- Email: [email protected]
Recollecting Tom through the history of the RICH Workshop series
Nuclear Instruments and Methods in Physics Research A 502 (2003) 23–25
Recollecting Tom through the history of the RICH Workshop series E. Nappi* INFN-Sezione di Bari, c/o Dip. di Fisica, Via G. Amendola 173, Bari 70124, Italy
1. Introduction . invited me to provide a When T. Ekelof contribution on Tom Ypsilantis at RICH2003, I was very honoured and accepted with enthusiasm. It has been my privilege to know Tom. He had a profound influence upon my career by stimulating and guiding a relevant part of my research activities. My reminiscences on him are tightly interwoven with the history of the RICH Workshop series, thus motivating the title of this manuscript. In 1990, involved in the design and construction of a RICH detector I was impressed by his two seminal manuscripts: ‘‘Photo-ionization and Cherenkov Ring Imaging’’, co-written with J. Seguinot, and ‘‘Cherenkov Ring Imaging’’, published by Nuclear Instruments and Methods in 1977 and by Physica Scripta in 1981, respectively. Afterwards, owing to my growing interest for the Cherenkov light imaging technique, I assiduously studied all his papers, being highly educational and a marvellous source of inspiration for further developments and applications. Tom and Jacques’ manuscripts constantly contained an impressive amount of material clearly describing, in detail, the technical problems they had to overcome along the way, thus making the reader able to reproduce their achievements. Nevertheless, I was surprised that so complex a detector had no
*Tel.: +39-080-544-3171; fax: +39-080-544-2470. E-mail address: [email protected] (E. Nappi). doi:10.1016/S0168-9002(02)02151-4
specific forum where specialists discuss the technologies currently available in this field. In 1993, at the first Workshop on RICH detectors held in Bari, the summary-speaker, A. Breskin, said: ‘‘in order to build and exploit a RICH detector it is not sufficient to be an expert of optics, electronics, solid-state physics and so on, but one must be a magician too’’. I fully share his opinion: design and construction of a RICH detector are a major undertaking. This conviction persuaded me to contact Tom and ask him for his support in organizing a Workshop on Cherenkov light imaging applications.
2. The RICH workshop series In the summer of 1992 I met Tom at CERN, I well remember my excitement in asking him to chair the International Scientific Advisory Committee (ISAC) of the first Conference on RICH detectors to be held in Bari by June 1993. He enthusiastically accepted, providing the premises for the success of the initiative and bringing about the start of a friendship between us that continued unchanged until his death. Thanks to Tom’s influential personality, G. Charpak (awarded, some time before, with the Nobel Prize in Physics) and other prominent physicists joined the ISAC whose first meeting was held in November at CERN: a unanimous agreement on how to organize the Workshop was reached in very short time.
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E. Nappi / Nuclear Instruments and Methods in Physics Research A 502 (2003) 23–25
Today, after four very successful editions, I firmly believe that the Workshop goal to provide a forum for reviewing the experimental aspects with the aim to promote and cross-fertilize more advances in the RICH community has been largely achieved. I would like to convey my deepest appreciation to Tom not only for the endless efforts he spent in organizing the past Workshops but also in providing guidance and advice on difficult matters, which arose from time to time. Moreover, his ability to stimulate discussions on important issues characterized the three editions attended by him. His interventions were often interspersed with amusing remarks; everybody in the audience appreciated his incisive and witty sense of humour very much. Each Workshop marked an important progress, as I will briefly outline in the following. 2.1. RICH93 Bari, June 2–5, 1993 More than 80 participants attended this first Workshop, which coincided with the successful operations of large RICH systems: DELPHI, CRID, CERES, and OMEGA.
