2001/10/31 by J. An, Jin H. An, Andrew Gould
Physics and Astronomy · #Astrophysics and Star Formation Studies #History and Developments in Astronomy #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/338657
published as Astrophys.J. 563 (2001) L111-L114 · revised version (abstract re-written, section 2 expanded), to appear in the Astrophysical Journal Letters
arxiv created 2001/11/13 · openalex publication_date 2001/12/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We show that one can measure the effects of microlens parallax for binary microlensing events with three well-measured peaks, two caustic crossings plus a cusp approach, and hence derive the projected Einstein radius E . Since the angular Einstein radius θ E is measurable from finite-source effects for almost any well-observed caustic crossing, triple-peak events can yield the determination of the lens mass M = ( c 2 /4 G ) E θ E . We note that, to a certain extent, rotation of the binary can mimic the effects of parallax, but it should often be possible to disentangle parallax from rotation by making use of the late-time light curve.