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: http://www.mrao.cam.ac.uk/~pa/galaxy_evolution/science_ISM.html
Дата изменения: Fri Feb 1 14:53:18 2002 Дата индексирования: Tue Oct 2 07:55:19 2012 Кодировка: Поисковые слова: neptune |
Introduction
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Cavendish AstrophysicsRegulating the ISM and Star FormationIn order to investigate the cosmological evolution of star-forming galaxies it is essential that we understand the physics which controls the evolution and regulation of star formation in the ISM. Therefore one aspect of our work is to investigate these processes, both observationally and theoretically, in galaxies in the local Universe where observational tools are most powerful.The interplay between star formation and the inter-stellar medium is both fundamental to how galaxies evolve with cosmic time and highly complex. It has also become clear, especially since the observation of the "Hubble Deep Field", that typical galaxies have undergone many interactions during their evolution. We use a combined observational and numerical approach to study interacting and merging galaxies in the local Universe. One of the principal results of this work has been to demonstrate the importance of gas-dynamical effects during galaxy-galaxy interactions. Purely tidal forces cannot always explian the gas structures seen around interacting galaxies. An example of this is illustrated below.
Although the very gas-rich nature of systems like NGC 4490/85 system is rather atypical in the local Universe, such systems are likely to be very common in the early Universe. The importance of processes such as described above in the evolution of galaxies remains unquantified but should be included in future models of galaxy evolution. As well as detailed studies of individual systems,
Other related studies currently being made include the study if turblence
in the ISM of our Galaxy. The high resolution of available observations
of atomic hydrogen in our own Galaxy means that it is possible to study,
statistical, the structure in the ISM over a wide
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