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1.	Abdul-Hafidh, Esam H., et al. (författare) Incompressibility of face-centered cubic structure in Metallic Nanosolids 2021 Ingår i: Physica Scripta. - : Institute of Physics Publishing (IOPP). - 0031-8949 .- 1402-4896. ; 96:12 Tidskriftsartikel (refereegranskat)abstract A simple and general theoretical model has been constructed to study the bulk modulus 'B' of FCC nanoparticles and nanostructures. In order to justify the experimental results of the anomalous behavior of B in nanosolids, this method considers the competing effect of both size and shape of a nanoparticle on B. In this work, the relationship between B and the surface energy has been derived based on the dangling bond energy model. The results show that B depends on size, shape and structure of FCC nanocrystalline solids (nanosolids). Our results show that as the shape changes from spherical to deformed, nanosolids become incompressible and B increases as the size decreases. The obtained theoretical results were compared with the experimental predictions for silver, gold and nickel. A very good agreement between theoretical results and experiments was found for silver and nickel. While in gold, we noticed a deviation from the experiment, which is attributed to extreme deformation of the nanogold.
2.	Alexander, Gerianne, et al. (författare) The sounds of science-a symphony for many instruments and voices 2020 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 95:6 Tidskriftsartikel (refereegranskat)abstract Sounds of Science is the first movement of a symphony for many (scientific) instruments and voices, united in celebration of the frontiers of science and intended for a general audience. John Goodenough, the maestro who transformed energy usage and technology through the invention of the lithium-ion battery, opens the programme, reflecting on the ultimate limits of battery technology. This applied theme continues through the subsequent pieces on energy-related topics-the sodium-ion battery and artificial fuels, by Martin Mansson-and the ultimate challenge for 3D printing, the eventual production of life, by Anthony Atala. A passage by Gerianne Alexander follows, contemplating a related issue: How might an artificially produced human being behave? Next comes a consideration of consciousness and free will by Roland Allen and Suzy Lidstrom. Further voices and new instruments enter as Warwick Bowen, Nicolas Mauranyapin and Lars Madsen discuss whether dynamical processes of single molecules might be observed in their native state. The exploitation of chaos in science and technology, applications of Bose-Einstein condensates and the significance of entropy follow in pieces by Linda Reichl, Ernst Rasel and Roland Allen, respectively. Mikhail Katsnelson and Eugene Koonin then discuss the potential generalisation of thermodynamic concepts in the context of biological evolution. Entering with the music of the cosmos, Philip Yasskin discusses whether we might be able to observe torsion in the geometry of the Universe. The crescendo comes with the crisis of singularities, their nature and whether they can be resolved through quantum effects, in the composition of Alan Coley. The climax is Mario Krenn, Art Melvin and Anton Zeilinger's consideration of how computer code can be autonomously surprising and creative. In a harmonious counterpoint, his 'Guidelines for considering AIs as coauthors', Roman Yampolskiy concludes that code is not yet able to take responsibility for coauthoring a paper. An interlude summarises a speech by Zdenek Papousek. In a subsequent movement, new themes emerge as we seek to comprehend how far we have travelled along the path to understanding, and speculate on where new physics might arise. Who would have imagined, 100 years ago, a global society permeated by smartphones and scientific instruments so sophisticated that genes can be modified and gravitational waves detected?
3.	Banerjee, S., et al. (författare) Time delay in negative ion photodetachment 2021 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 96:11 Tidskriftsartikel (refereegranskat)abstract Time delay in photodetachment has been investigated for few negative ions, Cl-, Br-, I-, and Li-. Very few studies on photodetachment time delay for negative ions are present till date and have been reviewed briefly in the present article. Different many body formalisms, like RRPA, RRPA-R and RMCTD, have been employed to obtain new results on photodetachment time delay, accounting for important electron correlations present in the negative ions studied here. Results on time delay show significant angle dependence near the threshold region, at shape resonance and at Cooper minimum region.
