Obituary of Ziemowid “Ziemek” Sujkowski

Ziemowid “Ziemek” Sujkowski, Director of the Institute for Nuclear Studies (former Institute of Nuclear Research) for ten years, died on July 9, 2006 after a heroic battle with cancer.

Ziemek was born in Warsaw in 1933 as the son of Zbigniew Sujkowski (a university professor of geology) and Idalia (a school teacher of geography). His parents were involved in underground activities during the German occupation of Poland. His mother died in Auschwitz; his father had to escape to London and died in Canada. In 1951 Ziemek began his physics studies at Warsaw University. After earning his master’s degree, he began to work in the newly established Institute of Nuclear Research in Swierk near Warsaw. Soon afterwards he was invited to the Nobel Institute in Stockholm, where he completed his Ph.D. and “Venia Legendi” theses at Stockholm University.

His early research interests were in the Auger process and on the interaction of gamma radiation with K and L electrons of heavy atoms. His fascination with research on the interface between atomic and nuclear physics stayed with him throughout his professional career. Nuclear spectroscopy always played a leading role in his scientific activities. His studies of the properties of nuclei at high angular momentum were first performed by observation of radioactive decays and, later on, by means of tools of “in-beam” spectroscopy.

Ziemek was a leading player in establishing international collaborations in Polish nuclear physics. During 1964-1980, as Head of the Physics Department of the Institute of Nuclear Research (IBJ - Swierk), he managed to compose a team of enthusiastic young physicists working in various European institutes. This was a remarkable achievement in those difficult times.

His personal collaboration with KVI Groningen, lasting over 20 years, concentrated mainly on nuclear structure, especially in-beam gamma-ray spectroscopy, giant resonances, nuclear matter compressibility, etc. In particular, through his experimental work, he contributed to the experimental validation of the Interacting Boson Model. A series of papers on the structure of nuclei close to the magic neutron number 82, and the first observation of the high-spin yrast trap in this region are also worth noting.

In the eighties, he initiated cooperation with Fribourg University on multiple inner-shell ionization accompanying nuclear collisions. Experimental studies of atomic effects in bare hydrogen- and helium-like very heavy atoms, and X-ray spectroscopy of heavy-ion atomic collisions were continued under his supervision at GSI Darmstadt and PSI Villigen. Studies of the properties of atoms ionized by energetic ion beams were performed at GSI and RCNP (Osaka). During the last years, Ziemek initiated the use of his technique of radiative transitions and coincidence experiments in the search for Majorana neutrinos. In particular, he pushed the long-forgotten idea of neutrino-less double electron capture, and he proposed to look for Majorana neutrinos in helicity flip measurements in boosted neutrino sources - the beta beams.

Sujkowski played a significant role in Polish scientific life. He was the Director of the Institute for Nuclear Studies in Swierk/Warsaw for the last 10 years. He served on a number of scientific boards of Polish institutes and universities. The Nuclear Physics Board of the European Physical Society also appreciated his input.

Sujkowski was an exceptional mentor for young scientists. He supervised theses of 21 Ph.D. students in Poland and abroad. Although he set rigorous standards, Ziemek’s enthusiasm and dedication helped him provide an unparalleled learning environment for students. He gave students real responsibility and demanded results, but offered advice at every step of the research work. He didn’t suffer fools gladly!

Ziemek was well known in the international nuclear physics community as Chairman of the Mazurian Lakes Conference in Poland that he led since 1989. He transformed the traditional (dating back to 1968) Nuclear Summer School towards a general subatomic conference. The selection of topics was linked not only to his personal range of research, but also reflected his keen awareness of the state of subatomic physics. It will be quite a challenge to maintain the spirit of the conference without Ziemek.

e will remember Ziemek Sujkowski for his many contributions to the progress of nuclear physics and the promotion of international collaborations. We will remember him for his work on a wide range of topics in nuclear, particle, astro-particle and atomic physics. Even more, we shall remember him for his outstanding personal contributions to generations of physicists, his fierce honesty, his remarkable cheerfulness and sense of humor, and his deep commitment to bringing out the best in others.

Friends and colleagues from the Andrzej Soltan Institute and Warsaw University

Warsaw, Poland