In astronomy, the Kraft break refers to the abrupt decrease in stars' average rotation rates at surface temperatures below about 6200 kelvin. The so-called break bears the name of astronomer Robert Kraft,[1] though its existence was recognized prior to his publications on the topic.[2] The break is understood to separate stars with deep convective envelopes and efficient magnetic dynamos from those without. The dynamos are thought to maintain magnetic fields that transfer angular momentum to the stellar wind, thus slowing down the star's surface through magnetic braking. In hot stars the process is less efficient (because the convective envelopes are shallow) so the stars continue to rotate quickly.[3]
References
[edit]- ^ Kraft, R. P. (1967), "Studies of Stellar Rotation. V. The Dependence of Rotation on Age among Solar-Type Stars", Astrophysical Journal, 150: 551, Bibcode:1967ApJ...150..551K, doi:10.1086/149359
- ^ Schatzman, E. (1962), "A theory of the role of magnetic activity during star formation", Annales d'Astrophysique, 25: 18, Bibcode:1962AnAp...25...18S
- ^ Maeder, A. (2009), Physics, Formation and Evolution of Rotating Stars (PDF), Astronomy and Astrophysics Library, Bibcode:2009pfer.book.....M, doi:10.1007/978-3-540-76949-1, ISBN 978-3-540-76948-4
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction