Interferometric cubelet stacking to recover H <scp>i</scp> emission from distant galaxies

ABSTRACT In this paper, we introduce a method for stacking data cubelets extracted from interferometric surveys of galaxies in the redshifted 21-cm H},i line. Unlike traditional spectral technique, which stacks one-dimensional spectra cubes, examine based on image domain that makes deconvolution possible. To test validity assumption, mock sample 3622 equatorial GAMA survey, recently imaged as part DINGO-VLA project. We first accuracy using noise-free simulation and note stacked flux estimation are dramatically improved compared to stacking. The H i mass deconvolved agrees with average input within 3 per cent. However, stacking, derived is incorrect by greater than factor 2. For more realistic case stack finite S/N, also produced 20 different noise realizations closely mimic properties survey. recovered predicted ?4 Compared technique extends range science applications where can be used, especially useful characterizing emission extended sources interferometers.