An Improved Distance and Mass Estimate for Sgr A* from a Multistar Orbit Analysis

Abstract

We present new, more precise measurements of the mass and distance of our Galaxy's central supermassive black hole, Sgr A*. These results stem from a new analysis that more than doubles the time baseline for astrometry of faint stars orbiting Sgr A*, combining two decades of speckle imaging and adaptive optics data. Specifically, we improve our analysis of the speckle images by using information about a star's orbit from the deep adaptive optics data (2005 - 2013) to inform the search for the star in the speckle years (1995 - 2005). When this new analysis technique is combined with the first complete re-reduction of Keck Galactic Center speckle images using speckle holography, we are able to track the short-period star S0-38 (K-band magnitude = 17, orbital period = 19 years) through the speckle years. We use the kinematic measurements from speckle holography and adaptive optics to estimate the orbits of S0-38 and S0-2 and thereby improve our constraints of the mass ($M_{bh}$) and distance ($R_o$) of Sgr A*: $M_{bh}=4.02\pm 0.16\pm 0.04\times 10^6{M}_{\odot }$ and $7.86\pm 0.14\pm 0.04$ kpc. The uncertainties in $M_{bh}$ and $R_o$ as determined by the combined orbital fit of S0-2 and S0-38 are improved by a factor of 2 and 2.5, respectively, compared to an orbital fit of S0-2 alone and a factor of $\sim$2.5 compared to previous results from stellar orbits. This analysis also limits the extended dark mass within 0.01 pc to less than $0.13\times 10^6{M}_{\odot }$ at 99.7% confidence, a factor of 3 lower compared to prior work.

56 pages, 14 figures, accepted to ApJ

References in corpus (3)

• Stellar remnants in galactic nuclei: mass segregation
• The old nuclear star cluster in the Milky Way: dynamics, mass, statistical parallax, and black hole mass
• Photometric Stellar Variability in the Galactic Center

Cited by in corpus (94)

