A technetium star is a star in the spectrum of which there are absorption lines of technetium Tc I (423.8 and 426.2 nm). Such stars were first discovered by Merill in 1952.
Technetium stars belong to the spectral classes M, MS, S, SC, CN. They are located on the asymptotic branch of giants and are similar to red giants , but have a slightly higher luminosity due to the “burning” of hydrogen in the inner shells.
The presence in the spectra of stars of such a short-lived element as technetium proves that heavy elements are formed in stars by nuclear fusion, and are not the result of extraneous pollution.
Content
Examples
Some technetium stars (the spectral class is indicated in parentheses): [1]
- T Cet (M5-6S)
- R And (S5-7)
- U Cas (S5 / 3)
- W And (S7 / 1)
- T Cam (S6 / 5)
- ο 1 Ori (M3S)
- TV Aur (S5 / 6)
- NO Aur (M2S)
- R Gem (S5 / 5)
See also
- Barium star
- Carbon star
- Mercury-Manganese Star
- S type star
Notes
- ↑ Groenewegen, MAT, On the Infrared Properties of S-Stars with and Without Technetium // Astronomy and Astrophysics, Vol. 271, NO. 1 / APRI, P. 180, 1993
Links
- School Astronomy (inaccessible link)
- Technetium Star on The Internet encyclopedia of science , Worlds of David Darling
- Fred Sanner, Observations of technetium stars // Astrophysical Journal, Part 1, vol. 219, Jan. 15, 1978, p. 538-542. (eng.)