Structure of C9 through proton resonance scattering with the Texas Active Target detector

Structure of very exotic nucleus, carbon-9, has been studied using novel detector - Texas Active Target (TexAT). Carbon-9 can be produced by removing three neutrons from the stable carbon-12 isotope, which we inhale every few seconds as part of carbon-dioxide gas. The structure of this exotic carbon, carbon-9, is very different from the stable carbon (carbon-12) and much less explored due to experimental difficulties of producing it. Yet, it is important for benchmarking the contemporary, state-of-the-art theories of nuclear structure. In particular, excitation energy of the positive parity states, that indicate an onset of the sd-shell, was not known in 9C. Here, we have conclusively identified the first positive parity state in 9C. It was made possible by the new capabilities provided buy TexAT.