Calcium triplet

The infrared Ca II triplet, commonly known as the calcium triplet, is a triplet of three ionised calcium spectral lines at the wavelengths of 8498 Å, 8542 Å and 8662 Å (measured in air). The triplet has a strong emission,^[1] and is most prominently observed in the absorption of spectral type G, K and M stars.^[2][3][4]

See also

• Fraunhofer lines
• Infrared spectroscopy

References

1. Polidan, R. S. (1976). "On the Detection of Binary be Stars" (PDF). Be and Shell Stars: IAU Symposium No. 70. 70: 405. Bibcode:1976IAUS...70..401P.
2. Andretta; Busà; Gomez; Terranegra (2005). "The Ca II Infrared Triplet as a stellar activity diagnostic" (PDF). Astronomy & Astrophysics. p. 669.
3. Jonathan Tennyson (2005). "Astronomical Spectroscopy. An introduction to the atomic and molecular physics in astronomical spectra" (PDF). Imperial College Press. p. 94. Archived from the original (PDF) on 2016-01-16. Retrieved 2016-07-09.
4. G. Kordopatis, A. Recio-Blanco, P. de Laverny, A. Bijaoui, V. Hill, G. Gilmore, R. F. G. Wyse and C. Ordenovic (2011). "Automatic stellar spectra parameterisation in the IR Ca ii triplet region" (PDF). Astronomy & Astrophysics. p. 535, A106. Archived from the original on 2011-11-21.{{cite web}}: CS1 maint: multiple names: authors list (link)