A direct image and spectrum in H-band (1.62 microns) of the Seyfert
galaxy NGC4151.
The direct image (top left) was taken through the 68 milli-arcsec slit, and
shows magnified the central core of the galaxy, with a width of about
80 mas, and with diffuse structure extending about 100 mas on either
side.
The spectrum (top right) is the difference between two raw 1024x1024 600s high-resolution
spectra, with the object nodded 254 mas along the slit between the two
images. The result is a negative and positive image of the spectrum
displaced by the nod distance. The plot shows a cross section of the
subtracted image pair, with an measurement of the S/N achieved in the spectrum.
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