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arXiv · 1511.05069

Limits on the HI content of the dwarf galaxy Hydra II

Andrew Janzen·Eve M. Klopf·Felix J. Lockman·Rodolfo Montez Jr·Kurt Plarre·Nau Raj Pokhrel·Robert J. Selina·A. Togi·Mehrnoush Zomederis
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Abstract

Sensitive 21cm HI observations have been made with the Green Bank Telescope toward the newly-discovered Local Group dwarf galaxy Hydra II, which may lie within the leading arm of the Magellanic Stream. No neutral hydrogen was detected. Our 5-sigma limit of MHI < 210 solar masses for a 15 km/s linewidth gives a gas-to-luminosity ratio MHI/L_V < 2.6 x 10^{-2} Mo / Lo. The limits on HI mass and MHI/L_V are typical of dwarf galaxies found within a few hundred kpc of the Milky Way. Whatever the origin of Hydra II, its neutral gas properties are not unusual.

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Andrew Janzen, Eve M. Klopf, Felix J. Lockman, Rodolfo Montez Jr, Kurt Plarre, Nau Raj Pokhrel, Robert J. Selina, A. Togi, Mehrnoush Zomederis. 2015-11-16. Limits on the HI content of the dwarf galaxy Hydra II. https://doi.org/10.1051/0004-6361%2F201527332

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