Balmer-alpha line

spectroscopy

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June 17, 2026

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The Balmer-alpha line, also known as H-alpha, is a specific spectral line within the Balmer series of hydrogen. Spectral lines are produced when a photon changes the energy state of an ion, atom, or molecule. In the case of the Balmer series, these lines are observed when an electron in a hydrogen atom transitions from a higher energy state to the second energy level (n=2).12

The H-alpha line specifically occurs when an electron moves from the n=3 energy state to the n=2 state. This transition emits a photon with a wavelength of 656.21 nanometers, which falls within the red region of the visible spectrum. The mathematical relationship for the wavelengths of the Balmer series was discovered by Johann Balmer and later generalized by Johannes Rydberg. These spectral lines are crucial for understanding atomic structure and have been observed in the Sun's spectrum as Fraunhofer lines.123

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Stark effect
…the characteristic spectral lines, called Balmer lines, of hydrogen were split into a number of symmetrically spaced components, some of which were linearly polarized (vibrating in one plane) with the electric vector parallel to the lines of force, the remainder being polarized perpendicular to the direction of the field except…
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…the characteristic spectral lines, called Balmer lines, of hydrogen were split into a number of symmetrically spaced components, some of which were linearly polarized (vibrating in one plane) with the electric vector parallel to the lines of force, the remainder being polarized perpendicular to the direction of the field except…
Read More