Recent Progress for Observation of Groundstate Twoproton Decay

Key words: 
• ground-state two-proton decay /
• proton drip line /
• BρTOF-ΔE method /
• optical time projection chamber

Abstract:  The ground-state two-proton decay is an exotic decay beyond proton drip line. It deals with the structure behavior of the proton pair at outside orbital in a proton dripline nucleus, and can be used to check the current nuclear model under extreme condition. Experimental observation of groundstate twoproton decay has been widely considered as a challenge because of very low production cross section. In this short paper, the breakthrough of searching groundstate twoproton decay is briefly reviewed, which was made more than 40 years after the early theoretical prediction was proposed.