Physicists at Vilnius University have developed a sensor capable of detecting and localizing radiation sources with a level of precision that surpasses currently available instruments. The device does not simply measure the presence of radioactivity: it can pinpoint its location — a capability that opens concrete possibilities for nuclear power plant monitoring and high-energy physics research.
The sensor is designed to operate in demanding environments. Intended applications include radioactivity monitoring in laboratories conducting high-energy particle experiments and continuous surveillance of nuclear facilities. The ability to localize a source — rather than merely detect it — is what sets this device apart from most existing instruments, which return scalar readings with no directional information. Knowing where a source is located fundamentally changes what operators can do in the field.
This development comes amid growing demand for more precise and compact measurement tools. Conventional directional detection sensors typically require arrays of at least one hundred elements arranged in a 10×10 configuration — structures that are costly and difficult to install. The international research community is pushing to drastically reduce hardware complexity, compensating with advanced computational processing. A team from MIT and Lawrence Berkeley National Laboratory demonstrated, in a paper published in Nature Communications, that just four pixels arranged in Tetris-inspired shapes, combined with a neural network trained on Monte Carlo simulations, can deliver high-resolution directional predictions. The Lithuanian sensor follows a similar logic: fewer physical components, greater intelligence in signal analysis.
On the hardware side, parallel progress has been made. The University of Maine has developed microelectronic sensors just 100 nanometers thick — roughly one-thousandth the width of a human hair — with platinum-alloy electrodes, tested at the Ohio State University Nuclear Reactor Laboratory. All seven prototypes operated without degradation after five days of exposure at the reactor’s maximum power output, at temperatures around 800 degrees Celsius. Sensors that can survive inside an operating reactor core deliver real-time data that is simply not obtainable by any other current means.
Vilnius University is active on multiple fronts in nuclear and particle physics. Its Center for Experimental Nuclear and Particle Physics has recently received official CERN approval to participate in the assembly and testing of modules for the CMS detector upgrade, as part of the High-Luminosity Large Hadron Collider program. CMS inner tracker representatives evaluated the group’s work on July 1, 2026, approving both its procedures and available equipment. The Lithuanian team is the only group in the country involved in this phase of the CMS tracker endcap pixel module upgrade.
The convergence of miniaturization, reconstruction algorithms, and materials capable of withstanding extreme environments defines the current trajectory of nuclear instrumentation. A sensor that detects and localizes with precision — and does so without the bulky infrastructure of previous systems — is a tool that can be deployed at far greater scale: across power plants, physics laboratories, and continuous environmental monitoring networks. The denser the measurement network, the faster and more reliable the response to any anomalous behavior at a facility.
