Robert E. Pollock

Robert Elwood Pollock was born on 2 March 1936 in Regina, Saskatchewan, Canada. He spent the majority of his professional career in the physics department of Indiana University, implementing innovative concepts for accelerators and nuclear physics experiments. After a period of decline, Bob died peacefully at a retirement facility on 28 August 2018, surrounded by his family. He is survived by his wife of 59 years, Jean, four children, and two grandchildren.

When he was 12, Bob’s family moved to Winnipeg, Manitoba. After his undergraduate education at the University of Manitoba, Bob went to the US, where in 1963 he earned his PhD in nuclear physics at Princeton University with a measurement of proton total cross-sections using the first cyclotron in Palmer Hall. Subsequently, he played a leading role in the construction of the new Princeton AVF cyclotron.

Because of his growing reputation as a cyclotron expert, Bob was asked by Indiana University to lead the effort to complete realization of the innovative design for their new 200 MeV cyclotron on the Bloomington campus. Bob accepted the challenge in 1970; the first beam was produced in 1976. Under Bob’s directorship, the Indiana University Cyclotron Facility (IUCF) developed into a major nuclear research center, operated as an international user facility and funded by NSF. Aside from being an administrator, Bob was responsible for improvements to the accelerator, additions to the experimental equipment and, with feedback from the Program Advisory Committee, for the scientific output of the facility. In addition, he found the time to collaborate with some of the research groups and to supervise PhD students.

In 1980 Bob resigned as director of IUCF to pursue the novel concept of electron cooling, a technique invented in Novosibirsk, but recently demonstrated at 200 MeV at FNAL in the US. In this process, a proton beam orbiting in a magnetic storage ring is partly overlapped by an electron beam of the same velocity. Interactions between the two beams lead to a vast improvement of proton beam momentum spread and lifetime, allowing the stored beam to survive even after billions of passes through a thin internal target. Bob had the vision that this would yield a completely new high-resolution and low-background environment for nuclear physics experiments, and he set out to create the first facility in the world to make use of it.

After a planning phase, a proposal was accepted by NSF in 1981, Indiana University contributed a new building, and construction of the “Indiana Cooler” started in the spring of 1983. In the following years, Bob was at the helm of a group of about 30 physicists, engineers, and technicians. Success came in 1988 with the first cooled beam on an internal target. In addition, the storage ring acted as a synchrotron, extending the energy range of beams available at IUCF to 500 MeV protons. In 1997, a compact injector synchrotron of Bob’s design was added, making the Cooler facility independent of the cyclotron. Up until the shutdown of the Cooler in 2002, research with the facility was marked by many “world’s firsts,” with Bob actively collaborating on several experiments. Its success spawned other electron cooling storage rings at several worldwide laboratories.

Bob was awarded a Humboldt Research Award from the German Alexander von Humboldt Foundation in 1985, and he was the co-recipient of the 1992 Tom W. Bonner prize, the highest APS honor in nuclear physics.

Indiana University recognized Bob’s contributions to nuclear physics with a Distinguished Professorship (1984) and the President’s Medal (2011). Bob retired in 2001 but remained active, continuing research and supporting students involved in experimental studies of charged-particle plasmas in Penning traps.

Bob at once excelled in nuclear physics, in the physics of beams and plasmas, and in electrical engineering. His thoughtful insights, conveyed quietly and collegially, were highly valued on advisory panels, including the US Nuclear Science Advisory Committee and many laboratory committees in the US (e.g. Nevis, SUNY, LBL, MSU, LIGO, Bates, ORNL, FNAL) and abroad (e.g. TRIUMF, Canada; COSY, Germany; CELSIUS, Sweden; KVI, The Netherlands; and RIKEN and RCNP, Japan).

As a person, Bob had a friendly and calm demeanor and an understated but ever-present sense of humor. We all remember, for instance, how he, eyes twinkling, would complete a calculation with his well-worn slide rule while we were still entering numbers on our calculators. Bob will be fondly remembered by his colleagues.