This directory contains spectra of the sky background as observed with
the IRS. 

Data taken with the Cross-dispersed grating are xd.*.sky.gif.
These data were taken on 17 Oct97 on the Blanco 4m with 100 sec
integrations, and the 0.35mm (2 pixel) slit. The weather was clear and
the temperature had been consistently about 5C.  The data are dark
subtracted and extracted along the slit. They are normalized to
ADU/second/pixel.

Data taken with the 75 line 4.5 micron blaze grating are combined in
one spectrum: 75.sky.gif. They were taken the same night, with 60
second integration time, and the 0.35 mm slit.

A 300 second exposure in the H band was also taken. The data, dark
subtracted and normalized are shown in 75.sky.H.gif and a magnified
version in 75.sky.H.mg.gif. This is to indicate the level of the sky
flux between the sky lines.

Brooke Gregory 29Dec97