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Title: SHIELD: EVLA HI Spectral Line Observations of Low-mass Dwarfs
The “Survey of HI in Extremely Low-mass Dwarfs” (SHIELD) is a multiwavelength study of local volume low-mass galaxies. Using the now-complete Arecibo Legacy Fast ALFA (ALFALFA) source catalog, 82 systems are identified that meet distance, line width, and HI flux criteria for being gas-rich, low-mass galaxies. These systems harbor neutral gas reservoirs smaller than 3x10^7 M_sun, thus populating the faint end of the HI mass function with statistical confidence for the first time. Here we present new Karl G. Jansky Very Large Array D-configuration HI spectral line observations of 32 previously unobserved galaxies. These low angular resolution (~40" beam) images localize the HI gas; with a few exceptions, the HI gas is co-spatial with the optical centers of the galaxies. These images provide the first glimpse of the neutral interstellar medium in these systems.Support for this work was provided by NSF grant 1211683 to JMC at Macalester College.
Authors:
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Award ID(s):
1637339
Publication Date:
NSF-PAR ID:
10030116
Journal Name:
American Astronomical Society ... meeting
Volume:
229
Page Range or eLocation-ID:
145.11
ISSN:
2152-887X
Sponsoring Org:
National Science Foundation
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