Adinda de Wit

The discovery of the Higgs boson in 2012, by the ATLAS and CMS experiments, was a success achieved with only a percent of the entire dataset foreseen for the LHC. It opened a landscape of possibilities in the study of Higgs boson properties, Electroweak Symmetry breaking and the Standard Model in general, as well as new avenues in probing new physics beyond the Standard Model. Six years after the discovery, with a conspicuously larger dataset collected during LHC Run 2 at a 13 TeV centre-of-mass energy, the theory and experimental particle physics communities have started a meticulous exploration of the potential for precision measurements of its properties. This includes studies of Higgs boson production and decays processes, the search for rare decays and production modes, high energy observables, and searches for an extended electroweak symmetry breaking sector. This report summarises the potential reach and opportunities in Higgs physics during the High Luminosity phase of the LHC, with an expected dataset of pp collisions at 14 TeV, corresponding to an integrated luminosity of 3 ab$^{-1}$. These studies are performed in light of the most recent analyses from LHC collaborations and the latest theoretical developments. The potential of an LHC upgrade, colliding protons at a centre-of-mass energy of 27 TeV and producing a dataset corresponding to an integrated luminosity of 15 ab$^{-1}$, is also discussed.

This report comprises the outcome of five working groups that have studied the physics potential of the high-luminosity phase of the LHC (HL-LHC) and the perspectives for a possible future high-energy LHC (HE-LHC).The working groups covered a broad range of topics: Standard Model measurements, studies of the properties ofthe Higgs boson, searches for phenomena beyond the Standard Model, flavor physics of heavy quarks and leptonsand studies of QCD matter at high density and temperature.The work is prepared as an input to the ongoing process of updating the European Strategy for Particle Physics,a process that will be concluded in May 2020.

The discovery of the Higgs boson in 2012, by the ATLAS and CMS experiments, was a success achieved with only a percent of the entire dataset foreseen for the LHC. It opened a landscape of possibilities in the study of Higgs boson properties, Electroweak Symmetry breaking and the Standard Model in general, as well as new avenues in probing new physics beyond the Standard Model. Six years after the discovery, with a conspicuously larger dataset collected during LHC Run 2 at a 13 TeV centre-of-mass energy, the theory and experimental particle physics communities have started a meticulous exploration of the potential for precision measurements of its properties. This includes studies of Higgs boson production and decays processes, the search for rare decays and production modes, high energy observables, and searches for an extended electroweak symmetry breaking sector. This report summarises the potential reach and opportunities in Higgs physics during the High Luminosity phase of the LHC, with an expected dataset of pp collisions at 14 TeV, corresponding to an integrated luminosity of 3 ab$^{-1}$. These studies are performed in light of the most recent analyses from LHC collaborations and the latest theoretical developments. The potential of an LHC upgrade, colliding protons at a centre-of-mass energy of 27 TeV and producing a dataset corresponding to an integrated luminosity of 15 ab$^{-1}$, is also discussed.

Special forces selection is a highly demanding process that involves exposure to high levels of psychological and physical stress resulting in dropout rates of up to 80%. To identify who likely drops out, we assessed a group of 249 recruits, every week of the program, on their experienced psychological and physical stress, recovery, self-efficacy, and motivation. Using both ordinary least squares regression and state-of-the-art machine learning models, we aimed to find the model that could predict dropout best. Furthermore, we inspected the best model to identify the most important predictors of dropout and to evaluate the predictive performance in practice. Via cross-validation, we found that linear regression performed best while remaining interpretable, with an Area Under the Curve (AUC) of 0.69. We also found that low levels of self-efficacy and motivation were significantly associated with dropout. Additionally, we found that dropout could often be predicted multiple weeks in advance and that the AUC score may underestimate the real-world predictive performance. Taken together, these findings offer novel insights in the use of prediction models on repeated measurements of psychological and physical processes, specifically in the context of special forces selection. This offers opportunities for early intervention and support, which could ultimately improve selection success rates.

Selecting the right individuals for a sports team, organization, or military unit has a large influence on the achievements of the organization. However, the approaches commonly used for selection are either not reporting predictive performance or not explainable (i.e., black box models). In the present study, we introduce a novel approach to selection research, using various machine learning models. We examined 296 recruits, of whom 214 dropped out, who performed a set of physical and psychological tests. On this data, we compared four machine learning models on their predictive performance, explainability, and stability. We found that a stable rule-based (SIRUS) model was most suitable for classifying dropouts from the special forces selection program. With an averaged area under the curve score of 0.75, this model had a high predictive performance, and was most explainable and stable compared to the alternative models. Furthermore, we found that both physical and psychological variables were related to dropout. More specifically, a lower score on the 2800 meters time, sprint time, connectedness, skin folds, and fear of failure were most strongly associated with graduation. We discuss how researchers and practitioners can benefit from these insights.

Prospects for measurements of the properties of the standard model Higgs boson and searches for beyond the standard model Higgs bosons with the CMS experiment at the HL-LHC are presented. The studies are based on projections of existing analyses performed by CMS at $\sqrt{s}=13$ TeV.

A group of Early-Career Researchers (ECRs) has been given a mandate from the European Committee for Future Accelerators (ECFA) to debate the topics of the current European Strategy Update (ESU) for Particle Physics and to summarise the outcome in a brief document [1]. A full-day debate with 180 delegates was held at CERN, followed by a survey collecting quantitative input. During the debate, the ECRs discussed future colliders in terms of the physics prospects, their implications for accelerator and detector technology as well as computing and software. The discussion was organised into several topic areas. From these areas two common themes were particularly highlighted by the ECRs: sociological and human aspects; and issues of the environmental impact and sustainability of our research.

Abstract A review of closed-in wells in the Northern Swamp Area (NSA) of The Shell Petroleum Development Company of Nigeria Ltd (SPDC) in 2003 revealed huge opportunities in closed in wells that can be realised at relatively low costs through the application of new technologies. Initial estimates of these opportunities in the Northern Swamp Area (NSA) were about 174 intervals with potential gains of some 53 Mbopd (unrisked) and costs of circa $27 million. A detailed review of these notional candidates was carried out by a multi-disciplinary team. The technically feasible and economically viable rigless (non-rig related) opportunities were matured for execution in 2004. This paper presents results of the rigless activities matured and executed in 2004. From December 2003 to November 2004, 67 jobs were executed with actual total gains in potential of 44,889 bopd against 34,869 bopd planned. Annual average gains of 20Mbopd were realized from these activities against a plan of 14Mbopd. The jobs were executed at F$13.6 million, and Unit Technical Cost (UTC) of $2.07 per barrel. This project has a Net Present Value (NPV) of F$112 million. A number of new technologies and cost savings initiatives were implemented during the execution of these activities.