We recommend presentation of the lab reported radiocarbon ages along with any subsequent corrections. On request, we can provide the measured age of the background material analyzed concurrently with a particular sample. This may be especially useful in cases where the sample age is close to detection limits. The mass of submitted material required to give a target of this size varies depending on the sample type and condition. Go to Sample Submission page and view mass requirements for raw submitted samples.
Contamination introduced during preparation is of a roughly constant amount.
Fractionation effects during measurement cause a drop in the measured fraction modern for small samples, and this effect can be related to the target size. In addition, the precision of the measurement may decrease with the decreasing target size. Atoms of 14 C contained in a sample are directly counted during the AMS radiocarbon analysis, and internal statistical errors are calculated using the number of counts measured from the target. Smaller targets may provide lower counts and therefore larger statistical errors. Every sample is inspected and assigned a unique NSRL number on receipt in our laboratory.