4.	Bouziani, I, et al. (författare) Electronic and optical properties of ZnO nanosheet doped and codoped with Be and/or Mg for ultraviolet optoelectronic technologies : density functional calculations 2020 Ingår i: Physica Scripta. - : IOP PUBLISHING LTD. - 0031-8949 .- 1402-4896. ; 95:1 Tidskriftsartikel (refereegranskat)abstract Theoretically, the density functional calculations have been effectuated for investigating electronic and optical properties of zinc oxide nanosheet doped and codoped with Be and/or Mg utilizing the generalized gradient approximation modified Becke-Johnson (GGA-mBJ) approach. The computed results show that the ZnBeO, ZnMgO and ZnBeMgO in nanosheet structure, referring to their low formation energy values, are more stable than those in bulk one. Furthermore, the bandgap of ZnO monolayer can be effectively modulated through substitution of Zn atoms by Be and/or Mg. In addition to that, by incorporating Be and/or Mg, the absorption peaks of ZnO nanosheet shift into the shorter UV-wavelength side as well as its reflectivity becomes lower. These results indicate that doping and codoping process of ZnO monolayer with Be and/or Mg are two efficient ways to modulate electronic and optical properties for ultraviolet optoelectronic technologies.
5.	Buermans, J., et al. (författare) Study of the Electron cyclotron power deposition in TOMAS 2024 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 99:8 Tidskriftsartikel (refereegranskat)abstract Efficient Electron Cyclotron Resonance Heating (ECRH) breakdown and pre-ionization can be achieved with fundamental X-mode, while higher harmonics can introduce excessive stray radiation. Fundamental heating however is characterized by a low cut-off density, introducing additional power absorption mechanisms in the plasma. A good knowledge of these mechanisms is necessary to use fundamental X-mode as an efficient pre-ionization method. Numerous experiments were performed on the TOroidally MAgnetized System (TOMAS) to study the power deposition for ECRH in helium. It is a facility designed to study plasma production, wall conditioning and plasma-surface interactions and is operated by LPP-ERM/KMS at the FZ-J & uuml;lich. The influence of the injected power P EC and the magnetic field B 0 on the absorption mechanisms is examined, in order to reduce stray radiation and improve the absorption efficiency. This will allow to determine the best scenarios for plasma start-up and pre-ionization.
6.	Cabrera-Trujillo, Remigio, 1969 (författare) Electronic energy levels and wave-functions evolution from 3-D to 2-D of a hydrogen atom confined by two parallel planes 2024 Ingår i: PHYSICA SCRIPTA. - 0031-8949 .- 1402-4896. ; 99:6 Tidskriftsartikel (refereegranskat)abstract The compression of an atom produced by two planes induces a change in its electronic structure that evolves from a free atom in 3-D to a 2-D atom. This behavior is of importance in low-dimensional materials and high compression produced by an anvil cell. In this work, we study the evolution of the energy levels and electronic wave-functions of a hydrogen atom placed between two impenetrable planes as a function of the inter-plane separation through a numerical approach. As the inter-plane separation is reduced, the electron motion is restricted along the direction normal to the planes, similar to a particle in a box, while leaving the electron to move unrestricted along the planes, thus, breaking the spherical geometry of the H atom caused by the planes' compression. The energy levels evolve from 3-D, described by nlm quantum numbers to a 2-D described by n ' ml ' , where l ' is the quantum number for a particle in a box along the z direction and n ' is the principal quantum number of the 2-D atom radial direction. We evaluate the energy levels from 3-D to 2-D and the radial average distance in cylindrical coordinates, as a function of the inter-plane separation D along the z-direction. We find that as the inter-plane separation is reduced, the angular momentum quantum number l merges to the z-component of the angular momentum and it produces two branches, a symmetric for l-even and one anti-symmetric for l-odd, connected to a particle in a box quantum number l ' along the z-axis with implications in the atom photo-luminescence, resulting from the symmetry of the system. Furthermore, states with l-odd merge with states with l-even, as they have the same energy and average distance when D -> 0. We provide an Aufbau principle for it. Our results agree to the analytical solutions at the 3-D and 2-D limiting cases.
