An unexplained >4σ discrepancy persists between "beam" and "bottle" measurements of the neutron lifetime. A new model proposed that conversions of neutrons n into mirror neutrons n^{'}, part of a ...dark mirror sector, can increase the apparent neutron lifetime by 1% via a small mass splitting Δm between n and n^{'} inside the 4.6 T magnetic field of the National Institute of Standards and Technology Beam Lifetime experiment. A search for neutron conversions in a 6.6 T magnetic field was performed at the Spallation Neutron Source which excludes this explanation for the neutron lifetime discrepancy.
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The uptake of microfluidics by the wider scientific community has been limited by the fabrication barrier created by the skills and equipment required for the production of traditional microfluidic ...devices. Here we present simple 3D printed microfluidic devices using an inexpensive and readily accessible printer with commercially available printer materials. We demonstrate that previously reported limitations of transparency and fidelity have been overcome, whilst devices capable of operating at pressures in excess of 2000 kPa illustrate that leakage issues have also been resolved. The utility of the 3D printed microfluidic devices is illustrated by encapsulating dental pulp stem cells within alginate droplets; cell viability assays show the vast majority of cells remain live, and device transparency is sufficient for single cell imaging. The accessibility of these devices is further enhanced through fabrication of integrated ports and by the introduction of a Lego®-like modular system facilitating rapid prototyping whilst offering the potential for novices to build microfluidic systems from a database of microfluidic components.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The usage of Monte Carlo neutrino event generators (MC ν EG s) is a norm within the high-energy ν scattering community. The relevance of quasielastic (QE) energy regimes to ν oscillation experiments ...implies that accurate calculations of ν A cross sections in this regime will be a key contributor to reducing the systematic uncertainties affecting the extraction of oscillation parameters. In spite of this, many MC ν EG s utilize highly phenomenological, parametrized models of QE scattering cross sections. Moreover, a culture of validation of MC ν EG s against prolific electron (e) scattering data has been historically lacking. In this work, we implement new e A cross sections obtained from nuclear ab initio approaches in GENIE, the primary MC ν EG utilized by the FNAL community. In particular, we utilize results from quantum MC methods which solve the many-body nuclear problem in the short-time approximation (STA), allowing consistent retention of two-nucleon dynamics which are crucial to explain available nuclear electromagnetic (electroweak) data over a wide range of energy and momentum transfers. This new implementation in GENIE is fully tested against the world QE electromagnetic data, finding agreement with available data below ∼ 2 GeV of beam energy with the aid of a scaling function formalism. The STA is currently limited to study A ≤ 12 nuclei, however, its semi-inclusive multibody identity components are exportable to other many-body computational techniques such as auxiliary field diffusion MC which can reach A ≤ 40 systems while continuing to realize the factorization contained within the STA's multinucleon dynamics. Together, these developments promise to make future experiments such as DUNE more accurate in their assessment of MC ν EG systematics, ν properties, and potentially empower the discovery of physics beyond the Standard Model.
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The ability to make artificial lipid bilayers compatible with a wide range of environments, and with sufficient structural rigidity for manual handling, would open up a wealth of opportunities for ...their more routine use in real‐world applications. Although droplet interface bilayers (DIBs) have been demonstrated in a host of laboratory applications, from chemical logic to biosynthesis reaction vessels, their wider use is hampered by a lack of mechanical stability and the largely manual methods employed in their production. Multiphase microfluidics has enabled us to construct hierarchical triple emulsions with a semipermeable shell, in order to form robust, bilayer‐bound, droplet networks capable of communication with their external surroundings. These constructs are stable in air, water, and oil environments and overcome a critical obstacle of achieving structural rigidity without compromising environmental interaction. This paves the way for practical application of artificial membranes or droplet networks in diverse areas such as medical applications, drug testing, biophysical studies and their use as synthetic cells.
Encapsulated droplet networks: Droplet networks separated by lipid membranes are encapsulated within a semi‐permeable shell. These cell‐like materials can spatially segregate defined compartments and communicate with the outside world using reconstituted membrane proteins. Such microfluidically prepared membrane constructs are stable in a range of environments.
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6.
