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A technique in which the filter modulation is included in the synthesis of a synthetic-discriminant-function matched spatial filter (SDF MSF) is presented. In the filter synthesis, a system of simultaneous nonlinear equations is solved with an iteration procedure. A computer simulation of the new method using thresholded images of the Space Shuttle over a range of aspect angles was performed for phase-only filters (POFs) and binary-phase-only filters (BPOFs). The filters constructed are capable of obtaining the specified peak-correlation response to within 1% with a high signal-to-clutter-ratio for the one-class problem, the two-class problem, and the multilevel problem. In contrast, conventional projection SDF POFs and BPOFs are unable to produce the desired peak-correlation response.

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The CO J=2-l line has been observed and, in most cases, mapped in 10 star-forming molecular clouds (W3, NGC 1333, NGC 2071, Mon R2, CRL 961, p Oph, W49N, W51A, DR 21, and Cep A). The CO J = 3-2 line has been observed in W3 and DR 21. The CO lines from all of these sources are strongly self-absorbed. By comparing our results with published CO (1-0) line profiles, we find that large corrections to the temperatures of the cloud cores, as measured by the CO (1-0) lines, are required. The corrections for self-absorption bring the CO brightness temperatures into closer agreement with the grain temperatures inferred from far-infrared photometry. The absorbing gas appears to have a variety of geometrical relationships with the absorbed 'background' gas for this group of sources; in one or two cases there may be no physical connection between the absorbed and absorbing regions. For some CO sources, the combined CO data indicate the presence of velocity gradients; however, whether these are due to expansion or collapse cannot be decided on the basis of the presently available data.

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