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Related papers: S62 on a 9.9 yr Orbit around SgrA*

200 papers

The hierarchical nature of galaxy formation suggests that a supermassive black hole binary could exist in our galactic center. We propose a new approach to constraining the possible orbital configuration of such a binary companion to the…

Astrophysics of Galaxies · Physics 2025-07-11 Smadar Naoz , Clifford M. Will , Enrico Ramirez-Ruiz , Aurelien Hees , Andrea M. Ghez , Tuan Do

We present new proper motion measurements and simultaneous orbital solutions for three newly identified (S0-16, S0-19, and S0-20) and four previously known (S0-1, S0-2, S0-4, and S0-5) stars at the Galactic Center. This analysis pinpoints…

Astrophysics · Physics 2009-02-18 A. M. Ghez , S. Salim , S. D. Hornstein , A. Tanner , J. R. Lu , M. Morris , E. E. Becklin , G. Duchene

The Galactic Center hosts a rotating disk of young stars between 0.05 and 0.5 pc of Sgr A*. The ``S-stars'' at a distance $<0.04$ pc, however, are on eccentric orbits with nearly isotropically distributed inclinations. The dynamical origin…

Astrophysics of Galaxies · Physics 2024-11-14 Tatsuya Akiba , Smadar Naoz , Ann-Marie Madigan

We report measurements with the Very Long Baseline Array of the proper motion of Sgr A* relative to two extragalactic radio sources spanning 18 years. The apparent motion of Sgr A* is -6.411 +/- 0.008 mas/yr along the Galactic plane and…

Astrophysics of Galaxies · Physics 2020-04-01 M. J. Reid , A. Brunthaler

The polarized mm/sub-mm radiation from Sgr A* is apparently produced by a Keplerian structure whose peak emission occurs within several Schwarzschild radii (r_S=2GM/c^2) of the black hole. The Chandra X-ray counterpart, if confirmed, is…

Astrophysics · Physics 2009-11-06 Fulvio Melia , Benjamin C. Bromley , Siming Liu , Christopher , K. Walker

We report 75 milli-arcsec resolution, near-IR imaging spectroscopy within the central 30 light days of the Galactic Center [...]. To a limiting magnitude of K~16, 9 of 10 stars in the central 0.4 arcsec, and 13 of 17 stars out to 0.7 arcsec…

The gravitational lensing of a finite star moving around a rotating Kerr black hole has been numerically calculated. Calculations for the direct image of the star and for the first and second light echoes have been performed for the star…

High Energy Astrophysical Phenomena · Physics 2018-02-06 V. I. Dokuchaev , N. O. Nazarova

We use 23 years of astrometric and radial velocity data on the orbit of the star S0-2 to constrain a hypothetical intermediate-mass black hole orbiting the massive black hole Sgr A* at the Galactic center. The data place upper limits on…

Astrophysics of Galaxies · Physics 2023-12-13 Clifford M. Will , Smadar Naoz , Aurélien Hees , Alexandria Tucker , Eric Zhang , Tuan Do , Andrea Ghez

Time-resolved X-ray spectroscopy has been obtained for the narrow line Seyfert galaxy Mrk766 from XMM-Newton observations. We present analysis in the energy-time plane of EPIC pn data in the 4-8 keV band with energy resolution R~50. A…

Astrophysics · Physics 2009-11-11 T. J. Turner , L. Miller , I. M. George , J. N. Reeves

Precision Doppler velocity measurements from the 3.9--m Anglo-Australian Telescope reveal a planet with a 6 year period orbiting the G5 dwarf HD 70642. The a = 3.3 AU orbit has a low eccentricity (e = 0.1), and the minimum (\msini) mass of…

We present timing analysis of the accretion powered pulsar SXP 1062, based on the observations of \textit{Swift}, \textit{XMM-Newton} and \textit{Chandra} satellites covering a time span of about 2 years. We obtain a phase coherent timing…

High Energy Astrophysical Phenomena · Physics 2017-09-06 M. M. Serim , S. Sahiner , D. Cerri-Serim , S. C. Inam , A. Baykal

We summarize basic observational results on Sagittarius~A* obtained from the radio, infrared and X-ray domain. Infrared observations have revealed that a dusty S-cluster object (DSO/G2) passes by SgrA*, the central super-massive black hole…

We confirm the planetary nature of Kepler-539b (aka Kepler object of interest K00372.01), a giant transiting exoplanet orbiting a solar-analogue G2 V star. The mass of Kepler-539b was accurately derived thanks to a series of precise radial…

Earth and Planetary Astrophysics · Physics 2016-06-01 L. Mancini , J. Lillo-Box , J. Southworth , L. Borsato , D. Gandolfi , S. Ciceri , D. Barrado , R. Brahm , Th. Henning

The spin of the massive black hole (BH) at the center of the Milky Way, SgrA$^*$, has been poorly constrained so far. We place an upper limit on the spin of SgrA$^*$ based on the spatial distribution of the S-stars, which are arranged in…

Astrophysics of Galaxies · Physics 2020-10-07 Giacomo Fragione , Abraham Loeb

Despite the huge improvements guaranteed by future GRAVITY observations of the S0-2 star, these will not be able to unveil the fundamental nature, whether black hole or wormhole, of the central supermassive object. Nevertheless, observing…

Astrophysics of Galaxies · Physics 2022-03-09 Riccardo Della Monica , Ivan de Martino

In the past three decades, many stars orbiting about the supermassive black hole (SMBH) at the Galactic Centre (Sgr A*) were identified. Their orbital nature can give stringent constraints for the mass of the SMBH. In particular, the star…

Astrophysics of Galaxies · Physics 2022-10-24 Man Ho Chan , Chak Man Lee , Chi Wai Yu

We show that the time-dependent Doppler effect should induce measureable deviations of the time history of the projected orbit of a star around the supermassive black hole in the Galactic center (SgrA*) from the expected Keplerian history.…

Astrophysics · Physics 2007-05-23 Abraham Loeb

Over a two year period (1995-1997), we have conducted a diffraction-limited imaging study at 2.2 microns of the inner 6"x6" of the Galaxy's central stellar cluster using the Keck 10-m telescope. The K band images obtained reveal a large…

Astrophysics · Physics 2009-10-30 A. M. Ghez , B. L. Klein , M. Morris , E. E. Becklin

The gas cloud G2 falling toward Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, is supposed to provide valuable information on the physics of accretion flows and the environment of the black hole. We…

High Energy Astrophysical Phenomena · Physics 2015-04-22 J. -H. Park , S. Trippe , T. P. Krichbaum , J. -Y. Kim , M. Kino , A. Bertarini , M. Bremer , P. de Vicente