QCD challenges from pp to AA collisions: 4th edition.

This paper is a write-up of the ideas that were presented, developed and discussed at the fourth International Workshop on QCD Challenges from pp to AA, which took place in February 2023 in Padua, Italy. The goal of the workshop was to focus on some of the open questions in the field of high-energy heavy-ion physics and to stimulate the formulation of concrete suggestions for making progresses on both the experimental and theoretical sides. The paper gives a brief introduction to each topic and then summarizes the primary results.

The role of multi-parton interactions in doubly-heavy hadron production.

Beauty and charm quarks are ideal probes of pertubative Quantum Chromodymanics in proton-proton collisions, owing to their large masses. In this paper the role of multi-parton interactions in the production of doubly-heavy hadrons is studied using simulation samples generated with Pythia, a Monte Carlo event generator. Comparisons are made to the stand-alone generators BcVegPy and GenXicc.

VINCIA for hadron colliders.

We present the first public implementation of antenna-based QCD initial- and final-state showers. The shower kernels are [Formula: see text] antenna functions, which capture not only the collinear dynamics but also the leading soft (coherent) singularities of QCD matrix elements. We define the evolution measure to be inversely proportional to the leading poles, hence gluon emissions are evolved in a [Formula: see text] measure inversely proportional to the eikonal, while processes that only contain a single pole (e.

Implications of direct dark matter constraints for minimal supersymmetric standard model Higgs boson searches at the Tevatron.

In regions of large tanbeta and small mAlpha, searches for heavy neutral minimal supersymmetric standard model (MSSM) Higgs bosons at the Tevatron are promising. At the same time, rates in direct dark matter experiments, such as CDMS, are enhanced in the case of large tanbeta and small mAlpha. As a result, there is a natural interplay between the heavy, neutral Higgs searches at the Tevatron and the region of parameter space explored by CDMS.