SWS Post-Helium Operations: A survey of Stellar Spectra.


The end of the ISO operations is soon coming, but for the SWS there is life after helium exhaustion! Once helium exhaustion has been announced a period of testing the satellite control systems begins (the Test & Technology Phase, TTP), lasting approximately four weeks. Because it is probable the SWS band 1 (2.4 to 4 micron) InSb detectors will operate at the elevated temperatures expected during this period, the ISO Science Team (IST) has approved an observing programme to make use of any vacant timeslots in the TTP schedule. It is expected about 150 hours observing time will be made available this way. Test observations using band 1 will go ahead straight after helium exhaustion and, if successful, the programme will then begin.

The observing programme aimes at obtaining 2.4-4 micron scans at the full grating resolution of all stars in the MK spectral classification scheme, i.e. to extend this classification scheme to the infrared. In addition, stars with cool dust shells, having an IRAS LRS classification, will be added. These data will be very useful in constructing templates for infrared spectra of unresolved clusters of stars, for population synthesis work. The data will become public domain as soon as data reduction is at a satisfactory level. An atlas of stellar spectra will also be published.

For more information, please contact:

Rens Waters