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Title: VLA Imaging of HI-bearing Ultra-Diffuse Galaxies from the ALFALFA Survey
Here we present resolved HI and deep optical imaging of 11 HI-bearing ultra-diffuse galaxies (HUDs) from the Karl G. Jansky Very Large Array and the WIYN 3.5m at Kitt Peak National Observatory. We find that the HUDs show blue, mostly irregular stellar populations, and ordered gas distributions with evidence of rotation. Comparing the HI and stellar populations, we find that the HI extends significantly beyond the stellar component, and that the HI disk is often misaligned with respect to the stellar one. We explore the HI mass-diameter scaling relation, and find that though the HUDs have diffuse stellar populations, they fall along this relation, with typical global HI surface densities. We also use 3D kinematic modeling to explore the Baryonic Tully Fisher Relation, and find that the HUDs fall off the relation, rotating too slowly for their baryonic mass, and are compatible with having no "missing baryons."
Authors:
; ; ; ; ;
Award ID(s):
1637339
Publication Date:
NSF-PAR ID:
10168210
Journal Name:
American Astronomical Society meeting
Volume:
235
Page Range or eLocation-ID:
168.23
ISSN:
2152-887X
Sponsoring Org:
National Science Foundation
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