Detection of alpha particles with undoped poly (ethylene naphthalate)

•PEN is characterised as a scintillation material for alpha particles.•The effective refractive index for PEN is 1.70 in its emission spectrum.•The response to 5486 (6118) keV alpha particles was 554±45 (618±45) keVee.•The energy resolution for 5486 (6118) keV alpha particles was 11.2±0.1 (8.8±0.1) %.•This work will stimulate future use of PEN for radiation detection.

There has been recent interest in the use of undoped, aromatic-ring polymers as organic scintillation materials for radiation detectors. Here, we characterise the response of poly (ethylene naphthalate) (PEN) to alpha particles. The energy response to 5486 keV alpha particles emitted from 241Am was 554±45 keV electron equivalents (keVee), with an energy resolution of 11.2±0.1%. The energy response to 6118 keV alpha particles emitted from 252Cf was 618±45 keVee, with a resolution of 8.8±0.1%. It is also important to characterise the refractive index because it determines how efficiently light propagates in scintillation materials to the photodetector. By taking into account the PEN emission spectrum, it was revealed that its effective refractive index was 1.70. Overall, the results indicate that PEN has potential as a scintillation material for the detection of alpha particles.