1. Max Planck Institute for Radio Astronomy, Auf dem Hügel 69, D-53121 Bonn, Germany
2. Station de Radioastronomie de Nançay, Observatoire de Paris, CNRS/INSU, Université d’Orléans, F-18330 Nançay, France
3. Laboratoire de Physique et Chimie de l’Environnement, CNRS, 3A Avenue de la Recherche Scientifique, F-45071 Orléans Cedex 2, France
4. LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, F-92195 Meudon, France
5. Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester M13 9PL, UK
6. Department of Physics, the George Washington University, 725 21st Street NW, Washington, DC 20052, USA
7. Astronomy, Physics, and Statistics Institute of Sciences (APSIS), The George Washington University, Washington, DC 20052, USA
8. Instituto de Radioastronomía Milimétrica (IRAM), Avda. Divina Pastora 7, Local 20, E-18012 Granada, Spain
9. East Asian Observatory, 660 N. A’ohoku Place, University Park, Hilo, Hawaii 96720, USA