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Jet quenching in heavy ion collisions and in particular the sub-structure of quenched jets are promising tools for investigating the microscopic processes underlying jet quenching and the background medium's response to energy and momentum depositions. A quantitative understanding of the data can, however, be complicated by the presence of initial state radiation in reconstructed jets. Using an ex
The extraction of the W-boson mass, a fundamental parameter of the Standard Model, from hadron-hadron collision requires precise theory predictions. In this regard, angular coefficients are crucial to model the dynamics of W-boson production. In this work, we provide, for the first time, angular coefficients at NNLO QCD + NLO EW accuracy for finite transverse momentum W-boson at the LHC. The corre
New experimental lifetimes for two levels in doubly ionized tungsten, W III, have been obtained using the time-resolved laser-induced-fluorescence technique. Theoretical oscillator strengths obtained from a HFR calculation including the effects of core-polarization are reported for all transitions from levels below E < 70000 cm(-1) and with log g f >= -2, thus greatly extending our knowledge of th
Using a decapitation ischemia model, we studied translocation of proteins to and from the cytosol in normothermic (NT) and hypothermic (HT) rat brains. 2D gel analysis identified 74 proteins whose cytosolic level changed significantly after 15 min of ischemia. HT preserved the cytosolic levels of several glycolytic enzymes, as well as many plasticity related proteins, otherwise decreased following
We consider the diffractive Drell-Yan process in proton-(anti) proton collisions at high energies in the color dipole approach. The calculations are performed at forward rapidities of the leptonic pair. The effect of eikonalization of the universal "bare" dipole-target elastic amplitude in the saturation regime takes into account the principal part of the gap survival probability. We present predi
We study the radiation of a highly energetic partonic antenna in a colored state traversing a dense QCD medium. Resumming multiple scatterings of all involved constituents with the medium we derive the general gluon spectrum which encompasses both longitudinal color coherence between scattering centers in the medium, responsible for the well known Landau-Pomeranchuk-Migdal (LPM) effect, and transv
We apply the resummed version of the Luscher formula to analyze finite volume corrections to the mass of the nucleon and of heavy mesons. We show that by applying the subthreshold expansion of the scattering amplitudes one can express the finite volume corrections in terms of only a few physical observables and the size of the box. In the case of the nucleon, the available information about the qu
In this paper we derive an integral equation for the evolution of unintegrated (longitudinally) polarized quark and gluon parton distributions. The conventional Catani-Ciafaloni-Fiorani-Marchesini (CCFM) framework is modified at small x in order to incorporate the QCD expectations concerning the double ln(2)(1/x) resummation at low x for the integrated distributions. Complete Altarelli-Parisi spli
We develop a general recipe for constructing orthogonal bases for the calculation of color structures appearing in QCD for any number of partons and arbitrary N-c. The bases are constructed using hermitian gluon projectors onto irreducible subspaces invariant under SU(N-c). Thus, each basis vector is associated with an irreducible representation of SU(N-c). The resulting multiplet bases are not on
Using Chiral Perturbation Theory at one-loop we analyze the consequences of twisted boundary conditions. We point out that due to the broken Lorentz and reflection symmetry a number of unexpected terms show up in the expressions. We explicitly discuss the pseudo-scalar octet masses, axial-vector and pseudo-scalar decay constants and electromagnetic form-factors. We show how the Ward identities are
General-purpose Monte Carlo event generators have become important tools in particle physics, allowing the simulation of exclusive hadronic final states. In this article we examine the PYTHIA 8 generator, in particular focusing on its parton-shower algorithms. Some relevant new additions to the code are introduced, that should allow for a better description of data. We also implement and compare w
Different aspects of the strong interaction in particle collisions are studied. Most of the work is based on the Lund string fragmentation model for hadron production. A model which incorporates interference between identical bosons in the string model is presented. With this model the consequences for the Bose-Einstein effect are investigated in detail. What happens at the end of the QCD cascades
The process K-l3 is calculated to two-loop order (p(6)) in chiral perturbation theory (ChPT) in the isospin conserved case. We present expressions suitable for use with previous work in two-loop ChPT where the order p(4) parameters (L-i(r)) were determined from experiment. We point out that all the order p(6) parameters (C-i(r)) that appear in the value of f(+)(0) relevant for the determination of
Radiative lifetimes of eight odd-parity states of Pt II, in the energy range from 51 408 to 64 388 cm−1, have been measured by means of the time-resolved laser-induced-fluorescence technique. Free, singly ionized platinum ions were obtained in a laser-produced plasma and a tunable laser with 1.5 ns duration pulse was used to selectively excite the Pt+ ions. The comparison of the experimental resul
In this thesis, the mass singularities occurring in the cross-section of electron scattering processes are investigated. Two types of scatterings are studied: Quantum Electrodynamics (QED) scatterings, and Perturbative Quantum Gravity (PQG) scatterings. We show how mass singularities in QED and PQG cancel when real and virtual diagrams are included in the scattering cross-section. We find that in
This thesis investigates a possible extension to the Standard Model: the Chirally Symmetric Technicolor Model. The motivation is to explain the origin of the electroweak interaction scale by introducing a new interaction. The thesis is based on the two-flavour Technicolor model presented in ”Chiral-Symmetric Technicolor with Standard Model Higgs boson” by Pasechnik et. al. [1], and extends it to t
This thesis aims to describe the little group scaling and how it simplifies the calculation of scattering amplitudes. The little group has the defining property that it leaves a particular four-momentum invariant, which is used to describe how the internal structure of a particle is transformed under the little group. An important part in the study of little group scaling is the spinor-helicity fo
Syftet med arbetet har varit att, med hjälp av bayesiansk sannolikhetsteori som bevisvärderingsmetod, kritiskt analysera svenska människohandelsmål. Detta har gjorts för att utröna om det förekommer tecken på bristande bevisvärdering från domstolarna som bidrar till att rekvisit ej anses styrkta i dessa mål där någon blir friad, och i utsträckning bidragit till bevisproblematik kring brottet. Syft
Gravitational scattering in the ADD-model is considered at both sub- and transplanckian energies using a common formalism. By keeping a physical cut-off in the KK tower associated with virtual KK exchange, such as the cut-off implied from a finite brane width, troublesome divergences are removed from the calculations in both energy ranges. The scattering behavior depends on three different energy
