Near-Infrared Stellar Kinematics in Luminous Galaxies

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Session 77 -- Spirals II
Display presentation, Wednesday, 11, 1995, 9:20am - 6:30pm

[77.03] Near-Infrared Stellar Kinematics in Luminous Galaxies

Niall I. Gaffney, Dan F. Lester, Rodney S. Heyd, Greg W. Doppmann (University of Texas at Austin)

We use the 2.3 $\mu$m stellar CO absorption bandhead to measure kinematics in the near-infrared for a number of optically obscured galaxies. Using the unextinguished elliptical galaxy M32 as a test case, we validate our least-squares fitting and maximum entropy deconvolution methods by comparing our results to that determined optically. Measuring stellar and ionized gas kinematics in the starburst galaxies M82 and NGC 253, we test to see if gas kinematics trace the true gravitational potential as defined by the stars. Using the masses derived from these measurements, we explore the nature of the stars which dominate the near infrared luminosity. In M82, our results imply that both young and old stars are responsible for the K morphology. This explains the differences in the morphology of the K light, which traces the stars both young and old, and the ionized gas, which traces the regions of new star formation. We also examine the stars in the center of the galactic merger NGC 6240. We derive a mass-to-luminosity ratio that is consistent with those found in quiescent galaxies. This suggests that the source of this galaxy's high luminosity is not young luminous stars as had been previously speculated but rather the conglomeration of two old massive bulges. We recently applied this technique to derive the mass distribution in the nearby Seyfert 2 galaxy NGC 1068 to determine the mass of its nucleus. Initial results from this study will also be presented.

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