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First Stars III
Contact:
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Poster
Title: Dust Evolution in Population III supernova remnants Author(s): Takaya Nozawa Abstract: We investigate the evolution of dust formed in Population III supernova (SNe), considering its processing through the collisions with the reverse shocks and its transport within SN remnants (SNRs), to reveal the chemical composition, size, and amount of dust injected into the early interstellar medium (ISM). We find that once dust grains inside the He core encounter the reverse shocks at 10$^3$--10$^4$ years after the SN explosions, they depict the different trajectories depending on their initial sizes $a_{\\rm ini}$, resulting in the segregated transport and destruction of dust in SNRs. For Type II SNRs expanding into the ISM with the density of $n_{\\rm H,0}=1$ cm$^{-3}$, small grains of $a_{\\rm ini} < 0.05$ $\\micron$ are destroyed by sputtering in the postshock flow, the grains with $a_{\\rm ini}=$ 0.05--0.2 $\\micron$ are trapped into the dense shell behind the forward shock, and large grains with $a_{\\rm ini} > 0.2$ $\\micron$ are ejected to the ISM withou! t decreasing their sizes significantly. The resulting size distribution of survived dust is largely deficient in small-sized grains, compared with that at the time of dust formation. The size below which dust is completely destroyed and the mass fraction of dust destroyed spans the range of 0.01--0.2 $\\micron$ and 0.2--1, respectively, depending on the gas density in the ISM and the explosion energy of SNe. Furthermore, applying the results of calculations, we discuss the abundance patterns of the second-generation stars formed in the dense shell of primordial SNRs.
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