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Heavy ion tracks in Ilford K-2 emulsion are simulated with a computer program that makes use of the delta-ray theory of track structure, and the special assumption that the response of the emulsion to gamma-rays is 8-or-more hit. The Ilford K-series of nuclear emulsions is produced from a parent stock called K.0 emulsion, sensitized to become K.1 to K.5, and desensitized to become K–1 to K–3. Our simulations demonstrate that the emulsions K.5 through K.0 to K-1 are 1-or-more hit detectors, while K-2 is an 8-or-more hit detector. We have no data for K-3 emulsion. It would appear that emulsions of intermediate hittedness might be produced by an intermediate desensitization, to mimic or match the RBE-LET variations of biological cells, perhaps to produce a “rem-dosimeter.” In the K-2 emulsion no developable grains are produced by stopping H, He, and Li ions. The emulsion has “threshold-like” properties, resembling etchable track detectors. It should prove useful in the measurement of high LET dose in a strong low LET background, as for pions or neutrons. Since it can be expected to accumulate and repair “sub-lethal damage,” to display the ion-kill and gamma-kill inactivation modes, the grain-count and track width regimes, it may serve to model biological effects.