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1.	Carbone, Lisa, et al. (författare) Generators and relations for (generalised) Cartan type superalgebras 2019 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1194:1 Konferensbidrag (refereegranskat)abstract In Kac's classification of finite-dimensional Lie superalgebras, the contragredient ones can be constructed from Dynkin diagrams similar to those of the simple finite-dimensional Lie algebras, but with additional types of nodes. For example, A(n-1,0) = s (1\|n) can be constructed by adding a "gray" node to the Dynkin diagram of An-1 = s (n), corresponding to an odd null root. The Cartan superalgebras constitute a difierent class, where the simplest example is Wpnq, the derivation algebra of the Grassmann algebra on n generators. Here we present a novel construction of Wpnq, from the same Dynkin diagram as A(n-1,0), but with additional generators and relations.
2.	Goienetxea Uriarte, Ainhoa, 1983-, et al. (författare) System design and improvement of an emergency department using Simulation-Based Multi-Objective Optimization 2015 Ingår i: Journal of Physics, Conference Series. - : Institute of Physics Publishing (IOPP). - 1742-6588 .- 1742-6596. ; 616:1 Tidskriftsartikel (refereegranskat)abstract Discrete Event Simulation (DES) is nowadays widely used to support decision makers in system analysis and improvement. However, the use of simulation for improving stochastic logistic processes is not common among healthcare providers. The process of improving healthcare systems involves the necessity to deal with trade-off optimal solutions that take into consideration a multiple number of variables and objectives. Complementing DES with Multi-Objective Optimization (SMO) creates a superior base for finding these solutions and in consequence, facilitates the decision-making process. This paper presents how SMO has been applied for system improvement analysis in a Swedish Emergency Department (ED). A significant number of input variables, constraints and objectives were considered when defining the optimization problem. As a result of the project, the decision makers were provided with a range of optimal solutions which reduces considerably the length of stay and waiting times for the ED patients. SMO has proved to be an appropriate technique to support healthcare system design and improvement processes. A key factor for the success of this project has been the involvement and engagement of the stakeholders during the whole process.
3.	Stråhlman, Christian, et al. (författare) Negative-ion/positive-ion coincidence spectroscopy with a novel spectrometer 2015 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
4.	Espinoza-Andaluz, Mayken, et al. (författare) Applicability of the lattice Boltzmann method to determine the ohmic resistance in equivalent resistor connections 2017 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 936:1 Tidskriftsartikel (refereegranskat)abstract Knowing the ohmic resistance in the materials allow to know in advance its electrical behavior when a potential difference is applied, and therefore the prediction of the electrical performance can be achieved in a most certain manner. Although the Lattice Boltzmann method (LBM) has been applied to solve several physical phenomena in complex geometries, it has only been used to describe the fluid phase, but applicability studies of LBM on the solid-electric-conducting material have not been carried out yet. The purpose of this paper is to demonstrate the accuracy of calculating the equivalent resistor connections using LBM. Several series and parallel resistor connections are effected. All the computations are carried out with 3D models, and the domain materials are designed by the authors.
5.	Folsom, B., et al. (författare) Approximating nonlinear forces with phase-space decoupling 2017 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 874:1 Tidskriftsartikel (refereegranskat)abstract Beam tracking software for accelerators typically falls into two categories: fast envelope simulations limited to linear beam optics, and slower multiparticle simulations that can model nonlinear effects. To find a middle ground between these approaches, we introduce virtual coordinates in position and momentum which have a cross-dependency (i.e. p∗ = f (x 0) where x 0 is an initial position and p∗ is a virtual projection of momentum onto the position axis). This technique approximates multiparticle simulations with a significant reduction in calculation cost.
6.	Joshi, N., et al. (författare) MEMS Based Micro Aerial Vehicles 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 757:1 Konferensbidrag (refereegranskat)abstract Designing a flapping wing insect robot requires understanding of insect flight mechanisms, wing kinematics and aerodynamic forces. These subsystems are interconnected and their dependence on one another affects the overall performance. Additionally it requires an artificial muscle like actuator and transmission to power the wings. Several kinds of actuators and mechanisms are candidates for this application with their own strengths and weaknesses. This article provides an overview of the insect scaled flight mechanism along with discussion of various methods to achieve the Micro Aerial Vehicle (MAV) flight. Ongoing projects in Chalmers is aimed at developing a low cost and low manufacturing time MAV. The MAV design considerations and design specifications are mentioned. The wings are manufactured using 3D printed carbon fiber and are under experimental study. © Published under licence by IOP Publishing Ltd.
7.	Maercker, Matthias, 1979 (författare) ALMA observations of the not-so detached shell around the carbon AGB star R Sculptoris 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 728:2, s. Aricle no. 022006- Konferensbidrag (refereegranskat)abstract I present our ALMA observations of the CO emission around the carbon AGB star R Sculptoris. The data reveal the known detached shell and a previously unknown, binary induced, spiral shape. The observations confirm a formation of the shell during a thermal pulse about 2300 years ago. The full analysis of the ALMA data shows that the shell around R Scl in fact is entirely filled with molecular gas, and hence not as detached as previously thought. This has implications for the mass-loss rate evolution immediately after the pulse, indicating a much higher mass-loss rate than previously assumed. Comparing the ALMA images to our optical observations of polarised, dust scattered light, we further show that the distributions of the dust and gas coincide almost perfectly, implying a common evolution of the dust and gas, and constraining the wind-driving mechanism. The mass-loss process and amount of mass lost during the thermal pulse cycle affect the chemical evolution of the star, its lifetime on the AGB, and the return of heavy elements to the ISM. New high-resolution ALMA observations constrain the parameters of the binary system and the inner spiral, and will allow for a detailed hydrodynamical modelling of the gas and dust during and after the last thermal pulse. Our results present the only direct measurements of the thermal pulse evolution currently available. They greatly increase our understanding of this fundamental period of stellar evolution, and the implications it has for the chemical evolution of evolved stars, the ISM, and galaxie.
