Open AccessDetection of stellar spots from the observations of caustic‐crossing binary‐lens gravitational microlensing events
Author(s) -
Han Cheongho,
Park SeongHong,
Kim HoIl,
Chang Kyongae
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03534.x
Subject(s) - gravitational microlensing , physics , caustic (mathematics) , lens (geology) , gravitational lens , astrophysics , binary number , light curve , astronomy , spots , binary star , event (particle physics) , optics , stars , galaxy , chemistry , arithmetic , mathematics , redshift , mathematical physics
Recently, Heyrovský & Sasselov investigated the sensitivity of single‐lens gravitational microlensing event light curves to spots and found that, during source transit, spots can cause deviations in amplification larger than 2 per cent, and thus be detectable. In this paper, we explore the feasibility of spot detection from the observations of binary‐lens microlensing events instead of single‐lens events. For this we investigate the sensitivity of binary‐lens event light curves to spots and compare it with that of single‐lens events. From this investigation, we find that during caustic crossings the fractional amplification deviations of light curves from those of spotless source events are equivalent to those of single‐lens events, implying that spots can also be detected with a similar photometric precision to that required for spot detection by observing single‐lens events. We discuss the relative advantages of observing binary‐lens events over the observations of single‐lens events in detecting stellar spots.