The Standard Model has been greatly successful in predicting the laws that govern our universe. Yet there are still seemingly missing pieces to the model. Detector development plays a crucial role in advancing our understanding of particle physics and helps answer some of the most pressing questions in the field, such as the nature of dark matter and why a matter-antimatter asymmetry is observed. This thesis has covered the work of developing detectors for two different experiments. The HIBEAM/NNBAR experimental program will be a search after neutron-sterile neutron and neutron-antineutron oscillations housed in the the European Spallation Source (ESS) in Lund, Sweden. The experiment will reach unprecedented sensitivity for free-neutron searches, surpassing the last the oscillation time limit by 3 orders of magnitude. This thesis presents an overview of the experimental goals and the opportunities afforded by the ESS infrastructure. The primary work for this thesis has been the design, simulation and construction of a prototype calorimeter for NNBAR stage of the experiment, which is presented here. The ATLAS experiment is currently undergoing upgrades to meet the requirements of the high-luminosity, high-radiation environment at the HL-LHC. This thesis provides an overview of the LHC and the ATLAS experiment, with special focus on the hadronic Tile calorimeter. TileCal will be upgraded to provide full granularity data at the lowest trigger level of the upgraded ATLAS trigger and data acquisition system. The work presented here focuses on TileCal upgrades to Daughterboard (DB), the interlink board responsible for the management of on- and off-detector data transmission. This work has been primarily focused on the design and fabrication of two printed circuit boards to test the implementation of a commercial, radiation-hardened FPGA in the upgraded DB design. The FPGA will control access to remote control JTAG in the DB Xilinx FPGA interface.

The maintenance of medical devices is of great importance to ensure that the devices are stable, well-functioning, and safe to use. The current method of maintenance, which is called preventive maintenance, has its advantages but can be problematic both from an operators’ and a manufacturers’ side. Developing a model that will predict failure in anesthesia machines can be of great use for the manufacturer, the customers, and the patients. This thesis sets to examine the possibility of creating a predictive maintenance model for anesthesia machines by utilizing device data and machine learning. This thesis also investigates the influence of the data on the model performance and compare different lag sizes and future horizons to model performance. The time-series data collected came from 87 unique devices and a specific test was chosen to be the output variable of the model. A whole pipeline was created, which included pre-processing of the data, feature engineering, and model development. Feature extraction was done on the time series data, with the help of a library called tsfresh, which transformed time series characteristics into features that would enable supervised learning. Two models were developed: logistic regression and XGBoost. The logistic regression model acted as a baseline model and the result of its performance was as expected, quite poor. The XGBoost yielded an AUCPR score of 0.21 on the full dataset and 0.32 on a downsampled dataset. Although a quite low score, it was surprisingly high considering the extreme class imbalance that existed in the dataset. No clear pattern was found between the lag sizes and future horizons with the model performance. Something that could be seen was that the data imbalance had a great impact on the model performance, which was discovered when the downsampled dataset with less class imbalance yielded a higher AUCPR score. / Underhållet av medicintekniska produkter är mycket viktigt för att säkerställa att enheterna är stabila, välfungerande och säkra att använda. Den nuvarande underhållsmetoden, som kallas förebyggande underhåll, har sina fördelar men kan vara problematisk både från operatörens och tillverkarsidan. Att utveckla en modell som förutsäger fel i anestesimaskiner kan vara till stor nytta för tillverkaren, kunderna och patienterna. Denna avhandling syftar till att undersöka möjligheten att skapa en förutsägbar underhållsmodell för anestesimaskiner genom att använda enhetsdata och maskininlärning. Denna avhandling undersöker också påverkan av data på modellprestanda och jämför olika fördröjningsstorlekar och framtida horisonter med modellprestanda. Tidsseriedata som samlats in kom från 87 unika enheter och ett specifikt test valdes för att vara modellens outputvariabel. En hel pipeline skapades, som inkluderade förbehandling av data, funktionsteknik och modellutveckling. Funktionsextraktion gjordes på tidsseriedata med hjälp av ett bibliotek som heter tsfresh, som förvandlade tidsserieegenskaper till funktioner som skulle möjliggöra övervakat lärande. Två modeller utvecklades: logistisk regression och XGBoost. Den logistiska regressionsmodellen fungerade som en basmodell och resultatet av dess prestanda var som förväntat ganska dåligt. XGBoost gav en AUCPR-poäng på 0,21 på hela datamängden och 0,32 på en nedmonterad datamängd. Även om det var en ganska låg poäng, var det överraskande högt med tanke på den extrema klassobalansen som fanns i datasetet. Inget tydligt mönster hittades mellan fördröjningsstorlekarna och framtida horisonter med modellprestanda. Något som kunde ses var att dataobalansen hade stor inverkan på modellens prestanda, vilket upptäcktes när den nedprovade datamängden med mindre obalans i klassen gav en högre AUCPR-poäng.