7.	Cabrera-Trujillo, Remigio, 1969 (författare) Molecular electronic stopping cross section for H and He beams colliding with water: projectile charge state contribution 2023 Ingår i: Physica Scripta. - 0031-8949. ; 98:12 Tidskriftsartikel (refereegranskat)abstract When an ion beam impinges on a target material, electron stripping and capture processes involve different charge fraction states in the beam, such that each projectile charge state produces a different energy-loss. In this work, the energy deposition of swift hydrogen and helium ion beams colliding with a water target in the gas phase is studied. The electronic structure of the molecular target is represented in terms of core, bond, and lone pair orbital decomposition within a Harmonic Oscillator representation. In this way, the stopping cross section becomes only a function of the orbital mean excitation energy, I 0i . The ion beam charge fraction compositions colliding on water is determined from the work of Wedlund et al (2019) Astronomy & Astrophysics, 630, A36) by accounting for the electron transfer cross sections. We find that the larger the projectile charge state, the larger the electronic stopping cross section and that the beam charge fraction determines the position of the maximum of the electronic stopping curve. Also, in agreement with the experiment, evidence is given on the dominant role of the largest projectile charge state in defining the stopping cross section for high energy collisions, while for low collision energies it is the lowest charge state together with all possible charge states contributing at the maximum of the electronic stopping cross section curve. Our results are reported and compared to available experimental data showing an excellent agreement to the available literature.
8.	Catarino, N., et al. (författare) Deposition in the tungsten divertor during the 2011-2016 campaigns in JET with ITER-like wall 2020 Ingår i: Physica Scripta. - : IOP PUBLISHING LTD. - 0031-8949 .- 1402-4896. ; T171:1 Tidskriftsartikel (refereegranskat)abstract A build-up of co-deposits in remote areas of the divertor can contribute significantly to the overall fuel retention. The control of plasma-material interactions via the study and understanding of erosion-deposition of PFCs provides vital information for the efficient future operation of ITER. The major aim of this work is to reveal details of beryllium deposition and fuel (deuterium) retention on divertor plasma-facing components removed from the JET ITER-Like Wall divertor after cumulative exposure during the first two (ILW-1+2) and all three (ILW-1+2+3) campaigns. Ion beam analysis techniques such as Rutherford backscattering spectrometry, nuclear reaction analysis and proton induced x-ray emission have been extensively used for post-mortem analyses of selected tiles from JET following each campaign and can provide relevant information on plasma-surface interactions like tungsten erosion, beryllium deposition and plasma fuel retention with divertor tiles via implantation or co-deposition. The studied divertor tiles represent a unique set of samples, which have been exposed to plasmas since the beginning of the JET-ILW operation for three successive plasma campaigns. This is a comprehensive comparison of divertor components after these operation periods. The results presented summarise deposition and fuel retention on Tiles 4 (inner base) and 6 (outer base). Although the deposition pattern is similar to that determined after individual campaigns, D retention is not a cumulative process and is determined mainly by the last campaign, and the total Be deposit after the 3 campaigns (i.e. data 1+2+3=tile exposed 2011-2016) is less than the sum of the deposits after each individual campaign (sum 1+2+3) for Tile 4 but greater for Tile 6.
9.	Coburn, J., et al. (författare) First wall energy deposition during vertical displacement events on ITER 2020 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; T171:1 Tidskriftsartikel (refereegranskat)abstract The beryllium (Be) first wall energy deposition and melt damage profiles resulting from the current quench phase of an unmitigated, 5 MA/1.8 T upward vertical displacement event for ITER are investigated. Time dependent 2D magnetic flux profiles are calculated with the DINA code and used as input for the SMITER 3D field line tracing software. 3D maps of the wetted area and perpendicular heat flux q(perpendicular to) show that the majority of the energy deposition occurs on the upper first wall panels #8 and #9 SMITER simulations predict q(perpendicular to,peak) approximate to 190 MW m(-2) on the surfaces of upper FWPs #8 and #9 at the end of the similar to 450 ms current quench. The surface heat flux maps generated by SMITER are used as input in the MEMOS-U code, which models Be melt formation and dynamics. Simulations reveal peak surface temperatures of similar to 2200 K, inward surface damage of similar to 0.5 mm in depth, and average melt velocities of similar to 2 m s(-1). Although VDEs are in principle the easiest disruptive instability to avoid, the analysis demonstrates that any non-mitigated events or intentional VDEs taking place during low I-p, early operational phases of ITER for the purposes of estimating disruption forces, must be kept to a low number.
