Early Results from the Wisconsin H-Alpha Mapper Southern Sky Survey

L. M. Haffner; R. J. Reynolds; G. J. Madsen; A. S. Hill; K. A. Barger; K. P. Jaehnig; E. J. Mierkiewicz; J. W. Percival; N. Chopra

arXiv · 1008.0612

Early Results from the Wisconsin H-Alpha Mapper Southern Sky Survey

L. M. Haffner·R. J. Reynolds·G. J. Madsen·A. S. Hill·K. A. Barger·K. P. Jaehnig·E. J. Mierkiewicz·J. W. Percival·N. Chopra

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Abstract

After a successful eleven-year campaign at Kitt Peak, we moved the Wisconsin H-Alpha Mapper (WHAM) to Cerro Tololo in early 2009. Here we present some of the early data after a few months under southern skies. These maps begin to complete the first all-sky, kinematic survey of the diffuse H-alpha emission from the Milky Way. Much of this emission arises from the Warm Ionized Medium (WIM), a significant component of the ISM that extends a few kiloparsecs above the Galactic disk. While this first look at the data focuses on the H-alpha survey, WHAM is also capable of observing many other optical emission lines, revealing fascinating trends in the temperature and ionization state of the WIM. Our ongoing studies of the physical conditions of diffuse ionized gas will continue from the southern hemisphere following the H-alpha survey. In addition, future observations will cover the full velocity range of the Magellanic Stream, Bridge, and Clouds to trace the ionized gas associated with these neighboring systems.

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L. M. Haffner, R. J. Reynolds, G. J. Madsen, A. S. Hill, K. A. Barger, K. P. Jaehnig, E. J. Mierkiewicz, J. W. Percival, N. Chopra. 2010-08-03. Early Results from the Wisconsin H-Alpha Mapper Southern Sky Survey. https://arxiv.org/abs/1008.0612

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