Interstellar bubbles were proposed in the 70's to explain the
Copernicus detection of interstellar OVI absorption lines.
A variety of bubble models are available, but the model by
Weaver et al. (1977) is by far the most well-cited. In their
pressure-driven bubble model, a bubble consists of a dense
shell of swept-up ambient medium and its interior is filled
with shocked fast wind at X-ray-emitting temperature. At the
interface between the hot interior gas and the cool nebular
shell, heat conduction takes place and produces a layer of
10^5 K gas, where highly ionized C, N, and O exist.
Multi-wavelength observations are needed to acquire a
comprehensive picture of bubbles. The advent of Chandra,
XMM-Newton, and FUSE finally made it possible to see the hot
gas in bubble interiors. I will discuss why we see so few
bubbles at visible wavelengths, and report X-ray and FUV views
of bubbles.
Tuesday, November 12th at 4:00 p.m.
Seminar is scheduled to be held in F235 of
the Tech Building, due to current renovations at Dearborn Observatory.
Refreshments will be served at 3:30
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