Uncovering the Invisible: A Study of Gaia18ajz, a Candidate Black Hole Revealed by Microlensing

Abstract

Identifying black holes is essential for comprehending the development of stars and uncovering novel principles of physics. Gravitational microlensing provides an exceptional opportunity to examine an undetectable population of black holes in the Milky Way. In particular, long-lasting events are likely to be associated with massive lenses, including black holes. We present an analysis of the Gaia18ajz microlensing event, reported by the Gaia Science Alerts system, which has exhibited a long timescale and features indicative of the annual microlensing parallax effect. Our objective is to estimate the parameters of the lens based on the best-fitting model. We utilized photometric data obtained from the Gaia satellite and terrestrial observatories to investigate a variety of microlensing models and calculate the most probable mass and distance to the lens, taking into consideration a Galactic model as a prior. Subsequently, weapplied a mass-brightness relation to evaluate the likelihood that the lens is a main sequence star. We also describe the DarkLensCode (DLC), an open-source routine which computes the distribution of probable lens mass, distance and luminosity employing the Galaxy priors on stellar density and velocity for microlensing events with detected microlensing parallax. We modelled Gaia18ajz event and found its two possible models with most likely Einstein timescale of $316_{-30}^{+36}$ days and $299_{-22}^{+25}$ days. Applying Galaxy priors for stellar density and motion, we calculated the most probable lens mass of $4.9_{-2.3}^{+5.4}{M}_{\odot }$ located at $1.14_{-0.57}^{+0.75}\text{kpc}$ or $11.1_{-4.7}^{+10.3}{M}_{\odot }$ located at $1.31_{-0.60}^{+0.80}\text{kpc}$. Our analysis of the blended light suggests that the lens is likely a dark remnant of stellar evolution, rather than a main sequence star.

References in corpus (68)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Observation of Gravitational Waves from a Binary Black Hole Merger
• emcee: The MCMC Hammer
• Gaia Data Release 2. Summary of the contents and survey properties
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• On the variation of the Initial Mass Function
• The Gaia mission
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• Gaia Data Release 3: Summary of the content and survey properties
• MultiNest: an efficient and robust Bayesian inference tool for cosmology and particle physics
• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• GW170104: Observation of a 50-Solar-Mass Binary Black Hole Coalescence at Redshift 0.2
• Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-Main Sequence Stars
• dynesty: A Dynamic Nested Sampling Package for Estimating Bayesian Posteriors and Evidences
• Gaia Data Release 2: The astrometric solution
• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• Local Kinematics and the Local Standard of Rest
• Estimating distances from parallaxes IV: Distances to 1.33 billion stars in Gaia Data Release 2
• X-ray spectral modelling of the AGN obscuring region in the CDFS: Bayesian model selection and catalogue
• X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope
• Trigonometric Parallaxes of Massive Star Forming Regions: VI. Galactic Structure, Fundamental Parameters and Non-Circular Motions
• Determining stellar atmospheric parameters and chemical abundances of FGK stars with iSpec
• Gaia broad band photometry
• The Optical to Mid-Infrared Extinction Law Based on the APOGEE, Gaia DR2, Pan-STARRS1, SDSS, APASS, 2MASS and WISE Surveys
• BlackCAT: A catalogue of stellar-mass black holes in X-ray transients
• Modern stellar spectroscopy caveats
• Dynamic nested sampling: an improved algorithm for parameter estimation and evidence calculation
• A Natural Formalism for Microlensing
• Resolution of the MACHO-LMC-5 Puzzle: The Jerk-Parallax Microlens Degeneracy
• The Landscape of the Neutrino Mechanism of Core-Collapse Supernovae: Neutron Star and Black Hole Mass Functions, Explosion Energies and Nickel Yields
• Color-Magnitude Diagram Distribution of the Bulge Red Clump Stars - Evidence for the Galactic Bar
• Stellar Contribution to the Galactic Bulge Microlensing Optical Depth
• A Sun-like star orbiting a black hole
• Binary microlensing event OGLE-2009-BLG-020 gives a verifiable mass, distance and orbit predictions
• Atomic data for the Gaia-ESO Survey
• MOA-2009-BLG-387Lb: A massive planet orbiting an M dwarf
• Gaia Data Release 3: External calibration of BP/RP low-resolution spectroscopic data
• Black Hole, Neutron Star and White Dwarf Candidates from Microlensing with OGLE-III
• A red giant orbiting a black hole
• Rotation curve of the Milky Way from Classical Cepheids
• An isolated mass gap black hole or neutron star detected with astrometric microlensing
• Gaia Photometric Science Alerts
• Discovery of a dormant 33 solar-mass black hole in pre-release Gaia astrometry
• Relativistic deflection of background starlight measures the mass of a nearby white dwarf star
• Constraining the masses of microlensing black holes and the mass gap with Gaia DR2
• Optical Gravitational Lensing Experiment. OGLE-1999-BUL-32: the Longest Ever Microlensing Event -- Evidence for a Stellar Mass Black Hole?
• A non-interacting Galactic black hole candidate in a binary system with a main-sequence star
• The ultracompact nature of the black hole candidate X-ray binary 47 Tuc X9
• Astrometric Microlensing with the GAIA satellite
• Populations of stellar mass Black holes from binary systems
• The Formation of a 70 Msun Black Hole at High Metallicity
• Triage of the Gaia DR3 astrometric orbits. I. A sample of binaries with probable compact companions
• Search for a Black Hole Binary in Gaia DR3 Astrometric Binary Stars with Spectroscopic Data
• Modeling microlensing events with MulensModel
• Systematic errors as a source of mass discrepancy in black hole microlensing event OGLE-2011-BLG-0462
• On the accuracy of mass measurement for microlensing black holes as seen by Gaia and OGLE
• Gaia Data Release 3: Microlensing Events from All Over the Sky
• First semi-empirical test of the white dwarf mass-radius relationship using a single white dwarf via astrometric microlensing
• Gaia Data Release 3: Ellipsoidal Variables with Possible Black-Hole or Neutron Star secondaries
• Kojima-1Lb Is a Mildly Cold Neptune around the Brightest Microlensing Host Star
• Microlensing optical depth and event rate in the OGLE-IV Galactic plane fields
• Lens parameters for Gaia18cbf -- a long gravitational microlensing event in the Galactic plane
• Is there a nearby microlensing stellar remnant hiding in Gaia DR3 astrometry?
• Dark lens candidates from Gaia Data Release 3
• A spectroscopic follow-up for Gaia19bld
• Around Gaia Alerts in 20 questions
• MOCCA-Survey Database: Extra Galactic Globular Clusters. III. The population of black holes in Milky Way and Andromeda-like galaxies
• Interferometric visibility of single-lens models: the thin-arcs approximation

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