Rare earth-doped upconversion nanoparticles can emit light with various wavelength from ultraviolet to infrared when excited by near-infrared light. The superior properties including long luminescence lifetime, narrow emission spectra, low toxicity and high chemical stability makes it a promising optical material in bioimaging and other applications. This thesis measured and compared the optical properties of NaYF4:Yb-Er and NaYF4:Yb-Mn. with combined AFM-PL measurement applied to identify the single crystal. In addition, the polarization and temperature dependence measurement were also implemented to compare the characteristics. Finally, the errors that may be introduced to the measurement are analysed, and improvements and research plan are proposed and discussed. / Sällsynta jorddopade uppkonverteringsnanopartiklar kan avge ljus med olika våglängder från ultraviolett till infrarött när de exciteras av nära-infrarött ljus. De överlägsna egenskaperna inklusive lång luminescenslivslängd, smala emissionsspektra, låg toxicitet och hög kemisk stabilitet gör det till ett lovande optiskt material i bioavbildning och andra applikationer. Denna avhandling mätte och jämförde de optiska egenskaperna hos NaYF4:Yb-Er och NaYF4:Yb-Mn. med kombinerad AFM-PL-mätning tillämpad för att identifiera enkristallen. Dessutom implementerades polarisations- och temperaturberoendemätning för att jämföra egenskaperna. Slutligen analyseras de fel som kan komma att införas i mätningen och förbättringar och forskningsplan föreslås och diskuteras.

The Yankee cylinder is used in most of Metso Paper's machines. It is used in the drying and creping process. Since the outcome of these processes largely affect the paper's final quality it is important that the Yankee cylinder behaves in a controlled fashion. One important parameter affecting the behaviour of the Yankee cylinder is its surface temperature. The objective of this thesis was to search for and evaluate methods for measuring the surface temperature of a Yankee cylinder during operation. Metso Paper is looking for a method having an accuracy of ΔT = 1°C, a response time of t<10 ms, and being portable. Three different instruments were tested during the thesis: Thermophone, a contact measurement device currently used by Metso Paper. RAYNGER MX4, a pyrometer from Raytek. FLIR P640, a thermographic camera with a 640x480 focal plane array from FLIR. The instruments were tested by performing measurements on Metso Paper's pilot machine in Karlstad during operation. The measurements revealed drawbacks for all three instruments. The biggest drawbacks of the Thermophone was its response time, t~5 min, and its dependence on the frictional heating of the teflon cup. The frictional heating causes the measured temperature to increase even after 15 min making it hard to know when to stop the measurement. How much the frictional heating affects the measured temperature was difficult to analyse, making it a suggestion for future studies. The biggest drawback of the pyrometer and the thermographic camera is the measurement error due to emissivity errors. Since the Yankee cylinder have a varying surface finish the emissivity varies a lot along the surface introducing temperature errors as large as ΔT=30°C. Two methods that claim to be emissivity independent were investigated; double-band and gold cup pyrometers. Double-band pyrometers require the target to be a grey body and for it to have large temperatures, T>300°C, making this method unsuitable for measuring the surface temperature of the Yankee cylinder. Gold cup pyrometers require the gold hemisphere to have a reflectance of ρ=1. Because of the environment surrounding the Yankee cylinder it would be difficult keeping the gold hemisphere as clean as required making this method unsuitable as well.

Denna studie syftar till att undersöka kvinnors representation i läroböcker i fysik på gymnasiet samt på vilket sätt representationen av kvinnor och män skiljer sig åt i böckerna. Tre populära läroboksserier har undersökts för kurserna Fysik 1 och Fysik 2. Resultatet har sedan jämförts med hur det har sett ut i liknande böcker under 80- och 90-talet. Resultatet visar att kvinnan är närvarande och aktiv i alla undersökta böckerna men i de flesta fall inte i samma grad som mannen. Den kvinnliga fysikern erkänns inte alltid som fullvärdig forskare och en könsstereotypisk syn på kvinnan kan lyftas fram. Samtidigt finns det även fall där kvinnan blir en hyllad fysiker och kvinnan visas som en stark, handlingskraftig och intelligent person. I dagens fysikböcker får kvinnan ett större utrymme än hon tidigare har haft men representationen av kvinnor och män skiljer sig fortfarande åt. I flera fall är det mannen som är norm i böckerna och flera stora kvinnliga fysiker glöms bort.

<p>An all-pervading feature of the work presented in this thesis is the study of ultrafast dynamics, both theoretically and experimentally, in terms of time-dependent wave functions (wave packets).</p><p>We have experimentally, by pump-probe fluorescence spectroscopy, examined spin-orbit interactions, by time-tracing molecular wave packets on excited states of diatomic rubidium, and the main channels causing the fast predissociation from one of those states is revealed.</p><p>The time evolution of wave packets and their extension in space, in addition to varying transition dipole moment is of specific interest in the semiclassically derived expressions for the total ion signal, in the context of pump-probe ionization spectroscopy on diatomic molecules.</p><p>We have experimentally, by pump-probe fluorescence spectroscopy, addressed a previously derived theoretical prediction about level interactions between atomic levels with all angular momentum quantum numbers equal but different principal quantum numbers. Hence, the ultrafast progression of atomic radial wave packets are disclosed in terms of quantum beat frequencies and explained theoretically in the context of pump-probe fluorescence spectroscopy.</p><p>Preliminary fluorescence up-conversion experiments are as well treated in this thesis with the aim to reveal further experimental knowledge on the previously derived theoretical prediction on the specific level interactions mentioned above.</p>

