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Prof. Dr. Dr. h.c. Gustav-Adolf Voss. A Life for Accelerators. Wilhelm Bialowons Gustav-Adolf Voss ∙ A Life for Accelerators 23 rd Meeting of the SESAME Council Sweimeh ∙ Jordan ∙ November 25, 2013. Outlook: Gustav-Adolf Voss ∙ A Life for Accelerators.
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Prof. Dr. Dr. h.c. Gustav-Adolf Voss A Life for Accelerators Wilhelm Bialowons Gustav-Adolf Voss ∙ A Life for Accelerators 23rd Meeting of the SESAME Council Sweimeh∙ Jordan ∙ November 25, 2013
Outlook: Gustav-Adolf Voss ∙ A Life for Accelerators • Prologue: Wake Field Transformer Experiment at DESY • Early Life, Education and Learning Phase • First Merits: CEA Bypass and DORIS Commissioning • His Masterpiece: PETRA • The late Work: HERA • The Visionary • The Human • Awards • Epilogue • References
Prologue In 1981 I met Gustav-Adolf Voss the first time at DESY. At the beginning he was the advisor of my diploma thesis and later of my PhD thesis. He accompanied me more than half of my life up to some weeks before he did on October 5 this year in the age of 84 in Hamburg. He was my boss up to his retirement end of 1994. In the first time he asked me nearly always, when I met him on the floors, for an appointment for coffee in his office. Later my office was opposite to his but it was much smaller. Then he came mostly on Friday afternoon to my office and we discussed all the weekly problems in the machine division. One of this problems was the dramatically drop down of the beam lifetime in the HERA electron ring, which limited the current to about 5 % of the design value. But part of the time we talked also about private things. After his retirement I met him regularly mostly for lunch at DESY but also at his home for fruitful discussions about Physics in general, accelerator physic for sure, all the problems in this world, music, especially classical music, but this is not my thing, audio books and movies with audio description because he became blind at the about last fifteen years. I will miss these discussions in the future and I will miss him.
Early Life, Education and Learning Phase • Gustav-Adolf Voss was born near Berlin on July 20 in 1929. • After high school (Gymnasium) he studied at the Technical University in Berlin. His Diploma thesis he was about the construction of a Thomson Mass Spectrograph under the advisor Prof. Ramsauer. • He completed his PhD thesis “Über die LichtanregungdurchIonen des leichten und schwerenWasserstoffs” in 1955. The advisors were Prof. Hanke and Prof. Boesch. • Gustav-Adolf Voss joined DESY for the first time at beginning of 1958 and stayed in Hamburg for two and a half year interrupted by a yearly stay at the Cambridge Electron Accelerator in Boston. • In the early days of DESY (official approval was given at the end of 1959) he joined a group responsible for the construction of the injection linac for the 6 GeV Electron Synchrotron. Therefore, the name of our institute is DeutschesElektronen-Synchrotron DESY.
First Merits: CEA Bypass • In the year 1960 Gustav-Adolf Voss moved permanently to the Cambridge Electron Accelerator and he stayed there for 14 years. In 1964 he was appointed as Associate Director of the Laboratory. • At that time the Cambridge Electron Synchrotron was upgraded by a bypass to a colliding electron positron storage ring. This extremely challenging project generated a number of innovations to which he made essential contributions. • One is the low beta insertion for focusing the both beams at the interaction point to extremely low sizes to get sufficient luminosity (normalized collisions per time unit). Only this makes high energy physic experiments in storage rings possible. • This became a saga of hardship, triumph and great intellectual achievements and led in the seventies to the construction of several dedicated storage rings all over the world. One of them was DORIS in Hamburg.
First Merits: DORIS Commissioning • Beginning of 1973 G.-A. Voss returned to DESY as head of the Machine Division and Vice Chairman of the Board of Directors. • The double electron positron storage ring DORIS was nearly completed. But a serious of key components and system were not operational and Voss had to find solutions. • Gus Voss solved these problems in his inimitable style by “probing, challenging conventional wisdom, encouraging, simplifying complex suggestions, driving everybody into exhaustion and never losing the sight of the goal.” • End of 1973 DORIS came out and had luminosity beginning of 1974. • By that time every day counted because some month earlier the November Revolution had taken place. The J/Ψparticle with rather unusual properties had been found independently at BNL and SLAC (SPEAR) by Samuel Ting and Burton Richter. Later they awarded both the Nobel price for the discovery of the new particle. • DORIS was rebuilt several times and finally shut off January this year.
His Masterpiece: PETRA • Electron-Positron storage ring with a circumference of 2.3 km at DESY in Hamburg with at that time highest beam energy of 23.4 GeV. • First stored electrons on July 15, 1978. • Nine month ahead of the original schedule and only two years and nine month after the project had been authorized. • A little bit less than the authorized 100 Million DM were spent. • PETRA’s design and construction are still considered exemplary for all modern electron storage rings. • 1979 PETRA discovered the gluon, the “glue” that holds together the quarks in the building blocks of atomic nuclei, which is one of the greatest scientific achievements of DESY. • Robert Wilson: “The fast progress in PETRA can be attributed to the elegant and sparse design of G.-A. Voss.” In Scientific American. • PETRA was rebuilt several times later on and is today one of the most intense synchrotron light sources in the world.
