Right handed neutrinos/heavy neutral leptons are hypothetical particles that are postulated to exist in particle physics. They are the right-handed counterparts of the well-known left-handed neutrinos and belong to a class of particles known as leptons. They are believed to have a large mass and do not interact with ordinary matter except through gravity.
Right handed neutrinos/heavy neutral leptons are important because they may help to explain the origin of the asymmetry between matter and antimatter in the universe. They are also a key component in some theories that aim to unify the fundamental forces of nature.
Right handed neutrinos/heavy neutral leptons are distinguished from left-handed neutrinos by their spin. While left-handed neutrinos have spin 1/2, right-handed neutrinos have spin 0. They also have opposite chirality, meaning they interact differently with other particles.
Right handed neutrinos/heavy neutral leptons have not yet been observed experimentally. However, some indirect evidence for their existence has been found in studies of neutrino oscillations and other phenomena.
Since right handed neutrinos/heavy neutral leptons do not interact with ordinary matter, they are challenging to detect. However, scientists are exploring various methods such as high energy particle collisions and rare decays of other particles to try and detect their presence. Additionally, future experiments, such as the proposed Long-Baseline Neutrino Facility, may be able to provide more insight into the existence of these particles.