Václav Vrba, our classmate, friend and colleague passed away after a long illness on Tuesday, December 29. His life’s pilgrimage crossed ours in a number of places and for years in our working as well as personal lives and it is difficult for us to accept that it no longer will be so.
We met in Břehová street in 1968 in the third grade of Nuclear Physics specialisation at the Faculty of Mathematics and Physics of the Charles University where Václav transferred from FTJF (now the Faculty of Nuclear Sciences and Physical Engineering of the Czech Technical University) and we from the MFF UK.
After graduation, we started working at the Institute of Physics of the former Czechoslovak Academy of Sciences. Two of us joined a group studying collisions of antiprotons and protons in the Ludmila bubble chamber in Serpukhov near Moscow, where the most powerful accelerator in the world for a short time was located in the first half of the 1970s. The experiment took place from about the mid-1970s to the mid-1980s in collaboration of laboratories from Almaty, SUJV Dubna, Moscow, Helsinki, Košice and Prague.
The group at the Institute of Physics was led by Vláďa Šimák who passed away last year and who was our teacher and his love of physics inspired us. A large part of today's older generation of Czech elementary physicists began in this experiment, in which Prague played a very dignified role. At that time, Václav focused on the processing of experimental data and their analysis, which in practice meant mainly programming. We still remember vividly how we carried boxes with punched cards to what would seem a monster today, but was a top IBM 370 then and we spent long nights together right in the hall. In 1975 Václav went to work on this experiment at SÚJV Dubna.
After defending his dissertation, he joined a group there which included, for example, Jan Řídký and Miloš Lokajíček and also Rupert Leitner from the Faculty of Mathematics and Physics. The group was preparing a detector for the DELPHI experiment on the LEP accelerator, which was being built at CERN and in which the collisions of opposing electron and positron beams were investigated.
After November 1989 two closely collaborating groups were formed fast at the Institute of Physics and the Faculty of Mathematics and Physics which joined the DELPHI experiment directly from Prague. Václav and Jan Řídký and other collaborators from the Institute of Physics significantly contributed to the experiment by developing special detection tubes for a hadron calorimeter. Gradually, Václav became more and more focused on the development of detectors. This remained true for the rest of his life and he established himself in this field on a global scale.
DELPHI was a huge experiment with about 300 co-authors and a number of other technical staff. It ran from the early 1990s until the end of the millennium, and data were processed for many more years. A whole generation of young physicists was trained there and Václav matured there.
The peak of his scientific career came with the ATLAS experiment on the LHC accelerator, which is located in the same 27-kilometre tunnel as DELPHI and where the collisions of two opposing proton beams are being investigated. This experiment is even an order of magnitude larger than DELHI and it was not easy to succeed in tough international competition. Václav was one of the main initiators of the involvement of the physicists from our institute in this experiment and he managed to find an important area in which he made a significant contribution to this experiment. This was and is the development, testing and construction of pixel trajectory detectors, which represent the heart of every current elementary particle collision detector.
For this experiment, Václav built a modern laboratory of semiconductor detectors at the Institute of Physics and got a number of talented students from the Faculty of Mathematics and Physics and the Czech Technical University to work in it. Ten years ago, he got an opportunity to build another laboratory at the FJFI in Břehová street, where the centre of his activities was shifted later.
He became a top expert in the development of pixel detectors, not only for the ATLAS experiment. The detectors he developed in his lab with his students and colleagues have also found application elsewhere, such as the PHENIX experiment at the RHIC accelerator at the Brookhaven National Laboratory in the United States, where collisions of opposing beams of heavy nuclei, such as lead, are being studied, and we could mention also other projects. His group also developed special pixel detectors for imaging methods in medicine, and these detectors have an ever-widening field of application. There are many talents among Václav's students, so we don't have to worry about the future of this area, which Václav founded in our country.
However, Václav’s life was not only physics and detectors; he was an active sportsman. During his stay at the SÚJV, he even ran marathons, he enjoyed cycling and loved so called Czech Canada, which he regularly visited with his wife Helena and where he became famous as a passionate blueberry picker. We will still remember the weeks spent together in the beautiful landscape of Czech Canada.