41 research outputs found
W51 IRS 2: A Massive Jet Emerging from a Molecular Cloud into an H II Region
We have mapped [Ne II] (12.8um) and [S IV] (10.5um) emission from W51 IRS 2
with TEXES on Gemini North, and we compare these data to VLA free-free
observations and VLT near-infrared images. With 0.5" spatial and 4 km/s
spectral resolution we are able to separate the ionized gas into several
components: an extended H II region on the front surface of the molecular
cloud, several embedded compact H II regions, and a streamer of high velocity
gas. We interpret the high velocity streamer as a precessing or fan-like jet,
which has emerged from the molecular cloud into an OB star cluster where it is
being ionized.Comment: 3 pages, 4 figures, 2 movie
Quantum Imaging with Incoherently Scattered Light from a Free-Electron Laser
The advent of accelerator-driven free-electron lasers (FEL) has opened new
avenues for high-resolution structure determination via diffraction methods
that go far beyond conventional x-ray crystallography methods. These techniques
rely on coherent scattering processes that require the maintenance of
first-order coherence of the radiation field throughout the imaging procedure.
Here we show that higher-order degrees of coherence, displayed in the intensity
correlations of incoherently scattered x-rays from an FEL, can be used to image
two-dimensional objects with a spatial resolution close to or even below the
Abbe limit. This constitutes a new approach towards structure determination
based on incoherent processes, including Compton scattering, fluorescence
emission or wavefront distortions, generally considered detrimental for imaging
applications. Our method is an extension of the landmark intensity correlation
measurements of Hanbury Brown and Twiss to higher than second-order paving the
way towards determination of structure and dynamics of matter in regimes where
coherent imaging methods have intrinsic limitations
Recommended from our members
Proceedings, Western juniper management short course, October 15-16, 1984, Bend, Oregon
Published 1984. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo