The next generation of experiments on charged lepton flavor violation demands higher muon rates. To achieve this, one of the existing target stations at the Paul Scherrer Institute's high-intensity proton accelerator, along with its two connected beamlines, will be dismantled and rebuilt as part of the High Intensity Muon Beams (HIMB) project, under the Swiss Roadmap for Research Infrastructures initiative, IMPACT. The new MuH2 and MuH3 beamlines will rely on 15 large-aperture solenoids and 5 dipoles for muon beam transport, designed to handle a large phase-space beam. Our estimates of the absorbed dose levels indicate that five transport solenoids and two dipoles must be radiation-resistant, requiring the use of mineral-insulated cables, whilst the other magnets can utilize epoxy-impregnated coils. Currently, the design of transport beamline components is based on standard resistive magnets, which suffer from high power consumption. This study aims to explore an alternative using Nb-Ti superconducting coils to reduce power consumption. The paper focuses on the design study of transport solenoids and includes a thermo-economic analysis, considering radiation exposure at three positions relative to the target.

The Isotope and Muon Production using Advanced-Cyclotron and Target Technology Project (IMPACT) foresees the introduction of two new target stations and three new beamlines: one for radionuclide production and two for surface muon production. The latter forms the project, High-Intensity Muon Beams (HIMB), which plans to increase the muon rate from the current world record of 10(8) mu(+)/s up to 10(10) mu(+)/s. This work presents an overview of the future HIMB beamlines focusing on the magnet designs that have been developed to ensure increased muon rate production and transmission. Specific radiation-hard resistive coils, based on mineral insulation, are required in this case due to the proximity to the target station. A high muon capture and transmission efficiency requires solenoid-like magnets, as well as dipole magnets and crossed-field separators to select the desired particles, while suppressing unwanted background particles. The radiation-hard capture solenoid plays the most important role in the whole beamline since it must provide a high capture efficiency. Beam optics studies provided the on-axis field profile necessary for optimizing the size and shape of the capture solenoid. Therefore, the article will also elucidate on these solenoid design strategies for achieving the desired capture efficiency.

IMPACT (Isotope and Muon Production with Advanced Cyclotron and Target Technologies) is a proposed initiative envisaged for the high-intensity proton accelerator facility (HIPA) at the Paul Scherrer Institute (PSI). As part of IMPACT, a radioisotope target station, TATTOOS (Targeted Alpha Tumour Therapy and Other Oncological Solutions) will allow the production of terbium radionuclides for therapeutic and diagnostic purposes. The proposed TATTOOS beamline and target will be located near the UCN (Ultra Cold Neutron source) target area, branching off from the main UCN beamline. In particular, the beamline is intended to operate at a beam intensity of 100 μA, requiring a continuous splitting of the main beam via an electrostatic splitter. Realistic beam loss simulations to verify safe operation have been performed and optimised using Beam Delivery Simulation (BDSIM), a Geant4 based tool enabling the simulation of beam transportation through magnets and particle passage through the accelerator. In this study, beam profiles, beam transmission and power deposits are generated and studied.

The High Intensity Proton Accelerator (HIPA) cyclotron at the Paul Scherrer Institut (PSI) delivers 590 MeV CW proton beam with a maximum power of 1.42 MW. After extraction, the beam is transferred in a 120 m long channel towards two target stations (TgM and TgE) for surface muon production before depositing its remaining power at the spallation target SINQ for neutron production. As part of the High Intensity Muon Beamline (HIMB) feasibility study, the first of these targets will be replaced with a thicker one thereby increasing the rate of surface muon production. However, a key challenge for HIMB is to maintain the proton beam losses to the lowest possible levels which requires improving our understanding of the distributed losses along the MW-class beamline. To this end, a new approach was developed where the aim is to relate the experimental values of the temperature, beam profile measurements as well as beam current measurements to the combined power deposition calculations and primary beam losses using Monte Carlo simulation tools.

