who predicated that black holes emit radiation and what it is called
Stephen Hawking
Hawking radiation
Hawking radiation is black-body radiation that is predicted to be released by black holes, due to quantum effects near the black hole event horizon. It is named after the physicist Stephen Hawking, who provided a theoretical argument for its existence in 1974. 
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Hawking radiation [SEP] Introduction
Hawking radiation is black-body radiation that is predicted to be released by black holes, due to quantum effects near the black hole event horizon. It is named after the physicist Stephen Hawking, who provided a theoretical argument for its existence in 1974. The requirement that black holes lose energy into the wider universe, and therefore can "evaporate", and the radiated spectrum are both a result of analysing black hole thermal equilibrium combined with extreme redshifting effects very close to the event horizon, with some consideration of quantum entanglement effects. A pair of virtual waves/particles arises just beyond the event horizon due to ordinary quantum effects.