The effects of neutron irradiation on materials are often interpreted in terms atomic recoils, initiated by impacts and producing crystal lattice defects. In addition, there is a remarkable two-step process, strongly pronounced the medium-weight heavy elements. This process involves generation energetic {\gamma} photons nonelastic collisions neutrons with nuclei, achieved via capture inelastic reactions. Subsequently, high-energy electrons excited through scattering electrons. We derive...

Abstract Deuterium-tritium fusion reactions produce energy in the form of 14.1 MeV neutrons, and hence reactor components will be exposed to high neutron irradiation while also being subjected thermal, mechanical magnetic loads. Exposure has numerous consequences, including swelling dimensional changes, comparable magnitude peak transient thermal deformations occurring plasma-facing components. Irradiation dynamically alters various thermo-mechanical properties, relating temperature, stress...

Abstract The occurrence of high stress concentrations in reactor components is a still intractable phenomenon encountered fusion design. Here, we observe and quantitatively model non-linear high-dose radiation mediated microstructure evolution effect that facilitates fast relaxation the most challenging low-temperature limit. In situ observations tensioned tungsten wire exposed to high-energy ion beam show internal up 2 GPa relaxes within minutes, with extent time-scale accurately predicted...

Abstract Determining stress and strain in a component of fusion power plant involves defining boundary conditions for the mechanical equilibrium equations, which implies availability full reactor model those conditions. To address this fundamental challenge design, finite element method (FEM) Mega-Ampere Spherical Tokamak Upgrade (MAST-U) tokamak, operating at Culham Campus UKAEA, has been developed applied to assess deformations, strain, tokamak structure, taken as proxy plant. The model,...

The precipitation of hydrides in zirconium alloys is accompanied by a significant and anisotropic volumetric expansion. Previous literature quantified the misfit both theoretically experimentally, but these values differ greatly; experimental are consistently lower. One possibility that measurements include effect dislocations generated hydride, which relax transformation stresses. To test this hypothesis, it important to determine stress field hydride its associated dislocations, combined....

Cosmological gravitational-wave backgrounds are an exciting science target for next-generation ground-based detectors, as they encode invaluable information about the primordial Universe. However, any such background is expected to be obscured by astrophysical foreground from compact-binary coalescences. We propose a novel framework detect cosmological in presence of binary black holes and neutron star signals with including Cosmic Explorer Einstein Telescope. Our procedure involves first...

Abstract Using the notion of eigenstrain produced by defects formed in a material exposed to high energy neutron irradiation, we develop method for computing macroscopic elastic stress and strain arising components fusion power plant during operation. In microstructurally isotropic material, primary cause fields is spatial variation exposure. We show that under traction-free boundary conditions, volume-average always vanishes, signifying formation spatially heterogeneous state, combining...

Next-generation gravitational wave detectors such as the Einstein Telescope and Cosmic Explorer will have increased sensitivity observing volumes, enabling unprecedented precision in parameter estimation. However, this enhanced could also reveal systematic biases arising from waveform modeling, which may impact astrophysical inference. We investigate extent of these over a year-long run with $10^5$ simulated binary black hole sources using linear signal approximation. To establish...

The stochastic gravitational-wave backgrounds (SGWBs) for current detectors are dominated by binary black-hole (BBH) and neutron-star (BNS) coalescences. sensitivity of networks (GW) allows only a small fraction BBHs BNSs to be resolved subtracted, but previous work indicated that the situation should significantly improve with next-generation (XG) observatories. We revisit these conclusions taking into account waveform-modeling uncertainties, updated astrophysical models, (crucially) full...

Neutrons interacting with atomic nuclei in most of the materials included current fusion reactor designs—notably tungsten, ferritic and stainless steels, copper alloys—generate a γ-photon flux that is comparable magnitude energy neutrons, which turn generates an intense high-energy electrons themselves. The occurrence these γ- electron fluxes has implications, among others, for mobility crystal defects materials, stability plasma, internal heating components. While highly spatially resolved...

We carried out discrete dislocation plasticity (DDP) simulations in the infinite-matrix approximation of δ Zr micro-hydrides – including their elastic field - first precipitating and then subjected to an external stress. calculate present density, maximum principal shear stresses, configurational energy density plastic displacement. It was found that even hydrides as thin 20 nm have a large impact on deformation stress build-up, this effect increases for increasing hydride thickness. also...

Stochastic gravitational-wave backgrounds can be of either cosmological or astrophysical origin. The detection an stochastic background with ground-based interferometers is expected in the near future. Perhaps even more excitingly, origin by future could reveal invaluable information about early Universe. From this perspective, a {\it foreground} that prevent extraction from data. In paper, we revisit time-frequency domain notching procedure previously proposed to remove foreground context...

COVID-19 pandemic and the consequent rigid social distancing measures implemented, including school closures, have heavily impacted children's adolescents' psychosocial wellbeing, their mental health problems significantly increased. However, child adolescent were already a serious problem before Pandemic all over world. is not just pandemic, it syndemic mentally or socially disadvantaged children adolescents are most affected. Non-Communicable Diseases (NCDs) previous issues an additional...

Next-generation terrestrial gravitational-wave observatories will detect $\mathcal{O}(10^{5})$ signals from compact binary coalescences every year. These can last for several hours in the detectors' sensitivity band and they be affected by multiple unresolved sources contributing to a confusion-noise background data. Using an information-matrix formalism, we estimate impact of confusion noise power spectral density broadening parameter estimates GW170817-like event. If our is neglected, find...

The occurrence of high stress concentrations in reactor components is a still intractable phenomenon encountered fusion design. We observe and quantitatively model non-linear high-dose radiation mediated microstructure evolution effect that facilitates fast relaxation the most challenging low-temperature limit. In situ observations tensioned tungsten wire exposed to high-energy ion beam show internal up 2 GPa relaxes within minutes, with extent time-scale accurately predicted by...

A finite-element method (FEM) model for the Mega-Ampere Spherical Tokamak - Upgrade (MAST-U) fusion tokamak has been developed to evaluate stress and deformations in full device structure assess stability of whole with respect its simulated exposure an artificial level neutron irradiation. Here, we use MAST-U as a proxy power plant explore fidelity made possible by modern supercomputing systems. Gravity atmospheric pressure were used test high-resolution FEM model, involving excess 122...

Radiation creep and swelling are irreversible deformation phenomena occurring in materials irradiated even at low temperatures. On the microscopic scale, energetic particles initiate collision cascades, generating eliminating defects that then interact coalesce presence of internal external stress. We investigate how copper tungsten swell deform under various applied stress states low- high-energy irradiation limits. Simulations show two metals respond a qualitatively similar manner,...

Determining stress and strain in a component of fusion power plant involves defining boundary conditions for the mechanical equilibrium equations, implying availability full reactor model those conditions. To address this fundamental challenge design, finite element method (FEM) Mega-Ampere Spherical Tokamak Upgrade (MAST-U) tokamak, operating at Culham Campus UKAEA, has been developed applied to assess deformations, strain, tokamak structure, taken as proxy plant. The model, handling 127...