8.	Mantulnikovs, K., et al. (författare) Neutron guide shielding for the BIFROST spectrometer at ESS 2016 Ingår i: VI European Conference On Neutron Scattering (ECNS2015). - : IOP Publishing. ; 746:1 Konferensbidrag (refereegranskat)abstract We report on the study of fast-neutron background for the BIFROST spectrometer at ESS. We investigate the effect of background radiation induced by the interaction of fast neutrons from the source with the material of the neutron guide and devise a reasonable fast, thermal/cold neutron shielding solution for the current guide geometry using McStas and MCNPX. We investigate the effectiveness of the steel shielding around the guide by running simulations with three different steel thicknesses. The same approach is used to study the efficiencies of the steel wall a flat cylinder pierced by the guide in the middle and the polyethylene layer. The final model presented here has a 3 cm thick steel shielding around the guide, 30 cm of polyethylene around the shielding, two 5 mm thick B4C layers and a steel wall at position Z = 38 m, being 1 m thick and 10 m in radius. The final model finally proves that it is sufficient to bring the background level below the cosmic neutron rate, which defines an order of magnitude of the lowest obtainable background in the instruments.
9.	Nystedt, Fredrik (författare) On the Use of Risk Concepts in Fire Safety Engineering 2018 Ingår i: 3rd European Symposium on Fire Safety Science 12–14 September 2018, Nancy, France. - : IOP Publishing. - 1742-6588. ; 1107 Konferensbidrag (refereegranskat)abstract Design for fire safety may be carried out by two generic approaches - a set of prescriptive rules or by a performance-based approach where analytical tools are used to verify fire safety towards a set of functional requirements and performance criteria given by the building code. Normally, these two methods are mixed when design fire safety within a building. The option to apply fire safety engineering to the design of buildings has been available during the last 20 to 40 years, depending on which aspect of fire safety being considered. Still, the fire protection of a building too often relies on general recommendations rather than scientifically-based solutions, due to a lack of standardised verification methods, acceptance criteria and procedures to ensure high quality fire safety design. The concept of risk, i.e. the combination of the probability of a fire and a quantified measure of its consequence, has been thoroughly investigated in several fire safety engineering applications over the last decades. Although there are techniques available that allow designers to evaluate fire risks, risk acceptance criteria are missing in general. Structural fire safety design is the exemption having defined target reliabilities. Although these criteria only address the likelihood of collapse of structural element and not explicitly the characteristics of the failure. Structural elements can be provided with fire resistance to control the spread of fire or to prevent structural collapse, or both and it is not uncommon to perform trade-offs between passive and active fire protection systems. But, very little effort has previously been made to understand the fundamental differences between these systems regarding their reliability and failure modes. Performance-based design of structural elements uses a heat exposure model to quantify the thermal load of the fire. The thermal load is characterised by the fire load (duration) and the intensity (air supply). Characteristic values of the fire load are found in various sources and commonly given in the building code, which ought to be used when designing for fire safety. A probabilistic approach was introduced in the 1980s where the probability of fire is expressed as a function of the probability of fire occurrence, the probability of a flashover and the probability of failure given a fully developed fire. Thus, the target probability of failure could be achieved by applying safety measures that alters the probability of any of these events. Currently, fire sprinklers do allow for a reduction in design fire load, but not other active safety system can be considered explicitly. Passive as well as active system for fire safety could both be considered as appropriate provisions to achieve sufficient safety. Even though there are support of trade-offs between passive and active provisions, current regulations, guidance as well as practise do not treat the different aspect of risk related to these systems. By only considering the probability of collapse, the design could deviate from overall societal requirements on avoiding catastrophes or principles of robustness stating that consequences should not be disproportionate to their cause. Traditionally, passive systems are assumed more robust. These findings are probably related to the concepts where target reliabilities are evaluated as the system is designed. Sprinklers are, on the other hand, assigned a probability of successful operation based on decades of statistics. This is an unfair comparison between the systems as a properly design sprinkler system always would prevent a fully developed fire, thus requiring no specific fire resistance on separating and structural elements. Naturally, this is not the path forward as the failure modes of both types of system must be treated and understood. Active systems could be argued to be more forgiven as the they do not care what mistakes are made to cause a fire, neither do they care if occupants act as planed or not. Passive systems are more sensitive to building use when e.g. doors are kept open. Future performance criteria and risk acceptance criteria should not focus solely on probabilities. Emphasis must be put on establish criteria that measure the risk of the unwanted event considering type of initiating event, number of barriers, expected consequence, possibility of damage control, etc. Not until such criteria are available the full potential of performance-based fire safety design cannot be utilised.
10.	Rodriguez, D. Martin, et al. (författare) How to polarise all neutrons in one beam : a high performance polariser and neutron transport system 2016 Ingår i: VI European Conference On Neutron Scattering (ECNS2015). - : IOP Publishing. ; 746:1 Konferensbidrag (refereegranskat)abstract Polarised neutron beams are used in disciplines as diverse as magnetism, soft matter or biology. However, most of these applications often suffer from low flux also because the existing neutron polarising methods imply the filtering of one of the spin states, with a transmission of 50% at maximum. With the purpose of using all neutrons that are usually discarded, we propose a system that splits them according to their polarisation, flips them to match the spin direction, and then focuses them at the sample. Monte Carlo (MC) simulations show that this is achievable over a wide wavelength range and with an outstanding performance at the price of a more divergent neutron beam at the sample position.
11.	Rossander, Morgan, 1981-, et al. (författare) Frequency analysis of tangential force measurements on a vertical axis wind turbine 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. Konferensbidrag (refereegranskat)abstract This paper presents experimental results of the torque ripple obtained from a three bladed 12 kW experimental H-rotor prototype. The measurements are performed by means of load cells installed on the base of the struts and by electrical measurements on the generator. The resulting torques are analysed in terms of frequency spectrum and order spectrum (synchronized with rotation). The measurements are compared to aerodynamic simulations of the turbine. The expected large torque ripple at three times the rotational speed (3 p) is only weakly represented at the hub and in the generator. This suggests that the system is filtering the ripple and/or that the simulations are overestimating the 3 p component. The torque ripple loads on the drive train are therefore lower than anticipated. Even if highly attenuated, most of the low frequencies correlating to aerodynamics are still represented in the generator electrical torque. Given a certain baseline, this opens for possible online monitoring of unbalances in the turbine by electrical measurements.
