符合多普勒展宽谱的源修正研究
Study on Source Correction of CDB Spectroscopy
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摘要: 测量了Ti，Ni，Cu，Al以及Si的符合多普勒展宽谱。对于Ni的多普勒展宽谱，采用最小二乘法拟合得出其中的源强度。给出了源修正前后湮没量子在Si中的多普勒展宽谱，讨论了源成分的影响。用高斯-抛物线模型拟合多普勒展宽谱，将多普勒展宽谱中自由电子的湮没贡献和束缚电子的湮没贡献分开，进而探讨了只对束缚电子的湮没贡献做源修正的方法。In the present work, Coincidence Doppler Broadening （CDB） measurements have been performed for five elements i.e. Ti, Ni, Cu, Al and Si. As to the CDB spectra of Ni, we obtained the annihilation fraction of positron-electron pairs in the source by least square fitting. After source correction, spectra for Si are also given to indicate the influence of source components. CDB spectra were simulated with Gauss-Parabola model to separate annihilation contribution of core electrons from outermost electrons. Furthermore, a new source correction method, i.e. source correction will be done only in the contribution of core electron, has been presented
Abstract: In the present work, Coincidence Doppler Broadening （CDB） measurements have been performed for five elements i.e. Ti, Ni, Cu, Al and Si. As to the CDB spectra of Ni, we obtained the annihilation fraction of positron-electron pairs in the source by least square fitting. After source correction, spectra for Si are also given to indicate the influence of source components. CDB spectra were simulated with Gauss-Parabola model to separate annihilation contribution of core electrons from outermost electrons. Furthermore, a new source correction method, i.e. source correction will be done only in the contribution of core electron, has been presented
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