EXES Development - Pictures
from the Laboratory November 2000
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The 4" by 4"
square, 40" long EXES grating. The grating was diamond-machined from a
single piece of Al 6061 by Hyperfine, Inc. The hole bored down the center is
to lightweight the grating.
A side view of the
EXES grating. Note the stairstep pattern of the grooves. The dark stripes
are the illuminated faces we care about.
Another view of
the EXES grating.
Looking at the
grating from near blaze. Note the image of the photographer at the far end
of the grating
Lab results from
the TEXES (ground-based prototype) spectrograph with an emission gas cell.
A blow up of the
TEXES gas cell results. Note that the methane lines near 7 microns are not
well fit by a Gaussian. The acetylene lines near 13 microns are very well
fit by a Gaussian.
A TEXES image
(actually a nod pair with the top image positive and the bottom image
negative) of Beta Peg at the IRTF. The top countour is approximately the
FWHM with successive contours down by root(10). There are hints of the Airy
pattern, indicating we were close to the diffraction limit of the telescope.
A pupil image of
the IRTF taken with TEXES. This image shows the secondary mirror and the
spider. TEXES's pupil is about 10% too big; we can see the spider directly
at the edge of our pupil.