• The mass distribution and gravitational potential of the Milky Way
• First Sagittarius A* Event Horizon Telescope Results. VI: Testing the Black Hole Metric
• Detection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole
• An Update on Monitoring Stellar Orbits in the Galactic Center
• The mass distribution in the Galactic Centre from interferometric astrometry of multiple stellar orbits
• Testing General Relativity with stellar orbits around the supermassive black hole in our Galactic center
• Improved GRAVITY astrometric accuracy from modeling of optical aberrations
• The shape of the inner Milky Way halo from observations of the Pal 5 and GD-1 stellar streams
• Twelve years of spectroscopic monitoring in the Galactic Center: the closest look at S-stars near the black hole
• Millimeter light curves of Sagittarius A* observed during the 2017 Event Horizon Telescope campaign
• The Survey of Water and Ammonia in the Galactic Center (SWAG): Molecular Cloud Evolution in the Central Molecular Zone
• Investigating the Relativistic Motion of the Stars Near the Supermassive Black Hole in the Galactic Center
• A population of dust-enshrouded objects orbiting the Galactic black hole
• General relativistic effects on the orbit of the S2 star with GRAVITY
• A new Fokker-Planck approach for relaxation-driven evolution of galactic nuclei
• New constraints on the structure of the nuclear stellar cluster of the Milky Way from star counts and MIR imaging
• Importance of transient resonances in extreme-mass-ratio inspirals
• A Cool Accretion Disk around the Galactic Centre Black Hole
• Kinematics of OB-associations in Gaia epoch
• S62 on a 9.9 yr Orbit around SgrA*
• Search for a Variation of the Fine Structure around the Supermassive Black Hole in Our Galactic Center
• Carbon isotopic fractionation in molecular clouds
• Recent advances in the determination of some Galactic constants in the Milky Way
• Kinematic Structure of the Galactic Center S-cluster
• The dark mass signature in the orbit of S2
• Test of Einstein equivalence principle near the Galactic center supermassive black hole
• Median Statistics Estimate of the Distance to the Galactic Center
• Comparing timelike geodesics around a Kerr black hole and a boson star
• Spectroscopic Detection of a Cusp of Late-type Stars around the Central Black Hole in the Milky Way
• Spectral and Imaging properties of Sgr A* from High-Resolution 3D GRMHD Simulations with Radiative Cooling
• Choosing a Maximum Drift Rate in a SETI Search: Astrophysical Considerations
• Observation of S4716 -- a Star with a 4 yr Orbit around Sgr A*
• The Post-Periapse Evolution of Galactic Center Source G1: The second case of a resolved tidal interaction with a supermassive black hole
• An X-ray survey of the central molecular zone: variability of the Fe Ka emission line
• Bright X-ray flares from Sgr A*
• The Second Galactic Center Black Hole?; A Possible Detection of Ionized Gas Orbiting around an IMBH embedded in the Galactic Center IRS13E complex
• The Galactic Center: An Improved Astrometric Reference Frame for Stellar Orbits around the Supermassive Black Hole
• Near-Infrared Variability Study of the Central 2.3 arcmin x 2.3 arcmin of the Galactic Centre II. Identification of RR Lyrae Stars in the Milky Way Nuclear Star Cluster
• The Galactic Center: Improved Relative Astrometry for Velocities, Accelerations, and Orbits near the Supermassive Black Hole
• Origins of Scatter in the Relationship Between HCN 1-0 and Dense Gas Mass in the Galactic Center
• Visibility of Black Hole Shadows in Low-luminosity AGN
• Active Galactic Nuclei: Boon or Bane for Biota?
• Testing modified gravity via Yukawa potential in two body problem: Analytical solution and observational constraints
• The centres of M83 and the Milky Way: opposite extremes of a common star formation cycle
• Probing the formation history of the nuclear star cluster at the Galactic Centre with millisecond pulsars
• Einstein Quartic Gravity: Shadows, Signals, and Stability
• Proper motion survey and kinematic analysis of the Rho Ophiuchi embedded cluster
• A "coronal-mass-ejection'' model for flares in Sagittarius A*
• Star formation at the Galactic Centre: coevolution of multiple young stellar discs
• The influence of the secular perturbation of an intermediate-mass companion: I. Eccentricity excitation of disk stars at the Galactic center
• M0.20-0.033: An Expanding Molecular Shell in the Galactic Center Radio Arc
• Simultaneous Monitoring of X-ray and Radio Variability in Sagittarius A*
• Cosmological acceleration
• Evidence of a Decreased Binary Fraction for Massive Stars Within 20 Milliparsecs of the Supermassive Black Hole at the Galactic Center
• Bremsstrahlung in GRMHD models of accreting black holes
• Multi-wavelength Variability of Sagittarius A* in July 2019
• First results from a large-scale proper motion study of the Galactic Centre
• ALMA and VLA observations of emission from the environment of Sgr A*
• A Significant Feature in the General Relativistic Time Evolution of the Redshift of Photons Coming from a Star Orbiting Sgr A*
• Close stellar encounters at the Galactic Centre I: The effect on the observed stellar populations
• Comparison of the Asteroseismic Mass Scale of Red Clump Giants with Photometric Mass Estimates
• Near-Infrared Variability Study of the Central 2.3 arcmin x 2.3 arcmin of the Galactic Centre I. Catalog of Variable Sources
• Fermi LAT observations of Sagittarius A*: Imaging Analysis
• The Swansong of the Galactic Center Source X7: An Extreme Example of Tidal Evolution near the Supermassive Black Hole
• A Rapidly Varying Red Supergiant X-Ray Binary in the Galactic Center
• Potential Black Hole Seeding of the Spiral Galaxy NGC 4424 via an Infalling Star Cluster
• Splitting the lentils: Clues to galaxy/black hole coevolution from the discovery of offset relations for non-dusty versus dusty (wet-merger-built) lenticular galaxies in the $M_{\mathrm{bh}}$-$M_{\ast ,\mathrm{spheroid}}$ diagram
• Distance scale for high-luminosity stars in OB associations and in field with Gaia DR2. Spurious systematic motions
• Galactic resonance rings. Modelling of motions in the wide solar neighborhood
• On Detecting Nearby Nano-Hertz Gravitational Wave Sources via Pulsar Timing Arrays
• Upper Limit on Brackett-gamma Emission from the Immediate Accretion Flow onto the Galactic Black Hole
• Time Domain Filtering of Resolved Images of Sgr A*
• Discovery of a Planar Black Hole Mass Scaling Relation for Spiral Galaxies
• Influence of the Galactic bar on the kinematics of the disc stars with Gaia EDR3 data
• Where is the Western Part of the Galactic Center Lobe Located really?
• Three-dimensional analysis of the Minispiral at the Galactic Center: orbital parameters, periods and the mass of the black hole
• Eclipsing Stellar Binaries in the Galactic Center
• Feeding of active galactic nuclei by dynamical perturbations
• Searching for clues of past binary supermassive black hole mergers in nuclear star clusters
• Gravitational Burst Radiation from Pulsars in the Galactic centre and stellar clusters
• Radio timing in a millisecond pulsar-extreme/intermediate mass ratio binary system
• Improving Black Hole Accretion Treatment in Hydrodynamical Simulations
• Possible evidence from the flaring activity of Sgr A* for a star at a distance of ~3.3 Schwarzscild radii from the blackhole
• Probing Accretion Turbulence in the Galactic Center with EHT Polarimetry
• G-0.02-0.07, the Compact HII Region Complex nearest to the Galactic Center with ALMA
• Constraints on the abundance of $0.01c$ stellar engines in the Milky Way
• On the effects of UV photons/X-rays on the chemistry of the Sgr B2 cloud
• Distribution of Phantom Dark Matter in Dwarf Spheroidals
• Stellar rotation as a new observable to test general relativity in the Galactic Center
• Accelerations of stars in central 2-7 arcsec from Sgr A*
• Constraining cosmic-ray acceleration in the magnetospheric gaps of Sgr A*
• Herschel water maps towards the vicinity of the black hole Sgr A*
• Disks of Stars in the Galactic center triggered by Tidal Disruption Events
• A Fundamental Plane in X-ray Binary Activity of External Galaxies