Dark Matter 2025: From the Smallest to the Largest Scale

Session

Monday Afternoon I

Jun 2, 2025, 2:45 PM

Santander, Spain

45. Probing dark matter with strong lensing and the line of sight

Daniel Johnson (CNRS/University of Montpellier)

6/2/25, 2:45 PM

Galaxies, Dynamics and Cosmology

Contributed Talk

Gravitational lensing is a powerful tool for constraining the nature and distribution of dark matter. Strong lensing observations allow comparisons between the mass and light profiles of galaxies, and dark matter subhalos have been detected through their perturbations to lensed images. Weak lensing probes the matter power spectrum, and thus the abundance and behaviour of dark matter, as well...

55. Dark matter from extremely lensed stars at cosmological distances

Jose Maria Diego Rodriguez (IFCA)

6/2/25, 3:05 PM

Galaxies, Dynamics and Cosmology

Contributed Talk

Background stars at cosmological distances that appear near the critical curves of galaxy clusters can be magnified by extreme factors of O(1000) and be detectable in deep observations with the Hubble or James Webb space telescopes. The stellar nature of this objects can be confirmed thanks to microlensing by stars in the galaxy cluster that can temporarily boost the flux of the lensed star by...

77. Phasing-in dark matter

Henda Mansour (KIT)

6/2/25, 3:25 PM

DM Models and Theory

Contributed Talk

Despite being an elegant mechanism to explain Dark Matter (DM) production, freeze-in introduces challenges: If DM interacts via non-renormalizable operators, the predictions are highly sensitive to the initial conditions, such as the reheating temperature of the universe. These issues are particularly relevant in models in which the universe deviates from radiation domination and the entropy...

75. Towards realistic SIMP dark matter

Halvor Melkild (University of Oslo)

6/2/25, 3:45 PM

DM Models and Theory

Contributed Talk

The so-called "strongly interacting massive particles" (SIMPs) refer to a class of dark matter candidates with the relic abundance set by the 3$\to$2 interactions which allows for dark matter with sub-GeV masses, not yet strongly constrained by direct detection experiments. Interestingly, SIMP dark matter features relatively strong self-interactions that may explain the small-scale structure...

53. Cogenesis by QCD axion

EUNG JIN CHUN (Korea Institute for Advanced Study)

6/2/25, 4:05 PM

DM Models and Theory

Poster + Lightning Talk

We show how cogenesis of dark matter and baryon asymnmetry can arise from kinetic misalignment of the QCD axion. For this, we work out the DFSZ and KSVZ axion models associated with the type-I seesaw mechanism and the PQ inflacion.

44. Testing the dark origin of neutrino masses with oscillation experiments

Hong-Yi Zhang (Tsung-Dao Lee Institute)

6/2/25, 4:10 PM

DM Models and Theory

Poster + Lightning Talk

The origin of neutrino masses remains unknown to date. One popular idea involves interactions between neutrinos and ultralight dark matter, described as fields or particles with masses $m_\phi \lesssim 10\,\mathrm{eV}$. Due to the large phase-space number density, this type of dark matter exists in coherent states and can be effectively described by an oscillating classical field. As a result,...