FOREVER22: Gas and metal outflow from massive galaxies in protocluster regions
Harada, Naoki, Yajima, Hidenobu, & Abe, Makito
We study gas and metal outflow from massive galaxies in protocluster regions at z = 3 - 9 by using the results of FOREVER22 simulation projects. Our simulations contain massive haloes with Mhrsim1013 M⊙, showing high star formation rates of > 100 M⊙ yr-1 and hosting supermassive black holes with MBHrsim108 M⊙. We show that the mass loading factor (ηM) sensitively depends on the halo mass and it is ηM = 1.2 (9.2) for Mh= 1013(1011) M⊙. Once the halo mass exceeds ~ 1012.5 M⊙, the outflow velocity of the gas rapidly decreases near a virial radius, and the gas returns to a galactic centre finally as a fountain flow. Also, the metal inflow and outflow rates sensitively depend on the halo mass and redshift. At z = 3, the inflow rate becomes larger than the outflow one if Mhrsim1013.0 M⊙. Thus, we suggest that massive haloes cannot be efficient metal enrichment sources beyond virial radii that will be probed in future observations, e.g., studies of metal absorption lines with the Prime Focus Spectrograph on the Subaru telescope.