Description
This track delves into theoretical and experimental efforts to uncover new physics beyond the Standard Model. Discussions include searches for supersymmetry, axions, extra dimensions, and other exotic phenomena at both colliders and non-collider experiments.
There is current interest in searching for beyond the standard model particles produced in association with a top quark pair, $t\bar{t} + X(X\rightarrow t \bar{t})$. This project focuses on a top-philic $Z’$ resonance model that may significantly enhance the $t\bar{t}t\bar{t}$ cross section. The all-hadronic channel is explored in the resolved regime using a novel machine learning algorithm,...
Non-linear scalar-tensor theories of modified gravity have been considered as candidates for dark matter and dark energy. Often, they possess screening mechanisms which allow them to evade detection from local experiments. Much is understood of their classical behaviour, but their quantum nature is relatively unexplored. We discuss a Green's function method for obtaining the leading order...
Axions are a wave-like dark matter candidate, first proposed to solve the strong CP problem of quantum chromodynamics. Axions have many properties currently expected of dark matter, with the last decade seeing the start of many axion experiments and collaborations across the world.
A brief summary on the aims, design, and status of the Quantum Sensors for the Hidden Sector (QSHS) axion dark...
Searches for rare decays of $B$ mesons into final states including four or six muons are performed using proton-proton collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 5.6 fb$^{-1}$. These decays are experimental signatures of hierarchical sectors beyond the Standard Model proceeding via flavor-violating heavy vectors and a set of light...
Many BSM models predict the existence of neutrally-charged long-lived particles (LLPs) with macroscopic lifetimes. When these LLPs decay back into SM particles within the ATLAS fiducial volume, they leave a striking signature in the form of displaced vertices (DVs). Due to its large size and precise tracking capabilities, the ATLAS muon spectrometer (MS) is a powerful tool for LLP...
The ATLAS Collaboration has performed a range of searches for supersymmetry (SUSY) which have produced null results and extensive limits on sparticle masses in simplified scenarios. However, many SUSY scenarios could have evaded detection through a richer phenomenology not captured by simplified models. I will present the constraints from Run 2 ATLAS searches for the electroweak production of...
Trigger-Level Analyses are an alternative strategy to record data and trigger on low-mass or low-momentum final states with the ATLAS detector. The premise of the workflow is to save minimal information comprised of only the trigger-level objects needed to reconstruct final state processes, and the information needed to calibrate those objects. This reduces the size of events stored to disk,...
A search is performed for long-lived particles decaying to pairs of muons by the CMS experiment recording proton-proton collisions at a centre-of-mass energy of 13.6 TeV at the LHC. The data is collected using a special stream which stores collision event information from 2022 and 2023 produced only by the High Level Trigger (HLT) system of CMS, thereby reducing the size of an event. This...
MAGIS and AION are a pair of next-generation quantum sensors that aim to explore fundamental physics with atom interferometry. This new experimental regime is capable of probing a diverse range of physical phenomena by creating unprecedented macroscopic superpositions of matter waves, including detecting mid-band (0.1-10 Hz) gravitational waves, testing theories of wave-function collapse,...
The proposed AN Underground Belayed In-Shaft (ANUBIS) experiment aims to search for long-lived particles within ATLAS underground cavern as a valuable addition to the dark matter programme at the CERN Large Hadron Collider. A prototype detector, proANUBIS, has been installed in ATLAS’ cavern and has been collecting data since 2024. This data will allow for studies of the expected backgrounds...
The discovery of the Higgs boson at 125 GeV has provided profound insights into the origin of fundamental particle masses in the Standard Model and the mechanism of electroweak symmetry breaking. However, theories beyond the Standard Model suggest the potential existence of additional Higgs bosons in extended parameter spaces. Intriguingly, Run 2 data from both the CMS and ATLAS experiments ...
Two-Higgs-Doublet-Models are theoretical extensions of the standard model that can account for some of its unanswered questions, for example the source of the matter/antimatter asymmetry in the Universe. They predict 5 bosons, the scalar/pseudoscalar H/A and the charged H+ and H-, alongside the h (the standard model Higgs boson). This talk will present the (currently blind) search for the...
Despite extensive efforts by many High Energy Physics experiments, no significant evidence for New Physics (NP) has been found. Novel analysis techniques, such as unsupervised Machine Learning (ML), have been proposed to try and extend the reach of these searches. This analysis uses unsupervised ML algorithms to perform event-based Anomaly Detection (AD) to search for BSM physics using Run 2...
The experimental search for a neutron Electric Dipole Moment (EDM) provides an extremely sensitive probe for CP violating physics beyond the Standard Model. The most precise measurement comes from a PSI based experiment giving an upper bound of $1.8\times10^{-26}$ $e$cm (90% CL) on the neutron EDM, by measuring spin precession of ultracold neutrons generated from a solid deuterium source and...
