Reply to "Comment on 'La-Ce-Ce nuclear cosmochronometer of supernova neutrino process'"

Hayakawa, Takehito; Shizuma, Toshiyuki; Kajino, Toshitaka*; Ogawa, Kengo*; Nakada, Hitoshi*

We have proposed a new nuclear cosmochronometer La(T=102 Gyr)-Ce-Ce for measuring the time elapsed from a supernova process episode. La is synthesized by the process. If a 1 excited state exists at energy lower than 72 keV, the 1 state may be a unstable isomer and La synthesized by the process is destroyed via the isomer. Recently, Byelikov et al. have measured Gamow-Teller strength distributions in La. It has been presented that this experiment shows that the existence of a low-energy 1 state in La is extremely unlikely. Our calculated result is consistent with their result and we conclude that there is no evidence that suggests the existence of the 1 isomer in La.