Obituary of Hans Henrik Andersen (1937-2002)

There is sad news about our colleague and friend Hans Henrik Andersen, emeritus professor of physics at the University of Copenhagen, who died of cancer on 3 Nov 2012. Hans Henrik was a leading experimentalist in the field of ion-beam physics and widely respected for his experience and judgement. He gave several pioneering contributions to the field, the most original of which may have been his idea to measure charged-particle stopping calorimetrically at liquid-helium temperature, which he carried through in his ph.d. thesis at Risø, Denmark 1962–65. This gave rise to data with an accuracy not seen before in this area which even now, half a century later, still form the state-of-the-art. At the University of Aarhus, Denmark, Hans Henrik gave pioneering contributions to the understanding of sputtering, both by original ideas such as using molecular ions as projectiles, and by raising experimental standards. The amount and diversity of experimental data and profound knowledge gained from this effort is truly monumental. Hans Henrik was generous in communicating his experience in books and numerous reviews, and more directly to his students, junior researchers and colleagues, locally and internationally. He has served the scientific community in numerous functions. Most wellknown may be his role as a founding editor of NIMB, to which he devoted much of his time for almost thirty years, but he has also served as a department head and as a dean of Science in Copenhagen and Aarhus, respectively, as chairman of the Danish Science Research Council, as a delegate in CERNs council and as a member of numerous governing boards and advisory committees. There will be many of us, who will miss him.