Dark Matter: Origin, Detection, and Collider Implications

Abstract

Cosmological observations have precisely measured the amount of cold dark matter (CDM) in the Universe. The best fit value corresponds to around 23% of the Universe being composed of CDM. Nothing in the Standard Model (SM) is able to account for this cold dark matter. This provides unambiguous evidence for physics beyond the SM. From particle physics, the hierarchy between the electroweak and Planck scales within the SM provides motivation to consider new physics beyond the SM. In this thesis, I investigated the origin of CDM, analyzed various prospects for indirect detection, and studied its collider implications.We focused on two such models: the Left Right Twin Higgs (LRTH) model and the Inert Doublet model (IDM). Both of these models contain a neutral scalar that is stable and a good CDM candidate. We performed a CDM analysis, and identified regions of parameter space that can account for all of the CDM in the Universe.CDM can become trapped around massive objects such as the Sun, Earth, and galactic center. Over time, these CDM particles can annihilate to produce neutrinos and photons. Within the IDM framework, we analyzed the neutrino signal from the Sun and Earth and the photon signal from the galactic center.Due to the nature of new particles within the IDM, there are implications for signals at high energy colliders, such as the Large Hadron Collider (LHC). These particles are produced and can subsequently decay to CDM, jets, and leptons. Within the framework of the IDM, we performed a dilepton signal analysis at the LHC.There exists a synergy between particle physics and cosmology. The study of the interplay between these two fields could provide valuable insights and bring a better understanding of Nature within our grasp. It is an exciting time for physics.