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Sinfoni in the galactic center : Young stars and infrared flares in the central light-month
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
A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way
Ten years of high-resolution astrometric imaging allow us to trace two-thirds of the orbit of the star currently closest to the compact radio source (and massive black-hole candidate) Sagittarius A* and show that the star is on a bound, highly elliptical keplerian orbit around Sgr A*.
Near-infrared flares from accreting gas around the supermassive black hole at the Galactic Centre
High-resolution infrared observations of Sagittarius A* reveal ‘quiescent’ emission and several flares, and traces very energetic electrons or moderately hot gas within the innermost accretion region.
The Shortest-Known–Period Star Orbiting Our Galaxy’s Supermassive Black Hole
S0-102, a star orbiting the authors' Galaxy’s supermassive black hole, is detected, doubling the number of known stars with full phase coverage and periods of less than 20 years and providing the opportunity to resolve degeneracies in the parameters describing the central gravitational potential and to test Einstein's theory of general relativity in an unexplored regime.
Earthward flow bursts, auroral streamers, and small expansions
Earthward flow bursts associated with small auroral expansions, including pseudobreakups, and auroral streamers are studied by using Geotail plasma and magnetic field data and Polar ultraviolet
Relativistic redshift of the star S0-2 orbiting the Galactic Center supermassive black hole
A combination of special relativistic and gravitational redshift is detected, quantified using the redshift parameter ϒ, which is consistent with general relativity and excludes a Newtonian model with a statistical significance of 5σ.
Polarimetry of near-infrared flares from Sagittarius A*
Context. We report new polarization measurements of the variable near-infrared emission of the SgrA* counterpart associated with the massive 3–$4\times10^6$ $M_{\odot}$ Black Hole at the Galactic
The Universe under the Microscope: Astrophysics at High Angular Resolution
High angular resolution techniques at infrared and centimeter to millimeter wavelengths have become of ever increasing importance for astrophysical research in the past decade. They have led to
The near-infrared spectral index of Sagittarius A* derived from Ks- and H-band flare statistics
Context. The near-infrared (NIR) counterpart of Sagittarius A* (SgrA*) at the position of the 4 x 10(6) M(circle dot) supermassive black hole at the center of the Milky Way has strongly varying flux
Rapid flux transport in the central plasma sheet
On the basis of several years of Geotail data we performed a comprehensive statistical analysis of rapid convective transport in the neartail and midtail central plasma sheet. We chose a new approach