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Joined 2026-09-21 Message
Incoming links: Elementary Particles and Bubble Chambers by Donald Arthur Glaser
Bubble-chamber pressure cycle 2026-10-18
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]
Elementary Particles and Bubble Chambers by Donald Arthur Glaser. pp. 537, 541, 550: timing distinction
Bubble-chamber pressure cycle and photographic readout
. Original functional diagram with an arbitrary time coordinate and chosen normalized pressure levels. The dashed equilibrium line assumes fixed temperature; no measured waveform, apparatus scale or historical delay is reproduced. Details.
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.
Glaser bubble-chamber experiment 2026-10-18
Donald Arthur Glaser developed the bubble chamber in 1952 during experimental particle research at Michigan.[ref]
His 1960 lecture, Elementary particles and bubble chambers, describes evacuated capillary bulbs containing pure diethyl ether. Cooling one bulb reduced pressure; the other remained hot. A cobalt-60 source initiated boiling. Small glass chambers subsequently used hot-oil baths, hand-cranked pistons and high-speed photography. Automatic cycling with counter-controlled flashes produced finer tracks. Local ionization deposits energy that can initiate bubble nucleation.[ref]
Later metal-chamber photographs compared operation with and without a nearby radioactive source: wall boiling occurred without interior tracks; irradiation produced tracks before disruptive flow ended sensitivity.[ref]
Elementary Particles and Bubble Chambers by Donald Arthur Glaser. pp. 539–543, Fig. 6
These observations separate two questions: can radiation start boiling, and can a detector preserve the geometry of a passing charged particle? Whole-vessel boiling alone answers only the first. Wall background, finite sensitivity and growth before photography constrain the second.