Hanbury Brown–Twiss effect

The Hanbury Brown–Twiss effect is used in intensity interferometry in which correlations of the intensity of light from a star are studied using two detectors. It was first used to determine the diameters of stars and is also used in atomic and nuclear physics.

It was named after Robert Hanbury Brown and Richard Twiss who used it in 1956 to study the star Sirius.

Link to the HBT effect.