The acronym GEMS stands for Growth of Early Massive Seeds.
This radiation-hydrodynamic code was built from scratch to investigate the formation, growth, cosmological evolution and observability of the first black holes formed in the Universe: the first gems to enlighten the Universe.
The code is able to accurately describe the accretion process onto a black hole seed of a given initial mass, providing detailed information of the physical properties of the accreted gas and computing the outgoing spectrum of the source, emerging from its host halo.
With this very powerful tool, we were able to propose that CR7 and two objects in the CANDELS/GOODS-S field may be identified as Direct Collapse Black Holes.
This video shows the time evolution of the spectrum emerging from the host halo of a direct collapse black hole, computed with GEMS.
For further information about the code, please contact me!