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After visiting friends, family and colleagues in Germany, Robert Bruce (Bob) Moore died suddenly en route back to Montreal. With his death, McGill University and the nuclear physics community have lost a remarkable and imaginative physicist, engineer and teacher.

Following his undergraduate Engineering Physics degree at McGill, Bob began graduate studies at McGill’s Radiation Laboratory, earning an M.Sc. degree in beta spectroscopy in 1959. Following this, he opted to continue in a different and more applied direction for a Ph.D.  During its first decade of operation, the McGill 100 MeV proton synchrocyclotron had done only internal target bombardments. The lab director, J.S. Foster, and later, R.E. Bell, recognizing Bob’s engineering background and interests, suggested that as a PhD project he design and build a regenerative beam extraction system.  This really was the beginning of Bob’s lifetime interest in the design of ion dynamics in a variety of systems. The project was successful, and in 1962 the cyclotron produced its first external beam. This gave the cyclotron a new research life, and the laboratory continued to operate for another 3 decades.  The very first experiment done with the extracted beam yielded the lab’s most important result: the discovery of beta-delayed proton radioactivity.  In the years that followed, Bob continued his work on a wide variety of experiments in beta and gamma spectroscopy.  All of these were marked by innovation and ingenuity. He built a pneumatic target extraction system (‘rabbit’) to study isotopes with decay lifetimes of tens of milliseconds. For high-energy beta decay studies he designed and built a novel spectrometer using a superconducting solenoid magnet with an intrinsic germanium detector mounted in the bore.  And during those years, he was the person mainly responsible for rescuing a perennially ailing cyclotron. On one occasion an ion source cooling tube broke and the cyclotron’s vacuum system filled with water like a giant aquarium. On another morning during a run, an internal piece came loose in the large rotating capacitor, and left the copper rotor and stator blades a mangled mess. Bob disassembled the whole thing, and hammered everything back into shape; it ran for another ten years. The worst problem of all was the development of many leaks from the main magnet coils, which were essentially hollow water-cooled rectangular tubes. We decided that these should be repaired by separating all the coil layers and inserting new cooling pads. Bob oversaw the whole operation, and after the repair everything worked perfectly again.  Visitors to the lab often commented on the collection of fried and twisted components on Bob’s windowsill. These were mementos of many past battles with both successful and failed experiments, and Bob had stories about all of them.

It was through several sabbatical leaves that Bob became more widely known in both North America and Europe. In 1972 he spent a year in Vancouver, measuring the magnetic field profile of the new TRIUMF cyclotron. His interest in TRIUMF continued and years later, following workshops in 1984 and 1985, Bob became a major player in a proposal to build an intense radioactive beam facility at TRIUMF, and to construct a TISOL (Test Isotope Separator On-Line) as a prototype facility.  Bob was mainly responsible for the first beam optical design. TISOL was constructed rapidly, and produced its first beam in 1987. Although it was intended mainly to guide the development of the eventual major facility, for more than a decade it carried out a very active physics program, concentrating on nuclear reactions of astrophysical interest.  ISAC is now a world-leading facility, and Bob deserves credit as a key figure in its early development.  In a second sabbatical leave in 1981, Bob spent a year at Mainz and became acquainted with ion traps. When he returned to McGill he was almost evangelical in his description of traps and their capabilities. To say the least, we at McGill thought this was strange: everyone else seemed to be concentrating on accelerators with higher energies and intensities; why try to make ions stand still? Of course, he was right - ion traps for precise mass measurements and for a variety of fundamental tests are present at many major facilities.  Bob continued his collaboration with Mainz on the ISOLTRAP project at CERN, and later on the TITAN ion trap at TRIUMF.  Many of the trap publications during the past 25 years include innovations that Bob suggested, and calculations that he performed on trap dynamics.

Bob was as innovative in his teaching as in his research. He developed new courses, always with imaginative new approaches: The Physics and Psychophysics of Music, was introduced because the music faculty needed a course to accompany a new sound recording option.  His courses on Space, Time and Matter and on Physics for the Life Sciences attracted large numbers of students from all faculties.  He entertained students with optical and acoustic illusions, to emphasize that only with measurements were physicists able to overcome false impressions about the universe.  His lecture demonstrations were scary and spectacular: using exercise equipment, he would suspend himself from the ceiling to make himself the mass on the spring; to introduce the concept of torques and moments he would cantilever a clamped board from the lecture table and walk out on it until it broke. The more likely it was that the demonstration would maim the professor, he often said, the more likely it was that students would remember it. 

If we had visiting seminar speakers or dignitaries, Bob would be the dinner guest of choice. As a native of Windsor, Newfoundland, he had an inexhaustible supply of Newfie jokes and yarns. We thought of him as our own good-natured in-house Rex Murphy, and we could trigger long rants by plying him with key words;  ‘Joey Smallwood’, ‘seal hunt’ ‘bagpipe music’, were a few.  Misuse of the terms ‘precision’ and ‘accuracy’ would produce a half-hour lecture. He was amused and intrigued by irrationalities and complications in systems of units, tormenting theoretical colleagues by asking them to convert E in esu to volts/metre.    He even invented several unit systems of his own, which allowed him to do mental calculations of ion velocities and fields in magnet gaps while the rest of us were fishing out calculators and sheets of paper. 

The spirit of fun and energy that Bob brought to physics carried over in his life outside McGill.  He was the life of the party in every sense. Graduate students, friends and acquaintances will remember the many barbecues, winter broomball games and summer kite-flying expeditions that he organized.  His wife, Ute, sons Daniel and Philipp survive him; all contributed to his many successes. We will always remember him with a smile.

John Crawford, McGill University