Orateur
Description
Very short period double white dwarfs (DWDs) in our Milky Way (MW) will be one of the most numerous classes of sources detectable by the upcoming Laser Interferometer Space Antenna (LISA), with its scientific return strongly enhanced by the availability of electromagnetic (EM) counterparts. This makes the present an ideal opportunity to chart the population of (potential) LISA sources across the MW. We developed a strategy to identify LISA source candidates in multiband photometric surveys, in order to select targets for further follow-up and characterisation. Starting from a theoretical population of Galactic WDs, combined with a consistent cooling model for the evolution, we constructed a synthetic EM catalogue of WD detections. We find that the resulting magnitude and colour distributions can help us distinguish LISA source candidates from the broader white dwarf population: the former populate a specific area in colour-colour diagram, with little contamination from single systems and wide binaries. This method is now guiding the design of a proposal for the Canada-France-Hawaii Telescope community survey (2027-2033). Expanding the EM catalogue of ultra-compact DWDs is only the first step: correctly matching LISA detections to their EM counterpart will not be straightforward, as LISA’s sky localisation remains less constrained. The accuracy of such identifications will depend on the precision and completeness of the EM characterisation of the system, which must drive the planning of follow-up observations.