LITTLE: Local Irregulars That Trace Luminosity Extremes
THINGS: The HI Nearby Galaxy Survey
Deidre Hunter (Lowell Observatory)
Elias Brinks (University of Hertfordshire)
Bruce Elmegreen (IBM T. J. Watson Research Center)
Michael Rupen (National Radio Astronomy Observatory)
Caroline Simpson (Florida International University)
Fabian Walter (Max-Planck-Institut für Astronomie)
David Westpfahl (New Mexico Institute of Mining and Technology)
Lisa Young (New Mexico Institute of Mining and Technology)
Trisha Ashley (NASA Ames Research Center, post-doc)
Phil Cigan (Cardiff University, post-doc)
Dana Ficut-Vicus (Astronomical Observatory Cluj-Napoca)
Volker Heesen (Universität Hamburg)
Kim Herrmann (Pennsylvania State University Mont Alto, tenure-track)
Megan Johnson (USNO-DC)
Ged Kitchener (University of Hertfordshire, pre-doc)
Se-Heon Oh (Korea Astronomy and Space Science Institute)
Nau Raj Pohkrel (Florida International University, pre-doc)
Andreas Schruba (Max Planck Institute for Extraterrestrial Physics)
Hong-Xin Zhang (Pontificia Universidad Católica de Chile, post-doc)
The LITTLE THINGS Survey was granted close to 376 hours of time with the VLA in the B, C, and D array configurations 2007-2008 to obtain deep HI-line maps of dwarf galaxies. The purpose is to determine how tiny galaxies form stars. We observed 21 dwarf irregular (dIm) and Blue Compact Dwarf (BCD) galaxies, and are adding another 20 dwarfs with data in the VLA Archives. The new observations consist of 12 hours in B-array, 6 hours in C-array, and 2 hours in D-array for each galaxy. The channel separation is 2.6 km/s for 31 galaxies and 1.3 km/s for 11 galaxies.
The combined B/C/D arrays sample the galaxies at 6 arcseconds, which is 110 pc at 3.7 Mpc, the average distance of our sample. This resolution shows clouds, shells, and turbulent structures that are important for star formation. We also produce maps at lower resolution that reveal the extended, low-density gas around star formation structures and trace the low density HI far beyond the stellar disks.
We are grateful to the National Radio Astronomy Observatory (NRAO) for time on the VLA and the people at the VLA who make things run. The VLA is a facility of the NRAO, itself a facility of the National Science Foundation that is operated by Associated Universities, Inc.
We are also grateful to the National Science Foundation for funding the LITTLE THINGS project with grants to Hunter (AST-0707563), Elmegreen (AST-0707426), Simpson (AST-0707468), and Young (AST-0707835) over the period June 2007-June 2012.
E-mail: dah [at] lowell.edu