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arXiv · 1305.0270

ALFALFA Discovery of the Nearby Gas-Rich Dwarf Galaxy Leo~P. II. Optical Imaging Observations

Katherine L. Rhode·John J. Salzer·Nathalie C. Haurberg·Angela Van Sistine·Michael D. Young·Martha P. Haynes·Riccardo Giovanelli·John M. Cannon·Evan D. Skillman·Kristen B. W. McQuinn·Elizabeth A. K. Adams
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Abstract

We present results from ground-based optical imaging of a low-mass dwarf galaxy discovered by the ALFALFA 21-cm HI survey. Broadband (BVR) data obtained with the WIYN 3.5-m telescope at Kitt Peak National Observatory (KPNO) are used to construct color-magnitude diagrams of the galaxy's stellar population down to V_0 ~ 25. We also use narrowband H-alpha imaging from the KPNO 2.1-m telescope to identify an HII region in the galaxy. We use these data to constrain the distance to the galaxy to be between 1.5 and 2.0 Mpc. This places Leo P within the Local Volume but beyond the Local Group. Its properties are extreme: it is the lowest-mass system known that contains significant amounts of gas and is currently forming stars.

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Katherine L. Rhode, John J. Salzer, Nathalie C. Haurberg, Angela Van Sistine, Michael D. Young, Martha P. Haynes, Riccardo Giovanelli, John M. Cannon, Evan D. Skillman, Kristen B. W. McQuinn, Elizabeth A. K. Adams. 2013-05-01. ALFALFA Discovery of the Nearby Gas-Rich Dwarf Galaxy Leo~P. II. Optical Imaging Observations. https://doi.org/10.1088/0004-6256%2F145%2F6%2F149

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