10.	Corre, Y., et al. (författare) Sustained W-melting experiments on actively cooled ITER-like plasma facing unit in WEST 2021 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 96:12 Tidskriftsartikel (refereegranskat)abstract The consequences of tungsten (W) melting on divertor lifetime and plasma operation are high priority issues for ITER. Sustained and controlled W-melting experiment has been achieved for the first time in WEST on a poloidal sharp leading edge of an actively cooled ITER-like plasma facing unit (PFU). A series of dedicated high power steady state plasma discharges were performed to reach the melting point of tungsten. The leading edge was exposed to a parallel heat flux of about 100 MW.m(-2) for up to 5 s providing a melt phase of about 2 s without noticeable impact of melting on plasma operation (radiated power and tungsten impurity content remained stable at constant input power) and no melt ejection were observed. The surface temperature of the MB was monitored by a high spatial resolution (0.1 mm/pixel) infrared camera viewing the melt zone from the top of the machine. The melting discharge was repeated three times resulting in about 6 s accumulated melting duration leading to material displacement from three similar pools. Cumulated on the overall sustained melting periods, this leads to excavation depth of about 230 mu m followed by a re-solidified tungsten bump of 200 mu m in the JxB direction.
11.	Dieckmann, Mark Eric, et al. (författare) PIC simulations of stable surface waves on a subcritical fast magnetosonic shock front 2023 Ingår i: Physica Scripta. - : IOP Publishing Ltd. - 0031-8949 .- 1402-4896. ; 98:9 Tidskriftsartikel (refereegranskat)abstract We study with particle-in-cell (PIC) simulations the stability of fast magnetosonic shocks. They expand across a collisionless plasma and an orthogonal magnetic field that is aligned with one of the directions resolved by the 2D simulations. The shock speed is 1.6 times the fast magnetosonic speed when it enters a layer with a reduced density of mobile ions, which decreases the shock speed by up to 15% in 1D simulations. In the 2D simulations, the density of mobile ions in the layer varies sinusoidally perpendicularly to the shock normal. We resolve one sine period. This variation only leads to small changes in the shock speed evidencing a restoring force that opposes a shock deformation. As the shock propagates through the layer, the ion density becomes increasingly spatially modulated along the shock front and the magnetic field bulges out where the mobile ion density is lowest. The perturbed shock eventually reaches a steady state. Once it leaves the layer, the perturbations of the ion density and magnetic field oscillate along its front at a frequency close to the lower-hybrid frequency; the shock is mediated by a standing wave composed of obliquely propagating lower-hybrid waves. We perform three 2D simulations with different box lengths along the shock front. The shock front oscillations are aperiodically damped in the smallest box with the fastest variation of the ion density, strongly damped in the intermediate one, and weakly damped in the largest box. The shock front oscillations perturb the magnetic field in a spatial interval that extends by several electron skin depths upstream and downstream of the shock front and could give rise to Whistler waves that propagate along the shock's magnetic field overshoot. Similar waves were observed in hybrid and PIC simulations and by the MMS satellite mission.
