Zeeman effect

American  

noun

Physics, Optics.

1. the dividing of a spectral line or lines as a result of placing a radiation source in a magnetic field. The division consists of three equally spaced lines normal Zeeman effect in systems for which the spin quantum number is zero, or of three or more unequally spaced lines anomalous Zeeman effect in systems for which the spin quantum number is not zero.

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Zeeman effect British  

/ ˈziːmən /

noun

1. the splitting of a spectral line of a substance into several closely spaced lines when the substance is placed in a magnetic field

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Zeeman effect Scientific  

1. The splitting of single spectral lines of an emission or absorption spectrum of a substance into three or more components when the substance is placed in a magnetic field. The effect occurs when several electron orbitals in the same shell, which normally have the same energy level, have different energies due to their different orientations in the magnetic field. A normal Zeeman effect is observed when a spectral line of an atom splits into three lines under a magnetic field. An anomalous Zeeman effect is observed if the spectral line splits into more than three lines. Astronomers can use the Zeeman effect to measure magnetic fields of stars.

2. Compare Stark effect

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Etymology

Origin of Zeeman effect

First recorded in 1895–1900; named after P. Zeeman

Example Sentences

The magnetic fields can be measured through the Zeeman effect of radiative emissions of atoms and molecules.

From Salon • Apr. 16, 2025

Using the Zeeman effect tracer detected by FAST, astronomers might even be able to measure the magnetic field strength in the accretion disks of gas and dust around newly born stars.

From Science Magazine • Jan. 5, 2022

What it the Zeeman effect and what does it tell us about the Sun?

From Textbooks • Oct. 13, 2016

This is implied by the fact that the Zeeman effect splits spectral lines into several discrete lines.

From Textbooks • Aug. 12, 2015

Even the Zeeman effect, although it may tend to establish the fact that light is produced by vibratory movement, by no means proves that it is propagated in the same manner.

From The Mechanism of Life by Leduc, Stéphane