[1] Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03784 USA
[2] Johns Hopkins Univ, Ctr Astrophys Sci, 3400 N Charles St, Baltimore, MD 21218 USA
[3] Australian Natl Univ, Res Sch Astron & Astrophys, Canberra, ACT 2611, Australia
[4] Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA
[5] Univ Concepcion, Dept Astron, Casilla 160-C, Concepcion, Chile
[6] Univ La Serena, Inst Invest Multidisciplinario Ciencia & Tecnol, Ave Raul Bitran S-N, La Serena, Chile
[7] Univ La Serena, Dept Astron, Fac Ciencias, Av Juan Cisternas 1200, La Serena 1700000, Chile
[8] Amer Univ, Dept Phys, Washington, DC 20016 USA
[9] Univ Nacl Cordoba, Observ Astron, Laprida 854, RA-5000 Cordoba, Argentina
[10] Florida Atlantic Univ, 777 Glades Rd,SE-43,Room 256, Boca Raton, FL 33431 USA
[11] INAF Osservatotio Astron Roma, Via Frascati 33, I-00078 Rome, Italy
[12] Korea Astron & Space Sci Inst, Daejeon 305348, South Korea
[13] Univ Florida, Dept Astron, 211 Bryant Space Sci Ctr, Gainesville, FL 32611 USA