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Reduce pressure before beam arrival; photograph bubbles from several views, then recompress.^[ref]

Unlike the Blackett-Occhialini triggered cloud-chamber experiment, Glaser used counter-controlled flashes after expansion. A detector trigger can select recording in sensitive liquid; subsequent expansion cannot recover a vanished latent track.^[ref]

The diagram deliberately separates the preparation through thermodynamics from the readout decision. Its green interval is a stipulated operating window, not a prediction from pressure alone. Excess superheating can increase unwanted nucleation; insufficient superheating can suppress tracks. A useful proposed sensitivity check holds the readout settings fixed while varying pressure or temperature, with matched background exposures. A proposed timing check moves the beam within the cycle; a proposed optical check varies flash delay to distinguish growing bubbles from changes in spatial resolution. These are experimental design examples, not additional historical measurements.

Awarded to Patrick Maynard Stuart Blackett for developing the cloud chamber method and discoveries in nuclear physics and cosmic ray research. The Blackett-Occhialini triggered cloud-chamber experiment follows one of those methods.^[ref]

A detector trigger decides which candidate events cause a readout or recording. It can concentrate a limited recording capacity on rare interactions, but the accepted events then form a selected sample. A coincidence circuit uses a timing relation between several detectors; the Blackett-Occhialini triggered cloud-chamber experiment made that relation operate an entire camera-and-expansion sequence.