ISO Status Report - February 2004
Systematic data reduction projects of ISO spectroscopic modes have been completed and the products are being ingested in the archive. Detailed requirements for the observations. data quality reports have been consolidated, for the next major release of the IDA, planned for spring 2004. The IDA continues to be heavily used, with about 60 users downloading every month typically the equivalent of 5-10% of its scientific observations content.
The legacy version of the ISO Handbook (5 volumes, 1200 pages) has been released on the Web and is being distributed in hardcopy to all PIs of ISO observing proposals as well as to some 300 libraries worldwide.
Science Highlights
ISO continues to have a significant presence in the refereed literature. ISO papers cover all areas of astronomy. Recent results include:
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The first detection of far-infrared emission associated with an extended HI disk.
Spiral galaxies in the local universe are commonly observed to be embedded in extended disks of neutral hydrogen - the so-called .extended HI disks.. Based on observations made with the ISOPHOT instrument, the first detection of cold dust in the extended HI disk of a spiral galaxy has been reported. This detection was achieved through a dedicated deep far-infrared observation of a large field encompassing the entire HI disk of the edge-on spiral galaxy NGC891. The discovery indicates that the extended HI disk of NGC 891 is not primordial in origin.
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New evolutionary synthesis models of M82 based on ISO spectroscopy.
The global starburst activity in M82 appears to have occurred in two successive episodes each lasting a few million years. The first episode took place throughout the central regions of M82 and was particularly intense at the nucleus, while the second episode occurred predominantly in a circumnuclear ring and along the stellar bar. This sequence is interpreted as resulting from the gravitational interaction between M82 and its neighbour M81, and subsequent bar-driven evolution. The short burst duration on all spatial scales indicates strong negative feedback effects of starburst activity, both locally and globally.