IR PHOTOMETRY OF K STARS WITH IR EXCESS openParPART 2closePar THE NATURE OF CIRCUMSTELLAR DUST IN K GIANTS

we propose to obtain deep photometry at 60, 90 and 160 microns of a carefully selected sample of k giants with 60 micron excess in order to determine the nature of the dust emission found in these objects. in particular we wish to investigate the possibility that the infrared excess is due to debris dust, left over from the process of planet formation, which has been reactivated as the star leaves the main sequence and evolves to the red giant phase. if this interpretation is correct, it would imply that stars can retain a cold dust shell throughout their main sequence life, and would show that the vega phenomenon may remain active throughout the life of low and intermediate mass main sequence stars. the proposed observations can only be obtained with iso, since we request observations at wavelengths and with a sensitivity that cannot be achieved with any other instrument available at present or in the near future. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]