1. Max Planck Institute for Astrophysics , Karl-Schwarzschild-Strasse 1, Garching 85748, Germany
2. Physics and Astronomy Department, Johns Hopkins University , Baltimore, MD 21218, USA
3. Department of Physics and Astronomy, Stony Brook University , Stony Brook, NY 11794-3800, USA
4. Center for Computational Astrophysics, Flatiron Institute , New York, NY 10010, USA
5. Anton Pannekoek Institute for Astronomy, University of Amsterdam , Science Park 904, 1098XH Amsterdam, The Netherlands