J/A+A/313/841 MACHO LMC No.1 microlensing event (Dominik+, 1996)
Evidence for a binary lens in the MACHO LMC No.1 microlensing event
Dominik M., Hirshfeld A.C.
<Astron. Astrophys. 313, 841 (1996)>
=1996A&A...313..841D 1996A&A...313..841D (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational lensing
Keywords: dark matter - gravitational lenses -
stars: low-mass, brown dwarfs - Galaxy: halo
Description:
During the last three years, several galactic microlensing events
towards the Large Magellanic Cloud and the Galactic Bulge have been
detected by four observing groups (MACHO, EROS, OGLE, DUO). Most of
these are commonly explained as due to microlensing of a point source
by a point mass lens. In this paper, we discuss statistical methods to
determine the goodness-of-fit for a specific model of source and lens
beyond the assumption that the errors are normal. In particular, we
argue that the MACHO LMC#1 event has been caused by a binary lens and
thereby confirm our hypothesis (Dominik & Hirshfeld 1994). We also
show that the binary lens fit is not unique by presenting alternative
plausible binary lens fits. We emphasize that knowledge of the
fraction of binaries among the observed microlensing events is crucial
for estimating the mass distribution of the observed dark objects. We
finally show that for each data set of parameters for a binary source,
two physical configurations with different distances between the
components exist which produce exactly the same light curve.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
appen.tex 85 280 LaTeX version of appendix A, B and C
fig5a.ps 76 13347 PostScript file with Figure 5a
fig5b.ps 76 14044 PostScript file with Figure 5b
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Courtesy: Martin Dominik
(End) Patricia Bauer [CDS] 02-Apr-1996