Reconstructing reality: Strategies for sideband deconvolution

Abstract

We present a study aimed at optimizing the observing strategy for double-sideband molecular line surveys, in order to achieve, for this kind of data, the best possible single-sideband reconstruction. The work is based on simulations of the acquisition of spectral line surveys with the HIFI instrument on board the Herschel Space Observatory, but our results can be applied to the general case. The reconstruction of the simulated data is obtained through the Maximum Entropy Method. The main factors responsible for degrading the quality of the reconstruction are taken into account: high rms noise in the data, pointing errors (particularly in the presence of intrinsic chemical structure in the source) and sideband imbalances. The presented results will allow the users of the new powerful submillimeter and THz telescopes, such as APEX, ALMA and Herschel, to make the most efficient use of their instruments for line survey work.