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We show that the characteristic p⊥ spectrum yields valuable information for the test of models for the production of narrow graviton resonances in the TeV range at LHC. Furthermore, it is demonstrated that in those scenarios the parton showering formalism agrees with the prediction of NLO matrix element calculations.

This document describes the first proof-of-concept version of the PYTHIA7 program. PYTHIA7 is a complete re-write of the PYTHIA program in C++. It is mainly intended to be a replacement for the `Lund' family of event generators, but is also a framework with a structure suitable for implementing any event generator model. In this document, the structure of the program is presented both from the use

Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, visible through emission lines. We report a stable 123.4-minute periodic variation in the strength and shape of the Ca II emission line profiles originating from the debris disc around the white dwarf SDSS J122859.93+10403

Jupiter Trojans are a resonant asteroidal population characterised by photometric colours that are compatible with trans-Neptunian objects, high inclinations, and an asymmetric distribution of the number of asteroids between the two swarms. Different models have been proposed to explain the high inclination of the Trojans and to interpret their relation with the Trans-Neptunian objects, but none o

The dynamical stability of tightly packed exoplanetary systems remains poorly understood. While a sharp stability boundary exists for a two-planet system, numerical simulations of three-planet systems and higher show that they can experience instability on timescales up to billions of years. Moreover, an exponential trend between the planet orbital separation measured in units of Hill radii and th

Primordial black holes formed through the collapse of cosmological density fluctuations have been hypothesized as contributors to the dark matter content of the Universe. At the same time, their mergers could contribute to the recently observed population of gravitational-wave sources. We investigate the scenario in which primordial black holes form binaries at late times in the Universe. Specific

gregor.traven@astro.lu.se.

Finding life on a planet other than the Earth would easily be one of the greatest discoveries of all time, particularly so if it is found outside our Solar System. To do so, we must understand the conditions required for life to emerge and develop. Whilst an enormous amount of research has gone into understanding the requirements for life on Earth to have spontaneously arisen and then evolved, muc

In the hadronic decays of Z0, gluon emission leads to the appearance of the longitudinal component of the fragmentation function, FL. Measurement of FL and the transverse component, FT, could thus provide insight into the gluon fragmentation function. However, hadronization corrections at low cursive Greek chi can be significant. Here we present a method of accounting for such corrections, using t