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In this paper we introduce a method for stacking data cubelets extracted from interferometric surveys of galaxies in the redshifted 21-cm H,textsc{i} line. Unlike the traditional spectral stacking technique, which stacks one-dimensional spectra extracted from data cubes, we examine a method based on image domain stacks which makes deconvolution possible. To test the validity of this assumption, we mock a sample of 3622 equatorial galaxies extracted from the GAMA survey, recently imaged as part of a DINGO-VLA project. We first examine the accuracy of the method using a noise-free simulation and note that the stacked image and flux estimation are dramatically improved compared to traditional stacking. The extracted H,textsc{i} mass from the deconvolved image agrees with the average input mass to within 3%. However, with traditional spectral stacking, the derived H,textsc{i} is incorrect by greater than a factor of 2. For a more realistic case of a stack with finite S/N, we also produced 20 different noise realisations to closely mimic the properties of the DINGO-VLA interferometric survey. We recovered the predicted average H,textsc{i} mass to within $sim$4%. Compared with traditional spectral stacking, this technique extends the range of science applications where stacking can be used, and is especially useful for characterizing the emission from extended sources with interferometers.
H I stacking has proven to be a highly effective tool to statistically analyse average H I properties for samples of galaxies which may or may not be directly detected. With the plethora of H I data expected from the various upcoming H I surveys with
Motivated by the discovery of large-scale ionized clouds around AGN host galaxies, and particularly the large fraction of those which are consistent with photoionized gaseous tidal debris, we have searched for [O III] emission over wide fields around
We present the detection of multiple CO line transitions with ALMA in a few tens of infrared-selected galaxies on and above the main sequence at z=1.1-1.7. We reliably detected the emission of CO(5-4), CO(2-1), and CO(7-6)+[CI](2-1) in 50, 33, and 13
We demonstrate the redshift-evolution of the spectral profile of H i Lyman-alpha (Ly{alpha}) emission from star-forming galaxies. In this first study we pay special attention to the contribution of blueshifted emission. At redshift z = 2.9-6.6, we co
Galaxies occupy different regions of the [OIII]$lambda5007$/H$beta$-versus-[NII]$lambda6584$/H$alpha$ emission-line ratio diagram in the distant and local Universe. We investigate the origin of this intriguing result by modelling self-consistently, f