12.	Varvarezos, Lazaros, et al. (författare) Intensity-dependent near-threshold ionization of Kr in the vacuum-uv 2019 Ingår i: International Conference on Spectral Lines Shapes. - : IOP Publishing. - 1742-6588. ; 1289 Konferensbidrag (refereegranskat)abstract In this work, we present measurements of the intensity-dependent photoelectron spectrum of Kr irradiated by the FLASH FEL tuned to a photon energy of 25.8 eV. Intensity dependent photoelectron spectra were obtained with the aid of a Velocity Map Imaging (VMI) spectrometer. As the FEL photon energy is close to threshold, two photon sequential double ionization is favoured. The number of open channels is kept to a minimum and leading to a simple description of the process.
13.	Andersen, K. H., et al. (författare) A Proposal for a Next Generation European Neutron Source 2016 Ingår i: VI European Conference On Neutron Scattering (ECNS2015). - : IOP Publishing. ; 746:1 Konferensbidrag (refereegranskat)abstract We argue that it is not too early to begin the planning process for a next generation neutron source for Europe, even as the European Spallation Source is being constructed. We put forward three main arguments. Firstly, nowadays the period between the first scientific concept of a new facility being proposed and its actual realisation is approaching half a century. We show evidence for this. Secondly, there is a straightforward development of the short pulse/long pulse spallation concepts that will deliver gains in neutron brightness of more than a factor 30 over what the ESS will soon deliver and provide the optimum balance between resolution and intensity. We describe our concept, which is a spallation source where the proton pulse length is matched to the moderating time of slow neutrons. Thirdly, when we look at our colleagues in astronomy and high energy physics, we see that they have a totally different, more global and more ambitious approach to the coming generations of large facilities. We argue that it is time for the neutron community not simply to rest upon its laurels and take what is given but to be proactive..
14.	Barillot, T., et al. (författare) Attosecond time delays in C-60 valence photoemissions at the giant plasmon 2015 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112074-112074 Konferensbidrag (refereegranskat)abstract We perform time-dependent local density functional calculations of the time delay in C-60 HOMO and HOMO-1 photoionization at giant plasmon energies. A semiclassical model is used to develop further insights.
15.	Benedek, Hunor, et al. (författare) Strategies for quality assurance of intensity modulated radiation therapy 2015 Ingår i: 8TH INTERNATIONAL CONFERENCE ON 3D RADIATION DOSIMETRY (IC3DDOSE). - : Institute of Physics (IOP). ; 573, s. 012015-012015 Konferensbidrag (refereegranskat)abstract In late 2011 The Swedish Society of Radiation Physics formed a working group to concentrate on the Quality Assurance of modern radiation therapy techniques. The given task was to identify and summarise the different QA strategies in Sweden and also the international recommendations. This was used to formulate recommendations for practical guidelines within Sweden. In this paper a brief summery of the group's work is presented. All the Swedish radiation therapy centres do a pre treatment verification measurement as QA for every new IMRT and VMAT plan. Physicists do it and they believe it to be time consuming. A general standpoint from all the centres was that new guidelines and legislation is needed to allow QA that does not require a measurement. Based on various international publications and recommendations the working group has presented two strategies, one where all new plans are checked through measurement and one where no measurement is needed. The measurement-based strategy is basically the same as the one used today with an extended machine QA part. The other presented strategy is process oriented where all the different parts of the treatment chain are checked separately. The final report can be found in Swedish on http://www.radiofysik.org.
16.	Blanco, J. A., et al. (författare) Low energy spin wave excitations in amplitude modulated magnetic structure of PrNi2Si2 2015 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 663, s. 012010-012010 Konferensbidrag (refereegranskat)abstract Inelastic neutron scattering (INS) experiments and random phase approximation calculations have been used to investigate the low energy spin wave excitations in PrNi2Si2. The modulated magnitude of the ordered magnetic moments of Pr3+ ions implies that the associate, longitudinally polarized magnetic excitations are more intense and dispersive than the usual transverse spin waves. Within the random phase approximation the results are in good overall agreement with the predictions made by the model determined previously from the paramagnetic excitations. The most unusual observation is the well defined amplitude mode detected close to the magnetic Bragg point existing simultaneously with the phason mode. At low energies, an extra mode is observed to hybridize with the magnetic phasons in the neighborhood of the magnetic Brillouin zone center. A magnetoelastic interaction between the magnetic excitations and the longitudinal phonons is able to explain part of the disturbances, but it is concluded that the extra mode must be of some other, unknown origin.
17.	Boulet, Pascal, et al. (författare) Proceedings of the 3rd European Symposium on Fire Safety Science 2018 Ingår i: 3rd European Symposium on Fire Safety Science. - : IOP Publishing. - 1742-6588. ; 1107 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
18.	Bournas, Iason, et al. (författare) Relation between occupant perception of brightness and daylight distribution with key geometric characteristics in multi-family apartments of Malmö, Sweden 2019 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 1343 Tidskriftsartikel (refereegranskat)abstract Focusing on subjective evaluations of daylight conditions, the present paper explores the relation between room geometric characteristics and perceived brightness and daylight distribution in residential spaces. The study was conducted in 35 apartments consisting of 105 different rooms in the city of Malmö, and selected with respect to typical Swedish architectural building typologies. Questionnaires were distributed by mail to participants, and apartments were surveyed to deduct key geometric characteristics. Results include a reliability analysis of the utilized questionnaire and a correlation study that showed the prevalence of both window size and number as key factors relating to perceived daylight conditions.
