Paschen-Back Effect


Paschen-Back effect

An effect on spectral lines obtained when the light source is placed in a very strong magnetic field, first explained by F. Paschen and E. Back in 1921. In such a field the anomalous Zeeman effect, which is obtained with weaker fields, changes over to what is, in a first approximation, the normal Zeeman effect. The term “very strong field” is a relative one, since the field strength required depends on the particular lines being investigated. It must be strong enough to produce a magnetic splitting that is large compared to the separation of the components of the spin-orbit multiplet. See Atomic structure and spectra, Zeeman effect

Paschen-Back Effect

 

the transition of anomalous Zee-man splitting of spectral lines into normal Zeeman splitting under the influence of a strong magnetic field. A strong field here is one that induces Zeeman splitting comparable with or greater than the multiplet splitting of energy levels. In such a field, the splitting pattern becomes simpler—instead of an anomalous pattern, splitting into three components is observed. The Paschen-Back effect was discovered by the German physicists F. Paschen and E. Back in 1912.

Paschen-Back effect

[′päsh·ən ′bäk i‚fekt] (spectroscopy) An effect on spectral lines obtained when the light source is placed in a very strong magnetic field; the anomalous Zeeman effect obtained with weaker fields changes over to what is, in a first approximation, the normal Zeeman effect.