Filetype
Abstract in Undeterminednew fit is done to obtain numerical values for the order p(4) low-energy-constants L(i)(r) in Chiral Perturbation Theory. This includes both new data and new calculated observables. We take into account masses, decay constants, K(l4), pi pi and pi K scattering lengths and slopes and the slope of the pion scalar formfactor. We compare in detail where the changes w.r.t. the 1
Multidimensional integrals are used in many areas of physics; electrodynamics, quantum mechanics and statistical physics, to name a few. Many integrals can not be solved analytically, but can instead be approximated numerically. VEGAS is a Monte Carlo integration algorithm, which specializes it in approximating multidimensional integrals. By treating each integration variable independently, VEGAS
In this work we investigate the hard and soft interactions in the multiple parton interactions (MPI) simulation in Herwig7. The investigation covers how the number of soft and hard interactions in an event is linked to the multiplicity of final state particles. We also present a labeling system for particles produced by different interactions, which we then use to classify the final state particle
Medium-induced gluon radiation gives rise to the strong energy loss observed in single hadron spectra in heavy ion collisions. Its angular structure, leading e.g. to intra-jet correlations, is only known for the one-gluon inclusive case. In the vacuum, properties such as angular ordering appear when considering less inclusive distributions due to destructive interference effects. We present a calc
In this work, we present a thorough analysis of scalar P -wave χQ0, Q = c, b quarkonia electromagnetic form factors for the γ∗γ∗→ χQ0 couplings, as well as their hadroproduction observables in k⊥-factorisation using the light-front (LF) potential approach for the quarkonium wave function. The electromagnetic form factors are presented as functions of photon virtualities. We discuss the role of the
The hadronic light-by-light contribution to the muon anomalous magnetic moment depends on an integration over three off-shell momenta squared (Qi2) of the correlator of four electromagnetic currents and the fourth leg at zero momentum. We derive the short-distance expansion of this correlator in the limit where all three Qi2 are large and in the Euclidean domain in QCD. This is done via a systemat
We study the propagation and diffusion of electric charge fluctuations in the Bjorken hydrodynamic model with both white and Catteneo noise using purely numerical methods. We show that a lattice of noise fluctuations is required to fully calculate the two-point correlators of charge. We introduce a numerical procedure to solve the stochastic differential equations that arise from the charge conser
Phenomenological models of multiparticle production have become increasingly important for the interpretation of experimental data in high energy physics. The evolution of these models fills a gap left open by the present limited theoretical understanding of the hadronization process, i.e. the transformation of outgoing colored partons into color singlet hadrons. The three main schools of thought,
A phenomenological study of the isolated photon production in high energy pp and pA collisions at RHIC and LHC energies is performed. Using the color dipole approach we investigate the production cross section differential in the transverse momentum of the photon considering three different phenomenological models for the universal dipole cross section. We also present the predictions for the rapi
We discuss γ ∗γ ∗→ ηc(1S) ; ηc (2S) transition form factor for both virtual photons. The general formula is given. We use difierent models for the cc̄ wave function obtained from the solution of the Schrödinger equation for diffierent cc̄ potentials: harmonic oscillator, Cornell, logarithmic, power-law, Coulomb and Buchmüller{Tye. We showed some examples of wave functions in the Light Front repres
Studies of fully-reconstructed jets in heavy-ion collisions aim at extracting thermodynamical and transport properties of hot and dense QCD matter. Recently, a plethora of new jet substructure observables have been theoretically and experimentally developed that provide novel precise insights on the modifications of the parton radiation pattern induced by a QCD medium. This report, summarizing the
Aims. We have measured and calculated lifetimes of high lying levels in Nb II, and derived absolute transition probabilities by combining the lifetimes with experimental branching fractions. Methods. The lifetimes were measured using time-resolved laser-induced fluorescence in a two-photon and two-step excitation scheme. The branching fractions were measured in intensity calibrated spectra from a
Monte Carlo Event Generators are important tools for the understanding of physics at particle colliders like the LHC. In order to best predict a wide variety of observables, the optimization of parameters in the Event Generators based on precision data is crucial. However, the simultaneous optimization of many parameters is computationally challenging. We present an algorithm that allows to tune M
We construct a model based on the electroweak gauge group SU(2)L×SU(2)R×U(1)B-L augmented by an S3 symmetry. We assign nontrivial S3 transformation properties to the quarks, and consequently we need two scalar bidoublets. Despite the extra bidoublet, we have only six Yukawa couplings thanks to the discrete symmetry. Diagonalization of the quark mass matrices shows that at the leading order only th
Parton showers have become a standard component in the description of high-energy collisions. Nowadays most final-state ones are of the dipole character, wherein a pair of partons branches into three, with energy and momentum preserved inside this subsystem. For initial-state showers a dipole picture is also possible and commonly used, but the older global-recoil strategy remains a valid alternati
We extend the definition of the star product introduced by Lunin and Maldacena to study marginal deformations of N=4 SYM. The essential difference from the latter is that instead of considering U(1)xU(1) non-R-symmetry, with charges in a corresponding diagonal matrix, we consider two Z_3-symmetries followed by an SU(3) transformation, with resulting off-diagonal elements. From this procedure we ob
We report on our studies of the neutron-skin effects in high-pT observables at the LHC. We study the impact of the neutron-skin effect on the centrality dependence of inclusive direct photon, highpT hadron and W± production in nuclear collisions at the LHC. The neutron-skin effect refers to the observation that in spherical heavy nuclei, the tail of the neutron distribution extends farther than th
We present and study a minimal structure-based model for the self-assembly of peptides into ordered β-sheet-rich fibrils. The peptides are represented by unit-length sticks on a cubic lattice and interact by hydrogen bonding and hydrophobicity forces. Using Monte Carlo simulations with >10^{5} peptides, we show that fibril formation occurs with sigmoidal kinetics in the model. To determine the mec