19.	Bäck, S. Å.J., et al. (författare) 4D dosimetry and motion management in clinical radiotherapy 2019. - 1 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1305 Konferensbidrag (refereegranskat)abstract Many novel modulated radiation treatment techniques are sensitive to patient motion which may degrade the dose distribution considerably. As there may be a simultaneous movement of the tumour and treatment machine, undesired heterogeneities in the dose distribution can be resulted. Methods to estimate the dosimetric effect of motion and treatment deliveries for both photons and protons are needed. We have recently studied Hodgkin's lymphoma, liver and left sided breast cancer cases and developed tools to be able to simulate simultaneous organ movement and treatment delivery. Furthermore, it is of great importance to validate potential simulations in a realistic quality control set-up, ideally including a complete dosimetry volume and movement/deformation (4D). Radiation sensitive deformable gels have the potential to meet this dosimetry challenge owing to the unique 3D characteristic to form both phantom and detector in one volume. Multi-array detectors together with a moving platform and a realistic object trajectory is an alternative to evaluate the clinical setting. The evaluation could then in principle be done on-line. Gel/plastic 3D dosimeters have the potential to also be irradiated during motion in a similar matter but have to be read-out post irradiation.
20.	Carvalho, F, et al. (författare) Tetraquark Production in Hadronic Collisions 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 706:Section 4 Tidskriftsartikel (refereegranskat)abstract We develop a formalism to study the tetraquark production in hadronic collisions. We focus on double parton scattering and formulate a version of the color evaporation model for the production of the T4c tetraquark, a state composed by the quarks. We find that the production cross section grows rapidly with the collision energy and the T4c might be observable at LHC energies.
21.	Catovic, Lamija, et al. (författare) A survey on the factors affecting horizontal assisted evacuation in hospitals 2018 Ingår i: 3rd European Symposium on Fire Safety Science 12–14 September 2018, Nancy, France. - : IOP Publishing. - 1742-6588. ; 1107 Konferensbidrag (refereegranskat)abstract This paper presents the results of a survey on assisted evacuation conducted with 120 hospital staff members in Sweden. Staff members included people with different roles in the hospital (e.g. doctors, nurses, department heads, etc.). The survey consisted of a questionnaire aiming at investigating the factors which affect assisted evacuation in hospitals and the current status of assisted evacuation training in Sweden. The survey included a list of questions concerning factors which were previously identified through a literature review and that they may affect the effectiveness of horizontal assisted evacuation in hospitals. Hospital staff had to evaluate the importance of these factors through a Likert-scale questionnaire. Three factors were identified in the survey by hospital staff as the most important in horizontal assisted evacuation, namely 1) coordination/collaboration between staff, 2) the patient need for assistance and 3) Training on evacuation routines. According to the questionnaire results, occupants who are in need for life-sustaining equipment can be the most difficult to evacuate. Results also show that only 52% of respondents had ever taken part into an evacuation drill and 50% had practiced how to handle evacuation aid tools needed for assisted evacuation, with rescue mattresses being the most used evacuation aid. 78% of respondents were aware of the person responsible for arranging tasks in case of an emergency situation.
22.	Christiansen, Peter (författare) Event-Shape Engineering and Jet Quenching 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 736:1 Tidskriftsartikel (refereegranskat)abstract Event-Shape Engineering (ESE) is a tool that enables some control of the initial geometry in heavy-ion collisions in a similar way as the centrality enables some control of the number of participants. Utilizing ESE, the path length in and out-of plane can be varied while keeping the medium properties (centrality) fixed. In this proceeding it is argued that this provides additional experimental information about jet quenching. Finally, it is suggested that if ESE studies are done in parallel for light and heavy quarks one can determine, in a model independent way, if the path-length dependence of their quenching differs.
23.	Curceanu, C., et al. (författare) The kaonic atoms research program at DAΦNE : Overview and perspectives 2018 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1138:1 Tidskriftsartikel (refereegranskat)abstract The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms is, in this context, a unique tool to obtain precise information on this interaction. The energy shift and broadening of the lowest-lying states of such atoms, induced by the kaon-nucleus strong interaction, can be determined with high precision from atomic X-ray spectroscopy. This experimental method provides unique information to understand the low energy kaon-nucleus interaction at threshold. The lightest atomic systems, kaonic hydrogen and kaonic deuterium, deliver the isospin-dependent kaon-nucleon scattering lengths. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of kaonic deuterium, were carried out by the SIDDHARTA collaboration at the DAΦNE electron-positron collider of LNF-INFN, by combining the excellent quality kaon beam delivered by the collider with new experimental techniques, as fast and precise X-ray detectors: Silicon Drift Detectors. The measurement of kaonic deuterium will be realized in the near future by SIDDHARTA-2, a major upgrade of SIDDHARTA. In this paper an overview of the main results obtained by SIDDHARTA together with the future plans, are given.
24.	Damtie, Fikeraddis A., et al. (författare) Time dependent study of multiple exciton generation in nanocrystal quantum dots 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 696:1 Tidskriftsartikel (refereegranskat)abstract We study the exciton dynamics in an optically excited nanocrystal quantum dot. Multiple exciton formation is more efficient in nanocrystal quantum dots compared to bulk semiconductors due to enhanced Coulomb interactions and the absence of conservation of momentum. The formation of multiple excitons is dependent on different excitation parameters and the dissipation. We study this process within a Lindblad quantum rate equation using the full many-particle states. We optically excite the system by creating a single high energy exciton ESX in resonance to a double exciton EDX. With Coulomb electron-electron interaction, the population can be transferred from the single exciton to the double exciton state by impact ionisation (inverse Auger process). The ratio between the recombination processes and the absorbed photons provide the yield of the structure. We observe a quantum yield of comparable value to experiment assuming typical experimental conditions for a 4 nm PbS quantum dot.
