From Atoms to Machine-Learned Molecules: Dark Matter Detection at Low Energies

• Jack Shergold

Probing sub-GeV dark matter scattering through sidereal modulation

• Tetiana Kozynets

Beyond WIMPs in Direct Dark Matter searches (xenon realm)

• Sergey Burdin

Dark matter at the smallest scales: New signatures of particle dark matter

• M. Sten Delos

I will present prompt cusps, a recently identified class of compact dark matter structures with ρ∝r^-1.5 density profiles that form at the onset of structure formation and persist at halo centers. These systems enable new constraints on warm dark matter from dwarf galaxy kinematics, strengthen limits on annihilating dark matter, and offer detection prospects for general cold dark matter models. Next, I will discuss how enhanced primordial perturbations can form halos during the radiation era that are compact enough to be detected with microlensing. Finally, I will present results on primordial black hole (PBH) dark matter from a new cosmological simulation that fully resolves individual PBH dynamics. Interactions randomize binary orbits, dramatically altering gravitational-wave predictions, while a hot dark matter component emerges that suppresses structure growth up to galactic scales.

WIMP Dark Matter and New-Physics Interpretations of the PTA Signal are Incompatible

• Yann Gouttenoire

Explaining the large amplitude of the nano-Hertz stochastic gravitational-wave background observed by pulsar timing arrays (PTAs) typically requires extremely energetic primordial sources. Such mechanisms generically produce large curvature perturbations, which subsequently collapse into ultra-compact mini-halos (UCMHs). If dark matter consists of weakly interacting massive particles (WIMPs), the high densities inside UCMHs lead to efficient dark-matter annihilation, generating potentially observable photon and neutrino fluxes. I will show that, for several proposed primordial explanations of the PTA signal, including curvature-peak scenarios, first-order phase transitions, and domain-wall dynamics, the predicted fluxes from the resulting UCMH population exceed current observational bounds. These results therefore place strong tension between WIMP dark matter and new-physics interpretations of the PTA signal.

Astrophysical probes of ultralight particles: pulsar spindown, birefringence, and superradiance

• Tanmay Poddar

Community discussion on navigating an evolving funding landscape

Ultralight Dark Matter at Colliders and Quantum Sensors

• Martin Bauer

Electroweak Dark Matter: Generalised Framework and Direct and Indirect Search Prospects

• Spencer Griffith

Status report on the QSHS axion search

• Ed Daw

Dark Showers from Sneaky Dark Matter

• Fatemeh Elahi

Probing the nature of dark matter with galaxies and Black Holes

• Malcolm Fairbairn

Stellar cooling limits on dark dimensions

• Henry Stubbs

Nearly 30 years since the ADD proposal to solve the hierarchy problem via large extra dimensions, such scenarios have seen a resurgence in interest in the context of the ‘dark dimension’ - an extra dimension of micron scale motivated by the swampland program. We will begin by reviewing the features of the dark dimension, including the possibility that dark matter could consist of Kaluza-Klein gravitons. We will then undertake a systematic study of the model-independent astrophysical constraints on large extra dimensions. These arise from stellar cooling through emission of Kaluza-Klein gravitons. Setting up the calculation from first principles in the context of thermal field theory leads to the identification of a process with no zero-temperature analogue: resonant plasma mixing. After studying a range of previously overlooked processes in red giants, horizontal branch stars, neutron stars, and supernovae, we find that for two or more extra dimensions the leading bounds come from the cooling of supernova 1987A.

Stellar microlensing constraints on Primordial Black Holes

• Anne Green

Searching for Dark Matter Microlensing Signals with Machine Learning

• Miguel Crispim Romao

Conference dinner

Talk

• Ashlea Kemp

Cosmological tests of the nature of dark matter

• Keir Rogers

The fundamental nature of dark matter so far eludes direct detection experiments, but it has left its imprint in the cosmic large-scale structure. Disentangling this imprint requires accurate modelling of structure formation in non-standard dark matter models, careful handling of astrophysical uncertainties and consistent observations in independent cosmological probes. I will review a multi-scale, multi-epoch test of the nature of dark matter combining state-of-the-art modelling with observations of the cosmic microwave background, galaxy clustering (redshift z < 2), the Lyman-alpha forest (2 < z < 5) and the high-redshift (z > 5) galaxy UV luminosity function from the Hubble and Webb Space Telescopes. I will discuss the extent to which cosmological data are more consistent in the presence of ultra-light axion dark matter. I will further discuss prospects for adjudicating the viability of axion models in observations of the galaxy and Milky Way sub-structure distributions by the transformative Vera C. Rubin Observatory.

Beyond WIMPs: Perspectives on Beyond Elastic Recoil Searches

• Jocelyn Monroe