12.	Dieckmann, Mark E, 1969-, et al. (författare) Weibel- and non-resonant Whistler wave growth in an expanding plasma in a 1D simulation geometry 2024 Ingår i: Physica Scripta. - : IOP Publishing Ltd. - 0031-8949 .- 1402-4896. ; 99:4 Tidskriftsartikel (refereegranskat)abstract Ablating a target with an ultraintense laser pulse can create a cloud of collisionless plasma. A density ramp forms, in which the plasma density decreases and the ion's mean speed increases with distance from the plasma source. Its width increases with time. Electrons lose energy in the ion's expansion direction, which gives them a temperature anisotropy. We study with one-dimensional particle-in-cell simulations the expansion of a dense plasma into a dilute one, yielding a density ramp similar to that in laser-plasma experiments and a thermal-anisotropy-driven instability. Non-propagating Weibel-type wave modes grow in the simulation with no initial magnetic field. Their magnetic field diffuses across the shock and expands upstream. Circularly polarized propagating Whistler waves grow in a second simulation, in which a magnetic field is aligned with the ion expansion direction. Both wave modes are driven by non-resonant instabilities, they have similar exponential growth rates, and they can leave the density ramp and expand into the dilute plasma. Their large magnetic amplitude should make them detectable in experimental settings.
13.	Dittrich, Laura, et al. (författare) Fuel retention and erosion-deposition on inner wall cladding tiles in JET-ILW 2021 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 96:12 Tidskriftsartikel (refereegranskat)abstract The morphology of beryllium coatings on the Inconel inner wall cladding tiles after JET-ILW campaigns was determined. The focus was on: (i) fuel retention and its share in the overall fuel inventory; (ii) the change of the layer structure and composition. The study is motivated in the view of planned D-T operation in JET. Four tiles were examined: the initial not exposed; one exposed to two campaigns (ILW1-2) and two facing the plasma during ILW1-3. As determined with ion beam and microscopy methods, the initial Be layer (9.0 mu m thick) contained up to 4-5 at.% of impurities, mainly H, O, C, Ni. In the exposed tiles, the impurity content increases to 14-26 at.% (up to 20 at.% O, 1.7 at.% C, 1.0 at.% N, 1.3 at.% Ni and under 0.1 at.% W). The surface composition indicates gettering of O and a long-term retention of N. The Be thickness on the tile exposed to ILW1-2 was between 7.6 and 9.7 mu m, thus indicating erosion in some areas, while the thickness after ILW1-3 increased to 10-12 mu m. The D content was in the range 1.2-3.4x10(17) cm(-2) after ILW1-2 and 3.2-10x10(17) cm(-2) after ILW1-3 on most of the analyzed area, but in the limiter shadow values up to 58 x10(17) cm(-2) were measured. Taking into account the total area of the Be-coated inner wall cladding tiles, the lower limit of D inventory amounts to 5.3x10(22) atoms corresponding to about 176 mg, i.e. somewhat greater than the amount determined on Be limiters. The formation and spalling-off of Be-O particles was revealed.
14.	Forslund, Ola Kenji, et al. (författare) Co-existence of short- and long-range magnetic order in LaCo2P2 2021 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 96:12, s. 125864- Tidskriftsartikel (refereegranskat)abstract The ferromagnetic (FM) nature of the metallic LaCo2P2 was investigated with the positive muon spin rotation, relaxation and resonance (μ+SR) technique. Transverse and zero field μ+ SR measurements revealed that the compound enters a long range FM ground state at K, consistent with previous studies. Based on the reported FM structure, the internal magnetic field was computed at the muon sites, which were predicted with first principles calculations. The computed result agree well with the experimental data. Moreover, although LaCo2P2 is a paramagnet at higher temperatures T > 160 K, it enters a short range ordered (SRO) magnetic phase for K. Measurements below the vicinity of revealed that the SRO phase co-exists with the long range FM order at temperatures 124 K . Such co-existence is an intrinsic property and may be explained by an interplay between spin and lattice degree of freedoms.
