Large Interferometer For Exoplanets (LIFE) : X. Detectability of currently known exoplanets and synergies with future IR/O/UV reflected-starlight imaging missions

Context. The next generation of space-based observatories will characterize the atmospheres of low-mass, temperate exoplanets with the direct-imaging technique. This will be a major step forward in our understanding of exoplanet diversity and the prevalence of potentially habitable conditions beyond the Earth.Aims. We compute a list of currently known exoplanets detectable with the mid-infrared Large Interferometer For Exoplanets (LIFE) in thermal emission. We also compute the list of known exoplanets accessible to a notional design of the future Habitable Worlds Observatory (HWO), observing in reflected starlight.Methods. With a pre-existing statistical methodology, we processed the NASA Exoplanet Archive and computed orbital realizations for each known exoplanet. We derived their mass, radius, equilibrium temperature, and planet-star angular separation. We used the LIFEsim simulator to compute the integration time (t(int)) required to detect each planet with LIFE. A planet is considered detectable if a broadband signal-to-noise ratio S/N = 7 is achieved over the spectral range 4-18.5 mu m in t(int) < 100 h. We tested whether the planet is accessible to HWO in reflected starlight based on its notional inner and outer working angles, and minimum planet-to-star contrast.Results. LIFE's reference configuration (four 2-m telescopes with 5% throughput and a nulling baseline between 10-100 m) can detect 212 known exoplanets within 20 pc. Of these, 49 are also accessible to HWO in reflected starlight, offering a unique opportunity for synergies in atmospheric characterization. LIFE can also detect 32 known transiting exoplanets. Furthermore, we find 38 LIFE-detectable planets orbiting in the habitable zone, of which 13 have M-p < 5M(circle plus) and eight have 5M(circle plus) < M-p < 10M(circle plus).Conclusions. LIFE already has enough targets to perform ground-breaking analyses of low-mass, habitable-zone exoplanets, a fraction of which will also be accessible to other instruments.

Automated summary

In this study, the authors use a statistical methodology to process the NASA Exoplanet Archive and compute orbital realizations for known exoplanets. They find that the mid-infrared Large Interferometer For Exoplanets (LIFE) and the future Habitable Worlds Observatory (HWO) have the capability to detect and characterize a large number of exoplanets. Specifically, LIFE can detect 212 known exoplanets, 49 of which are also accessible to HWO in reflected starlight. This study highlights the potential for groundbreaking analyses of low-mass, habitable-zone exoplanets.