Mixing state of aerosol particles at Mt. Hotaka, Japan: A case study in winter

► In this study we investigate the relative abundance and mixing state of individual fine particles. ► Particles collected on Mt. Hotaka, Japan in winter are examined with an EDX analyzer. ► We find that sulfur-potassium particles probably originate from biomass burning. ► We examine the electron-beam sensitivity to fine-ultrafine particles. ► Sensitive/insensitive particles would be sulfur-containing/soot or mineral particles.