The first six months of the Advanced LIGO's and Advanced Virgo's third observing run with GRANDMA
Bertin, E.; Kann, D. A.; Berthier, J.; Cordier, B.; Leroy, N.; Coleiro, A.; Cailleau, A.; Klotz, A.; Peyrot, A.; Thöne, C. C.; de Ugarte Postigo, A.; Mo, J.; Basa, S.; Christensen, N.; Coughlin, M. W.; Gendre, B.; Hello, P.; Howell, E. J.; Wang, C. J.; Burkhonov, O.; Simon, A.; Vachier, F.; Sadibekova, T.; Blažek, M.; Bai, J. M.; Corre, D.; Moore, J.; Zhang, J. C.; Wang, X. F.; Turpin, D.; Noysena, K.; Boër, M.; Antier, S.; Teng, J. P.; Thierry, P.; Delattre, C.; Barynova, K.; Lachaud, C.; Marchal-Duval, G.; Zhang, J. J.; Han, X.; Coward, D.; Baransky, A.; Inasaridze, R.; Vasylenko, V.; Dietrich, T.; Ducoin, J. -G.; Stachie, C.; Li, W. X.; Zhang, X. H.; Agayeva, S.; Aivazyan, V.; Alishov, S.; Arbouch, E.; Beradze, S.; Burrell, A.; Chabert, B.; Chen, J. C.; Crisp, H.; Duverne, P. -A.; Eymar, L.; Fock-Hang, P.; Ismailov, N.; Kapanadze, G.; Kochiashvili, N.; Le Van Su, A.; Lin, W. L.; Lognone, P.; Marron, R.; Natsvlishvili, R.; Perrigault, S.; Samadov, D.; Tillayev, Y.; Vardosanidze, M.; Vidadi, Z.; Wei, J.; Yan, S. Y.
France, Azerbaijan, Georgia, Ukraine, China, Spain, Uzbekistan, Australia, United States, Netherlands
Abstract
We present the Global Rapid Advanced Network Devoted to the Multi-messenger Addicts (GRANDMA). The network consists of 21 telescopes with both photometric and spectroscopic facilities. They are connected together thanks to a dedicated infrastructure. The network aims at coordinating the observations of large sky position estimates of transient events to enhance their follow-up and reduce the delay between the initial detection and optical confirmation. The GRANDMA programme mainly focuses on follow-up of gravitational-wave alerts to find and characterize the electromagnetic counterpart during the third observational campaign of the Advanced LIGO and Advanced Virgo detectors. But it allows for follow-up of any transient alerts involving neutrinos or gamma-ray bursts, even those with poor spatial localization. We present the different facilities, tools, and methods we developed for this network and show its efficiency using observations of LIGO/Virgo S190425z, a binary neutron star merger candidate. We furthermore report on all GRANDMA follow-up observations performed during the first six months of the LIGO-Virgo observational campaign, and we derive constraints on the kilonova properties assuming that the events' locations were imaged by our telescopes.