Vadim Nikolaevitch Lebedenko passed away on 11^th May 2008, whilst at home in Moscow.

Vadim Nikolaevitch was born on 11^th October 1939 in the village Shakhta-2, in the Donezk region, eastern Ukraine. His childhood, during difficult war and post-war times, was spent in this coal mining region. After secondary school he entered an industrial technical school that led him into industry for several years. This was followed by 3 years of military service in the Soviet Army.

He was then admitted to the Moscow Engineering and Physics Institute. He graduated with distinction in experimental nuclear physics in 1968, under supervision of Prof. Boris Rodionov, and went on to obtain his PhD with Prof. Boris Dolgoshein as supervisor. In Prof Dolgoshein’s laboratory, he worked on the development of a liquid argon spark chamber operated in streamer mode. Vadim constructed a liquid argon ionisation chamber which re-discovered the effect of electron emission from liquid to gas and applied it to radiation detection, obtaining the first images of an alpha-particle source placed in the liquid by using a multiwire spark chamber in the gas phase. This was the first two-phase emission detector and a clear demonstration of the potential of this technique for the detection of ionising particles.

In 1970s Vadim joined the Institute of High Energy Physics in Protvino, working on a liquid argon calorimeter for particle physics. He also proposed a system of argon purification with hot getters and began work on microchannel-plate position-sensitive detectors. He was a member of the team which constructed MARS-I, the first of several very large scale liquid argon calorimeters built at the institute.

In 1983 he moved to the Institute of Theoretical and Experimental Physics, to the laboratory headed by Prof. Lyubimov, where he applied his skills to further the development of microchannel-plate detectors, as well as scintillation detectors for the E761 experiment at Fermilab, a hadron-blind detector for high energy physics and cryogenic detectors based on liquefied noble gases.

Around this time he was invited to M.I.T. by Prof. Min Chen to work on a liquid xenon scintillation calorimeter for the proposed US accelerator SSC, a project which attracted a number of physicists from leading Russian institutions in the field.

In 1998, Vadim joined a new international dark matter experiment, ZEPLIN-III (UK, Russia and Portugal), moving to Imperial College London in 2000 to undertake most of the design and construction work in the team led by Prof. Tim Sumner. This novel double-phase xenon detector, presently taking scientific data at the Boulby Underground Laboratory, UK, owes its original design, final engineering realisation and assembly to Vadim Nikolaevitch. His role as the “father” of ZEPLIN-III is undisputed in the collaboration: he took it from a mere design concept to a final instrument, a true statement of skill, knowledge and resolve, from an outstanding scientist who mastered both the most intricate physics and the most challenging engineering. He passed away at the moment when his detector had just started to measure relevant physical data, culminating his decade-long endeavour.

He will always be remembered as an excellent scientist and engineer, cheerful friend, excellent person and a teacher for many of us always ready to share his unique knowledge and experience.

Contributions by A. Bolozdynya, D. Akimov, V. Chepel, T. Sumner