Study on the Orbital K-electron Shakeoff in β+ Decay

Abstract

Fe K x선 -0.511 MeV 양전자 소멸 광자 -0.511 MeV 양전자 소멸 광자간의 3중 동시 측정 스픽트럼을 관측하여 β+ 붕괴에 의한 58Co K-궤도 shakeoff확률 Pk(β+ )를 결정하였다. x-선 흡수와 검출 효율 곱인자는 Fe K x선의 단일 스팩트럼 및 전자포획에서 발생된 Fe K x선과 0.8108 Mev 감마선과의 보조동시측정 스팩트럼을 각각 측정하여 이를 shakeoff확률계산에 이용하였다. 이 실험에서 얻은 핵 shakeoff 확률 Pk(β+)은 (20.61±4.18)×10-4였으며 이 값은 기존이론치보다 2내지 3배정도 큰 값이였다. 앞으로 2내지 3배의 차이를 보다 정확히 설명하기 위하여는 보다 많은 실험치와 기존이론의 수정 등이 필요하다고 본다.

The shakeoff probability for K-shell autoionization in the nuclear decay, Pk(β+), of 58Co has been determined from measurements of the Fe K X-ray- 0.511 MeV positron annihilation photon-0.511 MeV positron annihilation photon triple coincidence spectrum. The X-ray absorption and detection efficiency factor has been obtained experimentally by measuring both the Fe K X-ray single spectrum and the auxiliary coincidence spectrum of the Fe K x-rays produced in EC decay with the 0.8108 MeV gamma rays. The nuclear shakeoff probability, Pk(β+), was found to be (20.61±4.18)×10-4, which was considerably larger than the theoretical values with the factor of 2 to 3. It was suggested at this time that more experimental values of Pk(β+ ) as well as the additional theoretical work would be needed to try to explain the factor of 2 to 3 discrepancy with theory.

The shakeoff probability for K-shell autoionization in the nuclear decay, Pk(β+), of 58Co has been determined from measurements of the Fe K X-ray- 0.511 MeV positron annihilation photon-0.511 MeV positron annihilation photon triple coincidence spectrum. The X-ray absorption and detection efficiency factor has been obtained experimentally by measuring both the Fe K X-ray single spectrum and the auxiliary coincidence spectrum of the Fe K x-rays produced in EC decay with the 0.8108 MeV gamma rays. The nuclear shakeoff probability, Pk(β+), was found to be (20.61±4.18)×10-4, which was considerably larger than the theoretical values with the factor of 2 to 3. It was suggested at this time that more experimental values of Pk(β+ ) as well as the additional theoretical work would be needed to try to explain the factor of 2 to 3 discrepancy with theory.