Grant: Subatomic Physics Envelope - Project

The TRIUMF Ultra-Cold Advanced Neutron (TUCAN) collaboration is being commissioned with major Canadian contributions supported by SAP Project Grant SAPPJ-2023-00029 (PI Prof. Jeff Martin). As a new TUCAN collaborator, this bridging grant will support my research program that provides urgent and sustained support to prepare and operate TUCAN's neutron detector system. TUCAN targets an order-of-magnitude improvement in the precision of the neutron electric dipole moment (nEDM) in this decade. This powerful test of nature's fundamental symmetries will have unprecedented sensitivity to new physics sources of Charge Parity (CP) violation that could address open questions including the matter-antimatter asymmetry of the universe and the strong CP problem. TUCAN will employ a unique spallation-drive superfluid helium source technology to achieve an ultra-cold neutron (UCN) density two orders-of-magnitude larger than current state-of-the-art experiments. This source will come online in -2024. TUCAN requires four UCN detectors to conduct its nEDM measurement. TUCAN's initial UCN detector design however has met a serious external roadblock, stalling the readiness of this system. The research program I propose will build, and lead long-term operations of, a new cost-effective scintillating gas UCN detector design, which is much simpler to manufacture. Its feasibility for efficient UCN detection was recently proven by our competitors at PSI. In summer 2023 significant progress was achieved by a U. Manitoba summer student and MITACs GRI under my supervision as we successfully built a scintillating gas detector. The requested funds will be used to install and operate this detector at TRIUMF, and prepare three additional units. This research program is essential to facilitate TUCAN's precision target and timeline.  I will apply my expertise in scintillator detectors and my experience coordinating Photon and Neutron Performance for the Belle II collaboration to accomplish this synergistic contribution to the Canadian group activities. The funds requested will establish my research team consisting of a PhD, MSc, and undergraduate summer students, and will be used to purchase some specialized hardware for the scintillating gas detectors. The MSc student will lead the installation and operation of our existing scintillating gas detector and use it to observe the unprecedented UCN density produced by the newly upgraded source. The PhD student will build the remaining detectors and be responsible for long-term detector operations as the nEDM experiment runs commence in 2025.  The project features invaluable opportunities for the training of highly qualified personnel (HQP) by encompassing a range of skillsets including hands-on detector hardware work, GEANT4 simulation, and data analysis. The timeline is urgent to ensure nEDM data-taking starts in 2025 and is ideal for HQP to establish themselves in important leadership roles within the collaboration.