15.	Fortuna-Zalesna, E., et al. (författare) Decommissioning of TEXTOR : properties of the Inconel liner 2020 Ingår i: Physica Scripta. - : IOP PUBLISHING LTD. - 0031-8949 .- 1402-4896. ; T171:1 Tidskriftsartikel (refereegranskat)abstract The final shut-down of Tokamak Experiment for Technology Oriented Research in year 2013 created unique opportunities for multi-directional studies of in-vessel components. A set of specimens from the Inconel liner parts was collected in order to assess material properties after 26 years of exploitation. The metal surfaces were covered with up to several mu m thick co-deposits rich in boron, carbon and silicon. Detailed examination of the co-deposits and nearsurface structure of Inconel performed with Transmission Electron Microscopy (TEM) revealed: (i) stratified character of the deposits; (ii) a similar to 200 nm thick layer identified as NiSi2 phase at the interface between the deposit and Inconel substrate; (iii) changed Inconel surface layer. TEM studies of the Inconel structure revealed its polycrystalline character with a mean grain size, low dislocation density and a significant number of heterogeneously distributed primary carbides.
16.	Fortuna-Zalesna, E., et al. (författare) Dust generation and accumulation in JET-ILW : morphology and stability of co-deposits on main plasma-facing components and wall probes 2021 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 96:12 Tidskriftsartikel (refereegranskat)abstract Dust particles and co-deposits were sampled for the first time from beryllium limiters and bulk tungsten divertor (both after ILW-3), and test mirrors from the main chamber after ILW-2 and ILW-3. The focus was on the morphology of molten particles and metal outgrowths. In parallel, the stability of beryllium layers under the impact of hot water was examined on limiters and Be coatings. The study performed by several microscopy methods including SEM, AFM, FIB, TEM and Be-sensitive EDX has revealed: (i) an asymmetric distribution of Be particles with the largest objects (125-550 mu m) on side surfaces of the Be tile: (ii) the presence of highly porous particles, resembling blisters; (iii) very few thin flakes of co-deposits on the divertor, on the shadowed edge of lamella; (iv) the elemental composition and internal structure of the needle-shaped outgrowths on the mirrors: MoO; (v) no detectable impact of water on the beryllium morphology.
17.	Garcia-Valladares, G., et al. (författare) Stochastic resetting with refractory periods : pathway formulation and exact results 2024 Ingår i: Physica Scripta. - 0031-8949 .- 1402-4896. ; 99:4 Tidskriftsartikel (refereegranskat)abstract We look into the problem of stochastic resetting with refractory periods. The model dynamics comprises diffusive and motionless phases. The diffusive phase ends at random time instants, at which the system is reset to a given position-where the system remains at rest for a random time interval, termed the refractory period. A pathway formulation is introduced to derive exact analytical results for the relevant observables in a broad framework, with the resetting time and the refractory period following arbitrary distributions. For the paradigmatic case of Poissonian distributions of the resetting and refractory times, in general with different characteristic rates, closed-form expressions are obtained that successfully describe the relaxation to the steady state. Finally, we focus on the single-target search problem, in which the survival probability and the mean first passage time to the target can be exactly computed. Therein, we also discuss optimal strategies, which show a non-trivial dependence on the refractory period.
18.	Hörnedal, Niklas, et al. (författare) Tight lower bounds on the time it takes to generate a geometric phase 2023 Ingår i: Physica Scripta. - : Institute of Physics (IOP). - 0031-8949 .- 1402-4896. ; 98:10 Tidskriftsartikel (refereegranskat)abstract Geometric phase is a concept of central importance in virtually every branch of physics. In this paper, we show that the evolution time of a cyclically evolving quantum system is restricted by the system's energy resources and the geometric phase acquired by the state. Specifically, we derive and examine three tight lower bounds on the time required to generate any prescribed Aharonov-Anandan geometric phase. The derivations are based on recent results on the geometric character of the Mandelstam-Tamm and Margolus-Levitin quantum speed limits.
19.	Jääskeläinen, Markku (författare) Spatial and temporal bounds on quantum effects for micro-organisms 2020 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 95:7 Tidskriftsartikel (refereegranskat)abstract Progress in the experimental nano-sciences and laser cooling has led to the manipulation of material objects with sizes and temperatures such that quantum effects start to appear. This range of sizes coincides with that of the smallest bacteria as well as of the largest viruses, and is often considered to be the boundary between living and nonliving entities. Experiments are rapidly progressing towards putting micro-organisms into quantum superposition states in a controlled manner, resulting in nontrivial quantum effects that we normally do not attribute to living systems. In order to set limits for the occurrence of such effects, I model micro-organisms quantum mechanically and investigate how relevant physical properties are modified from their classical bulk values in the presence of classical self-gravity. The results show that a transition between quantum-like and classical behavior exists right at sizes corresponding to the broad boundary between the smallest bacteria and the largest giant viruses.
