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Microlensing Constraints on the Mass of Single Stars from HST Astrometric Measurements

Journal Article · · The Astrophysical Journal (Online)
 [1];  [1];  [1];  [1];  [1];  [2];  [3];  [4];  [5];  [6];  [7];  [8];  [9];  [10];  [11];  [12]
  1. Space Telescope Science Inst., Baltimore, MD (United States)
  2. Warsaw Univ. Observatory, Warsaw (Poland)
  3. Pontificia Universidad Catolica de Chile, Santiago (Chile). Inst. de Astrofisica; Millennium Inst. of Astrophysics, Santiago (Chile)
  4. Space Telescope Science Inst., Baltimore, MD (United States); Pennsylvania State Univ., University Park, PA (United States). Dept of Astronomy & Astrophysics
  5. Univ. of Canterbury, Christchurch (New Zealand). Dept. of Physics and Astronomy
  6. Massey Univ., Auckland (New Zealand). Inst. of Natural and Mathematical Sciences
  7. Space Telescope Science Inst., Baltimore, MD (United States)
  8. Univ. of St Andrews, St Andrews (United Kingdom). SUPA, School of Physics & Astronomy
  9. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  10. Univ. of Nevada, Las Vegas, NV (United States). Dept. of Physics and Astronomy
  11. Chinese Academy of Sciences, Beijing (China). National Astronomical Observatories
  12. European Southern Observatory, Garching (Germany)
+ Show Author Affiliations

Here, we report on the first results from a large-scale observing campaign aiming to use astrometric microlensing to detect and place limits on the mass of single objects, including stellar remnants. We used the Hubble Space Telescope to monitor stars near the Galactic Center for three years, and we measured the brightness and positions of ~2 million stars at each observing epoch. In addition to this, we monitored the same pointings using the VIMOS imager on the Very Large Telescope. The stars we monitored include several bright microlensing events observed from the ground by the OGLE collaboration. In this paper, we present the analysis of our photometric and astrometric measurements for six of these events, and derive mass constraints for the lens in each of them. Although these constraints are limited by the photometric precision of ground-based data, and our ability to determine the lens distance, we were able to constrain the size of the Einstein ring radius thanks to our precise astrometric measurements—the first routine measurements of this type from a large-scale observing program. In conclusion, this demonstrates the power of astrometric microlensing as a tool to constrain the masses of stars, stellar remnants, and, in the future, extrasolar planets, using precise ground- and space-based observations.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20)
Grant/Contract Number:
AC52-06NA25396
OSTI ID:
1414115
Report Number(s):
LA-UR--17-23731
Journal Information:
The Astrophysical Journal (Online), Journal Name: The Astrophysical Journal (Online) Journal Issue: 2 Vol. 843; ISSN 1538-4357
Publisher:
Institute of Physics (IOP)Copyright Statement
Country of Publication:
United States
Language:
English

References (30)

Discovery of a cool planet of 5.5 Earth masses through gravitational microlensing journal January 2006
Transiting extrasolar planetary candidates in the Galactic bulge journal October 2006
Constraining the parameters of globular cluster NGC 1904 from its variable star population journal November 2012
A giant planet beyond the snow line in microlensing event OGLE-2011-BLG-0251 journal March 2013
Estimating the parameters of globular cluster M 30 (NGC 7099) from time-series photometry journal June 2013
A census of variability in globular cluster M 68 (NGC 4590) journal June 2015
Gravitational microlensing by the galactic halo journal May 1986
Astrometric Microlensing of Stars journal May 2000
Toward High‐Precision Astrometry with WFPC2. I. Deriving an Accurate Point‐Spread Function journal October 2000
First Microlens Mass Measurement: PLANET Photometry of EROS BLG‐2000‐5 journal June 2002
[ITAL]Hubble Space Telescope[/ITAL] WFPC2 Proper Motions in Two Bulge Fields: Kinematics and Stellar Population of the Galactic Bulge journal October 2002
The Rotation of the Globular Cluster 47 Tucanae in the Plane of the Sky journal August 2003
Resolution of the MACHO‐LMC‐5 Puzzle: The Jerk‐Parallax Microlens Degeneracy journal May 2004
Potential Direct Single‐Star Mass Measurement journal November 2004
OGLE‐2003‐BLG‐238: Microlensing Mass Estimate of an Isolated Star journal December 2004
Stellar Proper Motions in the Galactic Bulge from Deep Hubble Space Telescope ACS WFC Photometry journal September 2008
SPITZER AS A MICROLENS PARALLAX SATELLITE: MASS MEASUREMENT FOR THE OGLE-2014-BLG-0124L PLANET AND ITS HOST STAR journal February 2015
Criteria for Sample Selection to Maximize Planet Sensitivity and Yield from Space-Based Microlens Parallax Surveys journal September 2015
WFIRST PLANET MASSES FROM MICROLENS PARALLAX journal June 2013
Difference image analysis: extension to a spatially varying photometric scale factor and other considerations journal November 2012
The OGLE-III planet detection efficiency from six years of microlensing observations (2003–2008) journal February 2016
Searching for intermediate-mass black holes in globular clusters with gravitational microlensing journal May 2016
Stochastic distributions of lens and source properties for observed galactic microlensing events journal April 2006
Systematic trends in Sloan Digital Sky Survey photometric data: Systematic trends in SDSS photometric data journal July 2012
A new algorithm for difference image analysis journal May 2008
Commissioning and performances of the VLT-VIMOS conference March 2003
Discovery of a Jupiter/Saturn Analog with Gravitational Microlensing journal February 2008
Gravitational Microlensing in the Local Group journal September 1996
SPITZER PARALLAX OF OGLE-2015-BLG-0966: A COLD NEPTUNE IN THE GALACTIC DISK journal March 2016
A Search for Stellar-Mass Black Holes via Astrometric Microlensing journal October 2016

Cited By (10)

Predicted microlensing events from analysis of Gaia Data Release 2 journal October 2018
Full orbital solution for the binary system in the northern Galactic disc microlensing event Gaia16aye journal January 2020
A predicted astrometric microlensing event by a nearby white dwarf journal April 2018
Weak deflection gravitational lensing for photons coupled to Weyl tensor in a Schwarzschild black hole journal March 2018
A predicted astrometric microlensing event by a nearby white dwarf text January 2018
Chemically Dissected Rotation Curves of the Galactic Bulge from Main-sequence Proper Motions journal May 2018
Toward the Measurement of the Mass of Isolated Neutron Stars: Prediction of Future Astrometric Microlensing Events by Pulsars journal October 2018
A Search for Black Hole Microlensing Signatures in Globular Cluster NGC 6656 (M22) journal October 2018
Chemically-dissected rotation curves of the Galactic Bulge from Main Sequence proper motions text January 2018
Full orbital solution for the binary system in the northern Galactic disc microlensing event Gaia16aye text January 2019

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Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
astrometry
gravitational lensing micro
stars black holes
stars general