SINFONI in the Galactic Center: Young Stars and Infrared Flares in the Central Light‐Month

2005/02/06 by F. Eisenhauer, R. Genzel, Tal Alexander +27 · 672 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Galactic Center #Galaxy #Physics #Stars #Stellar, planetary, and galactic studies #Supermassive black hole #astro-ph

paper · pdf · doi:10.1086/430667

published in The Astrophysical Journal 628(1), 246-259 (IOP Publishing) · 50 pages, 10 figures, 2 tables, submitted to ApJ, February 6th, 2005, abstract abridged

arxiv created 2005/02/06 · openalex publication_date 2005/07/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We report on 75 mas resolution, near-IR imaging spectroscopy within the central 30 lt-days of the Galactic center, taken with the new adaptive optics-assisted integral-field spectrometer SINFONI on the ESO VLT. To a limiting magnitude of K ~ 16, 9 of 10 stars in the central 0 4, and 13 of 17 stars out to 0 7 from the central black hole have spectral properties of B0-B9 main-sequence stars. Based on the 2.1127 μm He I line width, all brighter early-type stars have normal rotation velocities, similar to solar neighborhood stars. We combine the new radial velocities with SHARP/NACO astrometry to derive improved three-dimensional stellar orbits for six of these "S stars" in the central 0 5. Their orientations in space appear random. Their orbital planes are not co-aligned with those of the two disks of massive young stars 1''-10'' from Sgr A*. We can thus exclude the hypothesis that the S stars as a group inhabit the inner regions of these disks. They also cannot have been located/formed in these disks and then migrated inward within their planes. From the combination of their normal rotation and random orbital orientations, we conclude that the S stars were most likely brought into the central light-month by strong individual scattering events. The updated estimate of distance to the Galactic center from the S2 orbit fit is R 0 = 7.62 ± 0.32 kpc, resulting in a central mass value of (3.61 ± 0.32) × 10 6 M ☉ . We happened to catch two smaller flaring events from Sgr A* during our spectral observations. The 1.7-2.45 μm spectral energy distributions of these flares are fit by a featureless, "red" power law of spectral index α' = -4 ± 1 ( S ν ~ ν ). The observed spectral slope is in good agreement with synchrotron models in which the infrared emission comes from accelerated, nonthermal, high-energy electrons in a radiatively inefficient accretion flow in the central R ~ 10 R S region.

