This contribution is a historical reflection on the rise of the dark matter hypothesis. Specifically, it focusses on understanding how the problem of dark matter came to matter in the early 1970s, decades after it had been famously introduced by Fritz Zwicky (1933). What were the conditions that brought about new conclusions on the existence of dark matter in this period? I will argue that the...
The local dark matter density is required to interpret results from direct detection experiments, whether they are searching for WIMPs, sterile neutrinos, or axions. Here I give an update to our ongoing project to determine the local DM density using stellar motions and our advanced Jeans equation based analysis. This includes our recent measurement using SDSS-SEGUE G-dwarfs, and a look ahead...
An anomalous excess at energies of a few GeV is seen in the Fermi-LAT data.
Being well fit by an NFW profile and centered on the Galactic Center, this so-called Galactic Center Excess (GCE) has generated a lot of excitement over the past years due to its consistency with a dark matter origin. However, there exist viable astrophysical explanations, most notably unresolved millisecond pulsars....
Future cosmic microwave background (CMB) and large-scale structure (LSS) observations will provide us with percent-level measurements of the radiation content of the universe. I will show this by discussing current observational constraints and, in particular, providing forecasts of the capabilities of future CMB and LSS experiments such as CMB-S4 and DESI. In addition, I will provide...
Indirect dark matter (DM) searches are one of the fundamental techniques used to probe the particle nature of DM. Given the increasing interest in the community in non-WIMP scenarios, it is vital to systematically reconsider optimal strategies for observation campaigns of current and future telescopes that cover a large range of DM models and signals. In this endeavour, it is important to...
Template fitting of the gamma-ray sky has been quite successful in both understanding existing sources of emission and discovering new sources, such as the Fermi Bubbles and the GeV excess towards the center of the Milky Way. However, existing models still yield formally poor fits to the data with significant remaining residuals, which makes quantitative comparisons between different models...
Clusters of galaxies should host a significant amount of relativistic cosmic-ray protons accelerated by structure formation shocks during their assembly history, and re-accelerated by turbulence in merging clusters. The quest for the pion-decay emission from hadronic interaction of these relativistic protons with the ambient gas has so far been inconclusive. Nevertheless, gamma-ray...
Neutrino interactions, though feeble, are tremendously important in particle physics and astrophysics. Yet, at neutrino energies above 350 GeV there has been, up to now, no direct experimental information on neutrino interactions, only predictions. Now, we can measure the neutrino-nucleon cross section above 10 TeV, thanks to the recent discovery of high-energy astrophysical neutrinos by...
Two years ago, the AMS collaboration released the most precise measurement of the cosmic ray positron flux. It confirms that pure secondary predictions fall below the data above 10 GeV, suggesting the presence of a primary component, e.g. annihilations of WIMPs dark matter. Most analyses have focused on the high-energy part of the spectrum, disregarding the GeV energy region where cosmic ray...
The dominant models that can describe the non - thermal radiation by high energy astrophysical objects, can be divided into two categories, i.e. the leptonic and the hadronic ones. The former one suggests that the high energy radiation is produced by physical processes associated with a population of highly relativistic electrons. On the other hand, the hadronic model assumes that the observed...
Molecular hydrogen has been identified as a search ground for physics beyond the Standard Model. This is complementary to searches motivated by high-energy and astroparticle physics, as we search for subtle effects at the low-energy scale in the spectra of simple molecules. The quantum level structure of the hydrogen molecule can now be calculated to very high precision. These theoretical...
