Journal article
DISTANCE DETERMINATIONS TO SHIELD GALAXIES FROM HUBBLE SPACE TELESCOPE IMAGING
The Astrophysical journal, Vol.785(1), pp.1-13
04/10/2014
DOI: 10.1088/0004-637X/785/1/3
Abstract
The Survey of Hi in Extremely Low-mass Dwarf (SHIELD) galaxies is an ongoing multi-wavelength program to characterize the gas, star formation, and evolution in gas-rich, very low-mass galaxies. The galaxies were selected from the first similar to 10% of the Hi Arecibo Legacy Fast ALFA (ALFALFA) survey based on their inferred low Hi mass and low baryonic mass, and all systems have recent star formation. Thus, the SHIELD sample probes the faint end of the galaxy luminosity function for star-forming galaxies. Here, we measure the distances to the 12 SHIELD galaxies to be between 5 and 12 Mpc by applying the tip of the red giant method to the resolved stellar populations imaged by the Hubble Space Telescope. Based on these distances, the Hi masses in the sample range from 4x10(6) to 6x10(7)M(circle dot), with a median Hi mass of 1x10(7)M(circle dot). The tip of the red giant branch distances are up to 73% farther than flow-model estimates in the ALFALFA catalog. Because of the relatively large uncertainties of flow-model distances, we are biased toward selecting galaxies from the ALFALFA catalog where the flow model underestimates the true distances. The measured distances allow for an assessment of the native environments around the sample members. Five of the galaxies are part of the NGC 672 and NGC 784 groups, which together constitute a single structure. One galaxy is part of a larger linear ensemble of nine systems that stretches 1.6 Mpc from end to end. Three galaxies reside in regions with 1-9 neighbors, and four galaxies are truly isolated with no known system identified within a radius of 1 Mpc.
Details
- Title: Subtitle
- DISTANCE DETERMINATIONS TO SHIELD GALAXIES FROM HUBBLE SPACE TELESCOPE IMAGING
- Creators
- Kristen B. W. McQuinn - University of MinnesotaJohn M. Cannon - Macalester CollegeAndrew E. Dolphin - RTXEvan D. Skillman - University of MinnesotaJohn J. Salzer - Indiana University BloomingtonMartha P. Haynes - Cornell UniversityElizabeth Adams - Cornell UniversityIan Cave - Macalester CollegeEd C. Elson - University of Cape TownRiccardo Giovanelli - Cornell UniversityJuergen Ott - National Radio Astronomy ObservatoryAmelie Saintonge - Max Planck Institute for Astrophysics
- Resource Type
- Journal article
- Publication Details
- The Astrophysical journal, Vol.785(1), pp.1-13
- Publisher
- Iop Publishing Ltd
- DOI
- 10.1088/0004-637X/785/1/3
- ISSN
- 0004-637X
- eISSN
- 1538-4357
- Number of pages
- 13
- Grant note
- NAS5-26555 / NASA; National Aeronautics & Space Administration (NASA) 1211683 / Direct For Mathematical & Physical Scien; National Science Foundation (NSF); NSF - Directorate for Mathematical & Physical Sciences (MPS) Brinson Foundation GO-12658 / NASA from the Space Telescope Institute AST-1211683; AST-0607007 / NSF; National Science Foundation (NSF) University of Minnesota; University of Minnesota System
- Language
- English
- Date published
- 04/10/2014
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984627323002771
Metrics
1 Record Views