The HI Content of Red Geyser Galaxies

Red geysers are a specific type of quiescent galaxy, denoted by twin jets emerging from their galactic centers. These bisymmetric jets inject energy and heat into the surrounding material, effectively suppressing star formation by stabilizing cool gas. Building on the work done by Cheung et al. (2016) and Roy et al. (2018) to confirm the presence and evolutionary consequences of these jets, this work exhibits HI gas-to-stellar mass (G/S) spectra contracting through the scaling, stacking, and conversion of 21-cm HI flux data sourced from the HI-MaNGA survey (an extension of the SDSS IV project titled Mapping Nearby Galaxies at Apache Point Observatory (MaNGA)). Our samples were dominated by non-detections, or galaxies with weak HI signals, and consequently by upper limits. By employing a stacking technique that successfully resolved an high SNR emission feature in the red geyser G/S spectrum and allowed for the calculation of a G/S upper limit for the control sample, I estimated an average HI-to-stellar mass ratio (G/S) of 0.176 ± 0.011 for the red geyser sample and a G/S upper limit of 0.027 for the control sample. This result supplies further evidence for the suppression of star formation by red geyser jet activity by demonstrating the ample presence of cold gas in red geyser galaxies.