Sökning: "Next-to-Leading order"

Visar resultat 1 - 5 av 11 uppsatser innehållade orden Next-to-Leading order.

1. 1. Studies of the axial-vector transition form factors of the process Ω− → W−Ξ0 in chiral perturbation theory

   Master-uppsats, Uppsala universitet/Kärnfysik

   Författare :Hélène De Munck; [2023]
   Nyckelord :Transition form Factors; Next-to-next-to-leading order; chiral perturbation theory; axial-vector; Ω− → W−Ξ0;

   Sammanfattning : This work is included in a broader research of the hadron theory group of Uppsala University and its collaborators tackling the quest for an understanding of the quark distribution inside hadrons by joining threedifferent approaches of QCD namely chiral perturbation theory, dispersion theory and lattice QCD. This thesis contributes by computing in chiral perturbation theory, the quark-masses dependence of form factors. LÄS MER

3. 2. On the vector transition form factors in the Ω- → Ξ0 W- decay

   Master-uppsats, Uppsala universitet/Kärnfysik

   Författare :Magnus Bertilsson; [2023]
   Nyckelord :QCD; Form factors; Vector form factors; Chiral perturbation theory; One-loop diagrams; Hadrons; Hadron physics; Hyperon decay; Hadron structure;

   Sammanfattning : To learn more about the structure of hadrons we study form factors. In the semi-leptonic decay Ω- → Ξ0W- two types of form factors arise namely the vector and axial-vector transition form factors. LÄS MER

4. 3. Rare Weak Decays of the Omega Baryon

   Master-uppsats, Uppsala universitet/Kärnfysik

   Författare :Cornelis Johannes Gerardus Mommers; [2022]
   Nyckelord :hadron; physics; nuclear; particle;

   Sammanfattning : We study rare decays of the Omega baryon using SU(3) chiral perturbation theory, a successfuleffective field theory of quantum chromodynamics at low energies. At leading-order, we calculatethe branching fractions of the decay Ω− → Ξππ for all possible combinations of pions. LÄS MER

5. 4. Fitting the pion and kaon mass and decay constant to lattice data

   Kandidat-uppsats, Lunds universitet/Teoretisk partikelfysik - Geonomgår omorganisation

   Författare :Hector Tiblom; [2021]
   Nyckelord :chiral perturbation theory; lattice QCD; pion mass; kaon mass; decay constant; low-energy QCD; Physics and Astronomy;

   Sammanfattning : We use lattice QCD data to perform a fit of the pion and kaon mass and decay constant to next-to-next-to-leading order (NNLO) in three-flavor Chiral Perturbation Theory (ChPT). To improve our fits, we make use of finite volume corrections at both one- and two-loop order. This turns out to provide a small but noticeable improvement of our fits. LÄS MER

7. 5. Simulation of Higgs boson pair production in Vector Boson Fusion at the LHC

   L3-uppsats, Uppsala universitet/Högenergifysik

   Författare :Daniela Romero; [2021]
   Nyckelord :Higgs boson; vbf; vector boson fusion; high energy physics; lhc; proton collision; madgraph; simulation;

   Sammanfattning : MadGraph5 is used to generate events with Higgs boson pairs from vector boson fusion (VBF) at leading-order (LO) and next-to-leading-order (NLO) accuracy in QCD. The simulations are used to compute fiducial cross-sections in proton-proton collisions at a centre-of-mass energy of 13 TeV, using several kinematic cuts on the outgoing jets, e.g. LÄS MER