25.	Delerue, N., et al. (författare) A Massive Open Online Course on Particle Accelerators 2018. - 9 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1067 Konferensbidrag (refereegranskat)abstract The TIARA (Test Infrastructure and Accelerator Research Area) project funded by the European Union 7th framework programme made a survey of provision of education and training in accelerator science in Europe. This survey highlighted the need for more training opportunities targeting undergraduate-level students. This need is now being addressed by the European Union H2020 project ARIES (Accelerator Research and Innovation for European Science and Society) via the preparation of a Massive Open Online Course (MOOC) on particle accelerator science and engineering. We present here the current status of this project, the main elements of the syllabus, how it will be delivered, and the schedule for providing the course.
26.	Dijulio, Douglas D., et al. (författare) Benchmarking Geant4 for spallation neutron source calculations 2016 Ingår i: VI European Conference On Neutron Scattering (ECNS2015). - : IOP Publishing. ; 746:1 Konferensbidrag (refereegranskat)abstract Geant4 is becoming increasingly used for radiation transport simulations of spallation neutron sources and related components. Historically, the code has seen little usage in this field and it is of general interest to investigate the suitability of Geant4 for such applications. For this purpose, we carried out Geant4 calculations based on simple spallation source geometries and also with the the European Spallation Source Technical Design Report target and moderator configuration. The results are compared to calculations performed with the Monte Carlo N Particle extended code. The comparisons are carried out over the full spallation neutron source energy spectrum, from sub-eV energies up to thousands of MeV. Our preliminary results reveal that there is generally good agreement between the simulations using both codes. Additionally, we have also implemented a general weight-window generator for Geant4 based applications and present some results of the method applied to the ESS target model.
27.	Dijulio, Douglas D., et al. (författare) Characterization of the radiation background at the Spallation Neutron Source 2016 Ingår i: VI European Conference On Neutron Scattering (ECNS2015). - : IOP Publishing. ; 746:1 Konferensbidrag (refereegranskat)abstract We present a survey of the radiation background at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, TN, USA during routine daily operation. A broad range of detectors was used to characterize primarily the neutron and photon fields throughout the facility. These include a WENDI-2 extended range dosimeter, a thermoscientific NRD, an Arktis He-4 detector, and a standard Nal photon detector. The information gathered from the detectors was used to map out the neutron dose rates throughout the facility and also the neutron dose rate and flux profiles of several different beamlines. The survey provides detailed information useful for developing future shielding concepts at spallation neutron sources, such as the European Spallation Source (ESS), currently under construction in Lund, Sweden.
28.	Edvardsson, Anneli, et al. (författare) Verification of motion induced thread effect during tomotherapy using gel dosimetry 2015 Ingår i: 8th International Conference on 3D Radiation Dosimetry (IC3DDOSE). - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 573, s. 012048-012048 Konferensbidrag (refereegranskat)abstract The purpose of the study was to evaluate how breathing motion during tomotherapy (Accuray, CA, USA) treatment affects the absorbed dose distribution. The experiments were carried out using gel dosimetry and a motion device simulating respiratory-like motion (HexaMotion, ScandiDos, Uppsala, Sweden). Normoxic polyacrylamide gels (nPAG) were irradiated, both during respiratory-like motion and in a static mode. To be able to investigate interplay effects the static absorbed dose distribution was convolved with the motion function and differences between the dynamic and convolved static absorbed dose distributions were interpreted as interplay effects. The expected dose blurring was present and the interplay effects formed a spiral pattern in the lower dose volume. This was expected since the motion induced affects the preset pitch and the theoretically predicted thread effect may emerge. In this study, the motion induced thread effect was experimentally verified for the first time.
29.	Espinoza-Andaluz, Mayken, et al. (författare) A suitable width-size of a channel flow for obtaining the velocity profiles by using the Lattice Boltzmann method 2018 Ingår i: International Conference on Mathematical Modelling in Physical Sciences 27–31 October 2018, Moscow, Russian Federation. - : IOP Publishing. - 1742-6588. ; 1141 Konferensbidrag (refereegranskat)abstract The Poiseuille flow has been widely analyzed from analytical and experimental point of view with different approaches. Although the Lattice Boltzmann method (LBM) has proven to be a suitable tool for mimicking the fluid flow behavior not only for complex but also for simple geometries such as lid driven cavity and channel flow, the required computational size or characteristic length to obtain an acceptable approximation of the described physical phenomena has to be defined. The aim of this study is to evaluate the impact of considering different width-sizes of a channel flow when the velocity profiles are obtained. Channel flow with several width-sizes are evaluated while keeping the Re and aspect ratio as constant.
30.	Espinoza Andaluz, Mayken, et al. (författare) Potential of Lattice Boltzmann method to determine the ohmic resistance in porous materials 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 738:1 Tidskriftsartikel (refereegranskat)abstract The lattice Boltzmann method (LBM) is a suitable tool for solving transport phenomena that occur in gas- and liquid phases at different length scales, especially when complex geometries such as porous media are involved. However, investigations about applications of LBM in the solid electrical conducting material have not been carried out yet. Since in fuel cells (FCs) the multifunctional layers play an important role during the energy conversion process, and such layers consist of porous material, the ohmic resistance of porous materials represents a crucial characteristic to be studied to predict the internal ohmic losses. The purpose of this paper is to show the feasibility of LBM to determine the ohmic resistance of electrical conducting materials whose dimensions are modified considering the cross-sectional area and length. Characteristics, limitations and recommendations of LBM applied to solid electrical conducting materials calculating the ohmic resistance are presented considering the coupling of the methodology with the Ohm’s Law. Additionally, the behavior of the ohmic resistance for a given porous material is presented.
31.	Fenske, J., et al. (författare) BEER-The Beamline for European Materials Engineering Research at the ESS 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 746:1 Tidskriftsartikel (refereegranskat)abstract The Beamline for European Materials Engineering Research (BEER) will be built at the European Spallation Source (ESS). The diffractometer utilizes the high brilliance of the long-pulse neutron source and offers high instrument flexibility. It includes a novel chopper technique that extracts several short pulses out of the long pulse, leading to substantial intensity gain of up to an order of magnitude compared to pulse shaping methods for materials with high crystal symmetry. This intensity gain is achieved without compromising resolution. Materials of lower crystal symmetry or multi-phase materials will be investigated by additional pulse shaping methods. The different chopper set-ups and advanced beam extracting techniques offer an extremely broad intensity/resolution range. Furthermore, BEER offers an option of simultaneous SANS or imaging measurements without compromising diffraction investigations. This flexibility opens up new possibilities for in-situ experiments studying materials processing and performance under operation conditions. To fulfil this task, advanced sample environments, dedicated to thermo-mechanical processing, are foreseen.
