Obituary for Prof. Dr. Jean Kern

Prof. Dr. Jean Kern, member and former President of the Swiss Physical Society (1983-85), died the 27th of March 2000, two days before his 70th birthday, after a serious two-year long illness.

Jean Kern was born in Cannes, France, in 1930 from Swiss parents. His career as a physicist started at ETH Zürich where he graduated in 1954. He moved then to the University of Fribourg where he received his Ph.D. degree in 1959 with a doctorate thesis in nuclear physics performed under the direction of Prof. Dr. O. Huber. The next six years were divided into a post-doc stay in Uppsala in the group of Prof. K. Siegbahn (1959-60), a provisory return to Fribourg as a scientific collaborator, and a second stay abroad, in Tallassee, Florida, in the group of Prof. R.K. Sheline (1963-65). The year 1965 marks the beginning of his 33 year long fruitful academic career at the Physics Institute of the University of Fribourg, starting with an habilitation as lecturer (1966), associate professor (1968), extraordinary professor (1972) and finally ordinary professor (1980). Jean Kern was also elected as Dean of the Faculty of Sciences of the University of Fribourg (1981-82) and Director of the Physics Institute of Fribourg (1985-92).

His name remains closely associated with the field of nuclear structure and particularly with nuclear spectroscopy, a domain in which his merits were recognized world-wide. Many high-performance instruments were developed within his group: pair and anti-Compton spectrometers, multiple coincidence systems, several bent crystal spectrometers for in-beam high-resolution g and X-ray spectroscopy. State-of-the-art (n,g), (a,xng) and (HI,xng) experiments performed by his group mainly at PSI (formerly EIR and SIN) and ILL have permitted a better understanding of nuclear structure, particularly for deformed nuclei. Results published by Jean Kern have been quoted as reliable references in numerous theoretical papers and text books. It is thus not surprising that in 1993 he was chosen to organize the 8th International Symposium on Capture Gamma-Ray Spectroscopy and Related Topics in Fribourg.

However, the scientific interests of Jean Kern were not limited only to nuclear spectroscopy. Applied nuclear physics (development of a Prompt Gamma-Ray Activation Analysis installation at SINQ), nuclear astrophysics (initiator of a BENEFRI agreement in astrophysics), atomic physics (muonic atoms, heavy-ion-induced atomic multiple excitation) and particle physics (CP violation experiment at LEAR) are examples of his activities in other fields. Jean Kern also initiated or proposed several projects which were of interest for the scientific community at large. Some of them were realized such as the upgrade of the PSI variable energy Philips cyclotron with an ECR heavy-ion source which he proposed in 1989 in collaboration with Prof. H. Gäggeler and Dr. P. Schmelzbach. In contrast to that, the organization with Prof. Gäggeler of an international workshop to discuss the feasibility of a PSI radioactive beam facility (1992) did not lead to tangible results, maybe because of the already existing Swiss Light Source project.

During his career Jean Kern has supervised about 30 Ph.D. theses and 50 diploma works. He was recognized by his Ph.D. students and collaborators as an enthusiastic and young-at-heart leader, hard at work and exacting but always fair and close to them.

Besides research, Jean Kern has been also an excellent teacher whose pedagogical qualities have been appreciated by several hundred students for more than 30 years. He has left behind numerous lecture notes in general and modern physics for first and second year students and in nuclear physics. Jean Kern has always considered his teaching duties with great professional commitment. For instance, only a few days before his first hospitalization in September 1997 he was putting the finishing touches on a new manuscript concerning nuclear astrophysics for lectures that he should have given at the University of Bern during the following year.

Jean is survived by his wife, three children, and many grandchildren to whom we address our gratitude and deepest sympathy.

Prof. J.-Cl. Dousse


[Released: January 2001]