covered by P. Jenni, who quoted test beam measurements with a spatial resolution down to 20 µm : detectors with such a reso­ lution would be used for lifetime measure­ ments at colliders. Passive Experiments New results from non-accelerator experi­ ments gave rise to animated discussions. The observed flux of energetic solar neutri­ nos seems to be significantly lower than model calculations would predict. If this is verified, the observations could be the first hint of a new physics beyond the standard From the left, W. Schmidt-Parzefall, P. model. It therefore remains Important to Professor Y. Yamaguchi, IUPAP President- Schlein and B.H. Wiik in front of the EPS measure the neutrino flux from the sun with Designate, with Dr. B. Richter, Director of stand at the 1991 LP-HEP Conference. low threshold detectors (first generation SLAC, seated in the background. detectors using a chloride solution only some extent at LEP and in heavy ion colli­ measured 8Be and 7B fluxes in the solar a 51Cr source, the measured flux was low sions at CERN-SPS and later at RICH. He neutrino spectrum). Two experiments with (< 79 Solar Neutrino Units — SNU — at underlined the importance of supercompu­ Ga as the detector medium (GALLEX and 90% confidence limits) as compared to the ter calculations at APE in and infor­ SAGE) are on the verge of obtaining data theoretically predicted rate of 132 SNU. mation on the spectroscopy of bound ha­ within the next few years. SAGE In the Finally, two new experiments are In prepara­ dronic states from LEAR and planed e + e- USSR involving 60 t of metal rather than a tion (BOREX and SNOW) for measuring the colliders. Finally, while the K meson system solution of the chloride is more compact, solar neutrino spectrum. is too complicated to distinguish between but extraction of the 71Ge produced is more The existence of a 17 KeV neutrino (page competing models for CP violation, mixing complicated. However, a background radia­ 182) gave rise to controversial discussions in the B system has opened up a new tion problem has held up calibration of which only further experiments will be able field to search for CP violation. Powerful GALLEX with a 51Cr source. It arose owing to resolve (talks by B. Barish and R. Möss- new sources of B are thus planned to the generation during storage of 68Ge by bauer). In an audience dominated by experi­ at LEP, a future e + e- collider, SSC, and at cosmic radiation. Heating the solution was mental physicists, C. Itzykson succeeded in LHC. evaluated In "hot runs" that started in explaining to a largely non-expert commu­ New accelerator techniques for high Iate-1990 and the cool down last April re­ nity the most recent trends and develop­ energy facilities, notably linear and circular sulted in a satisfactory background level. ments In abstract field theory. The impact of ep machines, for the next century were dis­ First results from the SAGE experiment on cosmology was re­ cussed by Y. Kimura. The progress that has for five months in 1990 show interesting re­ viewed by M. Turner, one of the top experts been made In detector design, mainly in the sults, which need further cross-checking. In the field. field of calorimetry, particle Identification Assuming a 100% extraction efficiency for and high resolution tracking devices, was 71Ge, which is presently being verified with W. Bartel, DESY, Hamburg

