Explore the vast range of titles available.

All papers published in this volume have been reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.• Type of peer review: Single Anonymous• Conference submission management system: Morressier• Number of submissions received: 63• Number of submissions sent for review: 62• Number of submissions accepted: 61• Acceptance Rate (Submissions Accepted / Submissions Received × 100): 96.8• Average number of reviews per paper: 1.02• Total number of reviewers involved: 32• Contact person for queries:Name: Francis PrattEmail: francis.pratt@stfc.ac.ukAffiliation: Science and Technology Facilities Council - ISIS Muons

The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About 10 11 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to ( 3.27 ± 0.07 ) × 10 11 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill.

Most μ SR is done with the μ + because 100% polarized surface muons have a fixed lifetime and usually retain their full polarization upon stopping in the sample, whereas the μ − often has higher energy, loses most of its polarization through LS coupling during its cascade to the ground state of the muonic atom, and is then vulnerable to μ − p → nν μ in the nucleus, so its lifetime depends on the nucleus and is often very short. However, μ − SR offers unique information of various kinds and is often essential. I will describe some ‘tricks’ that might make μ − SR more practical – some of which (like looking at nonzero-spin nuclei) are well-established, and some of which are more speculative (like measuring the energies of muonic X-rays to select events following a specific transition).

The use of accelerated beams of electrons, protons or ions has furthered the development of nearly every scientific discipline. However, high-energy muon beams of equivalent quality have not yet been delivered. Muon beams can be created through the decay of pions produced by the interaction of a proton beam with a target. Such ‘tertiary’ beams have much lower brightness than those created by accelerating electrons, protons or ions. High-brightness muon beams comparable to those produced by state-of-the-art electron, proton and ion accelerators could facilitate the study of lepton–antilepton collisions at extremely high energies and provide well characterized neutrino beams 1 – 6 . Such muon beams could be realized using ionization cooling, which has been proposed to increase muon-beam brightness 7 , 8 . Here we report the realization of ionization cooling, which was confirmed by the observation of an increased number of low-amplitude muons after passage of the muon beam through an absorber, as well as an increase in the corresponding phase-space density. The simulated performance of the ionization cooling system is consistent with the measured data, validating designs of the ionization cooling channel in which the cooling process is repeated to produce a substantial cooling effect 9 – 11 . The results presented here are an important step towards achieving the muon-beam quality required to search for phenomena at energy scales beyond the reach of the Large Hadron Collider at a facility of equivalent or reduced footprint 6 . Ionization cooling, a technique that delivers high-brightness muon beams for the study of phenomena at energy scales beyond those of the Large Hadron Collider, is demonstrated by the Muon Ionization Cooling Experiment.

Heritage Science HS spans a large variety of objects and materials, as well as anything that has historic, artistic, anthropological, and natural significance. This paper aims to bridge the gap between the physical and natural sciences and the humanities, and divulge neutron imaging techniques to a wider community. Here we give an introduction of the neutron imaging capabilities at the ISIS Neutron and Muon Source (UK), and a brief overview of some research activities in HS carried out at the facility in recent years, from neutron tomography to elemental imaging.

The central challenge in building a quantum computer is error correction. Unlike classical bits, which are susceptible to only one type of error, quantum bits (qubits) are susceptible to two types of error, corresponding to flips of the qubit state about the X and Z  directions. Although the Heisenberg uncertainty principle precludes simultaneous monitoring of X - and Z -flips on a single qubit, it is possible to encode quantum information in large arrays of entangled qubits that enable accurate monitoring of all errors in the system, provided that the error rate is low 1 . Another crucial requirement is that errors cannot be correlated. Here we characterize a superconducting multiqubit circuit and find that charge noise in the chip is highly correlated on a length scale over 600 micrometres; moreover, discrete charge jumps are accompanied by a strong transient reduction of qubit energy relaxation time across the millimetre-scale chip. The resulting correlated errors are explained in terms of the charging event and phonon-mediated quasiparticle generation associated with absorption of γ-rays and cosmic-ray muons in the qubit substrate. Robust quantum error correction will require the development of mitigation strategies to protect multiqubit arrays from correlated errors due to particle impacts. Cosmic-ray particles and γ-rays striking superconducting circuits can generate qubit errors that are spatially correlated across several millimetres, hampering current error-correction approaches.

Cosmic ray muon tomography has been recently explored as a non-destructive technique for monitoring or imaging dense well-shielded objects, classically not achievable with traditional tomographic methods. As a recent example of technology transition from high-energy physics to real-world engineering applications, cosmic ray muon tomography has been used with various levels of success in nuclear nonproliferation. However, present muon detection systems have no momentum measurement capabilities and recently developed muon-based radiographic techniques rely only on muon tracking. This unavoidably reduces resolution and requires longer measurement times thus limiting the widespread use of cosmic ray muon tomography. Measurement of cosmic ray muon momenta has the potential to significantly improve the efficiency and resolution of cosmic ray muon tomography. In this paper, we propose and explore the use of momentum-dependent cosmic ray muon tomography using multi-layer gas Cherenkov radiators, a new concept for measuring muon momentum in the field. The muon momentum measurements are coupled with a momentum-dependent imaging algorithm (mPoCA) and image reconstructions are presented to demonstrate the benefits of measuring momentum in cosmic ray muon tomography.

Almost 40 years have now passed since the first instrument was commissioned at the ISIS pulsed muon source. In this time, the facility has grown significantly, with six scheduled instruments producing a wide range of science across a broad range of subject areas. This paper takes a forward look at how we see the facility evolving in the coming years. Upgrades are in progress to develop a state-of-the-art μ SR spectrometer (Super-MuSR) using a novel event-based data acquisition system (Digital Muons). A future project is envisaged to upgrade EMU (nuEMU), exploiting many of the technologies we are currently developing for Super-MuSR. The recent transition of the RIKEN-RAL beamlines to ISIS in 2021 triggered a major upgrade that will be completed with the installation of a new decay solenoid in 2027. Equipped for future running, a new instrument suite is being considered that can best exploit the capabilities of these beamlines. Prototype elemental analysis (MuX) and chip irradiation (MEIS) instruments are now in operation with a growing user community, with plans now well-advanced for a major development in this area. A new instrument for μ ± SR is also planned (CHIMERA), combining the capabilities of existing spectrometers and optimised for experiments exploiting the unique beam properties of RIKEN-RAL. Recent improvements to the present source are considered, together with the exciting opportunities that will come with the development of ISIS-II, the next-generation source/facility, in the 2040s.

Known as one of the most hopeful fields to find new physics beyond the standard model, the anomalous magnetic moment of muon has gained much attention for a long time and become even more important after the Fermi National Accelerator Laboratory’s result came out in 2018. This paper shows the general works and achievements in this exciting field. Those include experiments operated by the Brookhaven National Laboratory and Fermi National Accelerator Laboratory to measure the g-2 factor, the calculation based on the standard model, and a possible extension of the standard model that can explain the experimental results. This paper is an introduction for anyone interested in this field.

We present a measurement of the high-energy astrophysical muon–neutrino flux with the IceCube Neutrino Observatory. The measurement uses a high-purity selection of 650k neutrino-induced muon tracks from the northern celestial hemisphere, corresponding to 9.5 yr of experimental data. With respect to previous publications, the measurement is improved by the increased size of the event sample and the extended model testing beyond simple power-law hypotheses. An updated treatment of systematic uncertainties and atmospheric background fluxes has been implemented based on recent models. The best-fit single power-law parameterization for the astrophysical energy spectrum results in a normalization of ϕ@100TeVνμ+ν¯μ=1.44−0.26+0.25×10−18GeV−1cm−2s−1sr−1 and a spectral index γSPL=2.37−0.09+0.09 , constrained in the energy range from 15 TeV to 5 PeV. The model tests include a single power law with a spectral cutoff at high energies, a log-parabola model, several source-class-specific flux predictions from the literature, and a model-independent spectral unfolding. The data are consistent with a single power-law hypothesis, however, spectra with softening above one PeV are statistically more favorable at a two-sigma level.