32.	Ferreira, Thiago, et al. (författare) Effect of atrium geometry and reflectance on daylighting in adjacent rooms 2019 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 1343, s. 012167-012167 Tidskriftsartikel (refereegranskat)abstract Atria are implemented in buildings to increase daylight, foster interaction and provide ventilation. However, their implementation can be complex if good daylight is to be achieved. This research proposed an investigation about the atrium parameters that affect daylight conditions in a case study. This evaluation concentrated in the atrium geometry and the wall reflectance values. Overall, the outcomes demonstrated that shifting the atrium from an enclosed to a semi-enclosed one can double the daylight in the atrium adjacent rooms. Moreover, it is possible to achieve better daylight in the adjacent rooms by keeping the same floor area of the building.
33.	Folsom, B., et al. (författare) Beam Dynamics with Covariant Hamiltonians 2018 Ingår i: 9th International Particle Accelerator Conference, IPAC18 29 April to 4 May 2018, Vancouver, B.C., Canada. - : IOP Publishing. - 1742-6588. ; 1067 Konferensbidrag (refereegranskat)abstract We demonstrate covariant beam-physics simulation through multipole magnets using Hamiltonians relying on canonical momentum. Space-charge interaction using the Lienard-Wiechert potentials is also discussed. This method is compared with conventional nonlinear Lie-operator tracking and the TraceWin software package.
34.	Folsom, B., et al. (författare) Beam shaping with 4n-order multipole magnets 2017 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 874:1 Tidskriftsartikel (refereegranskat)abstract A uniformly irradiating beam is beneficial in spallation for preventing irregular wear on the target. For octupoles (n = 4) and higher-order (n = 4N) magnets, passing charged-particle bunches undergo symmetric shaping effects along the x and y axes. Using a Lie-mapping formalism, we illustrate how well Gaussian distributions can be flattened symmetrically in 2D with single, dual-pulse, and RF magnets of 4N order. Incidental shaping effects are also discussed.
35.	Huang, Y. S., et al. (författare) Growth of InAs NWs with controlled morphology by CVD 2017 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 864:1 Tidskriftsartikel (refereegranskat)abstract We report on the growth of single crystal InAs NWs on Si/SiOx substrates by chemical vapor deposition (CVD). By adjusting growth parameters, the diameters, morphology, length and the proportion of superlattice ZB InAs NWs (NWs) can be controlled on a Si/SiOx substrate. Our work provides a low-cost route to grow and phase-engineer single crystal InAs NWs for a wide range of potential applications.
36.	Iablonskyi, D., et al. (författare) Interatomic Coulombic Decay Processes after Multiple Valence Excitations in Ne Clusters 2015 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112067-112067 Konferensbidrag (refereegranskat)abstract We present a comprehensive analysis of autoionization processes in Ne clusters (similar to 5000 atoms) after multiple valence excitations by free electron laser radiation. The evolution from 2-body interatomic Coulombic decay (ICD) to 3-body ICD is demonstrated when changing from surface to bulk Frenkel exciton excitation. Super Coster-Kronig type 2-body ICD is observed at Wannier exciton which quenches the main ICD channel.
37.	Ingesson, Gabriel, et al. (författare) Control of the Low-Load Region in Partially Premixed Combustion 2016. - 1 Ingår i: Journal of Physics: Conference Series : proceedings of 13th International Conference on Motion and Vibration Control (MOVIC 2016) - proceedings of 13th International Conference on Motion and Vibration Control (MOVIC 2016). - : IOP Publishing. ; 744 Konferensbidrag (refereegranskat)abstract Partially premixed combustion (PPC) is a low temperature, direct-injection combustion concept that has shown to give promising emission levels and efficiencies over a wide operating range. In this concept, high EGR ratios, high octane-number fuels and early injection timings are used to slow down the auto-ignition reactions and to enhance the fuel and are mixing before the start of combustion. A drawback with this concept is the combustion stability in the low-load region where a high octane-number fuel might cause misfire and low combustion efficiency. This paper investigates the problem of low-load PPC controller design for increased engine efficiency. First, low-load PPC data, obtained from a multi-cylinder heavy- duty engine is presented. The data shows that combustion efficiency could be increased by using a pilot injection and that there is a non-linearity in the relation between injection and combustion timing. Furthermore, intake conditions should be set in order to avoid operating points with unfavourable global equivalence ratio and in-cylinder temperature combinations. Model predictive control simulations were used together with a calibrated engine model to find a gas-system controller that fulfilled this task. The findings are then summarized in a suggested engine controller design. Finally, an experimental performance evaluation of the suggested controller is presented.
38.	Jimenez-Galan, A., et al. (författare) Phase Measurement of a Fano Resonance Using Tunable Attosecond Pulses 2015 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 635, s. 092137-092137 Konferensbidrag (refereegranskat)abstract We study photoionization of argon atoms close to the 3s(2)3p(6) -> 3s(1)3p(6)4p Fano resonance using an attosecond pulse train and a weak infrared probe field. An interferometric technique combined with tunable attosecond pulses allows us to determine the phase of the photoionization amplitude as a function of photon energy. We interpret the experimental results using an analytical two-photon model based on the Fano formalism and obtain quantitative agreement.
