Source inversion of both long- and short-lived radionuclide releases from the Fukushima Daiichi nuclear accident using on-site gamma dose rates.

•Source inversion of 23 radionuclides using overlooked on-site gamma dose rates.•Inversion model for incorporating conflicting priors of different mechanisms.•Source term estimate that combines the advantages of different priors.•Validation by both on-site gamma dose rates and regional-scale measurements.•Model prediction comparison for source terms obtained through different mechanisms.