this proposal is a crucial part of an on-going program to investigate in a self-consistent way the morphological and spectrophotometric evolution of ring galaxies. ring galaxies represent the consequence of a close interaction between a spiral disk and an intruder, triggering a burst of star formation. the result, depending on the parameters of the impact, is a more or less sharp ring surrounding an off-centered nucleus or an empty region. substantial advances have been made in the last two decades in understanding the complex dynamics of galaxy interactions, largely as a result of the efforts of numerical experiments. as suggested by our n-body numerical simulations, the passage of an intruder through a stellar disk generates a transient ring-shaped mass distribution produced by a single density wave propagating through the disk. (curir and filippi, 1994) the efficiency of tidal interactions and merging between galaxies in triggering star formation is also well known since a large fraction of powerful fir emitters are interacting galaxies. ring galaxies are strong fir sources, some of them also brighter than the prototype starburst galaxy m82. as suggested by previous works on this subject (mazzei et al. 1992, mazzei et al. 1994, mazzei and dezotti, 1994) looking at suitable ir spectral ranges we can recover the current value as well as the past trend of the star formation rate. the observational part of this study on ring galaxies so far consist in optical multiband (bvri) ccd images of a sample of objects (bonoli, 1987). together with available iras data, iso observations will provide a unique clue to further investigate the effects of star formation episodes in the mir and fir.
Instrument
CAM01 , PHT03 , PHT22
Temporal Coverage
1996-06-17T12:12:54Z/1997-10-28T08:55:00Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the world's first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