Fluorescence Nuclear Track Detectors (FNTDs) are part of a new technology developed for particle detection and applicable to personal neutron dosimetry. The objective of this study is to simulate the FNTD fast neutron response to: (i) assess and understand the performance of the existing neutron dosimeter design (Landauer Inc.) and its associated single layer track-spots analysis; and (ii) evaluate the potential information that can be obtained by the analysis of the 3D reconstructed recoil proton trajectories. To achieve that, a FLUKA Monte Carlo (MC) model of the current FNTD design was developed and the FNTD response was investigated for mono-energetic neutrons and the 252Cf and 241AmBe neutron sources. The investigation of the recoil proton densities behind the different converters showed that the single layer analysis and dose calculation algorithm, based on the comparison and subtraction of the track densities behind the different converters, works properly only up to neutron energies ~13 MeV. Above this neutron energies, recoil protons generated in the detector housing (PE) have a range larger than the thickness of the PTFE and 6Li-enriched glass, reaching the FTND and, therefore, adding to the signal in these detection regions and influencing the secondary electron discrimination and the energy determination algorithm. MC simulations show that the FNTD 3D reconstructed recoil proton tracks can provide estimates of the irradiation angles and average neutron energy. The results show that the angle or displacement (dX/dZ or dY/dZ) distributions of the recoil proton tracks can be used to obtain information on irradiation angle; the angle with the detector's normal (polar angle), the most important because of its influences on the FTND sensitivity, can be determined in laboratory and for irradiation angles < 60° with an 4° uncertainty already for doses > 4.5 mSv in the case of a214AmBe neutron irradiation. The neutron field mean energy can also be determined for normal irradiation by analysing the depth distribution of the recoil proton tracks already for a minimum of 150 tracks, or 2.5 mSv for 241AmBe, assuming a scanned area is ~2.0 mm2. Therefore, the present study contributes to understanding the performance of the current FNTD design and analysis for neutron dosimetry and investigates a new detector evaluation approach to gain additional information on the irradiation conditions.

Inclusive electron scattering from nuclear targets has been measured to extract the nuclear dependence of the inelastic cross section in Hall C at the Thomas Jefferson National Accelerator facility. Results are presented for 2H, 3He, 4He, 9B, 12C, 63Cu and 197Au at an incident electron beam energy of 5.77 GeV for a range of momentum transfer from Q^2 = 2 to 7 (GeV/c)^2. These data improve the precision of the existing measurements of the EMC effect in the nuclear targets at large x, and allow for more detailed examinations of the A dependence of the EMC effect.

J. Arrington, 2 J. Bane, 4 A. Daniel, 6 N. Fomin, 4, 6 D. Gaskell, J. Seely, R. Asaturyan, ∗ F. Benmokhtar, W. Boeglin, P. Bosted, M.H.S. Bukhari, M.E. Christy, S. Connell, † M.M. Dalton, 8 D. Day, J. Dunne, D. Dutta, 15 L. El Fassi, R. Ent, H. Fenker, H. Gao, 15 R.J. Holt, T. Horn, 8, 16 E. Hungerford, M.K. Jones, J. Jourdan, N. Kalantarians, C.E. Keppel, 13 D. Kiselev, ‡ A.F. Lung, S. Malace, D.G. Meekins, T. Mertens, H. Mkrtchyan, G. Niculescu, I. Niculescu, D.H. Potterveld, C. Perdrisat, V. Punjabi, X. Qian, P.E. Reimer, J. Roche, V.M. Rodriguez, O. Rondon, E. Schulte, K. Slifer, G.R. Smith, P. Solvignon, ∗ V. Tadevosyan, L. Tang, 13 G. Testa, R. Trojer, V. Tvaskis, F.R. Wesselmann, S.A. Wood, L. Yuan, and X. Zheng 6 Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Argonne National Laboratory, Lemont, Illinois 60439, USA University of Massachusetts, Amherst, Massachusetts 01003, USA University of Tennessee, Knoxville, Tennessee 37966, USA University of Houston, Houston, Texas 77044, USA University of Virginia, Charlottesville, Virginia 22904, USA Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute), 02 Alikhanyan Brothers Str., Yerevan 0036, Armenia University of Maryland, College Park, Maryland 20742, USA Florida International University, Miami, Florida 33199, USA Hampton University, Hampton, Virginia 23669, USA Mississippi State University, Mississippi State, Mississippi 39762, USA Triangle Universities Nuclear Laboratory, Duke University, Durham, North Carolina 27710, USA Catholic University of America, Washington, DC 20064, USA Basel University, Basel, Switzerland James Madison University, Harrisonburg, Virginia 22807, USA College of William and Mary, Wiliamsburg, Virginia, 23185, USA Norfolk State University, Norfolk, Virginia 23529, USA (Dated: October 19, 2021)

The creating of nanopore ensemble in a polymethylmethacrylate (PMMA) film using swift heavy ion irradiation was studied. The pores are formed in the PMMA film by irradiation with Xe ion with energy of 167 MeV and the subsequent etching. Atomic force microscopy revealed that the created pore diameters was in the range of 50-100 nm and the depths in the range 2060 nm. The resulting pores might be filled with different materials and used in various areas of micro- and nanoelectronics.

Changing the configuration of the cold neutron source during a planned extended shutdown of the Swiss Spallation Neutron Source (SINQ) is being considered for improving performance of instruments at SINQ that use cold neutrons. The cold neutron source consists of a 20 L volume of liquid D-2 at approximately 25 K. This study includes making the re-entrant hole external, redesigning the re-entrant hole geometry, adding a Pb-208 reflector, replacing the zirconium safety hulls, adding cryogenic beryllium reflector/filters, and incorporating an active ortho-D-2 conversion loop. The optimization methods and the effects of the best-case modifications at all six neutron guides are presented. The best case design is predicted to yield a maximum gain factor of 1.5 in cold neutron intensity.

