Developing a set of jet substructure observables to probe beyond-LL aspects of QCD showers
Looking for alternative scale-free observables in multijet events with the aim to identify when matrix element or parton showers must be used
Sabrina Sacerdoti is a Ph.D. student from Universidad de Buenos Aires, on a three-month MCnet studentship in the Durham team.
Impact of systematic uncertainties and their correlations on generator tunes
Simone Amoroso is a Ph.D. student from the University of Freiburg, on the ATLAS experiment, on a three-month MCnet studentship in the CERN team.
Developing a new model for colour reconnections in PYTHIA 8, based on SU(3) group weights
Colour reconnections have emerged as one of the main uncertain aspects of soft hadron-hadron collider physics, with significant implications for minimum-bias and underlying-event physics, as well as for precision measurements, most importantly the determination of the top quark mass in hadronic final states. We argue that a vital missing ingredient in current models is an understanding of the implications of QCD coherence on the process of hadronization, especially in the context of multiple parton interactions (MPI).
R-parity violating SUSY and generic BSM models in Pythia 8
We describe the implementation of supersymmetric models in PYTHIA 8, including production and decay of superparticles and allowing for violation of flavour, CP, and R-parity. We also present a framework for importing generic new-physics matrix elements into PYTHIA 8, in a way suitable for use with automated tools. We emphasize that this possibility should not be viewed as the only way to implement new-physics models in PYTHIA 8, but merely as an additional possibility on top of the already existing ones.
Energy scaling of min-bias pp collisions
Results published here.
Forward-backward and azimuthal correlations in pp collisions
Measurements of inclusive observables, such as particle multiplicities and momentum spectra, have already delivered important information on soft-inclusive ("minimum-bias") physics at the Large Hadron Collider. In order to gain a more complete understanding, however, it is necessary to include also observables that probe the structure of the studied events. We argue that forward-backward (FB) correlations and event-shape observables may be particulary useful first steps in this respect.