GBT24B-319

Distances to Low-Surface Brightness Satellite Galaxies

Abstract

We request 85.5 hours of observations to use the GBT to search for the HI reservoirs of 66 Local Volume dwarf satellite candidates discovered around nearby low-mass hosts. The proposed observations will allow us to measure distances to individual candidates (using the redshift of the 21 cm HI emission line) and confirm that the discovered objects are physically associated with a given host and not background contamination. Dwarf galaxies are regarded as cosmological and astrophysical probes on small-scales, thus their discovery and characterization are among the most important goals in the field. Though much effort has been made in surveying Milky Way-mass galaxies and their satellite populations, the sample of satellites around lower-mass hosts is much less comprehensive. This proposal is part of a larger campaign to establish a statistical sample of dwarf satellite populations with secure distances around Large Magellanic Cloud and Small Magellanic Cloud mass hosts. If our satellite candidates are confirmed, the current sample of dwarf satellites around low-mass galaxies will be increased by more than a factor of 4. The sample will provide quantitative constraints for galaxy formation physics and serve as an important benchmark for simulations to try and recover.

Investigators

Name	Institution
GBT Operator	Green Bank Observatory
Laurella Marin	Dartmouth College
Laura Hunter *	Indiana University; Dartmouth College
Michael Jones	Arizona, University of
Kristine Spekkens	Queen's University
David Sand	Arizona, University of; Texas Tech University
Paul Bennet	Space Telescope Science Institute
Catherine Fielder	Arizona, University of; Pittsburgh, University of
Denija Crnojevic	Texas Tech University; Tampa, University of
Burcin Mutlu-Pakdil	Dartmouth College
Ananthan Karunakaran	Toronto, University of

* indicates the PI