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arXiv · 1706.08555

HI in Virgo's "Red and Dead" Dwarf Ellipticals - A Tidal Tail and Central Star Formation

Gregory Hallenbeck·Rebecca Koopmann·Riccardo Giovanelli·Martha P. Haynes·Shan Huang·Lukas Leisman·Emmanouil Papastergis
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Abstract

We investigate a sample of 3 dwarf elliptical galaxies in the Virgo Cluster which have significant reservoirs of HI. We present deep optical imaging (from CFHT and KPNO), HI spectra (Arecibo) and resolved HI imaging (VLA) of this sample. These observations confirm their HI content and optical morphologies, and indicate that the gas is unlikely to be recently accreted. The sample has more in common with dwarf transitionals, although dwarf transitionals are generally lower in stellar mass and gas fraction. VCC 190 has an HI tidal tail from a recent encounter with the massive spiral galaxy NGC 4224. In VCC 611, blue star-forming features are observed which were unseen by shallower SDSS imaging.

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Gregory Hallenbeck, Rebecca Koopmann, Riccardo Giovanelli, Martha P. Haynes, Shan Huang, Lukas Leisman, Emmanouil Papastergis. 2017-06-26. HI in Virgo's "Red and Dead" Dwarf Ellipticals - A Tidal Tail and Central Star Formation. https://doi.org/10.3847/1538-3881%2Faa7c1d

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