Electron scattering and neutrino physics Ankowski, A M; Ashkenazi, A; Bacca, S ...
Journal of physics. G, Nuclear and particle physics,
12/2023, Volume:
50, Issue:
12
Journal Article
Peer reviewed
Open access
Abstract
A thorough understanding of neutrino–nucleus scattering physics is crucial for the successful execution of the entire US neutrino physics program. Neutrino–nucleus interaction constitutes ...one of the biggest systematic uncertainties in neutrino experiments—both at intermediate energies affecting long-baseline deep underground neutrino experiment, as well as at low energies affecting coherent scattering neutrino program—and could well be the difference between achieving or missing discovery level precision. To this end, electron–nucleus scattering experiments provide vital information to test, assess and validate different nuclear models and event generators intended to test, assess and validate different nuclear models and event generators intended to be used in neutrino experiments. Similarly, for the low-energy neutrino program revolving around the coherent elastic neutrino–nucleus scattering (CEvNS) physics at stopped pion sources, such as at ORNL, the main source of uncertainty in the evaluation of the CEvNS cross section is driven by the underlying nuclear structure, embedded in the weak form factor, of the target nucleus. To this end, parity-violating electron scattering (PVES) experiments, utilizing polarized electron beams, provide vital model-independent information in determining weak form factors. This information is vital in achieving a percent level precision needed to disentangle new physics signals from the standard model expected CEvNS rate. In this white paper, we highlight connections between electron- and neutrino–nucleus scattering physics at energies ranging from 10 s of MeV to a few GeV, review the status of ongoing and planned electron scattering experiments, identify gaps, and lay out a path forward that benefits the neutrino community. We also highlight the systemic challenges with respect to the divide between the nuclear and high-energy physics communities and funding that presents additional hurdles in mobilizing these connections to the benefit of neutrino programs.
Searches for baryon number violation, including searches for proton decay and neutron-antineutron transformation (n→n¯), are expected to play an important role in the evolution of our understanding ...of beyond standard model physics. The n→n¯ is a key prediction of certain popular theories of baryogenesis, and experiments such as the Deep Underground Neutrino Experiment and the European Spallation Source plan to search for this process with bound- and free-neutron systems. Accurate simulation of this process in Monte Carlo will be important for the proper reconstruction and separation of these rare events from background. This article presents developments towards accurate simulation of the annihilation process for use in a cold, free neutron beam for n→n¯ searches from n¯C annihilation, as C612 is the target of choice for the European Spallation Source’s NNBar Collaboration. Initial efforts are also made in this paper to perform analogous studies for intranuclear transformation searches in Ar1840 nuclei.
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The added value of using photographs to explore experiences has been embraced in research methods such as photo-elicitation and Photovoice. Despite evidence that photographs aid communication and ...understanding, there is little research investigating photograph use within cognitive behavioural therapy. This project explores participant experiences of taking and sharing photographs within a dialectical behaviour therapy (DBT)-informed emotional coping skills group intervention. Five service users were recruited from groups that had implemented the taking and sharing of photographs as a feature of homework tasks and feedback. Semi-structured interviews were conducted, using the photographs taken for the group as prompts, and interpretive phenomenological analysis was used to develop themes. Group evaluation data were used to support the analysis. Participants were positive about the impact of the photographs, despite initially experiencing anxieties regarding sharing them. The task supported them to express themselves in ways that added value to verbal feedback, which had benefits for group relationships and for the therapeutic tasks such as mindful observing. Further research is indicated, given the small sample and participants all being white, working-age females. However, the findings suggest that using photographs as homework tasks could support communication and the exploration of experiences that may be difficult to express using words.
Abstract
Baryon number conservation is not guaranteed by any fundamental symmetry within the standard model, and therefore has been a subject of experimental and theoretical scrutiny for decades. So ...far, no evidence for baryon number violation has been observed. Large underground detectors have long been used for both neutrino detection and searches for baryon number violating processes. The next generation of large neutrino detectors will seek to improve upon the limits set by past and current experiments and will cover a range of lifetimes predicted by several Grand Unified Theories. In this White Paper, we summarize theoretical motivations and experimental aspects of searches for baryon number violation in neutrino experiments.