Relying on telescopes in Arizona and Hawaii (which would eventually be part of the EHT), they tried to get observations of Sagittarius A * at higher angular resolutions than had been possible before, but failed to detect the signals they expected to see in the immediate vicinity of the black hole. (discovermagazine.com)
In order for an accretion disk to be continuously shining, a fueling source, i.e. a companion star, must be in the close vicinity of a black hole. (eaobservatory.org)
For example, he and his collaborators are currently trying to calculate the intensity of electromagnetic radiation emanating from the vicinity of a black hole. (discovermagazine.com)