arXiv subjects

David McClain

Publications and source records attributed to David McClain.

4 recordsLinked to original sources

arXiv2026

Medical Radioisotopes: Clinical Demand, Production Physics, and Untapped Pathways

Over 40 radioisotopes are currently in use or under development across virtually all fields of modern medicine. Their availability relies on a complex interplay of nuclear physics, radiochemistry, and nuclear medicine. This review provides an isotope-by-isotope map of medically important radioisotopes from the perspective of these disparate yet complementary fields. We address the landscape grouped into three tiers: the established clinical core, including, familiar workhorses such as Tc-99m, F-18, Lu-177; an under-leveraged middle tier including Re-186, Re-188, and Sm-153, and the emerging frontier, radioisotopes with demonstrated but underutilised clinical promise such as Ac-225, At-211, Cu-67, and Sc-47. We discuss the properties of these radioisotopes with respect to clinical applications and their production pathways, as well as the associated nuclear and radiochemical challenges. We synthesise these disparate perspectives to identify situations in which alleviating production-side bottlenecks may improve access and patient outcomes.

physics.med-ph↗

arXiv2026

Medical Radioisotopes: Supply-chain Resilience, Distributed Production, and Access

Over 50 million diagnostic procedures involving medical radioisotopes are performed per year and the number of therapeutic and theranostic agents continues to climb. Yet, the global supply chain is far from stable and many regions are underserved. This is the second of a Series of two review papers providing a comprehensive overview of the landscape of medically relevant radioisotopes. This paper focuses on the supply chain. It presents a critical overview of the 2025-2026 status quo, case studies of acute stressors and disruptions they caused, and methods in place to secure a stable supply. A literature-based analysis is paired with expert interviews. We argue that the ageing fleet of nuclear reactors currently used for the centralised production of many isotopes should be complemented by regional accelerator-based centres, alleviating single-point failures and cross-border logistics complications, and increasing access to short-lived isotopes in harder-to-reach regions and low- and middle-income countries.

physics.med-ph↗

arXiv2026

From Beam to Bedside: Reinforcing Domestic Supply of $^{99}$Mo/$^{99m}$Tc using Novel High-Current D+ Cyclotrons for Compact Neutron Generation and $^{99}$Mo Production

Technetium-99m ($^{99m}$Tc) is essential to more than 16 million diagnostic procedures performed annually in the United States. It is typically acquired on-site from generators containing $^{99}$Mo, in turn produced at nuclear reactor facilities. This supply chain involves multiple points of vulnerability, which can lead to shortages and delays with potentially negative patient outcomes. We report on the development of a new family of cyclotrons originally designed for the IsoDAR neutrino experiment, capable of operating at much higher current than typical cyclotrons. When operated with deuterons at 1.5 MeV/amu and an anticipated continuous beam current of 5 mA, simulations project that such a system would yield $\sim$10$^{13}$ neutrons per second using a thin beryllium target. This neutron yield is sufficient, in principle, to support $^{99}$Mo production without the use of highly enriched uranium or reliance on foreign reactors. Simulations and conceptual design studies suggest that the system's beam dynamics could make it a viable pathway toward decentralized, hospital-based isotope generation. The relatively low energy of the deuterons minimizes activation and safety concerns. This work presents the physics motivation, technical design considerations, and projected neutron yields, outlining a pathway from a neutrino-physics prototype to a biomedical isotope production platform.

physics.acc-ph↗

arXiv2020

Plastic Scintillation Detectors for Time-of-Flight Mass Measurements

Fast timing detectors are an essential element in the experimental setup for time-of-flight (ToF) mass measurements of unstable nuclei. We have upgraded the scintillator detectors used in experiments at the National Superconducting Cyclotron Laboratory (NSCL) by increasing the number of photomultiplier tubes that read out their light signals to four per detector, and characterized them in a test experiment with $^{48}$Ca beam at the NSCL. The new detectors achieved a time resolution ($σ$) of 7.5 ps. We systematically investigated different factors that affect their timing performance. In addition, we evaluated the ability of positioning the hitting points on the scintillator using the timing information and obtained a resolution ($σ$) below 1 mm for well-defined beam spots.

physics.ins-det↗