We have studied the influence of the density of the annihilation region on the positronium continuum. A relation between the ratio 3γ/2γ and the density is explicitly given, with which one can derive directly from t...We have studied the influence of the density of the annihilation region on the positronium continuum. A relation between the ratio 3γ/2γ and the density is explicitly given, with which one can derive directly from the observed 3γ/2γ the density where the annihilation occurs. A unique solution may be found from the observed width of the 0.511 MeV line. We applied the method to three flares observed by GRS/SMM. It is shown that due to the measuring uncertainties in the 0.511 MeV line width, we cannot distinguish a chromospheric source from a coronal source, though both accurately localized. To improve the measuring accuracy of the 0.511 MeV line and the ratio 3γ/2γ will be an important step for a better understanding of the annihilation process in solar flares.展开更多
基金the National Natural Science Foundation of China.
文摘We have studied the influence of the density of the annihilation region on the positronium continuum. A relation between the ratio 3γ/2γ and the density is explicitly given, with which one can derive directly from the observed 3γ/2γ the density where the annihilation occurs. A unique solution may be found from the observed width of the 0.511 MeV line. We applied the method to three flares observed by GRS/SMM. It is shown that due to the measuring uncertainties in the 0.511 MeV line width, we cannot distinguish a chromospheric source from a coronal source, though both accurately localized. To improve the measuring accuracy of the 0.511 MeV line and the ratio 3γ/2γ will be an important step for a better understanding of the annihilation process in solar flares.
