Gerold Rosenbaum’s #My1stLight

From Gerold Rosenbaum – Advanced Photon Source user

A Playful Use of the Last 10 Minutes of a Run Turns Out to be Very Educational

In 1967, after finishing data collection on the DESY XUV beamline on the polarizer/polarization analyzer I had built for my diploma thesis, there were 15 minutes to go before the synchrotron was to be shut down. Since I always wanted to know how good the vacuum had to be for working in the XUV, I suggested to bleed up the 1-m-long sample chamber to 1/10000 atm or 0.08 torr. The playful use of the last 10 minutes of the run turned out to be an impressive demonstration of the superiority of the continuous spectrum of synchrotron radiation over other XUV sources (paired with a high-resolution monochromator). The very low intensity below 800 Å, even though at the peak of the monochromator spectrum, told me clearly where vacuum-UV starts.

Journal reference: R.P. Godwin, “Synchrotron radiation as a light source,” Springer-Verlag Tracts in Modern Physics 51, p.66, 1969.