P. Pietrukowicz, D. Minniti, Ph. Jetzer, J. Alonso-Garcia, A. Udalski
In July/August 2000 a microlensing event occurred at a distance of 2.33
arcmin from the center of the globular cluster M22 (NGC6656), observed against
the dense stellar field of the Milky Way bulge. We have used the adaptive
optics system NACO at the ESO VLT to resolve the two objects that participated
in the event: the lens and the source. The position of the objects measured in
July 2011 is in agreement with the observed relative proper motion of M22 with
respect to the background bulge stars. Based on the brightness of the microlens
components we find that the source is a solar-type star located at a distance
of 6.9 +/-1.5 kpc in the bulge, while the lens is a 0.18 +/-0.01 Msun dwarf
member of the globular cluster located at the known distance of 3.2 +/-0.2 kpc
from the Sun.
View original:
http://arxiv.org/abs/1112.0562
No comments:
Post a Comment