39.	Johansson, Nils (författare) A Case Study of Far-Field Temperatures in Progressing Fires 2018 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; :1107 Tidskriftsartikel (refereegranskat)abstract The non-uniform conditions and potential progression of fires in larger spaces calls for modelling methods extending outside of the traditional compartment fire framework. Even though a handful of studies in the area exist there is still little guidance available on how progressing fires in large enclosures can be modelled. Three different methods to calculate far-field gas temperature in large enclosures are therefore reviewed in this paper with the help of a case study. The three methods used are: the analytical Alpert ceiling jet correlation, the Fire Dynamics Simulator (FDS) and a Multi-Layer Zone (MLZ) model.The enclosure used in the case study is intended to represent a large open space, i.e. an office, warehouse or supermarket. Two different user defined fire scenarios, which represent two progressing fires, are analysed.This is a comparative study and no experimental data is used to evaluate the models. However, it is considered reasonable to believe that FDS gives good predictions since it has shown to predict gas temperatures well in previous validation studies. The MLZ model has not been thoroughly evaluated, but it has been seen to overestimate experimental results slightly in a previous study.The results from FDS and the MLZ model show that there is a temperature distribution (vertical and horizontal) in both fire scenarios, which means that there are non-uniform conditions in the gas layer. The results also indicate that there is a correspondence between the MLZ model and FDS; however, as the heat release rate increase the difference between the models increases. The analytical correlation results in much lower temperature predictions than both FDS and the MLZ model. The main reason for that is that the correlation assumes the flow to be unconfined, which is not the case in this study.The main benefits of the MLZ model is the low computational time (about 1 minute on a laptop computer) compared to FDS (where the computational time was more than two days). Furthermore, the MLZ model provides temperature profiles both horizontally and vertically, which is not the case in conventional zone models.
40.	Karlsson, Daniel, et al. (författare) Effective bias and potentials in steady-state quantum transport : A NEGF reverse-engineering study 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 696:1 Tidskriftsartikel (refereegranskat)abstract Using non-equilibrium Green's functions combined with many-body perturbation theory, we have calculated steady-state densities and currents through short interacting chains subject to a finite electric bias. By using a steady-state reverse-engineering procedure, the effective potential and bias which reproduce such densities and currents in a non-interacting system have been determined. The role of the effective bias is characterised with the aid of the so-called exchange-correlation bias, recently introduced in a steady-state density-functional- theory formulation for partitioned systems. We find that the effective bias (or, equivalently, the exchange-correlation bias) depends strongly on the interaction strength and the length of the central (chain) region. Moreover, it is rather sensitive to the level of many-body approximation used. Our study shows the importance of the effective/exchange-correlation bias out of equilibrium, thereby offering hints on how to improve the description of density- functional-theory based approaches to quantum transport.
41.	Kivimaki, A., et al. (författare) Synchrotron excitation - field ionization studies of high-Rydberg fragments produced after inner-shell ionization of small molecules 2015 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112121-112121 Konferensbidrag (refereegranskat)abstract We have studied the production of neutral high-Rydberg (HR) fragments in small molecules after inner-shell excitation and ionization. Such fragments were ionized using a pulsed electric field and resulting ions were mass-analyzed with an ion time-of-flight (TOF) spectrometer. As an example, the results obtained at the C 1s ionization threshold of the methane molecule will be discussed.
42.	Klementiev, K., et al. (författare) High performance emission spectrometer at Balder/MAX IV beamline 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 712:1 Tidskriftsartikel (refereegranskat)abstract The emission spectrometer at Balder/MAX IV beamline is presented. Its unique features are described. Comparison is given with other types of curved crystals analyzers.
43.	Klementiev, K., et al. (författare) The BALDER Beamline at the MAX IV Laboratory 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 712:1 Tidskriftsartikel (refereegranskat)abstract X-ray absorption spectroscopy (XAS) includes well-established methods to study the local structure around the absorbing element - extended X-ray absorption fine structure (EXAFS), and the effective oxidation number or to quantitatively determine the speciation of an element in a complex matrix - X-ray absorption near-edge structure (XANES). The increased brilliance and intensities available at the new generation of synchrotron light sources makes it possible to study, in-situ and in-operando, much more dilute systems with relevance for natural systems, as well as the micro-scale variability and dynamics of chemical reactions on the millisecond time-scale. The design of the BALDER beamline at the MAX IV Laboratory 3 GeV ring has focused on a high flux of photons in a wide energy range, 2.4-40 keV, where the K-edge is covered for the elements S to La, and the L 3-edge for all elements heavier than Sb. The overall design of the beamline will allow large flexibility in energy range, beam size and data collection time. The other focus of the beamline design is the possibility to perform multi-technique analyses on samples. Development of sample environment requires focus on implementation of auxiliary methods in such a way that techniques like Fourier transform infrared (FTIR) spectroscopy, UV-Raman spectroscopy, X-ray diffraction and/or mass spectrometry can be performed simultaneously as the XAS study. It will be a flexible system where different instruments can be plugged in and out depending on the needs for the particular investigation. Many research areas will benefit from the properties of the wiggler based light source and the capabilities to perform in-situ and in-operando measurements, for example environmental and geochemical sciences, nuclear chemistry, catalysis, materials sciences, and cultural heritage.
44.	Klementiev, K., et al. (författare) XAFSmass : A program for calculating the optimal mass of XAFS samples 2016 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 712:1 Tidskriftsartikel (refereegranskat)abstract We present a new implementation of the XAFSmass program that calculates the optimal mass of XAFS samples. It has several improvements as compared to the old Windows based program XAFSmass: 1) it is truly platform independent, as provided by Python language, 2) it has an improved parser of chemical formulas that enables parentheses and nested inclusion-to-matrix weight percentages. The program calculates the absorption edge height given the total optical thickness, operates with differently determined sample amounts (mass, pressure, density or sample area) depending on the aggregate state of the sample and solves the inverse problem of finding the elemental composition given the experimental absorption edge jump and the chemical formula.
