Obituary of Edward der Mateosian

Edward der Mateosian, physicist emeritus at Brookhaven National Laboratory, veteran of the Manhattan project, and pioneer in the development of new detectors, electronics, and computers for use in nuclear spectroscopy, died on May 20, 2006. In a long career he was involved in many developments taken for granted in nuclear science today. Ed, as he was known to his friends and colleagues, saw, at an early stage, how important computers would become in experiment and worked closely with new emerging technologies helping to develop the very first data acquisition systems. Ed also made tremendous strides in developing the tools that would allow us to understand the properties of nuclei from beta decay, neutron capture, neutrinos, and gamma-ray spectroscopy. Together with C.S. Wu of Columbia University he wrote one of the most significant works publishing all the known beta spectra of the day and launching studies of weak interactions and fundamental symmetries. The correlations of beta decay with gamma ray emission were first measured by Der Mateosian in the 1950s. He also made one of the earliest attempts to measure the neutrino-less double beta decay transition strength using crystal scintillators, CaF2(Eu). Der Mateosian was also the first to advocate and develop crystal scintillators enriched in the Ca isotopes of interest, namely 48Ca or 40Ca to improve the sensitivity of the technique of using an internal source. This approach is still used today and cited as recently as 2007. It is difficult to pick out his most influential contribution to the understanding of nuclei but it is perhaps his contributions to the developing field of gamma-ray spectroscopy in the late 1960s and early 1970’s with the advent of high resolution solid state detectors such as Ge.

He was a keen experimentalist envisioning what was possible long before the technology had really arrived. He was working closely with crystal growers and detector companies to develop the early solid state detectors for use in the detection of gamma-rays. He broke new ground in understanding the electromagnetic behavior of gamma rays. The work of Der Mateosian and Sunyar on nuclear properties derived from measurements of angular correlations and angular distributions of gamma-rays emitted in reactions as a means of determining the angular momenta of short-lived nuclear states is still the basis of such measurements today. Their tabulated works are still the standards in Nuclear Physics. Together with M. Goldhaber, Ed made systematic studies of isomers in nuclei establishing their existence broadly over the chart of nuclides. Amongst other noteworthy contributions, he also demonstrated the complementarity of neutron capture and heavy ion reactions as tools for deciphering the complex nature of nuclei. Prior to his retirement from Brookhaven National Laboratory, Der Mateosian turned his great experience to evaluating nuclear structure data whilst working at the Nuclear Data Center at BNL.

Der Mateosian was born on Aug 6, 1914 in New York City to a family of Armenian immigrants. He was a man who loved the country that had adopted his family but at the same time was proud of his roots in Armenia. He studied Chemistry at Columbia University for both his Bachelor and Master’s degrees and joined the faculty of Physics at Indiana University briefly in 1941 before being recruited to work on the Manhattan project at the Naval Research Laboratory from 1942-1946. He then worked at Argonne National Laboratory for three years before joining Brookhaven National Laboratory in 1949.

To all of us who knew him Ed Der Mateosian was a true gentleman and a scholar. He cherished his colleagues and associates including M. Goldhaber, Trudy Scharff-Goldhaber, O. Kistner, D. Alburger, A. Sunyar, P, Thieberger, C.S. Wu, G. Friedlander, and J. Tuli as well as many others. In return he was much loved and respected by all those who came in contact with him. He was generous with his time and his heart, possessed boundless enthusiasm and loved life. He loved his wife Anne and it was a great blow to him when she died after a long illness. He loved and was proud of his daughters Maro and Lisa, who were a great comfort to him in his later years. Der Mateosian was always graceful on his feet and he was as well known for his dancing classes with his wife Anne, as for his water colors, or for building sailboats as he was in making great advances in developing new techniques and detectors for nuclear and neutrino science. He is very much missed.