Rapid method for preliminary identification of subthreshold strongly lensed counterparts to superthreshold gravitational-wave events

We are thankful to P. Ajith, D. Chatterjee, H. Fong, and A. Barsode along with the astrophysical relativity group at ICTS and the LVK lensing group for helpful discussions and suggestions. We are also thankful to D. Keitel, M. Wright, and J. Janquart for their careful reading of this manuscript. Juno C. L. Chan acknowledges support from the Villum Investigator program supported by VILLUM FONDEN (Grant No. 37766) and the DNRF Chair, by the Danish Research Foundation. J. R. Cudell benefits from the support of the Fonds de la Recherche Scientifique-FNRS, Belgium, under Grant No. 4.4501.19. The authors are grateful for computational resources provided by the LIGO Laboratory and supported by National Science Foundation Grants No. PHY-0757058 and No. PHY-0823459. This research has made use of data or software obtained from the Gravitational Wave Open Science Center, a service of LIGO Laboratory, the LIGO Scientific Collaboration, the Virgo Collaboration, and KAGRA. LIGO Laboratory and Advanced LIGO are funded by the United States National Science Foundation (NSF), as well as the Science and Technology Facilities Council (STFC) of the United Kingdom, the Max-Planck-Society (MPS), and the State of Niedersachsen/Germany for support of the construction of Advanced LIGO and construction and operation of the GEO600 detector. Additional support for Advanced LIGO was provided by the Australian Research Council. Virgo is funded, through the European Gravitational Observatory (EGO), by the French Centre National de Recherche Scientifique (CNRS), the Italian Istituto Nazionale di Fisica Nucleare (INFN), and the Dutch Nikhef, with contributions by institutions from Belgium, Germany, Greece, Hungary, Ireland, Japan, Monaco, Poland, Portugal, and Spain. K.A.G.R.A. is supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), the Japan Society for the Promotion of Science (JSPS) in Japan; the National Research Foundation (NRF) and Ministry of Science and ICT (MSIT) in Korea; the Academia Sinica (AS) and National Science and Technology Council (NSTC) in Taiwan. This material is based upon work supported by NSF’s LIGO Laboratory, which is a major facility fully funded by the National Science Foundation. A. K. Y. L. would like to gratefully acknowledge the support from the National Science Foundation through the Grants NSF PHY-1912594 and NSF PHY-2207758.