In Memoriam: Edward Bryan Wagner

1922-2015

by Fred F. Haywood

A respected and beloved coworker, Edward Bryan Wagner passed away 19 January 2015 at his home in Oak Ridge, Tennessee, at the age of 93. He was born 14 January 1922 in Greeneville, Tennessee.

Throughout his adult life, Bryan was a ham radio operator, using the call letters of W4MDX. He enjoyed hunting, fishing, golf, and flying radio-controlled model planes. Bryan served with the 78^th Army Air Force from 1942 to 1946. Shortly thereafter, he joined the Health Physics Division at Oak Ridge National Laboratory (ORNL), where he concentrated on radiation detection system research until retirement in the 1980s. Bryan, or E.B. as he was known to many of his coworkers, was heavily involved in the development of radiation detection systems associated with gamma-ray dosimetry. Through the years, he worked alongside John Auxier, Sam Hurst, Fred Sanders, John Thorngate, John Poston, Sr., Troyce Jones, George Kerr, Philip Perdue, Joseph Cheka, Richard Gammage, and William Shinpaugh.

John Auxier's Radiation Dosimetry Section of the ORNL Health Physics Division was home to many of us during the 1950s and 1960s. It was one of the principal research organizations partnered with the Atomic Bomb Casualty Commission in Hiroshima, Japan, with a mission to determine radiation doses to survivors of the bombings of Hiroshima and Nagasaki. This was a period when much attention was given to neutron and gamma-ray dosimetry research.

One of Bryan's early interests was the separate measurement of dose from coexistent neutron and gamma radiation fields. He noted that when an ionization-type detector such as the C-CO₂ chamber was used to measure the gamma-ray component of a mixed radiation field, its sensitivity to neutrons was such that a considerable error was noted in gamma-ray dose when the neutron to gamma-ray dose ratio was greater than 1. Thus he concentrated on demonstrating that a small halogen-type Geiger-Müller (GM) counter could be surrounded with suitable shields to provide an instrument that was (a) energy independent for x or gamma radiation above about 200 keV, (b) insensitive to fast neutrons, and (c) insensitive to thermal neutrons. An article by Bryan and Sam Hurst in Health Physics, Volume 5, 1961, showed the counter selected for this work was a Phillips No. l8509 micro GM counter filled with neon, argon, and a halogen-quenching agent. It provided readings of exposure in roentgens that were essentially independent of gamma-ray energies down to 150 keV by shielding it with thin layers of tin and lead on the sides and on the end. In radiation fields with thermal neutrons, a thin-walled aluminum shell containing ⁶Li surrounded the probe. This detector, coupled with a small portable battery-powered scaler developed by Bryan and John Thorngate, became very useful for low-level gamma-ray measurements in research as well as for radiation surveys. This detector is currently manufactured by several makers of portable radiation detectors.

Perhaps the most interesting research for Bryan was during his last 20 years of service at ORNL. He joined Sam Hurst's group in research using tuned dye lasers with a mission to detect small quantities of atoms. The team, consisting of Hurst, Marvin Payne, Bryan, Jack Young, and Munir Neyfeh, concentrated on the combination of proportional counters and laser beams to detect atoms. This research led to the detection of a single atom of cesium, and as a result of this research, the team was selected for an I-R 100 Award (now called the R&D 100 Award) from the magazine Industrial Research in September 1976.

Bryan was preceded in death by his parents and his son Lynn Wagner. He is survived by his wife of 68 years, Anita Nichols Wagner; sons, Van Wagner of Oak Ridge and Daryl Wagner and wife Jenny of Knoxville; daughter, Cheryl Wagner of Knoxville; five grandchildren; and nine great-grandchildren.