Radiocarbon Dates From the Oxford Ams System: Archaeometry Datelist 23

This twenty-third list of accelerator dates consists mainly of material dated since the beginning of 1994.but includes a number of measurements made earlier in the dating programme.The dates have been achieved by the methods described in Law and Hedges (1989), Hedges et uI.(1989; 1992).Determinations with OxA numbers greater than 2095 were measured on the CO, gas ion-source (Bronk and Hedges 1989) rather than on the previous iron-graphite system.In accordance with international radiocarbon convention all dates are expressed in radiocarbon years before A D 1950 (years BP) using the half-life of 5568 years.Errors are quoted as one standard deviation and are based on an assessment of all the contributions to the error in the laboratory isotope ratio measurement.Natural fractionation of carbon isotopes is accounted for by measuring the 6C values relative to PDB (with errors of approximately 0.3'%~).All combining procedures and significance tests are based on Ward and Wilson (1978).