The results of numerical simulations of multipacting discharge in a superconducting accelerating Crossbar H-type (CH) cavity are presented in this paper. The localization of multipactor trajectories in the 15-gap 217 MHz superconducting (sc) CH cavity at various levels of accelerating voltage is considered.

Real-time monitoring of individual particles from atmospheric aerosols was performed by means of a specifically developed single-particle fluorescence spectrometer (SPFS). The observed fluorescence was assigned to particles bearing polycyclic aromatic hydrocarbons (PAH). This assignment was supported by an intercomparison with classical speciation on filters followed by gas chromatography-mass spectrometry (GC-MS) analysis. As compared with daily averaged data, our time-resolved approach provided information about the physicochemical dynamics of the particles. In particular, distinctions were made between background emissions related to heating, and traffic peaks during rush hours. Also, the evolution of the peak fluorescence wavelength provided an indication of the aging of the particles during the day.

The influence of aerosols on climate is highly dependent on the particle size distribution, concentration, and composition. In particular, the latter influences their ability to act as cloud condensation nuclei, whereby they impact cloud coverage and precipitation. Here, we simultaneously measured the concentration of aerosols from sea spray over the North Atlantic on board the exhaust-free solar-powered vessel "PlanetSolar", and the sea surface physico-chemical parameters. We identified organic-bearing particles based on individual particle fluorescence spectra. Organic-bearing aerosols display specific spatio-temporal distributions as compared to total aerosols. We propose an empirical parameterization of the organic-bearing particle concentration, with a dependence on water salinity and sea-surface temperature only. We also show that a very rich mixture of organic aerosols is emitted from the sea surface. Such data will certainly contribute to providing further insight into the influence of aerosols on cloud formation, and be used as input for the improved modeling of aerosols and their role in global climate processes.

Large amounts of 10Be are produced at the PSI muon production facility by high-energy proton spallation in polycrystalline graphite. For the extraction of 10Be out of large amounts of carbon, pyrolysis followed by chemical purification has been performed. Approx. 270g of graphite from Target E92, which had received a total proton charge of 29 Ah between 2002 and 2005, have been burned at 1000°C in a stream of oxygen. The volatile radioactive oxidation product 3H2O was trapped in 3 water bubblers connected in series. The remainder, a white hygroscopic solid material mainly consisting of 7Li2O, 9/10BeO and 10/11B2O3, was dissolved in HF and subsequently purified by ion exchange chromatography. Radioactive impurities such as 22Na, 44Ti, 54Mn, 60Co, 101Rh, 133Ba and 172Hf have been separated from the final product. The purified material represents a mixture of approx. 6.5mg 9Be and 3.5mg (3.3MBq) 10Be. It is ready to be used for scientific investigations requiring large amounts of this precious isotope.

Changing the configuration of the cold neutron source during an extended shutdown of the Swiss Spallation Neutron Source (SINQ) at the Paul Scherrer Institut is being considered for improving performance of the instruments that use the cold source. Proposed plans include making the REH external (ensuring that it is not filled with liquid D2) and using a REH that has been optimized to provide maximum gains between 3 and 6 Å. The optimization study was done using the MCNP Monte Carlo particle transport code, but was made tenable by developing a quick flux reconstruction technique that allows the neutron guide reflectivity to be approximated and accounted for in the optimization figure of merit. Ultimately, a wedgeshaped REH that penetrates the D2 volume to about 4 cm from its center was determined to be optimal, and should provide an average gain of 24% from 3 and 6 Å and a peak gain of 29% at 5.5.

The results of tests on samples of foam concrete with a hardening accelerator are presented. As the setting and hardening accelerators the following chemical additives were used: Universal-P-2 and Asilin 12. All additives were added into the insulating foam concrete mix of brand D 400 in the amount of 0.5% to 1% of cement weight. By using of additives in foam concrete technology - hardening accelerators Asilin 12 and Universal P2 in the amount of 0.5 % - and 1.0% by weight of cement foam concrete structure formation is accelerated and increases strength by 60%. For the industrial preparation of foam concrete mix technological regulations are worked out, in which it is recommended to use additives -hardening accelerators Asilin 12 in the amount of 0.5% and Universal P2 - 1% of cement weight.

The Paul Scherrer Institut operates two meson graphite targets, Target M and Target E, for creating the world’s most intense pion and muon beams by using 590 MeV protons and c.w. beam currents of up to 2.4 mA (=1.4 MW). The energy deposit on Target E is 20 kW mA −1 . The proton beam feeds also the spallation neutron source SINQ, which operates in DC mode and produces thermal and cold neutrons. The SINQ target consists of a bundle of lead filled Zircaloy tubes. In this report the continuous developments of both target facilities and their operation are presented.