45.	Knöös, T. (författare) 3D dose computation algorithms 2017 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 847:1 Tidskriftsartikel (refereegranskat)abstract The calculation of absorbed dose within patients during external photon beam radiotherapy is reviewed. This includes the modelling of the radiation source i.e. in most cases a linear accelerator (beam modelling) and examples of dose calculation algorithms applied within the patient i.e. the dose engine. For the first part - the beam modelling, the different sources in the treatment head as target, filters and collimators etc are discussed as well as their importance for the photon and electron fluence reaching the patient. The consequences of removing the flattening filter, which several vendors now have made commercially available, is also shown. The pros and cons regarding different dose engines ability to consider density changes within the patient will is covered (type a and b models). Engines covered are, for example, pencil-beam models, collapsed cone superposition/-convolution models and combinations of these, as well as a glimpse on Monte Carlo methods for radiotherapy. The different models' ability to calculate dose to medium (tissue) and or water is. Finally, the role of commissioning data especially measurements in today's model based dose calculation is presented.
46.	Knöös, Tommy (författare) QA procedures needed for advanced RT techniques and its impact on treatment outcome 2015 Ingår i: 8th International Conference on 3D Radiation Dosimetry (IC3DDOSE). - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 573, s. 012001-012001 Konferensbidrag (refereegranskat)abstract The radiotherapy process is reviewed briefly and potential risks or pitfalls are identified. The focus is on modern advanced modalities in radiation therapy such as IMRT, VMAT, gating and tracking and also for the unknown to come. Existing methods, or quality controls (QC), or with better word barriers, are introduced at important steps of process with the purpose of prohibiting errors to continue through the process and thus avoiding an unwanted erroneous irradiation of the patient. The soft branch of quality assurance (QA) such as peer-review is also a major component of today's process and its safety. The importance of knowing your QCs is pointed out. The role of dosimetry method i.e. 3D-dosimetry is reviewed. Staff have to be working with awareness and alertness that can reduce most of the risks. Having comprehensive protocols known by all involved together with well-trained staff at the department with dedicated functions and responsibilities will further reduce the risk for unintended irradiations of patient. Having a well-designed QA system with the appropriate barriers have the possibility of producing high quality radiotherapy, which will also result in better outcome for the patients. The international head and neck trial illustrates very well the importance of accurate radiotherapy.
47.	Koryakin, A. A., et al. (författare) Modeling the formation of InP/GaxIn1-xP axial nanowire heterostructures 2019 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1410:1 Tidskriftsartikel (refereegranskat)abstract A model is developed to depict the formation of InP/GaxIn1-xP axial heterostructures in self-catalyzed GaxIn1-xP nanowires. The composition profiles of the InP/GaxIn1-xP axial heterostructure are calculated taking into account elastic stresses. It is shown that the InP/GaxIn1-xP axial heterojunction width at the growth temperature of 450°C is larger than 12 monolayers for nanowires with the radius larger than 10 nm. Also, the comparison with GaxIn1-xAs system is performed and reveals that the InP/GaxIn1-xP axial heterojunction width is approximately two times smaller than the InAs/GaxIn1-xAs axial heterojunction width.
48.	Krelina, Michal, et al. (författare) Study of Drell-Yan pair production on nuclear targets 2017 Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 832:1 Tidskriftsartikel (refereegranskat)abstract Drell-Yan pair production off nuclei is an ideal tool to test the cold nuclear effects occurring before a hard collision since no interaction in the final state is expected, neither energy loss or absorption. We present for the first time a comprehensive study of the nucleus-to-nucleon production ratio (the nuclear modification factor) within the color dipole approach using the Green function formalism which naturally incorporates for the color transparency and quantum coherence effects. We study a different onset of nuclear shadowing in various kinematical regions. At large values of the Feynman variable xF and dilepton invariant mass M we include also a suppression factor due to restrictions caused by the energy conservation induced by multiple initial state interactions (ISI effects). We present a variety of predictions for the nuclear suppression as a function of xF and M that can be verified by experiments at RHIC and LHC. The mixing of coherence effects with ISI effects can be eliminated going to large values of the dilepton invariant mass. Then predictions for the nuclear suppression is a direct manifestation for the onset of net ISI effects that can be verified by the future measurements.
49.	Kristensson, Elias, et al. (författare) Quantification of the absorbed dose in 3D by means of advanced optical diagnostics based on structured illumination 2015 Ingår i: 8th International Conference on 3D Radiation Dosimetry (IC3DDOSE). - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 573, s. 012010-012010 Konferensbidrag (refereegranskat)abstract The purpose of this study was to present a novel optical diagnostic tool that corrects for undesired contribution of multiply scattered light, thus opening up for e.g. quantitative optical CT measurements of opaque samples. The approach is based on a technique called Structured Illumination (SI), which is commonly employed within microscopic imaging to enhance the depth-resolution. The concept of SI applies for many types of source-detector arrangements and the configuration employed in this paper relies on side-scattering detection. A nPAG polymer gel phantom was irradiated using 6 MV beam. Three-dimensional information was obtained by translating the sample perpendicular to the direction of light, thus sequentially probing different sections. These were then stacked together to form a 3D representation of the sample. By altering the polarization of the laser light during the data acquisition it was discovered that the aggregates responsible for the scattering of light followed Rayleigh scattering, implying that their individual sizes are smaller than, or in the order of, 500 nm.
50.	Leshchenko, E. D., et al. (författare) Nucleation-limited composition of Al 1-x In x As nanowires 2019 Ingår i: 20th Russian Youth Conference on Physics of Semiconductors and Nanostructures, Opto- and Nanoelectronics 26–30 November 2018, St. Petersburg, Russian Federation. - : IOP Publishing. - 1742-6588. ; 1199 Konferensbidrag (refereegranskat)abstract Despite the great advances in synthesis of III-V ternary nanowires over the past decade, there is a lack of understanding and detailed information about Al 1-x In x As nanowire growth. Recently, we have developed an analytical approach for understanding the composition of ternary nanowires nucleating from a quaternary liquid melt. Herein, we use our model to describe the formation of Al 1-x In x As nanowires and tuning their composition within the nucleation-limited regime of nanowire growth via the vapor-liquid-solid mechanism. In particular, we examine the influence of growth temperature and the total concentrations of group III elements on the liquid-solid composition dependence. The obtained results may be useful for Al 1-x In x As nanowire growth.

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