Alignment Tests of January 14

After a fruitless first engineering night with essentially no astronomical data collected, we re-examined our optical alignment during the day of January 14.  First we went back to the gas cell to verify that we could still find the Q-branch:

Q-Branch collected 1/14 (unsaved screengrab)

Here the spectral lines look reasonably sharp, and we can see evidence of the re-steering we did during the night.  We're shifted about two orders to the right in the display, and he vignetting at the bottom of the image is gone.

Shifting to lo-med, we could still see the Q-branch:

Q-Branch collected 1/14 (unsaved screengrab)

Then, swinging the echelle out of the way, we see an image of the slit (decker wheel open):

Slit image collected 1/14 (unsaved screengrab)

This is through the 14µm filter, and we see diffraction plus a strong glint that is probably coming off the front edge of the echelle mount.

From here we went to the 5µm filter and opened the slit wheel:

5µm camera-mode image of gas cell collected 1/14 (unsaved screengrab)

Here we see that at least one of the wheel apertures was not lined up...turned out to be the slit wheel, but that was being positioned with reference to the data so not a big deal.  After moving the slit wheel by 4 degrees we got a well-aligned s/d/f/cassette:

5µm camera-mode image of gas cell collected 1/14 (unsaved screengrab)

We see the gas cell is a bit off-center, as it was in our prep-room test of January 11.  The instrument is hanging off the telescope here, and might have flexed a little(?)....looks slightly more off-center to me in this image, but the earlier one was at a different wavelength and it's hard to compare.

Next we re-installed the Z-beam and the laser mount, and put a soldering iron behind the laser mount:

5µm camera-mode image of soldering iron collected 1/14 (unsaved screengrab)

The image of the soldering iron is not very round, even though the aperture we're shining it through is pretty close to the IRTF focus.  The hole in the laser holder is cylindrical so maybe reflections coming through the holder would create an angular dependence.