THE ORBIT OF THE STAR S2 AROUND SGR A* FROM VERY LARGE TELESCOPE AND KECK DATA

By S. Gillessen, F. Eisenhauer, T. Fritz, H. Bartko, K. Dodds-Eden, O. Pfuhl, T. Ott, R. Genzel. 2009

250 citations recorded by the source corpus.

Two recent papers (Ghez et al. 2008; Gillessen et al. 2009) have estimated the mass of and the distance to the massive black hole (MBH) in the center of the Milky Way using stellar orbits. The two astrometric data sets are independent and yielded consistent results, even though the measured positions do not match when simply overplotting the two sets. In this Letter, we show that the two sets can be brought to excellent agreement with each other when we allow for a small offset in the definition of the reference frame of the two data sets. The required offsets in the coordinates and velocities of the origin of the reference frames are consistent with the uncertainties given in Ghez et al. The so-combined data set allows for a moderate improvement of the statistical errors of the mass of and the distance to Sgr A*, but the overall accuracies of these numbers are dominated by systematic errors and the long-term calibration of the reference frame. We obtain R0 = 8.28 ± 0.15|stat ± 0.29|sys kpc and MMBH = 4.30 ± 0.20|stat ± 0.30|sys × 106 M☉ as best estimates from a multi-star fit.

Subfields: Astronomy and Astrophysics, Atomic and Molecular Physics, and Optics

View Paper: https://www.semanticscholar.org/paper/f110475c72de7cb40ebf5bbeb4dcea64377bac4c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Atomic and Molecular Physics, and Optics

Citations in the corpus

Constraining the Galaxy's dark halo with RAVE stars (2014, background): “In order to make model predictions for these measurements, we assume a distance of the Sun to the GC, R0, to be 8.3 kpc (e.g. Gillessen et al. 2009; McMillan 2011; Schönrich 2012), the position of the Sun above the Galactic plane, z0, to be 14 pc (Binney, Gerhard & Spergel 1997) and the solar…”
Detection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole (2020, methodology): “They determined increasingly precise motions for more than 104 stars, and orbits for ≈ 50 (Schödel et al. 2002; Ghez et al. 2003, 2008; Eisenhauer et al. 2005; Gillessen et al. 2009b; Schödel et al. 2009; Meyer et al. 2012; Boehle et al. 2016; Fritz et al. 2016; Gillessen et al. 2017).”
Hot Accretion Flows Around Black Holes (2014, background): “Observations of O and B stars orbiting the Galactic Center (Schödel et al. 2002; Ghez et al. 2003, 2008; Gillessen et al. 2009a, 2009b; Meyer et al. 2012) provide very strong evidence for the presence of a dark compact object of mass (4.1± 0.4)× 106 M⊙.”
An Update on Monitoring Stellar Orbits in the Galactic Center (2016, methodology): “A few years later, orbits for a handful of stars had been determined (Ghez et al. 2005; Eisenhauer et al. 2005), and again a few years later, the number of known orbits exceeded 20 (Gillessen et al. 2009b).”
Dense gas in the Galactic central molecular zone is warm and heated by turbulence (2015, background): “…derived temperatures are usually assumed and often observed to agree in Galactic disk clouds (Pillai et al. 2006; Dunham et al. 2010; Juvela et al. 2012; Battersby et al. 1 Assuming the IAU-recommended d = 8.5 kpc (Ghez et al. 2008; Gillessen et al. 2009; Reid et al. 2009; Gillessen et al. 2013).”
STELLAR POPULATIONS IN THE CENTRAL 0.5 pc OF THE GALAXY. II. THE INITIAL MASS FUNCTION (2013, background): “…of the Galaxy can be divided into several different kinematic sub-groups (Paumard et al. 2006; Ghez et al. 2008; Lu et al. 2009; Bartko et al. 2009; Gillessen et al. 2009b), it is not yet clear whether these sub-groups have different origins, or whether all the young stars formed from the same…”
Gamma-ray spectroscopy of Positron Annihilation in the Milky Way (2015, background): “The supermassive black hole in the centre of the Milky Way with (4.31 ± 0.38) × 106 M (Gillessen et al. 2009) and its associated accretion disk extending up to 100 AU (Genzel et al. 2010, and references therein) have been discussed as positron sources (Totani et al. 2006; Cheng et al. 2006).”
The old Nuclear Star Cluster in the Milky Way (2014, methodology): “Gillessen et al. (2009) find that the largest uncertainty in the value obtained for M• is due to the uncertainty in R0, and that M• scales as M• ∝ R2.”
Eccentric Black Hole Gravitational-wave Capture Sources in Galactic Nuclei: Distribution of Binary Parameters (2017, background): “13BH SMBH SgrA Here, *MSgrA =4.3×10 6 M is the mass of the SMBH, Sgr A*, in the Milky Way-size nucleus (Gillessen et al. 2009).9 The number density distribution of BHs in this single-mass model is of the form = a-⎛ ⎝⎜ ⎞ ⎠⎟ ( )n C n r r , 14BH,s BH,s inf,MS max BH,s where CBH,s can be determined…”
A UNIVERSAL, LOCAL STAR FORMATION LAW IN GALACTIC CLOUDS, NEARBY GALAXIES, HIGH-REDSHIFT DISKS, AND STARBURSTS (2011, unknown): “One is torb evaluated at the galactocentric radius of the molecular clouds, which is roughly equal to the r ≈ 8 kpc radius of the Sun (Ghez et al. 2008; Gillessen et al. 2009) since most of the clouds are closer than 1 kpc.”
Detection of the gravitational redshift in the orbit of the star S2 near the Galactic centre massive black hole (2018, methodology): “We do not use the ’combined’ data set in the sense of Gillessen et al. (2009a), that is, we do not include the astrometric data set presented in Boehle et al. (2016), but use NTT and VLT astrometry only.”
The Galaxy in Context: Structural, Kinematic, and Integrated Properties (2016, methodology): “See also Gillessen et al. (2009a), who combined the existing two major data sets in a joint analysis.”
EVIDENCE FOR LOW BLACK HOLE SPIN AND PHYSICALLY MOTIVATED ACCRETION MODELS FROM MILLIMETER-VLBI OBSERVATIONS OF SAGITTARIUS A* (2010, background): “These have yieldedM = 4.3± 0.5× 106M⊙ and D = 8.3± 0.4kpc, respectively, where both include thesystematicuncertainties (Ghez et al. 2008; Gillessen et al. 2009b,a).”
AN IMPROVED DISTANCE AND MASS ESTIMATE FOR SGR A* FROM A MULTISTAR ORBIT ANALYSIS (2016, methodology): “Orbital fits of S0-2 performed in this work used these new radial velocities as well as previously reported radial velocities from both Keck and VLT (originally published in Ghez et al. 2008 and Gillessen et al. 2009b; also see Gillessen et al. 2009a in which both data sets are presented together).”