报告题目: 0νββ-decay mechanisms, NMEs and quenching of gA 

　　报告人：Prof. Fedor Simkovic (Comenius University) 

　　时间：2019年03月20日（星期三）16:00 

　　地址：近代物理所5号楼1006会议室 

　　Abstract: 

　　The recent progress in theoretical description of the  0νββ-decay is shortly reviewed. The  0νββ-decay with the inclusion of the right-handed leptonic and hadronic currents and by assuming exchange of both light and heavy neutrinos is revisited. The question is raised whether light and heavy neutrino contributions to 0νββ-decay are experimentally distinguishable. A possible impact of the nuclear environment on the light neutrino mass mechanism of the 0νββ-decay is addressed. The present-day results of the calculation of double-beta decay nuclear matrix elements are discussed. Subject of interest are the accuracy and reliability of calculated NMEs associated with different 0νββ-decay mechanisms. A possible progress in the calculation of the double beta decay NMES within the QRPA approached is outlined and supported by the studies performed within schematic models. An impact of the quenching of the axial-vector coupling constant on double-beta decay processes is investigated and possibility to determined quenched value of gA is proposed. A connection between the 2νββ-decay and 0νββ-decay matrix elements is analyzed. The importance of charge-exchange reactions, double-charge exchange reactions and charge exchange of pion on nuclei for determining 0νββ-decay NMEs is discussed.