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In the collinear factorization scheme the minijet cross section diverges for small k [perpendicular]. In the k[perpendicular]-factorization formalism this divergence is avoided, and it is possible to calculate the number of minijets and the E[perpendicular]-flow exclusively from HERA data, without reliance on a phenomenological soft cutoff. The hadron multiplicity is very sensitive to non-perturba
We review transverse momentum dependent (TMD) parton distribution functions, their application to topical issues in high-energy physics phenomenology, and their theoretical connections with QCD resummation, evolution and factorization theorems. We illustrate the use of TMDs via examples of multi-scale problems in hadronic collisions. These include transverse momentum q(T) spectra of Higgs and vect
We study the decays $K\to\pi\pi$ in one-loop two-flavour Chiral Perturbation Theory. We provide arguments why the calculation of the coefficient of the pionic chiral logarithm $\logm = M^2\log M^2$ is unique and then perform the calculation. As a check we perform the reduction of the known three-flavour result. Our result can be used to perform the extrapolation to the physical pion mass of direc
We add the Wess-Zumino-Witten term to the N = 3 massive nonlinear sigma model and study the leading logarithms in the anomalous sector. We obtain the leading logarithms to six loops for pi(0) -> gamma*gamma* and to five loops for y*pi pi pi. In addition we extend the earlier work on the mass and decay constant to six loops and the vector form factor to five loops. We present numerical results for
We study the deeply virtual Compton scattering off a spin-one particle, as the case for the coherent scattering off a deuteron target. We extend our approach, formulated initially for a spinless case, and discuss the role of twist three contributions for restoring the gauge invariance of the amplitude. Using twist three contributions and relations, which emanate from the QCD equations of motion, w
Comparative analysis of expressed sequence tags is becoming an important tool in molecular ecology for comparing gene expression in organisms grown in certain environments. Additionally, expressed sequence tag database information can be used for the construction of DNA microarrays and for the detection of single nucleotide polymorphisms. For such applications, we present PHOREST, a web-based tool
We present a method to include colour-suppressed effects in the Mueller dipole picture. The model consistently includes saturation effects both in the evolution of dipoles and in the interactions of dipoles with a target in a frame-independent way. When implemented in a Monte Carlo simulation together with our previous model of energy-momentum conservation and a simple dipole description of initia
Production of heavy photons (Drell-Yan), gauge bosons, Higgs bosons, and heavy flavors, which is treated within the QCD parton model as a result of hard parton-parton collision, can be considered a bremsstrahlung process in the target rest frame. In this review, we discuss the basic features of the diffractive channels of these processes in the framework of color dipole approach. The main observat
We report on experimental absolute oscillator strengths for 18 UV lines of Ru II, obtained by combining laser-induced fluorescence measurements of radiative lifetimes and branching fractions from line intensities in a calibrated Fourier-transform spectrum. HST/GHRS observations of the spectrum of the sharp-lined B star chi Lupi contain six of these lines, for which ''astrophysical'' relative f-val
It is argued that the assumption that the standard model particles live on a finite brane in the ADD model does in itself imply a finite propagator for virtual Kaluza-Klein mode exchange. The part of the propagator relevant for large distance scattering is cut-off-independent for scattering at distances large compared to the brane width. The matrix element corresponding to this part can also, at l
Att häva ett avtal är en ingripande åtgärd varför hävningspåföljden endast kan göras gällande vid väsentliga avtalsbrott enligt svensk rätt. Denna framställning syftar till att dels undersöka hur väsentlighetsrekvisitet är utformat enligt gällande rätt, dels utforska vilka rättsverkningar som uppkommer för den som mottagit en obefogad hävningsförklaring i den bemärkelsen att väsentlighetsrekvisiteThe purpose of this study is to clarify the concept of ”fundamental breach” as a necessary prerequisite for avoidance of contracts. Moreover, this study will explore the legal consequences arising from an unjustified declaration of avoidance and which strategic choices the recipient of such a declaration of avoidance is facing. The thesis is based on a traditional legal method and generally acce
Finite-volume corrections to the Lattice Quantum Chromo Dynamics (LQCD) calculation of the hadronic vacuum polarization are here considered to one loop, for the simplified case of one and two propagators of equal mass. Simplifications in the calculations are sought for by comparing computations in momentum space, time-momentum space and position space. The derivation of the finite-volume correctio
Partikelfysikens standardmodell är en av de mest exakta modellerna inom fysiken. Den beskriver interaktionerna mellan fundamentala partiklar som kvarkar och leptoner, hur Higgspartikeln ger massa till andra partiklar och tre av universums fyra fundamentala krafter: elektromagnetism, svag växelverkan och stark kärnkraft. Tyvärr finns det frågor som inte ens standardmodellen kan svara på. "Varf
The Next to Minimal Supersymmetric Standard Model (NMSSM) allows a CP violating phase at tree level in the Higgs sector. This CP violation will introduce new mixing between the neutral Higgs states and give rise to changes in the mass spectrum and couplings. We investigate these effects in light of the newly discovered Higgs boson, as its measured properties provides new limits on the Higgs sector
Evolution is a fundamental and crucial part of life that hinges on two central properties: robustness and evolvability. Robustness is required to maintain essential traits despite mutations while evolvability produces novel traits that might prove beneficial in survival. While both robustness and evolvability are necessary, embracing them simultaneously seemingly leads to an inherent conflict due
We investigate the ground-state energy of the pi(-)p atom (pionic hydrogen) in the framework of QCD + QED. In particular, we evaluate the strong energy-level shift. We perform the calculation at next-to-leading order in the low-energy expansion in the framework of the relevant effective field theory. The result provides a relation between the strong energy shift and the pion-nucleon S-wave scatter
Aims. This work reports oscillator strengths for transitions of astrophysical interest in singly ionized rhodium. Methods. Seventeen radiative lifetimes in Rh+ have been measured with the time-resolved laser-induced fluorescence technique and combined with theoretical branching fractions calculated using a relativistic Hartree-Fock model including core-polarization effects to obtain oscillator str
We use one-loop Heavy Meson Chiral Perturbation Theory (HMChPT) as well as a relativistic formulation to calculate the chiral logarithms m(pi)(2) log (m(pi)(2)/mu(2)) contributing to the formfactors of the semileptonic B -> pi decays at momentum transfer q(2) away from q(max)(2) = (m(B) - m(pi))(2). We give arguments why this chiral behaviour is reliable even in the energy regime with hard or fast
In high energy collisions saturation and multiple collisions are most easily accounted for in transverse coordinate space, while analyses in momentum space have been more suitable for calculating properties of exclusive final states. In this paper I describe an extension of Mueller's dipole cascade model, which attempts to combine the good features of both these descriptions. Besides saturation it
We consider electroweak Higgs plus three jets production at NLO QCD beyond strict VBF acceptance cuts. We investigate, for the first time, how accurate the VBF approximation is in these regions and within perturbative uncertainties by a detailed comparison of full and approximate calculations. We find that a rapidity gap between the tagging jets guarantees a good approximation, while an invariant
