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WIYN Integral-Field Kinematics of Disk Galaxies

Matthew Bershady·Marc Verheijen·David Andersen
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Abstract

We have completed a new fiber array, SparsePak, optimized for low-surface-brightness studies of extended sources on the WIYN telescope. We are now using this array as a measuring engine of velocity and velocity-dispersion fields of stars and ionized gas in disk galaxies from high to low surface-brightness. Here we present commissioning data on the velocity ellipsoids, surface densities and mass-to-light ratios in two blue, high surface-brightness, yet small disks. If our preliminary results survive further observation and more sophisticated analysis, then NGC 3949 has sigma_z/sigma_R >> 1, implying strong vertical heating, while NGC 3982's disk is substantially sub-maximal. These galaxies are strikingly unlike the Milky Way, and yet would be seen more easily at high redshift.

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Matthew Bershady, Marc Verheijen, David Andersen. 2002-01-24. WIYN Integral-Field Kinematics of Disk Galaxies. https://arxiv.org/abs/astro-ph/0201407

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