Calculating from Sicily to CERN ROME ECFA LEP Meeting
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target. From these pictures, some course was Walter R. Nelson of The programs were run on the 350 charged current neutrino inter SLAC, presently at CERN as a visit CERN computers and the users, actions in the emulsion have been ing scientist. guided by the authors, were able to identified, and so far 60 have been The calculation of the energy solve specific problems. The experi located. This sample contains one deposited by accelerator beams, or ment was very successful. Many of event which shows all the character particles from nuclear reactors, in the programs presented at the istics of charm decay. targets or machine components is course are now available in the It includes, amongst other parti rather a complicated physical CERN computer files. They cover cles, a negative muon identified by problem. Nor is it trivial to calculate hadronic cascades, electromagnetic the EMI and a positively charged the shielding needed for radiation cascades, reactor shielding, unfold particle which, after travelling a protection of an accelerator or reac ing methods, gamma spectrum ana distance of about one millimetre, tor because of the complex geome lysis and detector efficiency and produces three charged hadrons tries of the radiation sources and the response. For further details of these which are seen in BEBC. Many inter engineering requirements for the programs, contact G.R. Stevenson pretations in terms of charmed parti shielding itself. It takes a broad or W.R. Nelson at CERN. cle decays involving at least one knowledge of the physics of particle neutral particle are possible, but the interactions with matter, of the ROME experimental evidence rules out transport of radiation through differ known strange particle decays. The ent materials, of dosimetry, etc. But ECFA LEP Meeting possibility that both this event and these calculations are obviously of On 23, 24 November the LEP Work the one seen at Fermilab are not vital importance. ing Group of the European Commit genuine is now very remote. Some very sophisticated com tee for Future Accelerators (ECFA) Like the decay seen in the Fermi puter programs have been written, held its first plenary Meeting in lab experiment, this event also and are widely used, for performing Rome. In the superb Biblioteca Valli- corresponds to a lifetime of a few calculations of that type. They can celliana, an important centre of Ital times 10-13 s, well in line with also be applied to many other differ ian culture in the baroque era, about current predictions. Meanwhile the ent problems with possible applica two hundred scientists from fifteen search continues to consolidate the tions ranging from medical physics European countries met to discuss still scanty information on charmed to high energy research, from radia the project to construct a large elec particle decays. tion dosimetry to radiobiology. tron-positron storage ring, LEP. At Erice, experts discussed with AntoninoZichichi, Chairman of the Calculating from more than forty people of different Working Group, emphasized in his Sicily to CERN scientific interests, the physics in closing speech that, besides the herent to their programs, the meth steady scientific progress toward The Ettore Majorana Centre for ods employed in the calculations and conceiving a wonderful tool for Scientific Culture, founded and di their present potential uses. The physics, the Meeting witnessed a rected by Antonino Zichichi, has programs were compared to each strong commitment from the Italian some seventy schools covering all other and related to different fields of Government to build LEP. branches of Science. The schools application either as single programs In their interventions, the two organize courses on different topics or combinations of programs. most important Italian authorities on which are normally held in Erice, a After eight days of lectures and scientific matters — Senator Mario historical village in Sicily. discussions at Erice, almost all the Pedini (Minister of Public Education) One of the schools is the 'Interna participants moved to CERN where, and the Hon. Dario Antoniozzi (Min tional School of Radiation Damage thanks to the collaboration of G.R. ister of Scientific Research) — and Protection' directed by A. Rindi Stevenson, A. Herz and the Data stated that the Italian Government of INFN, Frascati. From 25 October Handling Division, a Workshop was follows the LEP project very closely to 2 November, this school organ organized. Together with interested and hopes that its realization will not ized its second course on 'The use of people from CERN, the participants be hindered or delayed by extra- computers in health physics: calcu- saw the programs in action for the scientific matters, as has happened lational techniques in shielding and solution of problems in several fields for other European scientific enter dosimetry'. The Director of the of interest. prises in the past. For this reason. 18 CERN Courier, March 1 979 At the Rome meeting of the ECFA LEP Working Group, left to right, Jean Teillac (President of the CERN Council), Senator Mario Pedini (Italian Minister of Public Education) and Antonino Zichichi (Chairman of the Working Group). the specialized subgroups briefly reported on the most important subjects they had discussed. The enthusiasm at the Rome Meeting, the high level of the discus sions, and the support of the Italian Government are a good start on the long, hard journey of the ECFA LEP Working Group. The next rendez vous is for 4-6 April in Hamburg. NOVOSIBIRSK More studies on electron cooling At the Novosibirsk Institute of Nuclear Physics studies are continu ing on 'electron cooling' — the tech nique of reducing momentum spread in an accelerated beam which was invented at the Institute. Experiments in 1976 had revealed an unexpected effect — the cooling of a proton beam in a typical time interval of the order of 0.1 s which is Italy does not put itself forward as a interesting talk on theory, empha much faster than was anticipated candidate to host LEP on its territory sized that PETRA results will be of from the theory. and hopes that the choice of site will great value for the development of Investigations have now shown e made on the basis of maximum the LEP project. that the sharp increase in the effi operating efficiency only. The scientific level of the plenary ciency of the process is due to a The need to ensure that the largest sessions was unanimously judged marked reduction in the longitudinal possible number of European high very high. Among the contributions spread of the electron velocities energy physicists are involved in LEP were Wolfgang Schnell's report on after electrostatic acceleration and has been repeatedly stressed by the CERN LEP design, N. Bauer's to the presence of a magnetic field in Jean Teillac (President of the CERN description of the developments in the cooling section. As a result, the Council), Marcel Vivargent (Presi r.f. superconducting cavities, Gus proton interacts in the system of dent of ECFA) and by Antonino Weber's discussion on experimental concurrent electron and proton Zichichi. They have pointed out that areas, Georges Charpak's news of beams, not with a fast electron but the present structure of the ECFA breakthroughs in particle detectors with a slowly moving 'Larmor circle'. LEP Working Group is a good step and Prof. Gourdin's analysis of the This reinforces the cooling proper towards achieving the broadest con possible information that LEP will ties of the electron beam. sensus of the European community give on the basic mechanisms of the During 1977-8 electron cooling on a great scientific venture, which weak interactions. has been studied to assess the will probably dominate the European In addition to the plenary sessions, possibility of using such rapid elec scene until the year 2000. twenty specialized subgroups, into tron cooling, for example, in antipro- The Working Group heard with which the ECFA LEP Working Group ton projects. It has been demon great interest the reports from Klaus is subdivided, met in parallel ses strated experimentally that in the Steffen and Herwig Schopper on the sions and set up a detailed schedule energy range 1.5 to 85 MeV the status of PETRA and on the future for the work to be done. In the final minimum possible cooling time on plans at DESY. N. Cabibbo, in an plenary session, the Chairmen of the NAP storage ring at Novosibirsk CERN Courier, March 1979 19 .