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: http://star.arm.ac.uk/annrep/annrep2004/node58.html
Дата изменения: Tue Apr 19 13:35:58 2005 Дата индексирования: Tue Oct 2 04:49:34 2012 Кодировка: Поисковые слова: jet |
By contrast, stars of low mass like our Sun are formed within molecular clumps. Michael Smith has been investigating the clumps and the individual cores they contain within one nearby cloud near the star Rho Ophiuchi. With Stanke (Hawaii), Khanzadyan (Heidelberg) and Gredel (Calar Alto), he has determined the masses of over 100 protostellar cores and compared this to the distribution of masses for stars. The distributions are very similar, suggesting that stars form directly from the cores. Furthermore, the mass distribution of cores does not vary with location within the cloud, suggesting a universality which is difficult to explain with current theories. The region has also been investigated in the near-infrared, where numerous new outflows from protostars have been discovered. The results were presented at a workshop on low mass stars in Volterra, Italy. The group has also been awarded time with the 10m Keck telescope to try to catch a clump in the process of transforming from atomic into molecular gas.
Michael Smith has continued his work on the Unification Scheme for protostellar evolution. Led by Dirk Froebrich (DIAS, Dublin), the group has combined the computer simulations of Ralf Klessen and Stefan Schmeja (Potsdam) with the Unification Scheme to predict how protostars could evolve given the statistical nature of the mass accretion predicted by the simulations. To compare these results with observations required the development of new statistical techniques to compare different samples. The agreement turned out to be rather weak, probably due to the present paucity of reliable observations.