Cited by

• An Update on Monitoring Stellar Orbits in the Galactic Center
• Optical appearance of regularized compact objects without an exterior photon sphere
• The dynamics of S-stars and G-sources orbiting a supermassive compact object made of fermionic dark matter
• Polarimetry and astrometry of NIR flares as event horizon scale, dynamical probes for the mass of Sgr A*
• The Complex Kinematics of the Young Stars Orbiting the Supermassive Black Hole in the Galactic Center Can Be Explained by the Presence of an Intermediate-mass Companion of Sgr A*
• First Sagittarius A* Event Horizon Telescope Results. VI. Testing the Black Hole Metric
• Orbital dynamics and precession in magnetized Kerr spacetime
• Milky Way evolution on a human timescale
• Constraining Dark Photon Dark Matter with Radio Silence from Soliton Mergers around Supermassive Black Holes
• Huge entropy production inside black holes
• Optical Phenomena in a Non-Commutative Kalb-Ramond Black Hole Spacetime
• VISTA Variables in the Via Lactea (VVV): The public ESO near-IR variability survey of the Milky Way
• S-stars motion around relativistic compact object Sgr A*
• Thermomagnetic Ettingshausen-Nernst effect in tachocline, magnetic reconnection phenomenon in lower layers, axion mechanism of solar luminosity variations, coronal heating problem solution and mechanism of ADM variations around BH
• Influence of the cosmological constant on gravitational lensing in small systems
• Radio and X-ray images of the SNR G18.8+0.3 interacting with molecular clouds
• Stellar Remnants in Galactic Nuclei: Mass Segregation
• Flaring Activity of Sagittarius A* at 43 and 22 GHz: Evidence for Expanding Hot Plasma
• Production of hypervelocity stars through encounters with stellar-mass black holes in the Galactic Centre
• The distances of supernova remnants Kes 69 and G21.5–0.9 from Hi and 13CO spectra
• Stellar and wind properties of massive stars in the central parsec of the Galaxy
• A polarized infrared flare from Sagittarius A* and the signatures of orbiting plasma hotspots
• Getting a Kick out of the Stellar Disk(s) in the Galactic Center
• On the orientation of the Sagittarius A* system
• Kerr black hole lensing for generic observers in the strong deflection limit
• The distance of the SNR Kes 75 and PWN PSR J1846-0258 system
• On the Nature of the Compact Dark Mass at the Galactic Center
• Gravitational waves from scattering of stellar-mass black holes in galactic nuclei
• The red clump absolute magnitude based on revised Hipparcos parallaxes
• Origin of the S Stars in the Galactic Center
• Investigating the age and structure of the infrared old open clusters LK 1, LK 10, FSR 1521 and FSR 1555
• Gravitational lensing by rotating naked singularities
• The old metal-poor open cluster ESO 92-SC05: accreted from a dwarf galaxy?
• Stellar Proper Motions in the Galactic Bulge from DeepHubble Space TelescopeACS WFC Photometry
• The Position of Sagittarius A*. III. Motion of the Stellar Cusp
• Extreme mass ratio inspiral rates: dependence on the massive black hole mass
• DYNAMICAL AND EVOLUTIONARY CONSTRAINTS ON THE NATURE AND ORIGIN OF HYPERVELOCITY STARS
• Primary caustics and critical points behind a Kerr black hole
• SimultaneousChandra, CSO, and VLA Observations of Sgr A*: The Nature of Flaring Activity
• Testing properties of the Galactic center black hole using stellar orbits
• The luminosities and distance scales of type II Cepheid and RR Lyrae variables
• X‐Ray Absorption Spectroscopy of the Multiphase Interstellar Medium: Oxygen and Neon Abundances
• Periapsis and gravitomagnetic precessions of stellar orbits in Kerr and Kerr–de Sitter black hole spacetimes
• Eccentric disc instability in stellar discs formed from inspiralling gas clouds in the Galactic Centre
• XHIP: An extended hipparcos compilation
• Relativistic images in Randall-Sundrum II braneworld lensing
• Perturbed stellar motions around the rotating black hole in Sgr A* for a generic orientation of its spin axis
• EVIDENCE FOR WARPED DISKS OF YOUNG STARS IN THE GALACTIC CENTER
• Measuring Distance and Properties of the Milky Way’s Central Supermassive Black Hole with Stellar Orbits
• Detection of the gravitational redshift in the orbit of the star S2 near the Galactic centre massive black hole
• Deep Images of the Galactic Center with GRAVITY
• S62 and S4711: Indications of a population of faint fast moving stars inside the S2 orbit -- S4711 on a 7.6 year orbit around Sgr~A*
• Mass distribution in the Galactic Center based on interferometric astrometry of multiple stellar orbits
• Cluster Core Dynamics in the Galactic Center
