[1] New York Univ Abu Dhabi, Phys Dept, POB 129188, Abu Dhabi, U Arab Emirates
[2] New York Univ, Ctr Astro Particle & Planetary Phys CAP3, POB 129188, Abu Dhabi, U Arab Emirates
[3] Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany
[4] Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany
[5] Queens Univ, Dept Phys Engn Phys & Astron, Kingston, ON K7L 3N6, Canada
[6] Zhejiang Univ, Zhejiang Univ Purple Mt Observ Joint Res Ctr Astr, Hangzhou 310027, Peoples R China