Header

UZH-Logo

Maintenance Infos

The first confirmed microlens in a globular cluster


Pietrukowicz, P; Minniti, D; Jetzer, P; Alonso-García, J; Udalski, A (2012). The first confirmed microlens in a globular cluster. Astrophysical Journal Letters, 744(2):L18.

Abstract

In 2000 July/August a microlensing event occurred at a distance of 2.33 arcmin from the center of the globular cluster M22 (NGC 6656), observed against the dense stellar field of the Milky Way bulge. We have used the adaptive optics system NACO at the ESO Very Large Telescope to resolve the two objects that participated in the event: the lens and the source. The position of the objects measured in 2011 July 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 6.0 ± 1.5 kpc in the bulge, while the lens is a 0.18 ± 0.01 M sun dwarf member of the globular cluster located at the known distance of 3.2 ± 0.2 kpc from the Sun.
Based on observations collected with the ESO VLT and VISTA telescopes at Paranal Observatory (ESO Programmes 087.C-0640(A) and 179.B-2002(B), respectively), and the 1.3 m Warsaw telescope at the Las Campanas Observatory of the Carnegie Institution for Science.

Abstract

In 2000 July/August a microlensing event occurred at a distance of 2.33 arcmin from the center of the globular cluster M22 (NGC 6656), observed against the dense stellar field of the Milky Way bulge. We have used the adaptive optics system NACO at the ESO Very Large Telescope to resolve the two objects that participated in the event: the lens and the source. The position of the objects measured in 2011 July 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 6.0 ± 1.5 kpc in the bulge, while the lens is a 0.18 ± 0.01 M sun dwarf member of the globular cluster located at the known distance of 3.2 ± 0.2 kpc from the Sun.
Based on observations collected with the ESO VLT and VISTA telescopes at Paranal Observatory (ESO Programmes 087.C-0640(A) and 179.B-2002(B), respectively), and the 1.3 m Warsaw telescope at the Las Campanas Observatory of the Carnegie Institution for Science.

Statistics

Citations

6 citations in Web of Science®
8 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

56 downloads since deposited on 22 Jan 2013
7 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute for Computational Science
Dewey Decimal Classification:530 Physics
Language:English
Date:January 2012
Deposited On:22 Jan 2013 07:38
Last Modified:15 Dec 2017 21:59
Publisher:IOP Publishing
ISSN:2041-8205
Publisher DOI:https://doi.org/10.1088/2041-8205/744/2/L18

Download

Download PDF  'The first confirmed microlens in a globular cluster'.
Preview
Filetype: PDF
Size: 233kB
View at publisher