| Abstract |
We present new observations of 10000 K ionized gas in the Smith Cloud, a
high velocity cloud thought to be interacting with the interstellar
medium of the Galaxy 3 kpc below the midplane. We have obtained H-alpha,
H-beta, [N II], [S II], and [O III] spectra of the cloud with the
Wisconsin H-Alpha Mapper (WHAM). Previously, we have shown that the
ionized component has a mass of > 106 Mȯ
(comparable to the mass of the neutral component), with relatively
bright H-alpha emission in directions with faint H I 21 cm emission.
Detections of [S II] and [N II] constrain the temperature and
metallicity of the infalling ionized gas. New WHAM observations extend
the H-alpha map to search for diffuse emission not associated with H I
and probe the kinematics and metallicity of the tail. We also report [N
II] and [S II] spectra in four directions along the axis of the cloud in
order to explore the kinematics and metallicity distribution across the
cloud.
WHAM is funded by the National Science Foundation through grant AST
0607512 to the University of Wisconsin-Madison. |