This thesis concerns the analytical and numerical analysis of the water vapour condensation from the multicomponent mixture of condensable and noncondensable gases in the area of the nuclear reactor thermal-hydraulic safety. Following an extensive literature review in this field three aspects of the condensation phenomenon have been taken into consideration: a surface condensation, a liquid condensate interaction with gaseous mixtures and a spontaneous condensation in supersaturated mixtures. In all these cases condensation heat and mass transfer rates are significantly dependent on the local mixture intensive parameters like for example the noncondensable species concentration. In order to analyze the multicomponent mixture distribution in the above-mentioned conditions, appropriate simplified physical and mathematical models have been formulated. Two mixture compositions have been taken into account: a binary mixture of water vapour with heavy noncondensable gas and a ternary mixture with two noncondensable gases with different molecular weights. For the binary mixture a special attention has been focused on the heavy gas accumulation in the near-interface region and the influence of liquid film instabilities on the interface heat and mass transfer phenomena. For the ternary mixture of gases a special attention has been paid to the influence of the light gas and induced buoyancy forces on the condensation heat and mass transfer processes. Both analytical and numerical methods have been used in order to find solutions to these problems. The analytical part has been performed applying the boundary layer approximation and the similarity method to the system of film and mixture conservation equations. The numerical analysis has been performed with the in-house developed code and commercial CFD software. Performing analytical and CFD calculations it has been found that most important processes which govern the multicomponent gas distribution and condensation heat transfer degradation are directly related to the interaction between interface mass balances and buoyancy forces. It has been observed that if the influence of the liquid film instabilities is taken into consideration the heat transfer enhancement due to the presence of different types of waves is directly related to the internal film hydrodynamics and shows up in the mixture-side heat transfer coefficient. The model developed for the dispersed phase growth shows that degradation of the condensation heat transfer rate, which is a consequence of degradation of the convective mass flux, should be taken into account for highly supersaturated gaseous mixtures and can be captured by combination with the mechanistic CFD surface condensation model. Keywords: condensation, noncondensable gases, CFD simulation, boundary-layer approximation, binary and ternary mixtures / <p>QC 20100623</p>

A non-destructive tomographic measurement technique for application on nuclear fuel assemblies has beendeveloped at the Uppsala University. Using this technique, the rod-by-rod distribution of selectedradioactive isotopes is determined experimentally. In the present work, the numerical technique to reconstruct the activity distribution inside the fuelassemblies has been analyzed. Three iterative reconstruction algorithms have been investigated, ART(Additive Reconstruction Technique), ML (Maximum Likelihood) and ASIRT (Additive SimultaneousIterative Reconstruction Technique). It was found that the ART algorithm is too sensitive to data points where the gamma-ray intensityis low, while ASIRT handles it in the best manner. Furthermore, ASIRT appears to be the most stablealgorithm and produces the best agreement to theoretical data.

This licentiate thesis describes a novel nondestructive measuring technique for determiningspatial distributions of two-phase water flows. In Boiling Water Reactors, which compose themajority of the world's commercial nuclear reactors, this so called void distribution is of importance for safe operation. The presented measurement technique relies on fast neutron transmission tomography using portable neutron generators. Varying hardware options for such an instrument based on this technique and a prototype instrument, which is under construction, are described. The main design parameters are detailed and motivated from a performance point of view. A Paretomultiple objective optimization of the count rate and image unsharpness is presented. The resulting instrument design comprises an array of plastic scintillators for neutron detection. Such detector elements allow for spectroscopic data acquisition and subsequent reduction of background events at low energy by means of introducing an energy threshold in the analysis. The thesis includes two papers: In paper I, the recoil proton energy deposition distribution resulting from the interaction of the incoming neutrons is investigated for thin plastic scintillator elements. It is shown that the recoil proton losses have a large effect on the pulse height distribution and the intrinsic neutron detection efficiency is calculated for varying energy thresholds. In paper II the performance of the planned FANTOM device is investigated using the particle transport code MCNP5. An axially symmetric phantom void distribution is modeled and there construction is compared with the correct solution. According to the solutions, the phantom model can be reconstructed with 10 equal size ring-shaped picture elements, with a precision of better than 5 void percent units using a deuterium-tritium neutron generator with a yield of 3 · 107 neutrons per second and a measurement time of 13 h. However, it should be noted that commercial neutron generators with a factor of 103 higher yields exist and that the measurement time could decrease to less than a minute if such a neutron generator would beutilized. / STUNT

Quantum computers, like classical ones, need to be capable of sending informa-tion between different parts of the computer. Spin chains are one viable method of sending qubits while preserving the superposition and entanglement of a state. We use quantum speed limits, which give bounds on how fast non-relativistic quantum systems can evolve, to study simple Heisenberg chains and their efficacy as quantum channels.