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تسجيل مستخدم جديدDiscrimination of heavy elements originating from Pop III stars in z = 3 intergalactic medium
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We investigate the distribution of metals in the cosmological volume at $zsim3$, in particular, provided by massive population III (Pop III) stars using a cosmological $N$-body simulation in which a model of Pop III star formation is implemented. Owing to the simulation, we can choose minihaloes where Pop III star formation occurs at $z>10$ and obtain the spatial distribution of the metals at lower-redshifts. To evaluate the amount of heavy elements provided by Pop III stars, we consider metal yield of pair-instability or core-collapse supernovae (SNe) explosions of massive stars. By comparing our results to the Illustris-1 simulation, we find that heavy elements provided by Pop III stars often dominate those from galaxies in low density regions. The median value of the volume averaged metallicity is $Zsim 10^{-4.5 - -2} Z_{odot}$ at the regions. Spectroscopic observations with the next generation telescopes are expected to detect the metals imprinted on quasar spectra.
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