Details

Autor(en) / Beteiligte

• Bauböck, M.
• Dexter, J.
• Abuter, R.
• Amorim, A.
• Berger, J. P.
• Bonnet, H.
• Brandner, W.
• Clénet, Y.
• Coudé du Foresto, V.
• de Zeeuw, P. T.
• