NEUT is a neutrino–nucleus interaction simulation program library. It can be used to simulate interactions for neutrinos with between 100 MeV and a few TeV of energy. NEUT is also capable of ...simulating hadron interactions within a nucleus and is used to model nucleon decay and hadron–nucleus interactions for particle propagation in detector simulations. This article describes the range of interactions modelled and how each is implemented.
As accelerator-based neutrino oscillation experiments improve oscillation parameter constraints with more data, control over systematic uncertainties on the incoming neutrino flux and interaction ...models is increasingly important. The intense beams offered by modern experiments permit a variety of options to constrain the flux using in situ “standard candle” measurements. These standard candles must use very well understood interaction processes to avoid introducing additional interaction model dependence. One option often discussed in this context is the “low-
ν
” method, which is designed to isolate neutrino interactions where there is low energy-transfer to the nucleus, such that the interaction cross section is expected to be approximately constant as a function of neutrino energy. The shape of the low-energy transfer event sample can then be used to extract the flux shape. Applications of the method at high neutrino energies (many tens of GeV) are well understood. However, the applicability of the method at the lower energies of current and future few-GeV accelerator neutrino experiments remains unclear due to the presence of nuclear and form-factor effects inherent in the interaction models.In this analysis we examine the prospects for improving constraints on the accelerator neutrino fluxes in situ with the low-
ν
method in an experiment-independent way, using (anti)neutrino interactions on argon and hydrocarbon targets from the GENIE, NEUT, NuWro and GiBUU event generators. We begin by investigating the extent to which deviations from the constant cross-section assumption are dependent on poorly understood aspects of the neutrino interaction model. We then assess whether a low energy-transfer event sample can be confidently identified using experimentally accessible observables. We finally consider how the practicalities of reconstructing the energy spectrum of interacting neutrinos in realistic detectors might further limit the utility of low-
ν
flux constraints. The results show that flux constraints from the low-
ν
method would be severely dependent on the interaction model assumptions used in an analysis of neutrinos with energies below 5 GeV, and anti-neutrinos below at least 15 GeV. The spread of model predictions show that a low-
ν
analysis is unlikely to offer much improvement on typical neutrino flux uncertainties, even with a perfect detector. Notably—running counter to the assumption inherent to the low-
ν
method—the model-dependence increases with decreasing energy transfer for experiments in the few-GeV region.
Event reweighting has been implemented in the NuWro neutrino event generator for a number of free theory parameters in the interaction model. Event reweighting is a key analysis technique, used to ...efficiently study the effect of neutrino interaction model uncertainties. This opens up the possibility for NuWro to be used as a primary event generator by experimental analysis groups. A preliminary model tuning to ANL and BNL data of quasi-elastic and single pion production events was performed to validate the reweighting engine.
In order to make precision measurements of neutrino oscillations using few-GeV neutrino beams a detailed understanding of nuclear effects in neutrino scattering is essential. Recent studies have ...revealed that single-transverse kinematic imbalance (STKI), defined in the plane transverse to an incoming neutrino beam, can act as a unique probe of these nuclear effects. This work first illustrates that an exclusive measurement of STKI at the off-axis near detector of the T2K experiment (ND280) is expected to distinguish the presence of interactions with two nucleons producing two holes (2p-2h) from alterations of the predominant underlying cross-section parameter (MA - the nucleon axial mass). Such a measurement is then demonstrated with fake data, showing substantial nuclear model separation potential.
This thesis presents a selection of neutrino interactions occurring within the Electromagnetic Calorimeters (ECals) of the T2K off-axis near detector, ND280. ND280 is situated 2.5 degrees off axis ...with respect to the J-PARC neutrino beam and is used to constrain the unoscillated neutrino flux for T2K oscillation analyses. The motivation for an ECal-target sample is three-fold: to investigate the neutrino flux across a wider range of off-axis angles than is possible with the main near-detector target; to measure the rate of muon production with a larger angular acceptance than the standard near detector event samples; and to investigate neutrino interactions on lead, a heavy nuclear target on which there is little published data. To enable this analysis, the ECal vertex reconstruction was integrated with the rest of the ND280 reconstruction software. For the first time, the accurate particle identification (PID) and momentum reconstruction capabilities of the ND280 Tracker are used for particles produced in neutrino interactions in the ECals. PID and kinematic reconstruction is not possible using ECal information alone. Using this newly facilitated reconstruction of ECal-originating final-state particles, distributions of the reconstructed kinematics for a sample of charged-current inclusive muon-neutrino interaction candidates are compared between data and simulation. This highlights that a deficiency in the ND280 simulation of entering background particles constitutes a more significant problem than previously believed. The data--simulation agreement seen is reasonable: the shape-only Chi-Square test statistic for the muon-like sample was evaluated to be 245 for 104 analysis bins. This motivates the further use of the ND280 ECals for constraint of the T2K flux prediction as well as heavy-target, neutrino scattering measurements.
Objectives: The arts are increasingly recognised as important and beneficial activities for people living with dementia. However, there is little peer-reviewed published research exploring arts-based ...learning for dementia care staff. In response, this paper explores (a) how dementia care staff describe forms of communication in care settings, and (b) the impact on communication following four sessions of 'Creative Conversations', an arts-based intervention for skills development.
Method: Fourteen care homes received the intervention, delivered as 4 × 2 hour sessions. The intervention uses a range of activities (e.g. poetry, film, music, art making). Twenty-eight care staff were opportunistically sampled (mean age = 42.29), and provided pre-post qualitative data, obtained through interviews. Transcripts were analysed thematically.
Results: At baseline, the dominant 'task-focussed' nature of care work was described as a barrier to communication, challenging opportunities for developing meaningful relationships with residents. Post-intervention, three primary themes were identified regarding improving communication: (1) learning through the arts (secondary themes: simplicity and subtlety, innovation in communication, and strengthening the role of non-verbal communication), (2) Enhancing creative approaches to care (secondary themes: element of surprise, confidence to experiment and catalyst for communication) and (3) professional introspection (secondary themes: development of empathy, sharing knowledge and experiences and a new appreciation).
Conclusions: The intervention validated staff skills and confidence, enabling meaningful interactions that could be creative, 'in the moment', spontaneous and improvised. This arts-based intervention, which departs from formal education and fact-based learning may be particularly useful for the development of the dementia care workforce.
We present a Monte Carlo truth study examining nuclear effects in charged-current neutrino interactions using observables constructed in the transverse plane. Three distributions are introduced that ...show very weak dependence on neutrino flux and its associated uncertainty. Measurements comparing these distributions between quasi-elastic-like and single charged pion final states will provide new constraints of nuclear effects. It is suggested that the on-axis position in the NuMI beam provides the correct flux to take advantage of this reduced energy dependence in measuring nuclear effect-generated transverse imbalances.
NEUT is a neutrino-nucleus interaction simulation. It can be used to simulate interactions for neutrinos with between 100 MeV and a few TeV of energy. NEUT is also capable of simulating hadron ...interactions within a nucleus and is used to model nucleon decay and hadron--nucleus interactions for particle propagation in detector simulations. This article describes the range of interactions modelled and how each is implemented.
Eur. Phys. J. C 82 (2022) 9, 808 As accelerator-neutrino oscillation experiments improve oscillation parameter
constraints, control over systematic uncertainties on the incoming neutrino
flux and ...interaction models is increasingly important. The intense beams
offered by modern experiments permit a variety of options to constrain the flux
using in situ "standard candle" measurements. These standard candles must use
very well understood processes to avoid introducing bias. One option discussed
in this context is the "low-$\nu$" method, designed to isolate neutrino
interactions where there is low energy-transfer to the nucleus, such that the
cross section is expected to be approximately constant as a function of
neutrino energy. The shape of the low-energy transfer event sample can then be
used to extract the flux shape. Applications of the method at high neutrino
energies (many tens of GeV) are well understood. However, the applicability of
the method at the few-GeV energies of current and future accelerator neutrino
experiments remains unclear due to the presence of nuclear and form-factor
effects.
In this analysis we examine the prospects for improving constraints on
accelerator neutrino fluxes with the low-$\nu$ method in an
experiment-independent way, using (anti)neutrino interactions on argon and
hydrocarbon targets from the GENIE, NEUT, NuWro and GiBUU event generators. The
results show that flux constraints from the low-$\nu$ method would be severely
dependent on the specific interaction model assumptions used in an analysis for
neutrino energies less than 5 GeV. The spread of model predictions show that a
low-$\nu$ analysis is unlikely to offer much improvement on typical neutrino
flux uncertainties, even with a perfect detector. Notably -- running counter to
the assumption inherent to the low-$\nu$ method -- the model-dependence
increases with decreasing energy transfer for experiments in the few-GeV
region.
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