GBT26A-555

SEAMLESS HI follow-up of extremely low mass galaxy candidates

Abstract

We request 43.35h of GBT observations to investigate the HI properties of 26 dwarf galaxies that are potentially some of the lowest mass star-forming galaxies in the Local Volume. The observed properties of low-mass galaxies have repeatedly pushed the boundaries of the Lambda-CDM paradigm, presenting difficult challenges on small scales. Through the combination of the Legacy Imaging Surveys and a specially trained convolutional neural network, the SEmi-Automated Machine LEarning Search for Semi-resolved galaxies (SEAMLESS) has already identified some of the lowest mass star-forming galaxies known. The candidates we wish to follow up here are from the same search, but lack any existing observations of their neutral gas. Although we anticipate detecting HI in the vast majority of our targets (which have been selected based on evidence of recent star formation), the observations have been designed such we will be able to confidently conclude that any non-detections are gas-poor objects, potentially raising questions about how they are able to form stars. Detections will allow us to determine gas fractions, velocity widths, and velocities, revealing the basic nature of these objects and allowing us to prioritize further follow-up.

Investigators

Name	Institution
GBT Operator	Green Bank Observatory
Michael Jones *	California Institute of Technology
David Sand	Arizona, University of; Texas Tech University
Ananthan Karunakaran	Toronto, University of
Kristine Spekkens	Queen's University
Burcin Mutlu-Pakdil	Dartmouth College
Catherine Fielder	Arizona, University of; Pittsburgh, University of
Dennis Zaritsky	Arizona, University of
Richard Donnerstein	Arizona, University of
Donghyeon Khim	Arizona, University of
Deepthi Prabhu	Arizona, University of
Laura Hunter	Indiana University; Dartmouth College
Amandine Doliva-Dolinsky	Dartmouth College
Denija Crnojevic	Texas Tech University; Tampa, University of
Paul Bennet	Space Telescope Science Institute

* indicates the PI