20.	Kantre, Karim-Alexandros, et al. (författare) Combination of in-situ ion beam analysis and thermal desorption spectroscopy for studying deuterium implanted in tungsten 2021 Ingår i: Physica Scripta. - : Institute of Physics Publishing (IOPP). - 0031-8949 .- 1402-4896. ; 96:12 Tidskriftsartikel (refereegranskat)abstract We demonstrate a combinatorial approach integrating ion implantation followed by thermal annealing and simultaneous in situ ion beam analysis with thermal desorption spectroscopy in a single set-up. Atomic and molecular deuterium ions of 3 keV were implanted into bulk tungsten with doses exceeding 1 x 10(22) ions m(-2). Depth profiling of both, protium and deuterium was performed by elastic recoil detection analysis, while simultaneously the outgassing rates of molecular deuterium by thermal desorption spectroscopy were monitored during temperature ramps from room temperature to approximate to 1400 K. The combination of the two techniques in situ is shown capable to identify the distinct retention behavior of deuterium at different temperatures and in different reservoirs, e.g. located close to the surface and diffused deep into the material. Ex-situ scanning electron microscopy confirmed blister formation, and recovery of the initial surface morphology after high temperature annealing, in analogy to comprehensive ex-situ studies.
21.	Karimov, A. R., et al. (författare) Dynamics of charged aerosols relevant to transmission of airborne infections 2022 Ingår i: Physica Scripta. - : IOP Publishing Ltd. - 0031-8949 .- 1402-4896. ; 97:8 Tidskriftsartikel (refereegranskat)abstract A simple model including the effects of initial velocity, air drag, gravity, and electrostatics on the dynamics of airborne droplets emitted from humans is presented. It is found that relatively large droplets can also travel far if their charge and/or the atmospheric electric field is sufficiently large.
22.	Karlsson, Erik B. (författare) Entanglement created in scattering processes 2021 Ingår i: Physica Scripta. - : Institute of Physics Publishing (IOPP). - 0031-8949 .- 1402-4896. ; 96:2 Tidskriftsartikel (refereegranskat)abstract Quantum entanglement is a basic ingredient in the formalism of quantum mechanics and was held by Heisenberg as its most emblematic feature. But although all its consequences could be foreseen from the start, it took half a century before experiments were carried out to test its more intriguing predictions. One reason was that sufficiently sensitive tools, like lasers, were not yet available, but there was also a lack of interest and imagination among theoreticians, who did not realize its full potential. When experiments were finally realized and opened a 'weird and ghostlike quantum world', they were first met with surprise and doubt. In the first experiments on entanglement it was purposely created (using chain-decays or down-conversion), but entanglement is actually a ubiquitous phenomenon appearing in most physical processes, although surviving over so short time-scales that it is usually not observed. The present work deals with 'measurement-induced entanglement' in scattering, and starts with a process where its effects can actually be studied in the sub-femtosecond range in a time-resolved manner, the Compton scattering of neutrons. Based on results from this method, the conditions for observing similar effects in other scattering processes are discussed. First, the mechanisms for entanglement creation by a scattering particle are mentioned, then the conditions for observing measurable consequences of it on scattering cross-sections: a very limited number of scattering centers, large zero-point motions of the scatterers and no strong interaction with environment which leads to decoherence.
