摘要
加速器质谱１４Ｃ测量误差的主要来源是１４Ｃ计数的统计误差与束流传输的不稳定性。对高精度测量还要考虑束流积分仪中ＩＦＣ的非线性及离子源中弹坑效应引起的时变分馏。为得到高精度的样品年代数据，除提高１４Ｃ测量精度外，还要用系列样品进行高精度的树轮校正，并采取必要措施保证测量结果的可靠性。
The precision and accuracy of AMS 14 C dating have been studied.The main source of error comes from the statistical error of 14 C counting and the instabitity of beam transmission effeciency.For high precision measurement the non linearity error of current frequency conversion in beam current integrator and the time dependent fractionation introduced by crater effect in ion source should also be considered.To meet the requirement of Xia Shang Zhou Chronology Project,PKUAMS upgrade was carried out.The stability of power supplies and the system vacuum were improved.The ion source has been replaced by a new one with better performance and reliability.With new data acquisition system the precision of lived time readout could reach 0.005%￣0 01%. In order to obtain high precision age data,it is necessary not only to improve the precision of 14 C measurements,but also to use the series samples in dendrological calibration by wiggle matching method based on the Bayesian approach.The reliability of sample age depends on suitable sample selection and preparation,as well as the elimination of systematic error in measurement.
出处
《北京大学学报（自然科学版）》
CAS
CSCD
北大核心
1998年第2期201-206,共6页
Acta Scientiarum Naturalium Universitatis Pekinensis
基金
国家自然科学基金
关键词
加速器质谱
精度
地质年代
测定
碳同位素
accelerator mass spectrometry(AMS)
14 C dating
high precision
