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We extend earlier work on leading logarithms in the massive nonlinear O(n) sigma model to the case of SU(N) x SU(N)/SU(N) which coincides with mesonic Chiral Perturbation Theory for N flavours of light quarks. We discuss the leading logarithms for the mass and decay constant to six loops and for the vacuum expectation value ((q) over barq) to seven loops. For dynamical quantities the expressions g
We calculate the radiation spectrum off a q (q) over bar pair of a fixed opening angle theta(q (q) over bar) traversing a medium of length L. Multiple interactions with the medium are handled in the harmonic oscillator approximation, valid for soft gluon emissions. We discuss the time-scales relevant to the decoherence of correlated partons traversing the medium and demonstrate how this relates to
The modeling of color reconnection has become one of the dominant sources of systematic uncertainty in the top mass determination at hadron colliders. The uncertainty on the top mass due to color reconnection is conventionally estimated by taking the difference in the predictions of a model with and a model without color reconnection. We show that this procedure underestimates the uncertainty when
The opacity of the Earth to incident ultrahigh energy neutrinos is directly connected with the behavior of the neutrino-nucleon (sigma(nu N)) cross sections in a kinematic range utterly unexplored. In this work we investigate how the uncertainties in sigma(nu N) due the different QCD dynamic models modify the neutrino absorption while they travel across the Earth. In particular, we compare the pre
This dissertation is about the view of writing. One of the intentions of the study is to analyse different notions of writing that become manifest in media debates about student writing. Another intention is to analyse conceptions of writing in curricula and course plans for upper secondary school in Sweden from 1970 to 2011. Drawing from theories of critical discourse analysis, the study aims atThis dissertation is about the view of writing. One of the intentions of the study is to analyse different notions of writing that become manifest in media debates about student writing. Another intention is to analyse conceptions of writing in curricula and course plans for upper secondary school in Sweden from 1970 to 2011. Drawing from theories of critical discourse analysis, the study aims at
We use the results from a recent investigation of hard parton-parton gravitational scattering in the ADD scenario to make semi-quantitative predictions for a few standard high-E-perpendicular to jet observables at the LHC. By implementing these gravitational scattering results in the PYTHIA event generator and combining it with the CHARYBDIS generator for black holes, we investigate the effects of
The Pythia program can be used to generate high-energy-physics 'events', i.e. sets of outgoing particles produced in the interactions between two incoming particles. The objective is to provide as accurate as possible a representation of event properties in a wide range of reactions, within and beyond the Standard Model, with emphasis on those where strong interactions play a role, directly or ind
We present the generating function approach to the perturbative exponentiation of correlators of a product of Wilson lines and loops. The exponentiated expression is presented in closed form as an algebraic function of correlators of known operators, which can be seen as a generating function for web diagrams. The expression is naturally split onto two parts: the exponentiation kernel, which accum
Jenny Hansson NGEA51 13/1 2017 Internship at Naturum Kullaberg - With a Focus on Sustainable Fishery in Höganäs Municipality I had my internship at naturum Kullaberg, which is situated in the Kullaberg Nature Reserve in northwestern Skåne. Both the naturum and the nature reserve are run by the County Administrative Board of Skåne (Länsstyrelsen Skåne). My main focus was to collect data on the loca
https://www.nateko.lu.se/sites/nateko.lu.se/files/internship_at_naturum_kullaberg_summary.pdf - 2026-05-28
This document describes the package CHIRON which includes two libraries, chironitself and jbnumlib. chiron is a set of routines useful for two-loop numerical results in chiral perturbation theory (ChPT). It includes programs for the needed one-and two-loop integrals as well as routines to deal with the ChPT parameters. The present version includes everything needed for the masses, decay constants
This biennial Review summarizes much of particle physics. Using data from previous editions., plus 2778 new measurements from 645 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and s
We extend our earlier work on the massive O(N) non-linear sigma model to other observables. We derive expressions at leading order in the large N expansion at all orders in the loop expansion for the decay constant, vacuum expectation value, meson meson scattering and the scalar and vector form factors. This is done using cactus diagram resummation using a generalized gap equation and other recurs
Naturreservat – områden som behöver vård och omsorg Ett naturreservat är ett skyddat naturområde som många gånger bjuder på varierande och vacker natur. Kanske har du någon gång besökt ett reservat och strövat i lövskogen, tittat på fåglar eller kanske fikat på ängsmarken. Vad du troligtvis inte tänkte på då är hur mycket vård och omsorg som faktiskt kan ligga bakom ett välskött naturreservat. Fö
We propose a new description of the jet quenching phenomenon observed in nuclear collisions at high energies in which coherent parton branching plays a central role. This picture is based on the appearance of a dynamically generated scale, the jet resolution scale, which controls the transverse resolution power of the medium to simultaneously propagating color probes. Since from the point of view
We use three-flavour hard pion Chiral Perturbation Theory (HPChPT) in both the heavy meson and a relativistic formulation to calculate the chiral logarithms m(2) log (m(2)/mu(2)) contributing to the formfactors of the B-(s) -> pi, K, eta and D-(s) -> pi, K, eta transitions at momentum transfer q(2) away from the endpoint q(max)(2) = (m(B) - m(M))(2). We compare our results with CLEO D -> pi and D
A unification of left-right SU(3)L×SU(3)R, color SU(3)C, and family SU(3)F symmetries in a maximal rank-8 subgroup of E8 is proposed as a landmark for future explorations beyond the Standard Model (SM). We discuss the implications of this scheme in a supersymmetric (SUSY) model based on the trinification gauge [SU(3)]3 and global SU(3)F-family symmetries. Among the key properties of this model are
In this review, we present an up-to-date phenomenological summary of research developments in the physics of the Quark-Gluon Plasma (QGP). A short historical perspective and theoretical motivation for this rapidly developing field of contemporary particle physics is provided. In addition, we introduce and discuss the role of the quantum chromodynamics (QCD) ground state, non-perturbative and latti
In this short review, I discuss basic qualitative characteristics of quantum non-Abelian gauge dynamics in the non-stationary background of the expanding Universe in the framework of the standard Einstein-Yang-Mills formulation. A brief outlook of existing studies of cosmological Yang-Mills fields and their properties will be given. Quantum effects have a profound impact on the gauge field-driven
We compute the O(αsα2) and O(αs2α) contributions to the production cross section of a Z boson with one b jet at the Large Hadron Collider (LHC) and study their phenomenological relevance for LHC physics. The accurate prediction of hadronic Z+b-jet production is needed to control a background that greatly affects both the measurement of Higgs-boson properties and the searches of new physics at the
We study fully differential quarkonia photoproduction observables in ultraperipheral collisions as functions of momentum transfer squared. We employ the dipole picture of the QCD part of the scattering with proton and nucleus targets, with the projectile being a quasireal photon flux emitted by an incoming hadron. We analyze such observables for ground J/ψ, (1S) and excited ψ′, (2S) states whose l
