OVERVIEW & ACTIVITIES IN FINANCIAL YEAR:

JIF project

Work on the new AMS system and laboratory supported by the JIF fund (through NERC) is now well underway. The AMS instrument, which is specifically designed to give optimum performance for high precision radiocarbon measurements, and measurements close to the age limit of the technique, is ready for delivery from HVEE. The new building is under construction and due to be finished in time for the instrument to be delivered at the end of August. We expect the first results from the new instrument early in 2002.

The Unit was joined in April by Dr Tom Higham, formerly Deputy-Director of the radiocarbon laboratory at Waikato, New Zealand. He will be replacing Dr Paul Pettitt as secretary to the ORADS committee and will be looking at ways to further improve our service to archaeologists and environmental scientists as well as at a number of methodological issues.

In preparation for the new AMS system, work is underway to develop techniques for handling compound-specific samples. This includes the commissioning of a new GCCIRMS instrument which is also planned to provide a GCCAMS capability. We have also designed and are currently building as CGMS-AMS interface in conjunction with Dr Baruch Spiro (NIGL).

Following accreditation to the ISO-9002 standard last year we have received complimentary audits from the BSI. We are now developing the system towards compliance with ISO-9001:2000, the latest version of the standard. There have been several enhancements to our Quality Assurance system.

Five members of the laboratory attended the Jerusalem Radiocarbon conference and presented five papers (including the keynote address by Robert Hedges) and two posters.

OVERVIEW & SCIENCE SUPPORTED IN FY:

1. Neolithic Chambered Tombs (University of Cardiff; Cambridge University; and others)
This topic includes several projects in which a closer examination is being made of the chronology of chambered tombs. This research is being combined with dietary analysis using stable isotopic data, and with physical anthropology. Highlights include showing a remarkably early date for the unusual Coldrum Tomb in Kent, and interesting isotopic systematics at Prisse la Charriere (W. France) which suggest both the consumption of freshwater fish and the occurrence of a radiocarbon reservoir effect. The implications are still being studied.

2. Dating the lowest levels of Catal Huyuk
Dating from new excavations of this outstandingly important Neolithic site has provided the following:- Start dates for one of the most complex sites in the region; chronological relationships between the various parts of the excavated site: a temporal comparison to the Levantine sequence as a whole: an understanding of the rate of adoption of pottery and domesticates in the region.

3. Extinction of Megafauna in Europe (University College London)
This large project (350 dates over three years, NERC ref. GR3/12599; dates funded as supplement to facility block-allocation) is now fully under way, with half the samples collected. It aims to document the latest reported occurrences of now extinct large mammals (mammoths, rhinos, giant deer, etc) in Europe during Oxygen Isotope Stages 3 and 2. The project is challenging because the samples are small, from museums and often conserved, often contain little collagen, and can be at the date range limit for radiocarbon. Results so far have served to remove many puzzling features on unusually late fauna (usually they were previously mis-dated); there is a suggestion of late survival of Stephanorhinus and Palaeoloxodon, while the southernmost limits of Mammuthus and Megaloceros are now being well documented.

FUTURE DEVELOPMENTS/STRATEGIC FORWARD LOOK All future developments are planned around the advantages that will be afforded by the new AMS system to be delivered in the summer. These should be: Improved efficiency (reduced turn-around times and higher throughput) Improved precision (allowing us to work towards higher precision dating - as the pre-treatment techniques develop) Improved background (allowing the reliable dating of older material, and perhaps more importantly the enhanced ability to study methodological issues arising with very old samples). Our strategy for good stewardship of these resources has been addressed in our paper presented to the AMS strategy group meeting in November 2000. Our research agenda aims to study the 'Evolution of the Natural Environment' and encompasses Terrestrial (including Archaeological), Atmospheric and Oceanographic science. This is being pursued through research collaborations (e.g. on compound specific dating of lipids, atmospheric pollutant and tracer work and our own work on amino acids, chitin-glucosamine and cellulose-glucose) and through the service provision of ORADS. We see compound specific work as being a key area in further development of the methodology. This implies the ability to efficiently deal with samples right down to the microgram level. We are now constructing (a) an on-line gas feed to the ion source for the measurement of extremely small samples, and (b) a system for collecting CO2 samples resulting from GC-combustion systems (as used in GC-C-IRMS). Please refer to our strategy paper for further details.