Conveners
Parallel stream 2: Session 1
- Wilf Shorrock (Imperial College (GB))
- Teppei Katori (Queen Mary University of London)
- Antonin Vacheret (Imperial College London)
- Antonin Vacheret (Imperial College London)
Parallel stream 2: Session 2
- Paul Scovell (STFC)
- Paul Scovell (University of Oxford)
- Samuel Webb (Imperial College (GB))
- Jonathon Mark Langford (Imperial College (GB))
Parallel stream 2: Session 3
- Tracey Berry (University of London (GB))
- Mark Scott (Imperial College London)
- Wilf Shorrock (Imperial College (GB))
Long-lived particles feature in many extensions to the Standard Model that have been proposed to address some of its open questions. Decays of long-lived particles created in collider experiments would produce unique signatures that may have been overlooked by previous searches for promptly decaying particles.
A search for pairs of neutral long-lived particles (LLPs) decaying in the volume...
Higgs decay to a muon pair is the most promising way to probe Yukawa couplings to the second generation fermions at the LHC. Experimentally the analysis is challenging due to a small branching ratio (2.2*10^-4) and proceeds as a search for an excess at the Higgs mass in the dimuon invariant mass spectrum dominated by the irreducible Drell-Yan background. This talk presents the search with 79.8...
Since the discovery of the Higgs boson in 2012, the observed production and decay modes have all been related to its coupling to gauge bosons and to third generation fermions. The focus is now shifting towards the Higgs boson couplings to the second generation fermions, in particular to muons, but the first generation is much less explored. This talk will present the ongoing efforts within the...
The IceCube Neutrino Observatory detects astrophysical neutrinos with energies above TeV scales which provides the first solid evidence for astrophysical neutrinos from cosmological accelerators. Here we describe The High Energy Starting Event (HESE) selection and why it is useful for probing the high energy astrophysical landscape. With higher statistics taken over 7.5 years, we have been...
LUX-ZEPLIN (LZ) is a dark matter direct detection experiment under construction at the Sanford Underground Research Facility in Lead, South Dakota. The dual-phase TPC at its core will contain seven tonnes of active liquid xenon to search for Weakly Interacting Massive Particles (WIMPs). Fabrication and assembly operations are on track to start a 1000-day science run in 2020 with a fiducial...
LUX-ZEPLIN (LZ) is a next-generation two-phase xenon TPC detector operating at 4850 feet below ground with an active mass of 7 tonnes. The primary goal of LZ is to search for low-energy interactions from the dark matter halo in our galaxy — hypothesised to be in the form of Weakly Interacting Massive Particles (WIMPs). Operating for 1000 days and using a 5.6-tonne fiducial mass, LZ is...
DEAP-3600 is single-phase liquid argon (LAr) direct-detection dark matter experiment, operating 2 km underground at SNOLAB, Sudbury, Canada. The detector consists of 3279 kg of LAr contained in a spherical acrylic vessel.
In this talk, a summary of the second dark matter search analysis of a 758 tonne-day exposure will be presented with emphasis given to modelling the detector backgrounds.
The large amount of data collected at the Large Hadron Collider in its second phase of running, colliding protons at an unprecedented center of mass energy of 13 TeV, gives us the tremendous opportunity to conduct measurements of vector boson plus jets (V+jets) processes in regions of phase space that were previously limited.
This kind of processes play a key role in precision tests of the...
If dark matter interacts weakly with standard model particles it could be produced at the LHC and therefore could be observed with the ATLAS detector. WIMP dark matter would not interact with the detector and therefore would leave a signature involving large amounts of missing transverse momentum. There are a number of models assume a mediator which couples to both dark matter and the...
The aim of this analysis is to study the process pp-> J/psi + photon + X, in order to understand the production mechanisms of this final state, and possibly to assess some information on the spin structure of the gluon distribution inside the proton. Analysing the subprocess g+g->J/psi + photon there is the prospect of seeing azimuthal modulations in the Collins-Soper frame, induced by the...
In this talk a search for a Higgs boson cascade in the context of the two-Higgs-Doublet Model is presented. In this cascade, a heavy Higgs boson A decays to ZH, where H is another heavy Higgs boson with mass > 125 GeV. Subsequently, the Z boson decay leptonically and the H boson into a bb pair. The search is motivated by the mechanism which generates the matter-antimatter asymmetry in the...
The DEAP-3600 detector, based 2km underground at SNOLAB (Sudbury, Canada) is a dark matter direct detection experiment. The detector is a single phase liquid argon (LAr) target, of 3279 kg mass. In this talk, the results of a dark matter search analysis of 758 tonne-days will be presented. No candidate signal events were observed in the WIMP region of interest, resulting in the leading limit...
Supersymmetry (SUSY) is one of numerous, and one of the most famous, theoretical extensions to the Standard Model aiming to answer open questions in particle physics, such as the nature of dark matter and the origin of the electroweak symmetry breaking. SUSY extends the particle spectrum of the SM such that each SM particle has at least one supersymmetric partner. Mixtures of the SUSY partners...
We present a method for non-parametric, Bayesian neutrino event reconstruction for the Super-Kamiokande detector. Particle properties are determined in a way where the number of Cherenkov rings to be reconstructed, and therefore the number of parameters, is one of the unknowns. We discuss Bayesian model selection with Markov Chain Monte Carlo, future scalability and the issues surrounding...
The Moedal Experiment uses Passive Nuclear Track Detectors (NTDs) to look for magnetic monopoles, and other heavily ionising exotic particles at the LHC. Through a process of chemical etching, the latent ionisation tracks of particles can be converted into microscopically visible known as etch-pits.
This study looks at CNN image recognition for identifying particle etch pits in an NTD foil...
The observation of a new resonance would be powerful evidence for new physics beyond the Standard Model. Searching for such new resonances at the LHC via their decay to pairs of quarks is a natural and broad search for new physics. In order to reduce QCD background and enhance our sensitivity to particles which preferentially couple to mass we search for particles which decay to pairs of...
A search is conducted for non-resonant high-mass phenomena in dielectron and dimuon final states. The search uses the full Run-2 proton-proton collision data collected between 2015 and 2018 at sqrt{s} = 13 TeV by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 140 fb-1. A novel approach involving a functional form is fitted to the dilepton invariant mass...
