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Zeeman effect

The Zeeman effect (/ˈzeɪmən/; Dutch pronunciation: ), named after the Dutch physicist Pieter Zeeman, is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden (in the dipole approximation), as governed by the selection rules.( n = 2 , l = 1 {displaystyle n=2,l=1} )( n = 1 , l = 0 {displaystyle n=1,l=0} )( n = 2 , l = 1 {displaystyle n=2,l=1} )( n = 1 , l = 0 {displaystyle n=1,l=0} ) The Zeeman effect (/ˈzeɪmən/; Dutch pronunciation: ), named after the Dutch physicist Pieter Zeeman, is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden (in the dipole approximation), as governed by the selection rules. Since the distance between the Zeeman sub-levels is a function of magnetic field strength, this effect can be used to measure magnetic field strength, e.g. that of the Sun and other stars or in laboratory plasmas.The Zeeman effect is very important in applications such as nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, magnetic resonance imaging (MRI) and Mössbauer spectroscopy. It may also be utilized to improve accuracy in atomic absorption spectroscopy.A theory about the magnetic sense of birds assumes that a protein in the retina is changed due to the Zeeman effect. When the spectral lines are absorption lines, the effect is called inverse Zeeman effect. Historically, one distinguishes between the normal and an anomalous Zeeman effect (discovered by Thomas Preston in Dublin, Ireland). The anomalous effect appears on transitions where the net spin of the electrons is an odd half-integer, so that the number of Zeeman sub-levels is even. It was called 'anomalous' because the electron spin had not yet been discovered, and so there was no good explanation for it at the time that Zeeman observed the effect. At higher magnetic field strength the effect ceases to be linear. At even-higher field strength, when the strength of the external field is comparable to the strength of the atom's internal field, electron coupling is disturbed and the spectral lines rearrange. This is called the Paschen-Back effect.

[ "Magnetic field", "Zeeman slower", "Calcium monohydride", "Zeeman energy" ]
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