600 {}^{\circ}\mathrm{C}\) , \(\ensuremath 1800 {}^{\circ}\mathrm{C}\) and \(\ensuremath 2000 {}^{\circ}\mathrm{C}\) were performed at ORNL (USA). The fission reactions were induced by a 40MeV proton beam accelerated into a uranium carbide target coupled to a plasma ion source. The experiments allowed for tests of performance of the SPES multi-foil target prototype loaded with seven UC2/graphite discs (ratio C/U = 4 with density about 4g/cm3.

Electron cyclotron resonance ion source DECRIS-4 for the U400 cyclotron

The electron cyclotron resonance ion source DECRIS-4 has been designed and constructed at the FLNR to be used as a second injector of heavy multiply charged ions for the U-400 cyclotron. After the modification of the injection side this source can be also used as a “charge breeder” (the “1+→n+” method) for the second phase of the Dubna radioactive ion beams project. The main feature of the ion source design is the creation of the extended resonance zone in a comparatively compact electron cyclotron resonance ion source. For this purpose the axial magnetic field is formed with a flat minimum. In this case the superposition of the axial magnetic field and the radial field of the permanent-magnet hexapole, made from NdFeB, allows one to create a larger resonance volume. For the plasma heating a microwave frequency of 14 GHz is used. In this paper we will present the basic design features of the ion source, including the results of the magnetic-field measurements. Some preliminary results of ion source tests are also reported.

Student engagement at minority‐serving institutions: Emerging lessons from the BEAMS project

AbstractThe authors examine the promises and prospects of using student engagement data to promote success at minority‐serving institutions.

The new ECR ion source DECRIS-4 (project)

A new ion source DECRIS-4 for the production of multiply charged ions is planned to be built at the JINR FLNR. The source can be used as an injector of heavy multiply charged ions for the U-400 cyclotron, as well as a “charge breeder” (the “1+→n+” method) for the second phase of the Dubna Radioactive Ion Beams project. The main feature of the ion source design is the creation of the extended resonance zone in a comparatively compact electron cyclotron resonance ion source. For this purpose the axial magnetic field distribution is formed with a flat minimum. Superposition of the axial magnetic field with the field of the permanent magnet hexapole, made from NdFeB, allows one to create a large resonance volume. In this case the electrons can be heated more efficiently. The maximum of the plasma density is situated near the axis, where ions are mainly extracted from. For the plasma heating a microwave frequency of 14 GHz will be used. A preliminary design of the source is described. Also the features and prospects for the application of this source are discussed.