2002A&A...383.1088W

Ground-based astronomical continuum observations at (sub)millimeter wavelengths are especially difficult, because the emission of the atmospheric water vapor is usually much stronger than any astronomical signal. We present here the principles of the data reduction and first results of a new observing method that accounts for the atmospheric emission by measuring its total power with an array of detectors. We call the method fastscanning. We outline the data reduction for (sub)millimeter bolometer arrays and demonstrate the effectiveness by presenting results of astronomical observations done with the new method.