Kavli Affiliate: Subo Dong
| Summary:
Recent studies found a number of short-timescale microlensing events that are thought to be produced by free-floating or wide-orbit planets. The microlensing event KMT-2024-BLG-0792/OGLE-2024-BLG-0516 is currently the only free-floating planet candidate with a directly measured mass ($0.73^+0.25_-0.15$ Saturn masses), derived from joint ground-based and Gaia satellite observations. However, it remains unclear whether the lens is truly isolated or bound to a widely separated host star. Here, we report high-angular-resolution interferometric observations of the event obtained with the Very Large Telescope Interferometer/GRAVITY instrument two years after peak magnification. We detect no luminous host star up to a projected separation of 90 au, supporting the hypothesis that the lens is indeed a free-floating planet. We derive a 5 sigma upper limit on the mass of a putative host star of approximately 0.5-0.6 M_solar. This work demonstrates that interferometry provides a powerful method for directly searching for or constraining host stars in short-duration and planetary microlensing events.
| Search Query: arXiv Query: search_query=au:”Dong Subo”&id_list=&start=0&max_results=10
Read More