A Census of Sun's Ancestors and their Contributions to the Solar System Chemical Composition

In this work we compute the rates and numbers of different types of stars and phenomena (SNe, novae, white dwarfs, merging neutron stars, black holes) that contributed to the chemical composition of the Solar System. Stars die and restore the newly formed elements into the interstellar gas. This process is called "chemical evolution". In particular, we analyse the death rates of stars of all masses, dying either quiescently or explosively. These rates and total star numbers are computed in the context of a revised version of the two-infall model for the chemical evolution of the Milky Way, which reproduces fairly well the observed abundance patterns of several chemical species, as well as the global solar metallicity. We compute also the total number of stars ever born and still alive as well as the number of stars born up to the formation of the Solar System and with a mass and metallicity like the Sun. This latter number will account for all the possible existing Solar Systems which can host life in the solar vicinity. Among all the stars (from 0. 8 to 100 M_) born and died from the beginning up to the Solar System formation epoch, which contributed to its chemical composition, 93. 00\% are represented by stars dying as single white dwarfs (without interacting significantly with a companion star) and originating in the mass range 0. 8-8 M_, while 5. 24\% are neutron stars and 0. 73\% are black holes, both originating from SNe core-collapse (M>8 M_) ; 0. 64\% are Type Ia SNe and 0. 40\% are nova systems, both originating from the same mass range as the white dwarfs. The number of stars similar to the Sun born from the beginning up to the Solar System formation, with metallicity in the range 12+log (Fe/H) = 7. 50 0. 04 dex is 3. 1732 10^7, and in particular our Sun is the 2. 6092 10⁷-th star of this kind, born in the solar vicinity.