1. Physics and Astronomy Department, Louisiana State University, Baton Rouge, LA 70803, USA
2. Southwest Research Institute, 6220 Culebra Rd, San Antonio, TX 78238, USA
3. Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
4. Department of Astronomy, University of Wisconsin-Madison, 475 N. Charter St., Madison, WI 53703, USA
5. Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
6. *NASA Hubble Postdoctoral Fellow