CERN develops 3D-printed plastic scintillators for neutrino detectors

Neutrinos are perhaps one of the most elusive yet ubiquitous particles around us. Researchers at CERN have invested heavily in detecting these ghastly particles with the T2K experiment, which is a leading neutrino oscillation experiment in Japan.

However, scientists are looking to upgrade the experiment’s detector to yield more precise results. Plastic scintillators are frequently employed in such neutrino oscillation experiments, where they reconstruct the final state of the neutrino interaction. The upgraded detector requires a two-tonne polystyrene-based plastic scintillator detector that is segmented into 1 cm^3 cubes. These small cubes yield precise results but require finer granularity which ultimately makes the detector assembly harder.

With this trade-off in mind, the CERN EP-Neutrino group in collaboration with the Institute for Scintillation Materials (ISMA) of the National Academy of Science of Ukraine developed a new plastic scintillator production technique that involves additive manufacturing. Jargon aside, the solution involves 3D-printing a single gargantuan block of scintillator containing many optically independent cubes.

This would do away with the issue of assembling individual cubes, which could thus be produced in any size, including smaller than 1 cm^3, and relatively quickly (volumes bigger than 20 x 20 x 20 cm^3 can be produced in about a day).

The preliminary test runs of the 3D-printed cube have shown promising results thus far and demonstrate the proof of concept.

The scintillation light yield of a polystyrene-based scintillator 3D-printed with fused deposition modelling has been found to be comparable to that of a traditional scintillator.

However, CERN noted that the complete adoption of these 3D-printed scintillators requires fine-tuning of the 3D-printer configuration and further optimization of the scintillator parameters before the light reflector material for optically isolating the cubes can be developed. Nevertheless, the team noted that the technique is worth exploring. This is due to the fact that 3D-printed plastic scintillators are not only robust and cost-effective but their potential applications extend beyond the domain of high energy physics to fields like cancer therapy where particle detectors are often used.