High-resolution 3D-printed plastic scintillators with tertiary dye

TL;DR

This paper introduces a novel photocurable plastic scintillator with tertiary dye enabling high-resolution 3D printing of complex geometries, maintaining good spectral response and pulse discrimination capabilities.

Contribution

It presents a new scintillator formulation with tertiary dye that significantly improves 3D print resolution while preserving scintillation properties.

Findings

Tertiary dye has minimal impact on emission spectrum and light output.

High-resolution features down to 0.1 mm are achievable with standard 3D printers.

Scintillators show pulse shape discrimination and up to 50% light output of EJ-200.

Abstract

Additive manufacturing offers efficient production of plastic scintillators with nontrivial geometries using vat polymerization, allowing fabrication of geometries which would be difficult or even impossible to produce using conventional subtractive manufacturing. This work presents a novel photocurable scintillator formula that includes coumarin 450 as a tertiary dye to enable high-resolution 3D printing via the manipulation of the 405 nm cure light. Bulk photocured and 3D printed (with and without tertiary dye) samples were compared through observational assessment and spectral response. All samples showed pulse shape discrimination between neutron and gamma events. Inclusion of the tertiary dye has minimal impact on emission spectrum and light output, but significant impact on print resolution as shown by comparison of printed high-complexity geometries and feature resolution test objects. With the use of a cure-limiting dye, unsupported features, such as freestanding pillars, were resolvable down to 0.7 mm. Even finer resolution at or below 0.1 mm was achieved in fully supported, integrated structures printed with off-the-shelf 405 nm desktop 3D printer. Scintillators demonstrated a light output up to 50% of EJ-200 with a PSD figure of merit up to 1.35 at 0.9-1.1 MeVee.