A polarised infrared flare from Sagittarius A* and the signatures of orbiting plasma hotspots

Abstract

In this article we summarise and discuss the infrared, radio, and X-ray emission from the supermassive black hole in the Galactic Centre, SgrA*. We include new results from near-infrared polarimetric imaging observations obtained on May 31st, 2006. In that night, a strong flare in Ks band (2.08 microns) reaching top fluxes of ~16 mJy could be observed. This flare was highly polarised (up to ~40%) and showed clear sub-structure on a time scale of 15 minutes, including a swing in the polarisation angle of about 70 degrees. For the first time we were able to observe both polarised flux and short-time variability, with high significance in the same flare event. This result adds decisive information to the puzzle of the SgrA* activity. The observed polarisation angle during the flare peak is the same as observed in two events in 2004 and 2005. Our observations strongly support the dynamical emission model of a decaying plasma hotspot orbiting SgrA* on a relativistic orbit. The observed polarisation parameters and their variability with time might allow to constrain the orientation of accretion disc and spin axis with respect to the Galaxy.

arXiv comment9 pages, 8 figures, accepted for publication in MNRAS

References in corpus (32)

• Chandra X-ray Spectroscopic Imaging of Sgr A* and the Central Parsec of the Galaxy
• Near-infrared flares from accreting gas around the supermassive black hole at the Galactic Centre
• SINFONI in the Galactic Center: young stars and IR flares in the central light month
• Rapid X-ray flaring from the direction of the supermassive black hole at the Galactic Centre
• The Supermassive Black Hole at the Galactic Center
• SINFONI - Integral Field Spectroscopy at 50 milli-arcsecond resolution with the ESO VLT
• Magnetically Driven Accretion Flows in the Kerr Metric I: Models and Overall Structure
• Variable Infrared Emission from the Supermassive Black Hole at the Center of the Milky Way
• Interferometric Detection of Linear Polarization from Sagittarius A* at 230 GHz
• Imaging Optically-Thin Hot Spots Near the Black Hole Horizon of Sgr A* at Radio and Near-Infrared Wavelengths
• The Nature of the 10 Kilosecond X-ray Flare in Sgr A*
• Interferometric Measurements of Variable 340 GHz Linear Polarization in Sagittarius A*
• Polarimetry of near-infrared flares from Sagittarius A*
• On The Nature of the Variable Infrared Emission from Sgr A*
• A Multi-Wavelength Study of Sgr A*: The Role of Near-IR Flares in Production of X-ray, Soft $\gamma$-ray and Sub-millimeter Emission
• X-ray flares reveal mass and angular momentum of the Galactic Center black hole
• The First Laser Guide Star Adaptive Optics Observations of the Galactic Center: Sgr A*'s Infrared Color and the Extended Red Emission in its Vicinity
• The Flare Activity of SgrA*; New Coordinated mm to X-Ray Observations
• A New X-Ray Flare from the Galactic Nucleus Detected with the XMM-Newton Photon Imaging Cameras
• Light Curves from an MHD Simulation of a Black Hole Accretion Disk
• Variations in the spectral slope of Sgr A* during a NIR flare
• Detection of Circular Polarization in the Galactic Center Black Hole Candidate Sagittarius A*
• Variable Linear Polarization from Sagittarius A*: Evidence for a Hot Turbulent Accretion Flow
• The Rotation Measure and 3.5mm Polarization of Sgr A*
• The Linear Polarization of Sagittarius A* I. VLA Spectro-polarimetry at 4.8 and 8.4 GHz
• Repeated X-ray Flaring Activity in Sagittarius A*
• X-ray flares from Sgr A*: star-disk interactions?
• Intra-Day Variation of Sagittarius A* at Short Millimeter Wavelengths
• A dual emission mechanism in Sgr A*/L' ?
• Diffraction Limited Imaging Spectroscopy of the SgrA* Region using OSIRIS, a new Keck Instrument
• Detection of the Sgr A* activity at 3.8 and 4.8 microns with NACO
• Linear and Circular Polarization from Sagittarius A* and M81*

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