Relight the Candle: What happens to High Redshift Massive Quenched Galaxies

Understand

A puzzling population of extremely massive quiescent galaxies at redshifts beyond z=3 has recently been revealed by JWST and ALMA, some of them with stellar ages that show their quenching times to be as high as z=6, while their stellar masses are already above 5e10Msun.

• These extremely massive yet quenched galaxies challenge our understanding of galaxy formation at the earliest stages.
• Using the hydrodynamical cosmological simulation suite Magneticum Pathfinder, we show that such massive quenched galaxies at high redshifts can be successfully reproduced with similar number densities as observed.
• The stellar masses, sizes, formation redshifts, and star formation histories of the simulated quenched galaxies match those determined with JWST.