After checking everything, and I mean everything on this instrument for the last 5 days, I finally got the courage to try a sample that we’ve measured before and compare their count rates. I chose a Si crystal that we had measured in reflection before. Just as I had feared, the count rates were 2-3 times worse…I scratched my head raw trying to think of things that were different that I hadn’t checked. I called Jerry..he came up with a few reasons that seemed somewhat plausible, but somewhat unsatisfying. “We were double-counting on the oxfords before…I think” (that kind of stuff). Finally, he told me to just go back and get some rest. I had bought a bottle of sam smith’s brown ale to celebrate, but it didn’t seem fitting. As I finally turned out the last light around 1:30 am, I realized that 2-3 is approximately e, which is the attenuation length of the foil I was using to calibrate the energy right before starting the silicon sample–egads! I raced to the car and drove furiously to the sector only to realize that in my haste I had forgotten my entry badge…so I raced back to the hotel and back to the beam and lo and behold, the goddamn calibration sample was still up, blocking so many photons from my silicon. I’m glad I tracked it down…finally. Now I can sleep, victorious.

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