1999/11/15 by Cheongho Han, S.-H. Park, Seong-Hong Park +2
Physics and Astronomy · #Adaptive optics and wavefront sensing #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2000.03293.x
published as CNU-A&SS-12/08 · total 6 pages, including 5 Figures and no Table, submitted to MNRAS
arxiv created 1999/11/15 · openalex publication_date 2000/05/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Detection of caustic crossings of binary-lens gravitational microlensing events is important because by detecting them one can obtain useful information about both the lens and the source star. In this paper, we compute the distribution of the intervals between two successive caustic crossings, f(tcc), for Galactic bulge binary-lens events to investigate the observational strategy for the optimal detection and resolution of caustic crossings. From this computation, we find that the distribution is highly skewed towards short tcc and peaks at tcc∼1.5 d. For the maximal detection of caustic crossings, therefore, prompt initiation of follow-up observations for intensive monitoring of events will be important. We estimate that, under the strategy of the current follow-up observations with a second caustic-crossing preparation time of ∼2 d, the fraction of events with resolvable caustic crossing is ∼80 per cent. We find that if the follow-up observations can be initiated within 1 d after the first caustic crossing by adopting more aggressive observational strategies, the detection rate can be improved to ∼90 per cent.