Multiple scatterings of Lyman series photons
PI: Shikhar Mittal The period when the first stars began to form, known as cosmic dawn, remains one of the least explored epochs in the history of the Universe. A powerful probe of this era is the 21-cm signal, a faint radio emission from neutral hydrogen that provides a unique window into both cosmic dawn […]
Beam Modelling and Emulation for the Radio Experiment for the Analysis of Cosmic Hydrogen
PI: Harry Bevins Project Title: Beam Modelling and Emulation for REACH Background: One of the most pressing open questions in observational cosmology concerns the nature of the first stars and galaxies. The Cosmic Dawn and Epoch of Reionization (300 million to one billion years after the Big Bang) mark the transformation of the Universe from […]
The status of sub-GeV dark matter: a global analysis with GAMBIT
PI: Will Handley Sub-GeV dark matter particles produced via thermal freeze-out evade many constraints on heavier candidates but face a multitude of new constraints from laboratory experiments, astrophysical observations and cosmological data. In 2025, Balan, Kahlhoefer, Gonzalo et al. (arXiv:2405.17548, JCAP 01 053) used DiRAC CSD3 to perform the first comprehensive global analysis of sub-GeV […]
unimpeded: a public nested sampling database for cosmology
PI: Will Handley Bayesian model comparison and tension quantification are central to modern cosmology, but require the computationally expensive calculation of Bayesian evidences via nested sampling. In 2025, Ong & Handley released unimpeded (arXiv:2511.04661, arXiv:2511.05470), a publicly available Python library and data repository of pre-computed nested sampling chains funded by DiRAC DP192 and DP264. Using […]
The nonlinear magnetic dynamo in accretion discs
PI: Mattias Brynjell-Rahkola Magnetic fields have a strong influence on the gas dynamics in accretion discs around stars and black holes. Through magnetohydrodynamic (MHD) instabilities, they may lead to turbulence in the disc that significantly increases the radial transport of angular momentum. In zero-net flux discs, large-scale magnetic fields are generated by dynamos. A common […]
Understanding large scale density features in the largest astrophysical entities in the Universe
PI: PRAKRITI PALCHOUDHURY Title: Understanding large scale density features in the largest astrophysical entities in the Universe Resource allocation: CSD3 1. Characterising scales of coherent density features due to injected magnetized outflows into a magnetized intracluster medium – The origin and sustenance of a wide range of coherent structures in temperature and density observed in […]
Magnetohydrodynamics of distorted accretion discs
PI: Loren E. Held Project dp377, which started in April of 2025, is devoted to exploring the (magneto)-hydrodynamics of distorted accretion disks. Simple models of accretion disks (i.e. disks of gas or dust around young stars or compact objects such as black holes) often treat the disk as being flat (planar). However, many disks in […]
Probing Black Hole Accretion: Outflows and Radiative Cooling in GRMHD Simulations
PI: Dr Tiago Costa Co-I Dr Ivan Almeida AGN feedback operates across an extremely large range of spatial scales, from the event horizon of supermassive black holes (SMBHs) to clusters of galaxies, making it challenging to model within a single, physically consistent framework. A major di!culty lies in connecting the launching of relativistic jets and […]
The Evolution of the Milky Way and Andromeda
PI: Victor P Debattista We showed (Debattista et al. 2025, MNRAS, 537, 1620) that the azimuthal variations in mean stellar metallicity observed in the Milky Way can be attributed to spiral structure. We demonstrated that these azimuthal variations can be traced to more metal-rich stars being, on average, kinematically cooler. Since cooler populations support spiral […]
AZAHAR Cosmological Simulations Unveil the Origin of Bursty Star Formation in High-Redshift Galaxies
PI: Debora Sijacki The James Webb Space Telescope (JWST) is revolutionizing our understanding of the properties of galaxies all the way back to the very early Universe, with a leap in sensitivity, especially in measuring spectra, of more than three orders of magnitude. JWST observations have led to numerous surprising results and have enabled new […]