Toward a first full test of holographic cosmological models
This project is focused on the study of field theories relevant for building holographic cosmological models. These models use three dimensional QFT to model holographically the laws of physics in the very early universe and make predictions for cosmological observables such as the cosmic microwave background (CMB). Our analysis aims to provide the predictions of […]
What Role Does Interchange Reconnection Play in the Formation of Magnetic Switchbacks?
Observations from NASA’s Parker Solar Probe (PSP), launched in 2018, have revealed that close to the Sun the solar wind is tremendously variable, much more so than further out in the Heliosphere. This variability primarily takes the form of local reversals of the usually radial magnetic field known as magnetic switchbacks. These structures seem to […]
Hadron Resonances from Lattice QCD
Understanding and obtaining predictions from Quantum Chromodynamics (QCD), the theory of strongly-interacting quarks and gluons, is one of the foremost problems in particle physics. The vast majority of ordinary strongly-interacting matter is composed of protons and neutrons, themselves composed of light up and down quarks. However, the spectrum of QCD also contains excitations involving other […]
Kink-unstable flux ropes in three-dimensional, multi-fluid, partially ionised plasma
Andrew Hillier, Ben Snow, Giulia Murtas The solar atmosphere is a complex and chaotic plasma environment, rife with explosive phenomena driven by the complex magnetic structure undergoing topological changes and releasing this stored energy through a process known as magnetic reconnection. This process readily occurs in the twisted (kinked) magnetic flux ropes that exist throughout […]
Discontinuous Galerkin methods and time implicit solver applied to various astrophysical problems
Project dp048 – PI I. Baraffe – Data Intensive Cluster System in Leicester & Cambridge Despite being the most observed star in the Universe, many open questions remain regarding the properties of convection and waves in the deep interior of the Sun. Sophisticated numerical simulations can unveil some important properties and provide a better understanding […]
Long term planet migration simulations demonstrate an attractor for gas giant planets in 1-10 AU range
The conventional picture of giant planet migration in protoplanetary discs involves an inexorable inspiral towards the star through the process of Type II migration, thus providing a popular scenario for the creation of hot Jupiters. In Scardoni et al 2022[1] we explored very long term (0.6M planetary orbits)[2] simulations of Type II migration in the […]
Vertical cross-section taken from a 3D stellar simulation
The image shows a vertical cross-section taken from a 3D stellar simulation run on the DiRAC Memory Intensive Service. It is possible to see the turbulent motions of the plasma inside the star and how the chemical composition is transported and mixed, represented by the abundance of neon in colour scale (red more abundant, blue […]
Predicting Signatures of Luminous Remnants for Type Iax Supernovae
Fionntán Callan, Stuart Sim, Christine Collins, Luke Shingles, Joshua Pollin Astrophysics Research Centre, Queen’s University Belfast, Northern Ireland Type Ia supernovae (SNe Ia) are extremely luminous astrophysical events that arise from the thermonuclear explosions of white dwarf stars. They play a number of key roles in astrophysics including acting as cosmological distance indicators, contributing substantially […]
HPQCD: hints of new physics in rare B decays
A key aim of the worldwide particle physics programme is to find evidence of new physics beyond our current Standard Model (SM) that would allow us to develop a more complete theory of fundamental physics. B meson decays are a good place to look because some of these are very rare in the SM but […]
The statistical properties of stars at redshift, z = 5, compared with the present epoch
Matthew Bate (University of Exeter) The distribution of stellar masses, known as the initial mass function (IMF), is of central importance in astrophysics, due to the fact that the radiative, chemical and mechanical feedback from a star depends strongly on its mass. Despite many observational studies, there is little evidence for variation of the IMF […]