[1] Univ Calif Irvine, Dept Phys & Astron, 4129 Reines Hall, Irvine, CA 92697 USA
[2] Univ Waterloo, Dept Phys & Astron, Waterloo, ON N2L 3G1, Canada
[3] Univ Waterloo, Waterloo Ctr Astrophys, Waterloo, ON N2L 3G1, Canada
[4] Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85281 USA
[5] Univ Concepcion, Dept Ingn Informat & Ciencias Comp, Concepcion 4030000, Chile
[6] INAF, Osservatorio Astron Trieste, Via GB Tiepolo 11, I-34143 Trieste, Italy
[7] Univ Concepcion, Dept Astron, Fac Ciencias Fis & Matemat, Concepcion 4030000, Chile
[8] Univ Birmingham, Sch Phys & Astron, Birmingham B15 2TT, W Midlands, England
[9] York Univ, Dept Phys & Astron, 4700 Keele Str, Toronto, ON M3J 1P3, Canada
[10] Univ Andres Bello, Dept Ciencias Fis, Fernandez Concha 700, Las Condes 7591538, RM, Chile
[11] Ctr Estudios Fis Cosmos Aragon CEFCA, Plaza San Juan 1, E-44001 Teruel, Spain
[12] Univ Kansas, Dept Phys & Astron, 1251 Wescoe Hall Dr,Malott Room 1082, Lawrence, KS 66045 USA
[13] Univ Toulouse, Inst Rech Astrophys & Planetol, IRAP, UPS OMR,CNRS,CNES, 14 Ave E Belin, F-31400 Toulouse, France
[14] European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany
[15] INAF, Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy
[16] Univ Calif Riverside, Dept Phys & Astron, 900 Univ Ave, Riverside, CA 92521 USA
[17] Univ Arizona, Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA
[18] Univ Arizona, Dept Astron, 933 N Cherry Ave, Tucson, AZ 85721 USA