Work

Dose-dependent refractive index changes in megavoltage x-ray-irradiated high-density polyethylene measured by terahertz time-domain spectroscopy

Year: 2026

Type: article

Abstract: This note investigates terahertz time-domain spectroscopy (THz-TDS) as a non-destructive technique for detecting radiation-induced changes in high-density polyethylene (HDPE). HDPE samples were irradiated with megavoltage x-rays at doses from 100 Gy to 800 Gy using a medical linear accelerator at a dose rate of 6.00 Gy min −1 . The refractive index, measured with THz-TDS in the range 0.3–2.5 THz, showed an overall positive linear association with absorbed dose ( R 2 = 0.83), corresponding to a sensitivity of 7 × 10 −6 Gy −1 with a 95% confidence interval of 4.10–9.84 × 10 −6 Gy −1 . The absorption coefficient shows no systematic dependence on dose within the measurement uncertainty. These results provide preliminary evidence that THz-TDS can detect dose-dependent changes in the refractive index of HDPE and may provide a basis for further investigation of polymer-based dosimetry.

Source: Biomedical Physics & Engineering Express

DOI: 10.1088/2057-1976/ae9e38

Authors: Katrine Gerassimovitch Eskildsen, Esben Pilgaard Skovsen, Mads Høyrup Brincker

Institutions: Aalborg University, Aalborg University Hospital

Language: English

Topic: Terahertz technology and applications

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $2,400