The Nucleosynthetic signatures of the first star survivors among hyper metal-poor stars with [Fe/H] -4.5

Suda, Takuma*; Komiya, Yutaka*; Nishimura, Takanori*; Iwamoto, Nobuyuki  ; Aikawa, Masayuki*; Fujimoto, Masayuki*

The first stars in our Universe are the useful probes for the star formation history in the very early Universe. In order to identify these survivors, we should consider the effect of changing surface abundances during their long lives. The surface abundances are modified by the accretion of gas from the interstellar matter and/or the binary mass transfer. The latter can affect the abundance pattern through the evolution of primary star that experienced the internal mixing and dredge-up during thermally pulsating AGB. The top three of the iron deficient stars are reported as the candidates of the first stars. These stars have [Fe/H] -4.5 and share the common feature of large enhancement of C. We argue that these abundance patterns are testified to the evolutionary characteristics of the first stars with low- and intermediate-mass by trying to constrain the mass of primary under the assumption that they were the survivors of secondary stars in the binary system when they were born.