| Description |
Coordinated study of flare emission from Sgr A*, the closest supermassiveblack hole, reveals information about the hydrodynamics, energetics, andaccretion behavior of matter within the innermost ten Schwarzschild radii.We propose to use the unique capability of Herschel/SPIRE and XMM in orderto characterize flare emission simultaneously at many different wavelengths,the most important of which are completely unavailable from the ground.These measurements will explore the nature of emission at the peak of thespectrum of Sgr A* and will determine the transition wavelength at which thevariable emission becomes optically thin. In particular, we will test theprediction that there will be time delay between X-ray flares and the peakemission at 250, 350, and 500 microns. We will take advantage of thecalibration stability of Herschel resulting from the L2 placement to detectSgr A* in SPIRE difference images. The proposed Herschel and XMMobservations form the cornerstone of a multi-wavelength campaign thatincludes observations in near-IR and radio wavelengths. The crosscorrelation of flare emission at multiple wavelengths will have far-reachingimplications for testing the emission mechanism of Sgr A* and forunderstanding the processes of accretion onto and outflow from the closestsupermassive black hole. Lastly, a long flux monitoring of Sgr A* withHerschel over long and nearly continuous baselines will characterize thefraction of time that Sgr A* is active in submm wavelengths and will providea legacy to unravel the key properties of the best example of alow-luminosity massive black hole. |
