Composite figure showing the geometry of a microlensing event. The
insets show a picture of the Large Magellanic Cloud and the Great
Melbourne Telescope in Canberra, Australia where the MACHO Project
collected microlensing survey data for eight years. A MACHO in the
halo of the Milky Way is shown bending light from a star in the Large
Magellanic Cloud on its path to the telescope in Australia.
Three color Hubble Space Telescope-image of LMC-5. We show a
three-color composite image of the WFPC2 V, R, and I band images of
LMC-5. The microlensing source star is the blue star near the center of the
figure which is partially blended with a much redder object (indicated
by arrow) displaced by 0.134''. The direction of motion of the lens on the
sky derived from the Hubble data (Theta_{HST,sky} = -92 degrees) and the
microlensing parallax fit (Theta_{PAR,sky} = -100 degrees) are both shown.
We show a composite European Southern Observatory Very Large
Telescope FORS2 spectrum of the LMC-5 source-lens system from
4 x 1500 second exposures on February 2, 2001. The potassium,
sodium and titanium oxide features from the lens are marked. The calcium lines
are a blend from both the lens and the LMC source star (spectral type F). The
presence of KI, NaI, the absence of CsI + RbI and the TiO band at 7100
Angstroms with corresponding absence of the VO band at 7450
Angstroms lead us to conclude that the lens is of spectral type M4-5V.
The spectrum has been put on a relative flux scale and smoothed to a
resolution of about 3 Angstroms
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