How Rare are TESS Free-Floating Planets?
arxiv(2024)
摘要
Recently, Kunimoto et al. claimed that a short-lived signal in the Transiting
Exoplanet Survey Satellite (TESS) Sector 61 database was caused by a
microlensing event with a terrestrial-mass free-floating planet (FFP) lens. In
this study, we investigate TESS's ability to detect microlensing FFPs by
considering the detailed source information (e.g., distance and radius), the
TESS photometric accuracy, and finite-source effects. Using the FFP mass
function from microlensing surveys toward the Galactic bulge, we find that only
0.0018 microlensing events are expected to be detected in TESS Sector 61 for
the entire planetary mass range. The reported signal is unlikely to be a real
microlensing event, which is consistent with the evidence from the long-term
OGLE data that the signal was likely due to a stellar flare. By extrapolating
our result to fainter stars until T = 16 mag and adopting a possible
optimized search algorithm, we find that only ∼ 1 FFP events can be
detected in the entire TESS mission within the first 7 years. Significant
improvments of our understanding of FFPs still requires future satellite
missions, such as Roman and Earth 2.0, which can detect thousands of FFPs.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要