Searching for HI around MHONGOOSE Galaxies via Spectral Stacking

<p>Stacked spectra obtained from spectrally stack around 14 nearby galaxies observed at 1.4 GHz as part of the MHONGOOSE survey (<a href="https://ui.adsabs.harvard.edu/abs/2024A%26A...688A.109D/abstract" target="_blank" rel="noopener">de Blok et al., 2024</a>). The reference paper is available at <a href="https://ui.adsabs.harvard.edu/abs/2024arXiv241111584V/abstract" target="_blank" rel="noopener">NASA-ADS</a>.</p> <p><em>First page:&nbsp;</em>detections in the stacked spectra of the shallow cubes. Each panel shows a single-track stacked spectrum (in blue) and its 9-channel boxcar smoothed version (in red). The detected source is highlighted. The horizontal grey dashed lines are the &plusmn;&sigma; level for the unsmoothed spectrum, while the black dashed line is the 0-flux level. The vertical black dashed-dotted line is, instead, the 0-km/s reference velocity. The galaxy name and the cell size are provided in the bottom-left corner, while at the bottom-right is reported if the detection was also visually identified in its corresponding cube.<br><em>Second page</em>: detections in the stacked spectra of the full-depth cubes. Each panel shows a single-track stacked spectrum (in blue) and its 9-channel boxcar smoothed version (in red). The detected source is highlighted. The horizontal grey dashed lines are the &plusmn;&sigma; level for the unsmoothed spectrum, while the black dashed line is the 0-flux level. The vertical black dashed-dotted line is, instead, the 0-km/s reference velocity. The galaxy name and the cell size are provided in the bottom-left corner, while at the bottom-right is reported if the detection was also visually identified in its corresponding cube.</p>