论文标题
通过GEANT4确定的γ光谱分析确定的发射PS的绝对分数
Absolute fraction of emitted Ps determined by GEANT4 supported analysis of gamma spectra
论文作者
论文摘要
通常假定，从高温下从锗单晶表面发出的正电子（PS）的比例通常在零正电子植入能量下接近统一。但是，在实验中，绝对PS分数的确定并不是直接的，因为记录了以$ 100 \，\％$ ps形成的参考频谱的要求。我们使用geant4模拟的检测器对$2γ$和$3γ$辐射源的响应模仿frm II的Nepomuc的（偶然）多普勒百老汇光谱仪内部的PS Positron和PS niHIhitation，以便得出从GE（100）GE（100）目标加热关闭的PS分数的可靠值。通过拟合模拟光谱对测量光谱进行分析显示$（72 \，\ pm {4}）\，\％$最大PS组的绝对值，与$ 100 \，\％$假设相矛盾。
The fraction of positronium (Ps) emitted from a surface of a germanium single crystal at high temperature is usually assumed to approach unity at zero positron implantation energy. In the experiment, however, the determination of the absolute Ps fraction is not straight forward since recording a reference spectrum with $100\,\%$ Ps formation remains demanding. We use GEANT4-simulated detector responses to $2γ$ and $3γ$ radiation sources mimicking positron and Ps annihilation inside the (coincidence) Doppler-broadening spectrometer at NEPOMUC, FRM II, in order to derive a reliable value for the Ps fraction reemitted from a Ge(100) target heated close to its melting point. Analysis of the measured spectra by fitting the simulated spectra shows an absolute value of $(72\,\pm{4})\,\%$ maximum Ps formation, contradicting the $100\,\%$ assumption.
