Bruce Patterson's memories of Ken Crowe

I had the pleasure of being Ken's grad student during the years 1972-1975, during the formative period of the muon spin rotation (µSR) technique, at the 184-inch cyclotron. Group members at the time included Jess Brewer, Richard Johnson, and, from Switzerland, Fredy Gygax. It was the Swiss connection initiated by Fredy that ultimately brought me to my present home, at the University of Zurich and the Paul Scherrer Institut.

The Swiss connection also almost destroyed my office in Ken's suite in Building 50. My thesis project was to use µSR to measure internal fields in ferromagnets. The muon beam at the 184 inch cyclotron required big samples, and Ken allowed me to buy what was probably the one of the world's largest single crystals of nickel -- a phallic rod, 4 cm in diameter and 20 cm long. My first job, upon receiving it, was to check its crystal quality. Upon Fredy's recommendation, I did this by going to the second member of the Swiss conspiracy, his high-school buddy Gervais Chapuis, who was doing a post-doc at LBL in crystallography. Gervais, in turn, took me to the third Swiss, Eugene Haller, who prepared a horrible mixture of strong acids with which to etch the surface of the phallus, in order to make visible any grain boundaries. In a non-typical Swiss fashion, Eugene mixed far too much of the acid solution. After performing the etch -- and determining that the crystal was anything but single -- he thoughtfully put the remainder in a 5 liter polyethelene bottle -- "in case you want to repeat the etch", making sure to tightly screw on the lid.

I knew enough chemistry to understand the danger of this mixture, and although I temporarily placed the bottle on the desk in my office, I was planning after lunch to move it to the dangerous chemical storage at the cyclotron. Unknown to me, there was a small piece of nickel left in the acid in the closed bottle. So, during lunch, we heard fire sirens and an emergency announcement of "an acid spill in Building 50". I rushed to the office, to find a squad of white-clad firemen with gas masks and thick rubber gloves spraying neutralizing agents and installing ventilators. Of course, the etching reaction had continued on the small Ni piece, creating sufficient pressure to rupture the bottle, which then became a rocket -- flying around the office and spraying acid everywhere. My physics textbooks carry the scars to this day.

A result of this Swiss misadventure was that several days later, an offical emergency action report was posted on all the bulletin boards of LBL. Here was written that "an experimental physicist neglected to follow correct safety procedures". On one of the copies, some wag had scrawled "Acid bust at LBL!" Ken's reaction to the whole affair was remarkably relaxed. In a memorable piece of Crowe ironic humor, he told me to "save the safety report as a confirmation that you are indeed an experimental physicist."

Thanks, Ken, for your inspiration, guidance and friendship. I will miss you.