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In this project commercial BSF Si solar cells have been processed in order to develop a suitable interconnect for a possible tandem solar cell. The Ag original top contacts have been removed and replaced with TiSi2 formed using the SALICIDE process at 3 different temperatures: 500 °C, 650 °C and 750 °C. Raman spectroscopy and EDS maps have been used to prove the successful formation of the TiSi2 contacts for the 750 °C temperature. As part of this work we also developed a MATLAB script which successfully fits the measured IV curve of a Si solar cell and extrapolates the values of the components of the equivalent circuit. The script also identifies and quantifies the energy losses percentage for different loss mechanisms. The script was used to characterize commercial BSF Si solar cells and to simulate their behavior in a tandem configuration by IV measurements under filtered light. The results of this characterization was used to predict the requirements of a possible top solar cell for a tandem configuration.

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By the use of highly intense X-ray pulses, with durations in the scale of tenths of fs, high resolutiondiffraction images of the structures of individual macro-molecules can be obtained. To generatea self-consistent 3D-image of the structures the diffraction images of thousands of copies of thesame molecules have to be compounded. The composition relies on advanced algorithms with longcomputational times and is not always successful or even possible. Simulations of proteins in electricfields have proven that pre-orientation of molecules could yield results otherwise unobtainable.When a molecule enters the electric field it will experience an increasing field strength, i.e. a timedependent electric field, and the change in the field strength will be a function of the moleculestranslational velocity. Proteins are compounded by amino-acids. If amino-acids structures arealtered it could indicate that the structures of proteins would be altered as well. The initial objectof this project was to determine if there exists any critical molecular velocities at which the structuresof amino-acids significantly are altered. If the structures are altered the diffraction imageswill be of other structures than of those intended. The project was based on computer simulations.When approximating the plates of a capacitor as two point charges it was found that the timelapsewould be too long for the simulations intended. Instead it was asked at which field strengthsthe amino-acids would start to lose their essential structures. The amino-acids were simulated inconstant electric fields on a computer at Uppsala University. It was found that the amino-acidscould start to lose their structures in fields intended for pre-orientation of proteins. It was alsofound that the field strengths required for a change in the intramolecular forces depended on thesize of the amino-acid as well as the direction of the field in relation to the amino-acids orientation.

We review modern methods of scattering amplitude computations, beginning with color-decomposition that decomposes the amplitude into a color-dependentand a color-independent part of partial color-ordered amplitudes. We then show how a full amplitude can be described through the color-factor, propagator structure, and kinematic numerator of cubic color-ordered diagrams. The color-factors obey a Lie algebra and as such satisfy the Jacobi identity. We are able to impose the color-kinematics duality that states that the kinematic numerators also obey this identity. Because of this it is possible to write down sets of Jacobi equations for the numerator through their diagrammatic expression. These can be solved for a set of master numerators through which all other numerators can be expressed linearly. We find such solutions for the tree-level, one-loop, and two-loop diagrams for any numberof particles.

The purpose with this thesis is to see which subject-specific concepts occur in middle school physics textbooks in the solar system. The second goal of the work is to analyze how these subject-specific concepts are explained to give an understanding of the concepts. This empirical work attempts to answer two questions:• What subject-specific concepts are found about the solar system in middle school physics textbooks?• How are the subject-specific concepts of the solar system explained so that they provide an understanding of the concepts?To answer these questions, a quantitative content analysis and a qualitative text analysis were made. The methods were applied to three different Swedish middle school textbooks. The theoretical framework used in this work is subject-specific concepts, analogies, metaphors and conceptual development. Subject-specific concepts are used to define the subject-specific concepts. Analogies and metaphors are used as a pair of glasses to show how students can acquire new concepts. The theory of conceptual development was used to gain perspective on how students understand new concepts. What I found out was that the subject-specific concepts used to explain our solar system were sun, moon, planet, earth, asteroid, earth axis, solar system, celestial bodies, gravity, attraction, dwarf planets, comets and crater. The result showed that none of the textbooks used analogies. A few metaphors were used but the explanations that appeared as the most except for no use were examples and relationships. In two textbooks some subject-specific concepts had been introduced earlier several times.Keywords: Physics, textbook, explained, solar system.Nyckelord: Fysik, lärobok, förklaringar, solsystemet.

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I replicated the H/A → τ μ τ had analysis of the MSSM extension to the stan-dard model with the ATLAS experiment. I investigated, using a transformedBDT score for τ -lepton identification with a flat distribution, with more work-ing points than the standard loose, medium and tight, the sensitivity of theanalysis. I then compared for each of the working points and found new signalefficiencies that are more sensitive for this analysis than the standard workingpoints. / I replicated the H/A → τ μ τ had analysis of the MSSM extension to the stan-dard model with the ATLAS experiment. I investigated, using a transformedBDT score for τ -lepton identification with a flat distribution, with more work-ing points than the standard loose, medium and tight, the sensitivity of theanalysis. I then compared for each of the working points and found new signalefficiencies that are more sensitive for this analysis than the standard workingpoints.

