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 In Memorium Taro Tamura 1923-1988 |
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Taro Tamura died of a heart attack on 10 October 1988, at the age of 65. He was a distinguished theoretical nuclear physicist who made important contributions to the theory of nuclear reactions and nuclear structure. He received the Argonne Universities Association Distinguished Scientist Award in 1972 and a Senior U.S. Scientist Award from the Alexander von Humboldt Foundation in 1981. He was a member of the Japanese Physical Society and a Fellow of the American Physical Society. Tamura was born in Akita, Japan on July 12, 1923. He earned an undergraduate degree in naval architecture from the University of Tokyo in August of 1945. This period of his life he would mention later only to his closest friends and, even then, usually only as "the darkest days of my life." One of his assignments was apparently to design a sort of manned torpedo or kamikazi submarine! The war over, he returned to the University of Tokyo to study physics, receiving a bachelor's degree in March of 1949 and his Ph. D. in August of 1955. He was a research assistant at the Tokyo University of Education (now Tsukuba University) from 1953 to 1955, a postdoctoral fellow at Niels Bohr Institute in Copenhagen from 1955 until 1957 and at UCLA from 1957 until 1959. He then returned to Tokyo University of Education as an Associate Professor, leaving in 1962 to become a staff physicist at Oak Ridge National Laboratory. He came to the University of Texas as a Professor in 1968, and remained until the end of his life. During his 38-year career in physics, Tamura published about 200 papers. His early work (1950 Ð 55) was mainly in the area of cosmic ray physics but, shortly after he joined the Tokyo University of Education, he became interested in theoretical nuclear physics. Tamura's nuclear theoretical work was at first rather formal and mathematical dealing, for instance, with the relation of nuclear collective coordinates to nucleonic ones, and the application of group-theoretical methods to nuclear spectroscopy. In Copenhagen and at UCLA, he became impressed with the power of a phenomenological approach which combined formal precision with experimentally guided insights into workable approaches and approximations. Tamura immediately appreciated the importance that electronic computers, beginning to appear in the late 1950's, had for the future of theoretical nuclear physics. At UCLA, he witnessed first-hand the impact of early optical model calculations on the field. His move from Japan to Oak Ridge was motivated almost entirely by the computational power he thereby gained access to. At Oak Ridge he completed his famous coupled channels program Jupitor for the description of inelastic scattering to collective excitations of nuclei - over the years it has found widespread use, not only in the fields of nuclear physics and chemistry, but also in nuclear engineering elsewhere. His equally famous article in Reviews of Modern Physics (37, 679 [1965]) summarized the theoretical work that led to the creation of Jupitor and its many applications. In 1966, Tamura became interested in the theory of isobaric analog resonances, and this was one of the major factors in influencing him to transfer from Oak Ridge to the University of Texas where there was not only a large, fast computer, but also a vigorous experimental program generating much novel data shedding light on the role such resonances played in nuclear reactions and scattering. Tamura was always eager to set up arrangements in which he could work closely with experimentalists, and thereby stay abreast of the very latest experimental work in the field. By 1970 he had begun to study a variety of reaction-channel-coupling effects in nuclear reactions, particularly (p,t) reactions. Pursuing these effects into the field of heavy ion reactions, by 1975 Tamura was doing massive exact-finite-range coupled-reaction-channel calculations. During the same period, he formulated a general method for making boson expansions of microscopic collective nuclear Hamiltonians, and for the remainder of his life he was occupied in pushing this complex and powerful method to its limits. In the late 1970's he became interested in the description of the continuum spectra of nuclear reactions in terms of multi-step direct reactions, and this approach he also pursued with characteristic vigor for the remainder of his career. During the final year of his life, he had also become enthusiastic about extending his expertise into the area of theoretical condensed matter physics, and completed a short paper on gradient expansions in density functional theory, and was teaching a course in low energy electron diffraction at the time of his death. No one who ever saw Tamura at work could forget the sight. His energy and powers of concentration were genuinely impressive. He ran to the water fountain so as to provide the minimal interruption to his efforts. In person, he was unfailingly kind, gentle, and modest. It was easy to get him to talk about physics, but very difficult to get him to talk about himself, and almost impossible to get him to review his own achievements. Students found him a never-failing source of inspiration, while colleagues and collaborators found him a never-failing source of workable ideas, compact formalisms, and neat computational tricks. His famous computer programs were models of compactness and clarity. He was an effective teacher, preparing densely written lecture notes which seemed to explore every possible ramification of a subject. While a very quiet and private man, Tamura never shrank from getting actively involved in sometimes heated public discussions concerning the value of some theoretical approach or achievement. Shortly after he came to Texas in the late 1960's, he fell seriously ill. He recovered quickly, and seemed to work as vigorously as ever, but at home he developed a number of relaxing hobbies, including painting in oils and watercolor, growing roses and creating beautiful arrangements with them, and listening to classical music. His health remained good until the spring of 1988 - despite fatigue, and hospitalization for pneumonia, he characteristically planned a full summer of activities, including lectures in Japan, Italy, and Czechoslovakia. A heart attack soon after arrival in Japan put an end to these plans, and Tamura devoted his energies to getting well enough to return to Texas in the fall and resume his duties. Unfortunately, a final heart attack occurred within a month of Tamura's arrival back in Texas, where he had plunged into his teaching and research duties with characteristic vigor. The night before his death he had stayed up past midnight working on lecture notes for his course. During the final decade of his life, Tamura was passionately interested in furthering close scientific cooperation between the Theory Group at Texas and various groups and individuals in Japan. He frequently expressed his love for both his native land, Japan, and his adopted land of Texas. He spoke of the new spirit of increasing economic and scientific competitiveness that had arisen in Japan as well as the generous, friendly, and independent spirit he found characteristic of Texans. He delighted in bringing them together. Both Texas and Japan may find him irreplaceable. TAKESHI UDAGAWA RORY COKER The University of Texas Austin, Texas |