H-alpha
Also known as hydrogen alpha, Hα, Balmer alpha line, Balmer line, alpha line
thumb|In the Bohr model of the hydrogen atom, the electron transition from energy level n = 3 to n = 2 results in the emission of an H-alpha photon.
Article
5 sectionsContents
- Balmer series
- Filter
- See also
- References
- External links
thumb|In the Bohr model of the hydrogen atom, the electron transition from energy level n = 3 to n = 2 results in the emission of an H-alpha photon.
Hydrogen-alpha, typically shortened to H-alpha or Hα, is a deep-red visible spectral line of the hydrogen atom with a wavelength of 656.28 nm in air and 656.46 nm in vacuum. It is the first spectral line in the Balmer series and is emitted when an electron falls from a hydrogen atom's third- to second-lowest energy level. H-alpha has applications in astronomy where its emission can be observed from emission nebulae and from features in the Sun's atmosphere, including solar prominences and the chromosphere.