His Masterpiece: PETRA In 1978 G.-A. Voss explains the machine to the German President Walter Scheel.
His Masterpiece: PETRA On July 15, 1978 G.-A. Voss and his team celebrates the first stored electrons. (Helmut Wiedemann, Anton Piwinski, AlbinWrulich and Dieter Trines.)
The late Work: HERA Ten years later on August 20, 1988 celebration of the first stored electrons in HERA.
The late Work: HERA • Electron-Proton double storage ring with a circumference of 6.3 km at DESY in Hamburg. The 900 GeV proton machine consist mainly of superconducting magnet. The 30 GeV electron machine was equipped partially was superconducting cavities. • Gustav-Adolf Voss was responsible for the buildings (four large underground halls and the ring tunnel about 20 m below surface), for the construction of the electron storage ring and the pre-accelerator chain. BjörnWiik was in charge of the proton machine. • The approval was given in 1984. The construction started in the same year. The facility was constructed in an international collaboration (HERA model) within budget and time. • First stored electrons August 1988. First stored protons in April 1991. First collision in the same year. • One unique feature of the electron ring was the possibility of longitudinal spin polarisation at three interaction points. • HERA was switched off mid of 2007.
The late Work: HERA On October 19, 1991 celebration of the first electron proton collision with BjörnWiik. (Ferdinand Willeke and ReinhardBrinkmann.)
The Visionary • In the early 1980s he initiated already studies of novel accelerating schemes for Linear Collider and designed a low cost normal conducting 500 GeV Linear Collider at DESY in Hamburg. • For the far future a Wake Field Transformer Experiment was made at DESY on the one side. This experiment studied the acceleration of electrons by wake fields exited by a high current hollow beam. • For near future a test facility for improving acceleration with S-Band structures was set up on the other side. One result was an improvement of the brazing of the copper structures by an induction heating. • Both subjects are still up to date (International Linear Collider and Plasma Wakefield acceleration). • But last not least after retirement he got passionately engaged in the synchrotron radiation facility SESAME, which is an international project brings together in science the states in the Middle East.
The Human • Gustav-Adolf Voss was a world citizen and he liked the One World idea. • Already at the PETRA time, scientists from the Peoples Republic of China joined the Mark J High Energy Physics detector, but specially during HERA construction he supported very strongly the cooperation of Scientist from East and West especially from East and West Germany. In my opinion this was one of the small pieces which led at the end to the reunification of Germany and opening of East Europe (Fall of the wall and the iron curtain). • I even think that this was the most fascinating idea for him to initiate support SESAME a science project for the countries in the Middle East. • I’m not the right person to reward it appropriate but I’m hoping that you all will accomplish his dream. • To complete the picture of the human Voss he was also interested in other persons problems and last but not least he liked classical music very much.
Awards • For his long-standing merits in science, his essential contributions to the development of particle accelerators, for his commitment to support eastern European scientists after the breakdown of the Soviet Union and for his dedication to SESAME Prof. Gustav-Adolf Voss received numerous awards, among which are • The Order of Merit of the Federal Republic of Germany, • The honorary doctorate (Dr. h. c.) of the University of Heidelberg, • The prestigious Tate Medal of the American Institute of Physics and • For his numerous merits for our laboratory in 2009 Gustav-Adolf Voss became the first person to receive the DESY Golden Pin of Honour, which was awarded to him during the colloquium on the occasion of his 80th birthday.
Epilogue • Gustav-Adolf Voss was one of the best in his field and he influenced the most of the modern accelerator. • Before commissioning of the HERA electron machine a Hamburg newspaper published an interview under the title “Der Herr der Speicherringe” in analogy to the title of the fantasy novel “The Lord of the Rings” by J. R. R. Tolkien. • This inspired DESY to give the colloquium on the occasion of his 80thbirthday the motto “Lord of the Rings”. • Herman Winicksaid in his eulogy during the funeral on October 12: “He was a truly ‘Lord of the Rings’.” • “With the death of Gustav-Adolf Voss, the DESY research centre has lost one of its most influential figures. His charismatic leadership, expert skills and foresight have greatly contributed to DESY’s current standing as an internationally leading accelerator laboratory. We owe him our sincere gratitude and will always hold him in high regard.” From DESY mourns Gustav-Adolf Voss.
References Sources which I have used: • Speech by Professor Björn H. Wiik at the colloquium in honor of Gustav-Adolf Voss on May 26, 1995 at DESY in Hamburg. • Gustav-Adolf Voss, 1929 – 2013 by ReinhardBrinkmann in DESY inForm November 2013. • Obituary for Gustav-Adolf Voss by William Barletta, Robert Klanner and Herman Winick to be published in NIM-A. • DESY News 7.10.2013 “DESY mourns Gustav-Adolf Voss“.