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تسجيل مستخدم جديدThe properties of the first galaxies in the BLUETIDES simulation
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We employ the very large cosmological hydrodynamical simulation BLUETIDES to investigate the predicted properties of the galaxy population during the epoch of reionisation ($z>8$). BLUETIDES has a resolution and volume ($(400/happrox 577)^{3},{rm cMpc^3}$) providing a population of galaxies which is well matched to depth and area of current observational surveys targeting the high-redshift Universe. At $z=8$ BLUETIDES includes almost 160,000 galaxies with stellar masses $>10^{8},{rm M_{odot}}$. The population of galaxies predicted by BLUETIDES closely matches observational constraints on both the galaxy stellar mass function and far-UV ($150,{rm nm}$) luminosity function. Galaxies in BLUETIDES are characterised by rapidly increasing star formation histories. Specific star formation rates decrease with redshift though remain largely insensitive to stellar mass. As a result of the enhanced surface density of metals more massive galaxies are predicted to have higher dust attenuation resulting in a significant steepening of the observed far-UV luminosity function at high luminosities. The contribution of active SMBHs to the UV luminosities of galaxies with stellar masses $10^{9-10},{rm M_{odot}}$ is around $3%$ on average. Approximately $25%$ of galaxies with $M_{*}approx 10^{10},{rm M_{odot}}$ are predicted to have active SMBH which contribute $>10%$ of the total UV luminosity.
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