• Smith, Nicholas
• Battipaglia, Michael
• Mcallan, Elizabeth
• Schwarz, Gregory
• Singer, Quinton
• Fraternali, Filippo
• Gault, Lexi
• Piña, Pavel E. Mancera
• Adams, Elizabeth A. K.
• Leisman, Lukas

Abstract

<jats:title>Abstract</jats:title><jats:p>Ultra-diffuse galaxies have generated significant interest due to their large optical extents and low optical surface brightnesses, which challenge galaxy formation models. Here we present resolved synthesis observations of 12 H <jats:sc>i</jats:sc>-bearing ultra-diffuse galaxies (HUDs) from the Karl G. Jansky Very Large Array, as well as deep optical imaging from the WIYN 3.5 m telescope at Kitt Peak National Observatory. We present the data processing and images, including total intensity H <jats:sc>i</jats:sc> maps and H <jats:sc>i</jats:sc> velocity fields. The HUDs show ordered gas distributions and evidence of rotation, important prerequisites for the detailed kinematic models of Mancera Piña et al. We compare the H <jats:sc>i</jats:sc> and stellar alignment and extent, and find that H <jats:sc>i</jats:sc> extends beyond the already extended stellar component and the H <jats:sc>i</jats:sc> disk is often misaligned with respect to the stellar one, emphasizing the importance of caution when approaching inclination measurements for these extreme sources. We explore the H <jats:sc>i</jats:sc> mass–diameter scaling relation, and find that, although the HUDs have diffuse stellar populations, they fall along the relation with typical global H <jats:sc>i</jats:sc> surface densities. This resolved sample forms an important basis for more detailed study of the H <jats:sc>i</jats:sc> distribution in this extreme extragalactic population.</jats:p>

Topics

• impedance spectroscopy
• surface