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We present a combination of new and archival neutral hydrogen (HI) observations and new ionized gas spectroscopic observations for 16 galaxies in the statistically representative Extended Disk Galaxy Explore Science kinematic sample. HI rotation curves are derived from new and archival radio synthesis observations from the Very Large Array (VLA) as well as processed data products from the Westerbork Radio Synthesis Telescope (WSRT). The HI rotation curves are supplemented with optical spectroscopic integral field unit (IFU) observations using SparsePak on the WIYN 3.5 m telescope to constrain the central ionized gas kinematics in 12 galaxies. The full rotation curves of each galaxy are decomposed into baryonic and dark matter halo components using 3.6μm images from the Spitzer Space Telescope for the stellar content, the neutral hydrogen data for the atomic gas component, and, when available, CO data from the literature for the molecular gas component. Differences in the inferred distribution of mass are illustrated under fixed stellar mass-to-light ratio (M/L) and maximum disc/bulge assumptions in the rotation curve decomposition. [ABSTRACT FROM AUTHOR]

We present results from multiwavelength observations of the galaxy NGC 5005. We use new neutral hydrogen (HI) observations from the Very Large Array to examine the neutral gas morphology and kinematics. We find an HI disc with a well-behaved flat rotation curve in the radial range 20-140 arcsec. Ionized gas observations from the SparsePak integral field unit on the WIYN 3.5 m telescope provide kinematics for the central 70 arcsec. We use both the SparsePak and HI velocity fields to derive a rotation curve for NGC 5005. Deep 3.6 μm observations from the Spitzer Space Telescope probe the faint extended stellar population of NGC 5005. The images reveal a large stellar disc with a high surface brightness component that transitions to a low surface brightness component at a radius nearly 1.6 times farther than the extent of the gas disc detected in HI. The 3.6 μm image is also decomposed into bulge and disc components to account for the stellar light distribution. Optical broad-band B and R and narrowband Hα from the WIYN 0.9 m telescope complement the 3.6 μm data by providing information about the dominant stellar population and current star formation activity. The neutral and ionized gas rotation curve is used along with the stellar bulge and disc light profiles to decompose the mass distributions in NGC 5005 and determine a dark matter halo model. The maximum stellar disc contribution to the total rotation curve is only about 70 per cent, suggesting that dark matter makes a significant contribution to the dynamics at all radii. [ABSTRACT FROM AUTHOR]