-gz- noun
Usage: usually capitalized B
Etymology: after W.H. & W.L. Bragg
: a law in physics: there is a definite relationship between the angle at which a beam of X rays must fall on the parallel planes of atoms in a crystal in order that there be strong reflection, the wavelength of the X rays, and the distance between the crystal planes : sin Θ = nλ / 2d where Θ is the angle between the incident or the reflected beam and the crystal plane, λ is the X-ray wavelength, d is the crystal plane separation, and n is any integer