The pairing correlation has long been recognized as the dominant many-body correlation beyond the nuclear mean field. Pairing plays an essential role in many nuclear phenomena including the occurrence of a systematic odd-even staggering (OES) of the nuclear binding energy. Pairing interaction plays, in particular, a significant role in the stability of weakly bound nuclei. Therefore it has been one of the most critical topics in nuclear physics because of the weakly bound structure of all newly discovered nuclei. Beyond the line of stability, pairing interaction is not a residual interaction anymore. Its strength can be of the same order of magnitude as the mean field.  In this thesis we have focused on the pairing interaction in atomic nuclei under extreme conditions to investigate the structure of loosely bound nuclei near the dripline; to probe and globally assess different outcomes of various zero-range pairing interactions and their effect on the loosely bound low angular momentum states. How much can density-dependence in zero-range pairing interaction nuclei affect the line of stability? Calculations predict that pure density-dependent pairing interaction so-called surface interaction enhances the collectivity and gives stronger neutron pairing gap in nuclei far from stability, while, the density dependence pairing interaction does not affect the gap for bound nuclei as much. The odd-even staggering of nuclear binding energies has been investigated to estimate the empirical pairing gap. A 3-point formula Δ(3)C (1/2[B(N,Z)+B(N −2,Z)−2B(N −1,Z)]) is advocated in this thesis, which we believe it is more suitable to measure the magnitude of pairing gap in even-even nuclei. The strength of Δ(3)C can be a good indicator of the two-particle spatial correlation. One-quasiparticle energies and binding energy for those odd nuclei, which can be approximated by spherical symmetry, are calculated to obtain binding energy odd-even staggering (OES) in all known semi-magic even-even nuclei. The pairing strength is fitted globally to all available data on the OES of semi-magic nuclei with Z ≥ 8. The difference between different zero-range density-dependent pairing interactions reduces with this global fitted parameter. The difference between the mean pairing gap and the OES gets larger as we get closer to the dripline. At the end of the thesis, a simple model has been developed which shows that when the mean-field becomes shallower the odd-even staggering of charge radii is reduced.This thesis covers results that are not included in the three published papers and some complementary works on the subject. / Parkopplingen i atomkärnan anses vara den dominerande mångkropparskorrelationen efter kärnmedelfältet. Parkoppling i atomkärnan spelar en viktig roll i många kärnfenomen,inklusive förekomsten av en systematisk udda-jämn förskjutning (OES) av bindningsenergin.Hos svagt bundna atomkärnor däremot spelar parkopplingen en signifikant roll för stabiliteten. Det gäller alla de nyupptäckta neutronrika atomkärnor som karakteriseras aven svag bindningsenergi där således parkopplingen blir ett kritiskt fenomen. När vi lämnar stabilitetslinjen och närmar oss linjen av spontan neutronsönderfall är parkopplingeninte längre obetydlig, utan tvärtom spelar en viktig roll för stabiliteten hos atomkärnan.Dess styrka kan vara av samma storleksordning som medelfältet. I denna avhandling har vi fokuserat på parkopplingen i atomkärnor under extrema villkor i syfte att undersöka strukturen hos löst bundna atomkärnor nära linjen för neutronsönderfall; att utforska och globalt bedöma resultaten av olika parkopplingar baserad på en deltakraft (räckvidd noll) och deras effekt på löst bundna tillstånd med lågt rörelsemängdsmoment. Hur mycket kan ett täthetsberoende i parkopplingen påverka stabilitetslinjen? Beräkningarna förutsäger att ren densitetsberoende växelverkan för parkoppling, så kallad ytväxelverkan, ökar kollektiviteten i atomkärnan och ger ett större pargap för neutroner i kärnor långt ifrån stabilitetslinjen,medan densitetsberoende parkoppling påverkar inte gapet för bundna kärnor i samma omfattning.Udda-jämn-spridning av bindningsenergier har undersökts för att hitta storleken på parkopplingens gap. En 3-punktsformel Δ(3)C (1/2[B(N,Z)+B(N −2,Z)−2B(N −1,Z)]) förespråkas i denna avhandling, som vi anser vara mera lämplig för att mäta storleken på pargapet i jämn-jämna kärnor. Storleken på Δ(3)C kan vara en bra indikator på rumskorrelationen mellan två nukleoner. En-kvasipartikelenergi för de udda kärnorna, som kan approximeras med sfärisk symmetri, beräknas för att erhålla udda-jämn spridning (OES) med avseende på bindningsenergin för alla kända semi-magiska jämn-jämna kärnor. Parkopplingsstyrkan är globalt anpassat med all tillgänglig data på OES vad gäller semi-magiska kärnor med Z ≥ 8. Skillnaden mellan olika täthetsberoende parkopplingar med vår växelverkan minskar med dessa globalt anpassade parametrar. Skillnaden mellan det teoretiska genomsnittliga parkopplingsgapet och OES blir större när vi kommer närmare tröskeln för atomkärnans stabilitet. I slutet av avhandlingen har en schematisk modell utvecklats som, genom attgöra medelfältet grundare, reducerar de udda-jämnt spridda laddningsradierna. Avhandlingen innehåller dessutom resultat som inte ingår i de tre publicerade artiklarna samt några kompletterande arbeten om ämnet. / <p>QC 20171114</p>

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