Non-LTE radiative transfer simulations: improved agreement of the double detonation with normal Type Ia supernovae. - Collins, Christine E; Shingles, Luke J; Sim, Stuart A; Callan, Fionntan P; Gronow, Sabrina; Hillebrandt, Wolfgang; Kromer, Markus; Pakmor, Rüdiger; Röpke, Friedrich K (Monthly Notices of the Royal Astronomical Society, 2025)