The strongest constraints on sub-GeV feebly interacting particles are typically derived from beam dump facilities. Historically, these constraints rely on a conservative (under)estimate of the flux focussing only on production within the first interaction length. In this talk I will explain how to consistently include production from the subsequent electromagnetic cascade in the target....
The Coherent CAPTAIN Mills (CCM) experiment uses a 10-ton liquid argon scintillation detector at Los Alamos National Laboratory to search for physics beyond the standard model. Such physics includes light dark matter (LDM), axion like particles (ALPs), and Dark Sector coupling to Meson Decay (DSCMD) produced by the LANSCE accelerator. The Lujan Center delivers a 100-kW, 800 MeV, 290 ns wide...
PADME is a fixed-target, missing-mass experiment originally designed to search for dark photons using a beam of positrons with energy up to 500 MeV. The detector, located at the Laboratori Nazionali di Frascati, in Italy, has already collected initial physics data over the last few years. More recently, the experiment has been adapted to perform a direct search for on-shell X17 production....
Paleo-detectors have been proposed to search for new physics through damage tracks formed by traversing recoiled nuclei in minerals deep underground, leveraging its high exposure time (~Gyr). Paleo-detection is expected to have a very low signal-to-background ratio, it is therefore particularly important to accurately model the expected signals. In previous studies, a one-to-one relationship...
An early dark energy (EDE) component during big bang nucleosynthesis (BBN) affects some observables like the deuterium abundance (D/H), helium fraction ($Y_p$), and the effective relativistic degrees of freedom ($N_{\rm eff}$). Thus, we propose a model of EDE present during the BBN epoch where the EDE remains constant until a critical time, after which it transitions into either coupled...
I present a novel mechanism for creating primordial black holes and MACHOs via a self interacting dark matter. A heavy dissipative dark sector can come to dominate the universe, creating an early matter dominated era prior to Big Bang Nucleosynthesis (BBN). At this time the dark matter can form halos which persist after the phase transition back to radiation domination, and slowly collapse...
Semi-visible jets (SVJs) arise in strongly interacting dark sector, resulting in jets geometrically enclosing dark hadrons and overlapping with missing transverse momentum direction. The first experimental results from ATLAS and CMS are public, and we will start with a quick debriefing. There are proposals to look at more specialised SVJ signatures, we will focus on SVJ with heavy flavours,...
QFT shows that fundamental constants are not fixed but vary with energy scales. This opens the possibility that in the early universe, gauge couplings may differ from those predicted by the Standard Model, potentially leading to observable non-standard phases. The low-energy spectrum of generic models that aim to archive this usually has a light singlet that couples through higher-dimensional...
Telescope observations of background radiation in the Milky Way point to an anomalous excess in ultraviolet, radio, and x-ray signals. The unconventional Axion Quark Nugget (AQN) dark matter model may provide an interpretation for this as-yet-unexplained excess. The model proposes that dark matter is dominated by macroscopic composite objects of nuclear density, in the form of matter and...
A QCD axion with a decay constant below $ 10 ^{ 11} ~{\rm GeV} $ is a strongly-motivated extension to the Standard Model, though its relic abundance from the misalignment mechanism or decay of cosmic defects is insufficient to explain the origin of dark matter. Nevertheless, such an axion may still play an important role in setting the dark matter density if it mediates a force between the...
