XA04N2783 ANSTO/ANP - PR 95 INDC(AUL - 44G fNIS-XA-N--171 AUSTRALIAN NUCLEAR SCIENCE TECHNOLOGY ORGANISATION PROGRESS REPORT OF APPLICATIONS OF NUCLEAR PHYSICS JULY 1994 - JUNE 1995 NOT FOR PUBLICATION (SUCCESSOR VOLUME TO ANSTO/ANP - PR 94) ANSTO/ANP - PR 95 INDC(AUL - 44G AUSTRALIAN NUCLEAR SCIENCE TECHNOLOGY ORGANISATION PROGRESS REPORT OF APPLICATIONS OF NUCLEAR PHYSICS JULY 1994 - JUNE 1995 NOT FOR PUBLICATION (SUCCESSOR VOLUME TO ANSTO/ANP - PR 94) APPLICATIONS OF NUCLEAR PYSICS PROGRESS REPORT - JULY 1994-JUNE 1995 PROGRAM OVERVIEW The objectives of the Applications of Nuclear Physics Program Area are: The development and promotion of research programs on national nclear science facilities such as charged particle accelerators and neutron beam instruments thereby encouraging strategic research i nclear science and technology at ANSTO, in tertiary institutions and industrial researchand development laboratories. Participationin and management of Australian se of international neutron scattering, nchrotron radiation and high energy physics facilities to assist graduate training in the niversities and to foster Astralian benefits ,from developments in high technology. The aintenance of epertise in fiindamental nuclear and atomic processes relevant to nclear science and technology including neutron physics, ion interactions, radiation standards,dosimerry and laser enrichment. Expansion of the se of accelerator mass spectrometn7 both ationally and iternationally to make ajor contributionsin the nderstanding and reinediation ofsevere evironmental problems sch as the greenhouse effe c t. The application of charged particle beams and ionising radiation to idustrial.biological ad environmental problems. The eploitation of neutron scattering techniques i the development of new materials, drugs, biological substances and complex chemicals. The research activities of the Applications of Nuclear Physics Pro-ram Area are organised into several arge projects: Accelerator Applications Accelerator TMass Spectrometry Neutron Scattering International Science incorporating High Energy Physics and Synchrotron Radiation Research) Radiation Technology and Standards In addition, there were a number of other supporfing projects. An important aspect of the activities of the Program Area, as will be clear from the objectives listed above, is the development and improvement of the larger experimental facilities within the Program Area. Considerable progress has been made in the development of the Tandem accelerator in the current year. The new HVEC Model 846 Ion Source was installed on the 90' injection line of the Tandem. Full computer control of this ion source is now possible. The HVEC Model 860 ion source previously in this position was moved to the right 33' port of the 45 degree injection magnet. The optics for a He ion source have been studied and an Alphatross ion source with an 80 kV injector system has been ordered. This will be located on the left 33' port of the 45 degree injection magnet. Considerable progress has also been made with the beamline facilities. The "'C AMS was improved with better alignment and modification of the detector system. The electrostatic analyser beamline, used for all other AMS measurements, is now fully operational. A new electrostatic beamline, to be located on the O' port of the high energy analyser magnet, has been designed to permit AMS measurements of elements to A = 250 and the beamline is expected to be installed in 1996. Several electrostatic quadrupole magnets and a high voltage large radius electrostatic analyser is on order. Improvement in the neutron scattering facilities and ancillary equipment has continued during the year. The new four-circle diffractometer was installed on 2TanA in the second half of 1994. An additional 9 detector channels (total number now 24) have been added to the Medium Resolution Powder Diffractometer (MRPD), and good i quality powder pattens can now be collected in a few minutes. A major effort continues towards the installation of AUSANS. The development and construction of the position-sensitive neutron detector is the most challenging aspect of this project. Design chances have been made to overcome the failures which occurred during the first trials and the detector is now beina re-assembled for a second trial soon. Polarising supermirrors which will improve the beam intensity and polarisation of the long wavelength polarisation instrument (Longpol) have been developed (with Hahn Meitner) and are now under construction. A sample changer for use on either powder instrument has been designed, constructed and is now in use, and both high temperature furnaces have been brought under computer control. These improvements have led to a substantial increase