In 1960 Donald A. Glaser was awarded the 1960 Nobel Prize in Physics. But eight years before he won the Nobel prize, he invented an apparatus (The bubble chamber) His apparatus would give the scientist the leverage to advance studies in Electricity, Emf and radioactivity. Many concepts such as weak neutral currents, electroweak theory and dark matter were brought to light. We could refer to it as an image detector for tracking particles in high-energy.
What Exactly is a Bubble Chamber?
A bubble chamber is an apparatus, designed to track ionizing particles by making them visible as a row of bubbles in a liquid. It consists of a sealed chamber that has to be filled up with some form of liquefied gas, (often liquid hydrogen, xenon, helium or propane). It is constructed in such a manner that the pressure inside reduces quickly; can then detect electrically charged particles as it moves through it. The liquid is originally at a temperature just below its boiling point. When the pressure reduces, the boiling point becomes lower, so that it is less than the temperature of the liquid, leaving the liquid superheated. If charged particle passes through this superheated liquid, it leaves a trail of tiny gas bubbles (illuminated enough, one can capture it in a camera).
Several cameras are mounted around it, allowing a three-dimensional image of an event to be captured. If a magnetic field is present, the tracks of the particles curve. Positively charged particles curving in one direction and negatively charged particles curving in the opposite direction. Factors like mass, speed, and charge of the particle may affect the curve. Also, it detects the neutral particles indirectly.
The bubble chamber is particularly useful for studying high-energy particles that would pass through a cloud chamber too quickly to leave a detailed enough track but which pass more slowly through the bubble chamber because of the greater density of the liquid.
Examples of Bubble Chamber
Even though the operating principle remains the same, the Bubble Chamber comes in different shapes and sizes. But notable among them are –
Uses of Bubble Chamber
The application and use of the bubble chambers are very vast. Talking about particle physics in general, courtesy of the bubble chamber the microworld of physics was un-mystified. (omega-minus meson and hadron resonances, hadron spectrum, SU(3) and constituent quarks, dynamical quarks), weak neutral currents, electroweak theory and dark matter) Emf, radioactivity
Bubble chambers may be similar to cloud chambers, both in the application and in basic principle, however, there are some distinctive differences. While both of them could be used as is a particle detector, A Cloud Chamber detect ionizing particles and determine their trajectories. But it does not show the particles themselves, instead, it shows where they have been. Particles form a condensation trail in the chamber which is visible as a fine mist, and this shows a particle’s path through the chamber
And unlike the cloud chamber Instead of a supersaturated vapour that can condense into a liquid, a bubble chamber uses a liquefied gas that is at such a low pressure that it is on the edge of “boiling” back into a gas.
A blind eye cannot be turned to the usefulness and success of the bubble chambers in the past however, they are not so popular in modern very-high-energy experiments for some reasons:
- Bubble chambers are not big enough to analyze high-energy collisions, where all products and particles should be contained inside the detector.
- In some experiments, the superheated phase must be ready at the exact time collision should take place. This makes detecting short-lived particles complicated.
- Sometimes energy particles may have path radii very large and it hinders precision when estimating the momentum measured especially in a relatively small chamber.
- It can only handle three-dimensional electronic data and the need for photographic readings makes it less convenient, especially in experiments which must be reset, repeated and analyzed many times.
Wire chambers are one of the generally acceptable replacements for the Bubble chambers. It allows particle energies to be measured at the same time. Other replacements include spark chambers, drift chambers, and silicon detectors
Every invention is a discovery or landmark for the new discoveries. The bubble chamber gave a breakthrough in the proper study of particular physics. Even if it is not so much in use anymore we must not forget the quantum leap it provided in its course of service.