1991 EPS High Energy Physios Prize made Important contributions. We find him amongst the early advocates of Nicola Cabibbo e + e- colliding beam experiments (1961). He, together with others, proposed the The 1991 EPS High Energy Physics use of crystals for producing multi-GeV Prize, which is awarded every second year polarized bremsstrahlung photon beams. on the occasion of the Divisional confe­ In collaboration with Doniach he proved rence, was given to Professor Nicola the existence of trapped flux units in Type Cabibbo at the joint International - I superconductors and recently he has Photon and Europhysics Conference on been interested in the construction of High Energy Physics held in Geneva on parallel processors for QCD lattice calcu­ 25 July-1 August. lations — the APE Project, one of the Nicola Cabibbo, who has been Profes­ most ambitious and advanced projects in sor of Theoretical Physics at the Univer­ the field. sity of Rome since 1982 and Is at present His contributions to the theory of weak President of the INFN, received the prize interactions, which is the basis for the EPS for his "fundamental contribution to the award, is published in a paper "Unitary theory of weak interactions leading to the Symmetry and Leptonic Decays" in Phys. concept of quark mixing". He Is credited Rev. Lett. 10 (1963) 531. In those days in with a long list of honourable member­ M. Jacob, President of EPS, presenting the 1963 there were three phenomena In ships in various committees and other 1991 EPS High Energy Physics Prize to N. weak Interactions which were awaiting a bodies, amongst them the Academia Na­ Cabibbo (facing cameral. physics Interpretation : there was the ob­ zionale del Lincei In Rome. servation of strongly suppressed strange­ He started his scientific career In 1958 only one year before moving to the Univer­ ness-changing weak decays and an appa­ with a degree In physics from the Univer­ sity of Rome. He left Rome for short stays rent violation of the universality of weak sity of Rome. After positions in Rome, at the Institute for Advanced Studies, interactions, or the CVC theorem. The Frascati, CERN and LBL, Berkeley, he be­ CERN, Paris, New York, Syracuse, and he vector coupling constants derived from came a lecturer at Harvard University. In held the Enrico Fermi professorship at the 0 14 nuclear ß decay and μ decay were 1965, he obtained his first position as a University of Chicago. different. Furthermore, the observed rate professor in theoretical physics at the Uni­ The work of N. Cabibbo has covered a of β decays did not fit into any versity of L'Aquila, where he stayed for wide range of physics and everywhere he theory. Europhys. News 22 (1991) 181 N. Cabibbo in his two page long paper The 17 keV Neutrino proposed a solution to both problems. He defined an octet of unit currents J µwith Quest Continues With Improved Techniques vector and axial vector components to describe strangeness changing and stran­ Confirming the existence of a 17 keV neutrino would represent the first evidence for a geness non-changing weak decays. The physics beyond the with a breakdown of the electroweak theory predicting weights for the two components were massless neutrinos (extended models propose Dirac or Majorana terms depending on expressed as sin and cos of an angle θ, the the symmetry of the underlying theory). Evidence for the 17 keV neutrino was first reported in 1985 by John Simpson in the ß decay of 3H implanted in a Si-Li detector. Six experi­ Cabibbo angle. By comparing K + →μ+ν ments in 1985-89 looking for distortions of the ß spectra of 35S and 63Ni owing to the with π + → μ + ν he obtained a value of θ emission of the 17 keV neutrino then gave negative results. = 0.26 which is very close to the number In 1991, Simpson and Hime (working with 3H and 35S) and Hime and Jelley (14S with a given in the most recent edition of the par­ Si-Li detector) then obtained another positive result, as did groups at Berkeley (14C) and ticle data tables. This approach applied to Zagreb (71Ge) also using semiconductor detectors. G.G. Ross mentioned a preliminary hyperon decays led to predictions of bran­ report of another positive result — this time for 63Ni — at the 1991 LP-HEP Conference. ching ratios which agree within errors However, Becker et al. at Caltech using a 35S source and a double focussing spectro­ with today's measurements. The ansatz meter reported negative results. Additional negative results were presented at the LP-HEP of current mixing explains at the same Conference by Bahran and Kalbfleisch who measured ß decay in 3H with an apparatus time the difference in the vector coupling constructed of hydrogen-free material (to reduce distortion of the ß spectrum by adsorption constants measured in nuclear β decay from the walls). Curve fitting spectra showed that a < 0.4% admixture of the 17 keV and μ decay. Thus three pending problems neutrino could be excluded with a 99% confidence limit. were solved at once. Only one year later, in 1964, Gell-Mann Physics Heads Meet of the Research Councils) where physics and Zweig introduced quarks to physics division heads of national funding agencies and Gell-Mann rewrote Cabibbo's octet of Some so-called "mainstream" fields of considered mechanisms to stimulate multi- currents in terms of quark wave functions physics (fission, high energy, synchrotron national collaboration. The CEPCRC's next radiation, nuclear) have well established meeting will be hosted by Germany. organizational structures while others (neu­ In 1970, six years later, S.L. Glashow, tron scattering, high magnetic fields) are J. Iliopoulos and L. Maiani (GIM) introdu­ developing arrangements. Dr. K.H. Chang, Quantum Electronics & ced two quark doublets with pure charged Director of the Dutch physics research orga­ 2/3 state and mixed charged -1/3 states nization FOM, speaking at the meeting of Optics Division in order to correct some shortcomings of the EPS Associate Members in Cracow last The 1991 EPS Council in Zurich recom­ the theory. The weak month, stressed how the historical "inter­ mended that the Quantum Electronics Divi­ hadronic current then reads as nationalism" of physics as well as political sion (QED) consult members to see if the pressure for europeanization call for new Division's name should be changed to re­ networks and large facilities. National fun­ flect wider interests in meeting the needs of The last step brings us to the present ding agencies find planning within this members belonging to the former Optics status of the quark mixing scheme with framework increasingly difficult owing to Division. Professor Peter Knight, Chairman reductions in long-term structural invest­ of the QED Board, reports that, on the three doublets and the incorporation of CP ments being offset by special short-term Board's recommendation, the Division Bu­ violation through a non-trivial phase in the funding. Dr. Chang reported on a first siness Meeting held in September in Cabibbo-Kobayashi-Maskawa matrix : meeting, held last April in the UK, of a group Edinburgh voted unanimously to adopt the with the provisional title CEPCRC (Chair­ name "The Quantum Electronics and man of the European Physics Committees Optics Division".

W. Czaja (Ed.) Synchrotron Radiation: Selected Experiments in with the corresponding weak current Condensed Matter Physics In this volume, 10 contributions describe selected experiments in condensed matter physics with where M is the Cabibbo-Kobayashi-Mas­ synchrotron radiation, the subject matter at an kawa matrix. Considerable experimental international workshop held at the Centro effort is being devoted at present to deter­ Stefano Franscini in Ascona, Switzerland, in July mining the elements of the matrix and to 1990. The experiments concerned magnetic understanding the origin of CP violation. properties, electrical properties of clusters, liquid 1991. Approx. 168 pages. Flardcover metals and magnetic semiconductors, interface sFr. 58. - / DM 68. - The EPS High Energy Physics Prize is problems (Schottky barriers), etc. They ISBN 3-7643-2594-1 sponsored by industry. The following demonstrate the enormous impact and challenge Please send your orders to: which lies in the use of a synchrotron light source Birkhäuser Verlag AG, P.O. Box 133 firms have contributed : CH-4010 Basel / Switzerland Cray Research France (France) in many areas of solid state physics. In another Orders originating from the USA Digital Equipment Corporation Europe paper, applications of the new light source are or Canada please send to: (Switzerland) discussed in relation with the determination of Birkhäuser Boston, Inc., do Springer Verlag New crystal structures. Finally, information on the York, Inc., 44 Hartz Way, Interatom (Germany) properties and experimental possibilities of the Secaucus NJ, 07096-2491, USA Le Croy (USA) new synchrotron in Trieste are given. This Philips (The Netherlands) installation is one of the three new third Siemens AG (Germany) generation synchrotrons now under construction Birkhäuser Thomson Tubes Electroniques (France) and promises once again to enlarge the number Birkhäuser Verlag AG of possible applications. Basel · Boston · Berlin W. Bartel, DESY, Hamburg

182 Europhys. News 22 (1991)