• Hypervelocity Stars: Predicting the Spectrum of Ejection Velocities
• The extreme luminosity states of Sagittarius A*
• OGLE 2004–BLG–254: a K3 III Galactic bulge giant spatially resolved by a single microlens
• Analytical Kerr black hole lensing in the weak deflection limit
• K-band polarimetry of an Sgr A* flare with a clear sub-flare structure
• Polarimetry of near-infrared flares from Sagittarius A*
• Near-infrared polarimetry setting constraints on the orbiting spot model for Sgr A* flares
• The proper motion of the Local Group galaxy IC 10
• The UKIDSS Galactic Plane Survey
• The Effect of Mass Segregation on Gravitational Wave Sources near Massive Black Holes
• The Milky Way, an Exceptionally Quiet Galaxy: Implications for the Formation of Spiral Galaxies
• X-ray hiccups from Sagittarius A* observed by XMM-Newton - The second brightest flare and three moderate flares caught in half a day
• Interferometric Measurements of Variable 340 GHz Linear Polarization in Sagittarius A*
• An analysis of infrared emission spectra from the regions near the Galactic Centre
• Adaptive optics: Observations and prospects for studies of active Galactic Nuclei
• STRONG FIELD EFFECTS ON PULSAR ARRIVAL TIMES: CIRCULAR ORBITS AND EQUATORIAL BEAMS
• TIDAL BREAKUP OF BINARY STARS AT THE GALACTIC CENTER AND ITS CONSEQUENCES
• THE FORMATION AND EVOLUTION OF YOUNG LOW-MASS STARS WITHIN HALOS WITH HIGH CONCENTRATION OF DARK MATTER PARTICLES
• The mid-infrared colours of Galactic bulge, disc and Magellanic planetary nebulae
• BINARY DISRUPTION BY MASSIVE BLACK HOLES: HYPERVELOCITY STARS, S STARS, AND TIDAL DISRUPTION EVENTS
• The Galactic Center massive black hole and nuclear star cluster
• Quasi-periodic flares from star-accretion-disc collisions
• The Eddington factor as the key to understand the winds of the most massive stars. Evidence for a Γ-dependence of Wolf-Rayet type mass loss
• Mass models of NGC 6624 without an intermediate-mass black hole
• DYNAMICAL EVOLUTION OF THE YOUNG STARS IN THE GALACTIC CENTER:N-BODY SIMULATIONS OF THE S-STARS
• Calculation of the local standard of rest from 20574 local stars in the New Hipparcos Reduction with known radial velocities
• On the Nature of the Fast-Moving Star S2 in the Galactic Center
• Limits on additional planetary companions to OGLE 2005-BLG-390L
• Polarized NIR and X-ray flares from Sagittarius A*
• Compact mid-IR sources east of Galactic Center source IRS5
• Gravitational lensing and frame dragging of light in the Kerr–Newman and the Kerr–Newman (anti) de Sitter black hole spacetimes
• Locating the very high energy source in the Galactic Centre with milliarcsecond accuracy
• Forming Circumnuclear Disks and Rings in Galactic Nuclei: A Competition Between Supermassive Black Hole and Nuclear Star Cluster
• Star clusters around recoiled black holes in the Milky Way halo
• The physics of the relativistic counter-streaming instability that drives mass inflation inside black holes
• The Milky Way’s Supermassive Black Hole: How Good a Case Is It?
• Absorption Line Survey of H ⁺₃ toward the Galactic Center Sources. II. Eight Infrared Sources within 30 pc of the Galactic Center
• BLACK HOLE AURORA POWERED BY A ROTATING BLACK HOLE
• Kinematics of the old stellar population at the Galactic centre
• A 600 Minute Near-Infrared Light Curve of Sagittarius A*
• Resolving the Galactic ridge X-ray background
• Evolution of Star Clusters near the Galactic Center: Fully Self‐ConsistentN‐Body Simulations
• Gravitational lensing in black-bounce spacetimes
• Discovery of optical emission from the supernova remnant G 32.8-0.1 (Kes 78)
• Dark-matter-like solutions to Einstein’s unified field equations
• Relativistic images of Schwarzschild black hole lensing
• First VLTI infrared spectro-interferometry on GCIRS 7
• Gravitational lensing of supernova neutrinos
• Our Peculiar Motion Away from the Local Void
• GRAVITATIONAL LENSING OF STARS ORBITING THE MASSIVE BLACK HOLE IN THE GALACTIC CENTER
• Constraints on the Galactic Centre environment from Gaia hyper-velocity stars
• Spectroscopic Detection of a Cusp of Late-type Stars around the Central Black Hole in the Milky Way
• Diffraction-limited Imaging Spectroscopy of the Sagittarius A* Region Using OSIRIS, a New Keck Instrument
• Sagittarius A* [wikipedia]

Related

• Massive Young Stars in the Galactic Center
• The Center of the Milky Way from Radio to X-rays
• The Galactic Center as a Paradigm for Low Luminosity Nuclei? The K-band identification of the DSO/G2 source from VLT and Keck data
• Detection of an excess of young stars in the Galactic center Sagittarius B1 region
• 2 micron Spectroscopy within 0.3 arcseconds of SgrA*