Data and code for "Three overlooked error sources in terahertz time-domain spectroscopy of polymer compacts"

Processed terahertz time-domain spectroscopy data and analysis code for a study of three overlooked error sources in THz-TDS of cold-pressed polymer compacts: disc porosity, mounting reproducibility, and the number of replicates required for a target sensitivity. Contents: log10|T| spectra for 1840 individual scans grouped into 74 independent mountings across six cold-pressed discs (PEEK, PES, PPO, PTFE), covering the 0.40-2.50 THz band; per-mounting metadata (mass, diameter, thickness, optical thickness); summary statistics including per-disc mounting reproducibility and porosity; and all Python scripts needed to recompute every number and figure in the paper. Raw instrument files (9.2 GB) are available from the corresponding author on reasonable request.