PI: Tomer Tal, Yale University, email@example.com
Address: Astronomy Department, P.O. Box 208101, New Haven, CT 06511, USA
CoI: Jeffrey D.P. Kenney, Yale University
Title: H(alpha) Observations of Gravitationally Interacting Ellipticlas
Abstract: We propose to obtain deep H(alpha) Mosaic images of ten gravitationally interacting giant elliptical galaxies in search for H(alpha) features that may provide evidence for gravitational ISM heating. The observed H(alpha) filaments can reveal important clues to the origin of the warm phase of elliptical galaxies, how it is ionized, and how it relates to the other phases of the ISM. We have suggestive evidence for gravitational heating in the Virgo elliptical M86 from our recent results which show a remarkable set of H(alpha) filaments connecting the galaxy to the spiral NGC 4438. The filaments indicate a recent collision between the galaxies and the spatial correlation of Ha and X-ray emission suggest that the high X-ray luminosity of M86 may be due to the collision. We propose similar Ha observations in 10 elliptical galaxies selected for their disturbed stellar morphologies, all showing signs for recent gravitational activity. Observing these galaxies can help us shed light on the relation between gravitational interactions and the observed properties of the ISM of elliptical galaxies.
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