Periodic Reporting for period 1 - CosmoChart (Charting the multi-TeV cosmos: long-range interactions in dark matter and baryogenesis)
Période du rapport: 2021-09-01 au 2023-02-28
The project CosmoChart concerns the origin of the cosmological abundance of ordinary matter and dark matter, and the fundamental nature of the latter. Elucidating these issues will not only allow us to understand the evolution and the structure of our universe better, but will also constitute a momentous discovery of new fundamental physics. The overall objectives include building theories for the generation of the ordinary matter-antimatter asymmetry and for dark matter, and examining their theoretical and phenomenological implications, such that these theories can be tested by our experimental probes.
The project is contributing to our understanding of the universe and the most fundamental laws of nature. The importance of this endeavour cannot be overemphasised. The comprehension of the physical world, and the dissemination of the knowledge to the society, liberated our societies from fears and superstitions, enabled us to solve big problems and build prosperous and creative societies. Fundamental research has also more immediate impact. The contributions of the field of high-energy physics to the technological advancement of our entire society are well-known and wide-ranging, from inventing the world wide web, to advancing medical technology. Theoretical research, such as that carried out in this project, is an integral part of the research, and indeed of any discovery in particle physics. It provides the vision and the essential guidance that enable us to design effective experimental strategies which can lead to important discoveries.
1) Developed the formalism for the dark matter decoupling in early universe when metastable dark matter bound states exist in the spectrum of the theory.
2) Investigated the effect of dark matter semi-annihilation with right-handed neutrinos, on the dark matter relic density and indirect detection signals.
3) Derived constraints on the interaction strength between dark matter and electrons, taking into account that the scattering of dark matter particles on electrons in the galaxy can accelerate dark matter particles thus enhancing their recoil in direct detection experiments.
4) Derived exclusion limits on dark matter-neutrino scattering cross-section.
5) Proposed an explanation for an anomaly appearing in flavour experiments (RKstar) in the context of R-partity violating supersymmetry.
6) Proposed an explanation for the excess observed at the dark matter direct detection experiment Xenon1T, using an extended scalar sector.
7) Put forward a scenario where the matter-antimatter asymmetry generation in the early universe leads also to the formation of primordial black holes that contribute to dark matter, and showed that this scenario may have led to the production of gravitational waves in the early universe.
8) Proposed a minimal scenario of electroweak symmetry non-restoration at high temperatures in the early universe.
9) Investigated how angular correlations in nuclear beta decay are important tests of the Standard Model.
10) Employed gamma-ray observations by H.E.S.S. to place constraints on dark matter annihilation.
1) Non-perturbative effects due to long-range interactions in the context of matter-antimatter asymmetry generation.
2) The effect of the Higgs doublet as a light force mediator in the context of dark matter and baryogenesis.
3) Cosmological phase transitions and bound states.
4) Production of gravitational waves in the early universe.