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DOE OSTI · 22089822

LITTLE THINGS

Hunter, Deidre A.·Herrmann, Kimberly A.·Johnson, Megan·Hongxin, Zhang·Ficut-Vicas, Dana·Brinks, Elias·Heesen, Volker·Ashley, Trisha·Simpson, Caroline E.·Cigan, Phil·Westpfahl, David J.·Young, Lisa M.·Elmegreen, Bruce G.·Oh, Se-Heon·Rupen, Michael P.·Schruba, Andreas·Walter, Fabian
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Abstract

We present LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes, The H I Nearby Galaxy Survey), which is aimed at determining what drives star formation in dwarf galaxies. This is a multi-wavelength survey of 37 dwarf irregular and 4 blue compact dwarf galaxies that is centered around H I-line data obtained with the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA). The H I-line data are characterized by high sensitivity ({<=}1.1 mJy beam{sup -1} per channel), high spectral resolution ({<=}2.6 km s{sup -1}), and high angular resolution ({approx}6''). The LITTLE THINGS sample contains dwarf galaxies that are relatively nearby ({<=}10.3 Mpc; 6'' is {<=}300 pc), that were known to contain atomic hydrogen, the fuel for star formation, and that cover a large range in dwarf galactic properties. We describe our VLA data acquisition, calibration, and mapping procedures, as well as H I map characteristics, and show channel maps, moment maps, velocity-flux profiles, and surface gas density profiles. In addition to the H I data we have GALEX UV and ground-based UBV and H{alpha} images for most of the galaxies, and JHK images for some. Spitzer mid-IR images are available for many of the galaxies as well. These data sets are available online.

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79 ASTRONOMY AND ASTROPHYSICSASTROPHYSICSCALIBRATIONDATA ACQUISITIONDENSITYGALAXIESHYDROGENIMAGESLUMINOSITYMAPPINGRADIOASTRONOMYRESOLUTIONSENSITIVITYSTAR EVOLUTIONSTARSVELOCITYWAVELENGTHS

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Hunter, Deidre A., Herrmann, Kimberly A., Johnson, Megan, Hongxin, Zhang, Ficut-Vicas, Dana, Brinks, Elias, Heesen, Volker, Ashley, Trisha, Simpson, Caroline E., Cigan, Phil, Westpfahl, David J., Young, Lisa M., Elmegreen, Bruce G., Oh, Se-Heon, Rupen, Michael P., Schruba, Andreas, Walter, Fabian. 2012-11-01. LITTLE THINGS. https://doi.org/10.1088/0004-6256%2F144%2F5%2F134

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