thin films of CsI, a photosensitive material intensively pioneered in the past, appeared to be a valid alternative to TMAE and TEA. The very promising ‘‘infant’’ DIRC was presented in the session devoted to ‘‘other developments on Cherenkov counters’’. In few years DIRC will be definitively considered a well-assessed technology. 2.2. RICH95 Uppsala, June 12–16, 1995 This second edition was characterized by presentations testifying the wealth of physics results achieved in experiments with RICH detectors. Although it took years to understand in depth the behaviour of such systems, at the end significant results were obtained. This made Tom particularly proud because he always had in mind the physics objectives. For him, the progress of detector technology was only instrumental to challenge and explore fundamental problems in particle physics. In Uppsala, following the important breakthrough achieved by RD26, CsI became an assessed photon converter for RICH detectors. However, it was also shown that CsI cannot be used in RICH devices operated at high rates (HERA-B). 2.3. RICH98 Ein Gedi, 15–20 November, 1998 Another big success, more than 100 participants attended this edition. The workshop duration was extended to 5 days and following the large number of submitted abstracts, a poster session was organized.
Newly emerging techniques for the photon detection were extensively discussed. In particular
E. Nappi / Nuclear Instruments and Methods in Physics Research A 502 (2003) 23–25
Exciting physics results were shown from SuperKamiokande proving that Cherenkov light imaging is a powerful unmatched technique also in neutrino studies. For the first time, RICHs based on gaseous photon detectors were less numerous than RICHs based on vacuum photon detectors. Tom and Jacques again left their footprint, in this new trend, by promoting large area HPDs manufactured at CERN under their supervision. Still Tom was the protagonist of another outstanding achievement, reported at this Workshop, to which I also contributed: the employment of silica aerogel radiators in Cherenkov light imaging detectors operated in the visible range. Such studies drove the design of the HERMES and LHCb dual radiator RICHs.
3. Conclusions Tom’s influence extends beyond his achievements: his availability and open character made him the friend of everybody, a friend who could always be relied on to give good advice. His office was always open to everybody and often plenty of people from any experiment or part of the world. While I strove to maintain the utmost objectivity in this paper, I am afraid my huge appreciation of Tom makes me biased in my judgement.
25
Hence, I would like to conclude by quoting the following sentence of A. Zichichi: Tom will never be forgotten as a source of constant enthusiasm and new ideas, a passionate friend and an honest, sincere and straightforward colleague.
Recollecting Tom through the history of the RICH Workshop series E. Nappi* INFN-Sezione di Bari, c/o Dip. di Fisica, Via G. Amendola 173, Bari 70124, Italy
1. Introduction . invited me to provide a When T. Ekelof contribution on Tom Ypsilantis at RICH2003, I was very honoured and accepted with enthusiasm. It has been my privilege to know Tom. He had a profound influence upon my career by stimulating and guiding a relevant part of my research activities. My reminiscences on him are tightly interwoven with the history of the RICH Workshop series, thus motivating the title of this manuscript. In 1990, involved in the design and construction of a RICH detector I was impressed by his two seminal manuscripts: ‘‘Photo-ionization and Cherenkov Ring Imaging’’, co-written with J. Seguinot, and ‘‘Cherenkov Ring Imaging’’, published by Nuclear Instruments and Methods in 1977 and by Physica Scripta in 1981, respectively. Afterwards, owing to my growing interest for the Cherenkov light imaging technique, I assiduously studied all his papers, being highly educational and a marvellous source of inspiration for further developments and applications. Tom and Jacques’ manuscripts constantly contained an impressive amount of material clearly describing, in detail, the technical problems they had to overcome along the way, thus making the reader able to reproduce their achievements. Nevertheless, I was surprised that so complex a detector had no
*Tel.: +39-080-544-3171; fax: +39-080-544-2470. E-mail address: [email protected] (E. Nappi). doi:10.1016/S0168-9002(02)02151-4
specific forum where specialists discuss the technologies currently available in this field. In 1993, at the first Workshop on RICH detectors held in Bari, the summary-speaker, A. Breskin, said: ‘‘in order to build and exploit a RICH detector it is not sufficient to be an expert of optics, electronics, solid-state physics and so on, but one must be a magician too’’. I fully share his opinion: design and construction of a RICH detector are a major undertaking. This conviction persuaded me to contact Tom and ask him for his support in organizing a Workshop on Cherenkov light imaging applications.
