Radioactive 26Al in the Galaxy - first results from SPI/INTEGRAL -
The image shows a map of the Galaxy obtained with CGRO-Comptel (1991-2000).
The insets show the clear detection of the 26Al line with the SPI instrument
on-board INTEGRAL after the first months of operation. This gamma-ray line
is a tracer of recent nucleosynthesis, because of the relatively short
lifetime of 26Al; it is formed by the core-collapse of massive stars.
The detection of the lines shows the ability of the SPI instrument to
detect gamma-ray lines even with modest exposures. This opens up exciting
possibility for more detailed studies of this line, since especially the
Galactic Center will be observed by INTEGRAL for much longer (e.g. as part
of the Galactic Center Deep Exposure).
