[1] CALTECH, Cahill Ctr Astron & Astrophys, Pasadena, CA 91125 USA
[2] Ctr Astrophys Harvard & Smithsonian, 60 Garden St, Cambridge, MA 02138 USA
[3] Harvard Univ, Black Hole Initiat, 20 Garden St, Cambridge, MA 02138 USA
[4] CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA
[5] Univ Diego Portales, Fac Ingn & Ciencias, Nucleo Astron, Av Ejercito Libertador 441, Santiago, Chile
[6] Eureka Sci Inc, 2452 Delmer St,Suite 100, Oakland, CA 94602 USA
[7] Kyoto Univ, Dept Astron, Sakyo Ku, Oiwake Cho, Kyoto 6068502, Japan
[8] Korea Astron & Space Sci Inst, 776 Daedeokdae Ro, Daejeon 34055, South Korea
[9] Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England