tokens: Support comes from the ERC Synergy Grant “BlackHoleCam – Imaging the Event Horizon of Black Holes” (Grant 610058). M.P. acknowledges support by the Spanish “Ministerio de Economía y Competitividad” grants AYA2013-48226-C3-2-P and AYA2015-66899-P. Z.Y. acknowledges support from an Alexander von Humboldt Fellowship. E.R. acknowledges support from the grants AYA-2012-38491-C02-01, AYA2015-63939-C2-2-P, and PROMETEOII/2014/057. C.M.F. wants to thank Walter Alef and Helge Rottmann for support during the computation on the MPIfR cluster and Mariafelicia De Laurentis and Hector Olivares for fruitful discussion and helpful comments to the manuscript.
ner_tags: O O O O B-Organization B-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant I-Grant B-Grant I-Grant B-Person O O O O B-Location B-Organization I-Organization I-Organization I-Organization I-Organization B-Grant I-Grant O B-Grant B-Person O O O O B-Fellowship I-Fellowship I-Fellowship I-Fellowship B-Person O O O O B-Grant I-Grant B-Grant O B-Grant B-Person O O O B-Person I-Person O B-Person I-Person O O O O O O O B-ComputingFacility I-ComputingFacility O B-Person I-Person I-Person O B-Person I-Person O O O O O O O O O