23.	Karlsson, Erik B. (författare) Quantum entanglement in low-energy neutron-proton scattering and its possible consequences 2020 Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 95 Tidskriftsartikel (refereegranskat)abstract Quantum entanglement in scattering processes has most often been treated in general terms only. A few examples of detailed calculations exist for atomic systems but for nuclear processes it is an almost unexplored area, although it may be important for interpretation of some measured quantities. The present treatment is a study of the time-development of the deuteron-like compound state created in the n–p scattering process. The increase and decay of neutron–proton entanglement in this state is calculated for low transferred momenta over the atto-second range. It is well known that the very high value for the bound proton cross sections (σ = 81.9 barns) is caused by a specific feature in the deuteron, a virtual 0+ state close to its binding level. In scattering this state causes a negative phase shift δs in the outgoing neutron wave function, increasing linearly with the transferred momentum. This phase shift is produced during a short-lived virtual energy transfer ΔE in exciting the 0+ state and ΔE is estimated here from the ratio of the phase shift δ observed and the time Δt it takes to create the entanglement. It is further argued that the nuclear excitation decreases after the n–p encounter in proportion to the degree of n–p entanglement calculated, i.e. as long as the scattering state has deuteron characteristics. This phase shift is neglected in low energy neutron scattering text-books (which are based on the Fermi pseudo potential) and may be negligible for thermal neutron scattering, but will be important already at epithermal energies (0.1–1 eV). The phase shift has measurable consequences in interpretation of INS (inelastic neutron scattering) since its associated energy shift increases quadratically with the transferred momentum. It explains quantitatively certain anomalies found in scattering on water, where water vibration modes are excited far below the expected transferred momentum limit. This paper ends with a short discussion about quantum entanglement in scattering processes in general, with the present example as a starting point.
24.	Khan, Abdul Rauf, et al. (författare) Investigation of reduced reverse degree based polynomials & indices of gold crystals 2024 Ingår i: Physica Scripta. - : Institute of Physics (IOP). - 0031-8949 .- 1402-4896. ; 99:7 Tidskriftsartikel (refereegranskat)abstract Gold is widely recognized as a noble metal due to its inherent inertness in its bulk form. Nevertheless, gold exhibits reactivity in its ionic form. The inert qualities of bulk gold have led to its extensive recognition as a fundamental raw ingredient in several biomedical processes. These applications encompass drug delivery microchips, dental prostheses, reconstructive surgery, food additives, and endovascular stents. Gold in large amounts can be thought of as safe. Gold can also exist as molecules or ions, specifically gold ions, making it easier to make gold nanomaterials. The distinctive characteristics of gold set it apart from its molecular or bulk states, making its execution a very efficient instrument in the field of nanomedicine. Some of these traits are ease of synthesis, a higher ratio of surface area to volume, more reactive particles, the ability to withstand changes to the surface, and strong optical properties. The reduced reverse degree-based polynomials and topological descriptors of the molecular structure of the gold crystal are investigated in this manuscript. The numerical and graphical analysis of outcomes this study are also described.
25.	Krat, S., et al. (författare) Comparison of erosion and deposition in JET divertor during the first three ITER-like wall campaigns 2020 Ingår i: Physica Scripta. - : IOP PUBLISHING LTD. - 0031-8949 .- 1402-4896. ; T171:1 Tidskriftsartikel (refereegranskat)abstract The manuscript presents an overview of the erosion and deposition data in the inner and outer JET divertor observed during the first three ITER-like wall campaigns (JET-ILW1, JET-ILW2, JET-ILW3). Erosion and deposition were studied using core samples cut out from divertor tiles. For the studied samples a similar general deposition pattern was observed in all three campaigns: More than 60% of the total deposition occurred in the upper region of the inner divertor on tiles 0 and 1, where Be was transported and deposited from the scrape-off layer. High erosion was observed only on tile 5. In JET-ILW2 and 3, erosion together with high power fluxes was observed in the outer divertor at the bottom of tile 7. Additionally, deposition peaks were observed on the sloping parts of tiles 4 and 6, which were more pronounced in JET-ILW2 and 3 due to placing the strike point more often on these tiles. The deposits consisted primarily of Be, with some additional D and C. Deposition rates were observed to decrease from campaign to campaign, with the C deposition rate decreasing the most, more than 2 times from JET-ILW1 to JET-ILW3. D retention up to levels of similar to 1 at% was observed up to large depths in the W protective coatings in all campaigns.

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