2. The RICH workshop series In the summer of 1992 I met Tom at CERN, I well remember my excitement in asking him to chair the International Scientific Advisory Committee (ISAC) of the first Conference on RICH detectors to be held in Bari by June 1993. He enthusiastically accepted, providing the premises for the success of the initiative and bringing about the start of a friendship between us that continued unchanged until his death. Thanks to Tom’s influential personality, G. Charpak (awarded, some time before, with the Nobel Prize in Physics) and other prominent physicists joined the ISAC whose first meeting was held in November at CERN: a unanimous agreement on how to organize the Workshop was reached in very short time.
24
E. Nappi / Nuclear Instruments and Methods in Physics Research A 502 (2003) 23–25
Today, after four very successful editions, I firmly believe that the Workshop goal to provide a forum for reviewing the experimental aspects with the aim to promote and cross-fertilize more advances in the RICH community has been largely achieved. I would like to convey my deepest appreciation to Tom not only for the endless efforts he spent in organizing the past Workshops but also in providing guidance and advice on difficult matters, which arose from time to time. Moreover, his ability to stimulate discussions on important issues characterized the three editions attended by him. His interventions were often interspersed with amusing remarks; everybody in the audience appreciated his incisive and witty sense of humour very much. Each Workshop marked an important progress, as I will briefly outline in the following. 2.1. RICH93 Bari, June 2–5, 1993 More than 80 participants attended this first Workshop, which coincided with the successful operations of large RICH systems: DELPHI, CRID, CERES, and OMEGA.
thin films of CsI, a photosensitive material intensively pioneered in the past, appeared to be a valid alternative to TMAE and TEA. The very promising ‘‘infant’’ DIRC was presented in the session devoted to ‘‘other developments on Cherenkov counters’’. In few years DIRC will be definitively considered a well-assessed technology. 2.2. RICH95 Uppsala, June 12–16, 1995 This second edition was characterized by presentations testifying the wealth of physics results achieved in experiments with RICH detectors. Although it took years to understand in depth the behaviour of such systems, at the end significant results were obtained. This made Tom particularly proud because he always had in mind the physics objectives. For him, the progress of detector technology was only instrumental to challenge and explore fundamental problems in particle physics. In Uppsala, following the important breakthrough achieved by RD26, CsI became an assessed photon converter for RICH detectors. However, it was also shown that CsI cannot be used in RICH devices operated at high rates (HERA-B). 2.3. RICH98 Ein Gedi, 15–20 November, 1998 Another big success, more than 100 participants attended this edition. The workshop duration was extended to 5 days and following the large number of submitted abstracts, a poster session was organized.
Newly emerging techniques for the photon detection were extensively discussed. In particular
E. Nappi / Nuclear Instruments and Methods in Physics Research A 502 (2003) 23–25
Exciting physics results were shown from SuperKamiokande proving that Cherenkov light imaging is a powerful unmatched technique also in neutrino studies. For the first time, RICHs based on gaseous photon detectors were less numerous than RICHs based on vacuum photon detectors. Tom and Jacques again left their footprint, in this new trend, by promoting large area HPDs manufactured at CERN under their supervision. Still Tom was the protagonist of another outstanding achievement, reported at this Workshop, to which I also contributed: the employment of silica aerogel radiators in Cherenkov light imaging detectors operated in the visible range. Such studies drove the design of the HERMES and LHCb dual radiator RICHs.
3. Conclusions Tom’s influence extends beyond his achievements: his availability and open character made him the friend of everybody, a friend who could always be relied on to give good advice. His office was always open to everybody and often plenty of people from any experiment or part of the world. While I strove to maintain the utmost objectivity in this paper, I am afraid my huge appreciation of Tom makes me biased in my judgement.
25
Hence, I would like to conclude by quoting the following sentence of A. Zichichi: Tom will never be forgotten as a source of constant enthusiasm and new ideas, a passionate friend and an honest, sincere and straightforward colleague.