in both the quality and quantity of data obtained. This has led to the use of neutron sattering for new experiments previously considered to be in the too hard basket. In situ studies of structural and inaarietic phase changes are becoming routine, and kinetic information can now be derived. The Phase 11 monochromator for the Australian National Bearriline Facility at the Photon Factory was installed during the current year. The monochromator features sagittal focussing and fixed height exit for the monochromator. Accelerator Based Ion Beam Analysis The development of ion beam analysis facilities on the Tandem accelerator has created new opportunities for their application to surface and interface characterisation studies. The high energy, heavy ions generated by the Tandem make it suitable for heavv ion time-of-fli-ht recoil spectrometry which is now in routine use. Studies performed recently with this technique include the analysis of thin etal nitride films, modification of ion implanted high temperature superconductors and depth profiling of metal germanide layers. In addition. time-of- fIiQht recoil spectrometry has provided the basis for an Australian-Swedish collaboration on the characterisation of several semiconductor materials such as MOCVD grown aluminium -allium arsenide and indium phosphide thin films. Proaress has also been made on the proposed heavy ion microprobe on the Tandem with the completion of initial ion beam optics calculations. These examined several novel configurations and arrived at a design capable of meeting acceptable performance specifications. The aforementioned research on te Tndem has been complemented by extensive usa.ge of the older 3 MV Van de 6raaff accelerator. This facility is now used primarily for routine analysis by both ANSTO scientists and external researchers from Australian universities supported by the Australian Institute of Nuclear Scionce and Engineering, ANSTO has continued to play a major role in fine particle aerosol sampling and analysis in Australia. Support for this research as come from industrial groups and local cuncil bodies who are interested in the distribution and composition of aerosols in a particular rgion or from research bodies who are examining the relationship between airborne fine particles and espiratory conditions such as asthrria. In addition, an investigation of fine particle source reconciliation has been carried out under a ,rant from he NSW Environmental Trust. The combination of ANSTO's extensive database of elemental compositions of fine particles with eteorological data has permitted the estimation of source contributions to the total fine particle mass sampled in urban and rural environments. Participation in international programs which foster the development of nuclear techniques and their application to aerosol pollution studies has also been aintained under the auspices of the Cooperative Research Pro-rams of the International Atomic Energy Agency or through direct interaction with environmental agencies and universities worldwide. The strength of the current ANSTO program is highlighted by a recent C IC collaboration with the National University of Singapore and the Singapore inistry of the Environment. ANSTO contributed expertise and two aerosol samplers to this interaction which will utilise the proton microprobe in the University's Physics Department to obtain elemental maps of individual aerosol particles. Accelerator Mass Spectrometry The aim of the AMS project is to promote advanced research programs in Quaternary science, global climate chance, biomedicine and nuclear safeauards, based on the use of Ion--lived radioisotopes. The requirements of these programs necessitate continuous technical developments to enhance precision, sensitivity and throughput and to expand the range of measurable radioisotopes. The AMS project has developed in the past five years, a comprehensive AMS spectrometer based on the ANTARES accelerator and a clean laboratory for processing natural samples and prepare suitable tar-ets for the accelerator. The AMS spectrometer combines capabilities to measure a range of radioisotopes with hgh precision and high throughput. The Iona-lived radioisotopes 14 C, C 0 C C, 26AI, 36CI and "'I can be currently measured, with '13e and actinides under development. Improved precision ii for 14C, to 0.5% has been achieved with the commissioning of a 59 sample ion source coupled with automated data acquisition. In the two years since becoming operational more than 1500 unknown samples have been measured of which approximately 85% were 14C. Neutron Scattering A number of projects pursued in collaboration with Advanced Materials staff have been progressing well. In addition to recording data from the more intractable