eii'iSôorez. INIS-mf—14563 PAUL SCHERRER INSTITUT • * > PSI • Annual Report 1994 / Annex NIA Condensed Matter Research using Large Facilities PAUL SCHERRER INSTITUT JUS Annual Report 1994 Annex F3A PSI Condensed Matter Research and Material Sciences Edited by: U. Baltensperger, R Lorenzen Cover: A general view of the SINQ facility towards the end of 1994. Fore-word The project spallation neutrons source (SINQ) has been its experimental infrastructure. Furthermore some of the presented in its entirety in the report of last year. - I hence piled up data could find its way from the desks into the refrain from presenting the facility likewise, but rather journals. The publication list of 1994 might be evidence for show a set of pictures to give an impression about the this effect. typical activities during 1994. These should lead us towards the final push in 1995. PSI urgently needs the The Laboratory for Astrophysics was responsible for neutrons for research. This is also put into evidence by the sending a (small) part of PSI into space orbit. The award of the Nobel prize for Physics in 1994 to Bert radiation environmental monitor (REM) has been launched Brockhouse and Cliff Shull for this pioneering research into an geostationary orbit by an "Ariane" rocket from with neutron beams in the period from 1947 to 1960. By ESA. Somewhat later (mid September) a second monitor now there is general agreement that the experimental was installed by an astronaut on the Russian MIR-station. method of neutron scattering is still going to be one of the The project work on the XMM- and EUVITA-systems most powerful tool for the investigation of condensed hopefully providing us once with the data in the spectral matter in the most general sense. region of UV and soft X-rays proceeds well and the development of high resolution X-ray detectors shows As a contribution of the academic training of young some progress. scientists PSI organised its 2nd Summer School on Neutron Scattering in Zuoz. The general subject was What concerns the prospective study for a high luminosity "Neutron Scattering From Hydrogen in Materials". A taste positron source, we hope to report about an extraordinary of the success of this school may be obtained by having a performance next year. Investigation of nanostructured glance through the proceedings . materials, nanosized superconducting filaments, fractal dimensions of aerosols, interaction of cluster beams as well The Tandem van der Graaff at the Laboratory of as the properties of multilayers systems form a class of Ionbeam-Physics served its duty as a working horse for activities in various laboratories of our research accelerator mass spectroscopy for various institutions for department. I hope that they might once condense to a nearly 2500 hours; about 500 hours have been allotted to common (more coherent) task for the whole department. materials science and developments of new detection technique. One of the highlights from this laboratory is Also in the year 1994 two of our collaborators received probably the successful development and experimental awards. I have the pleasure to congratulate Dr. A. Türler exploitation of various cluster beams. These open up new from the Laboratory of radiochemistry for the respected perspectives in the study of material defects. "Fritz Strassmann"-price from the "Gesellschaft Deutscher Chemiker" and Dr. P. Allenspach from the Laboratory of The "aerosols" are a major and central topic in the neutron scattering for the 1994 ETH-TIT award (Tokyo Laboratory of Radiochemistry. Using appropriate Institute of Technology). Finally I would like to express my radionuclei the aerosols are a research object by their own. appreciation to all the collaborators within and outside the On the other hand they are used as experimental tools for department, who contribute with their competence to our the environmental research program of the laboratory. common cause. Finally they serve in a similar way as vehicles in the gas- jet technique for the fundamental research activities on superheavy elements. Hence a specialised know-how is established which finds its application in rather diverse fields of scientific activities. As already indicated - with the reactor "Saphir" shut down and SINQ not yet operational - no neutrons were available W.E. Fischer on site at PSI. Moreover, also the ILL-reactor was still in HeadofDept. F3A its shut down phase. Hence the Laboratory for Neutron Scattering had to seek the neutrons elsewhere, as e.g. at HMI (Berlin), ISIS (Rutherford Appleton) or ORPHEE (Saclay) and Ris0. We are grateful for the hospitality given by these institutes. Obviously the staff members invested also much time into the development of the new instrumentation of SINQ and "Neutron