Sökning: "Mattias Sjö"

Hittade 4 avhandlingar innehållade orden Mattias Sjö.

  1. 1. Multi-Meson Dynamics in Chiral Perturbation Theory

    Författare :Mattias Sjö; Partikel- och kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spridningsamplituder; Effektiv Fältteori; Spontant symmetribrott; Ickelinjära sigmamodellen; Kirala Lagrangianer; Hadronspektroskopi; Strukturer och Interaktioner; Gitter-QCD; Scattering amplitudes; Effective Field Theories; Spontaneous Symmetry Breaking; Nonlinear sigma model; Chiral Lagrangians; Hadronic Spectroscopy; Structure and Interactions; Lattice QCD;

    Sammanfattning : This thesis concerns scattering of light mesons in the case where the number of external particles exceeds four (that is, three or more particles in the initial or final state), calculated using chiral perturbation theory.This is both of theoretical interest in the study of scattering amplitudes, and relevant for systems of three or more pions simulated using lattice quantum chromodynamics. LÄS MER

  3. 2. Jet Production and Parton Dynamics in Deep Inelastic Scattering

    Författare :Mattias Davidsson; Partikel- och kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum field theory; Elementary particle physics; DIS; ep scattering; HERA; H1; jets; small-x; Parton Dynamics; Elementarpartikelfysik; kvantfältteori; Fysicumarkivet A:2001:Davidsson;

    Sammanfattning : Hard QCD processes have been studied by measuring the di-jet event rate for deep inelastic scattering in the kinematic range 5 < Q2 < 100 GeV2 and 10-4 < x < 10-2. The jets we re reconstructed using the cone algorithm in the hadronic center-of-mass frame in which the transverse momentum of the jets were required to be greater than 5 GeV. LÄS MER

  4. 3. Plankton communities in a changing world - responses to temperature, brownification and lake restoration

    Författare :Mattias Ekvall; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Climate change; temperature; warming; brownification; biomanipulation; zooplankton; cyanobacteria; microcystin; grazing; Daphnia;

    Sammanfattning : The effects of increasing temperatures, in light of climate change, have been a well-studied topic during the past decades. However, aquatic ecosystems are also faced with additional challenges such as increasing water colour, known as “brownification”. LÄS MER

  5. 4. Glaciodynamics, Deglacial Landforms and Isostatic Uplift during the last Deglaciation of Norrbotten, Sweden

    Författare :Mattias Lindén; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sedimentologi; Sedimentology; Geologi; physical geography; Geology; glaciotectonic; thrust stacking; deforming bed; ribbed moraine; Niemisel moraine; De Geer moraine; isostatic uplift; glaciodynamics; deglaciation; klimatologi; kartografi; marklära; Fysisk geografi; geomorfologi; geomorphology; cartography; climatology; pedology;

    Sammanfattning : The aim of this thesis was to reconstruct the glaciodynamics, deglacial landforms, isostatic uplift and to date the deglaciation. Glaciodynamics and deglacial landforms were focused on to provide a process and depositional model for De Geer moraine and Niemisel moraine and to reveal their internal and spatial relationship, based on detailed sedimentological and structural investigations. LÄS MER