Scattering from Hydrogen in Materials", ISBN: 981-02-1874-5. World Scientific Publishing Co. Pte. Ltd. P.O. Box 128, Farrer Road. Singapore 9128 I TABLE OF CONTENTS PROJECTS: • SINQ SINQ in 1994 - Progress in Pictures 2 • Positron Project 306 The PSI Positron Beam and its Potential of Performance Up-Grading 8 High Intensity Slow-Positron Beams Interacting with Matter 10 • Nanostructured Materials Vapour-Phase Synthesis of Nanostructured Materials 13 Magnetic Correlations and Microstructure of Nanostructured Fe and Ni, Studied by Small Angel Neutron Scattering 14 Nanostructured Ni3Al Obtained by Inert Gas Condensation 15 Nanocomposite Si3N4-SiC, Characterized by Tern and Sans 16 • Studies 50 Hz - Alternating Current Losses in NbTi Multifilament Superconductors with Nano-Size Filaments 17 AC Losses in Superconducting High-Tc BI-223/Ag Multifilament Tapes 19 LABORATORY FOR ION BEAM PHYSICS The PSI/ETH Tandem Accelerator Facility 22 Evidence for Enhanced 10Be Deposition in Mediterranean Sediments 35 Kyr BP 23 Scavenging of 10Be at Ocean Margins 24 Increased Weddell Sea Margin Radionuclide Deposition during Deglacial Periods: High Biological Productivity of Sediment Redistribution? 25 10Be and Barium: Two Tracers for Paleoproductivity Variations in the Angola Basin 26 Ambiguity of 10Be Flux in Sediments from Ontong Java Plateau: The Geomagnetic Dipole Field Versus Paleoproductivity 27 The C02 Exchange Rate for Pyramid Lake 28 Radiocarbon Budget in Soppensee 29 Dating of Rock Varnish 30 Radiocarbon Age of the Laacher See Tephra: 11,230+40 BP 31 Radiocarbon and Absolute Dating of the Younger Dryas 32 Surface Exposure Dating of a Younger Dryas Moraine in the Swiss Alps Using 10Be and MA1 33 Exposure Ages of greater than CA. 5 Million Years for the Upper Surface at Table Mountain and the Sirius Group at MT. Fleming, Antarctica 34 AMS Measurement of 10Be, 14C and MA1 in Stony Meteorites from Sahara 35 Characterisation of the Groundwater Circulation in Tectonic Active Areas of North Western Anatolia/Turkey 38 36C1 Determinations of the Groundwater in London Chalk Aquifer 39 Role of Renal Physiology in Aluminum Toxicokinetics 40 Tissue Accumulation of Orally Administered MA1 in Intact and Uremic Rats 41 Projectile X-Ray Detection: Application and Limits 42 Production of MeV Cluster Ion Beams 43 Defect Production in Silicon Caused by High Electronic Energy Loss of MeV Carbon Clusters 44 Interaction between the Fragment Tracks of an MeV Germanium Cluster Impact on Silicon 45 II Application of Focused Ion Beams for the Fabrication of Microlenscs 46 Investigation of Defects in Semiconductors Induced by Focused Ion Beams 47 Upgrade of the FIB System: Imaging in Transmission Mode 48 LABORATORY FOR RADIO- AND ENVIRONMENTAL CHEMISTRY « Trace Elements The Uptake of As, Br and I into Spruce Needles 50 Trace Elements in Norway Spruce from a Maritime Site 52 Soil-Derived Deposits on the Surface of Spruce Needles 53 The Sorption Properties of the Soil as a Factor in the Transfer of Rb and Cs to Norway Spruce 55 • Aerosol and Analytical Chemistry In-Cloud Scavenging of Aerosol Particles by Cloud Droplets and Ice Crystals at Jungfraujoch 57 Physical Processes Affecting the Chemical Composition of Precipitation at the High-Alpine Site Jungfraujoch 58 210Pb in Aerosol and Snow Samples of Jungfraujoch ; 59 Observation and Simulation of Air Pollution at Jungfraujoch: A Joint ALPTRAC/EUMAC Case Study 60 Ice Core Drilling on Monte Rosa 61 Ion Chromatographic Cation Trace Analysis of Snow and Firn Samples from High-Alpine Sites 62 Lead Concentrations and Isotopic Ratios in Recent Snow Samples from High Alpine Sites 64 Stable Isotope Analysis of Sulfur, Nitrogen and Carbon in Snow Samples from Jungfraujoch 65 32Si Concentrations in Fresh Snow Samples from Jungfraujoch 66 Cross Section Measurements of the Reaction 14,15N(p,X)7Be Using the Gas Target Technique 67 13 Selective Catalytic Reduction of NO by NH3 over Chromia Using Positron-Emitting N 68 Heterogeneous Chemical Processing of 13N02 at Zero Concentration by Monodispcrscd Carbon Aerosols 69 13 Tracing Uptake of N02-N by Spruce Needles with N02 70 Growth of Combustion Aerosols at High Relative Humidity 71 Dimethyl Sulfide, Methane Sulfonic Acid and Physico-Chemical Aerosol Properties in Atlantic Air from the United Kingdom to Hallcy Bay 72 Ingcstivc Behaviour of Steers Grazing a Tropical Grass/Legume and a Grass alone Pasture under Contrasting Stocking Rate 73 « Heavy Elements Investigation of Tungsten Oxychloridcs via Mass Spectrometry 74 Can a Q-Value Model Describe Fission Yields? 75 Radius-Volatility Correlation of the Tetrachlorides of Ti, Zr, Hf, 104, Th and U 76 Estimated Standard Enthalpies of Gaseous 104 and 105 and Stability and Volatilit of their Chlorides and Oxychloridcs... 77 Estimated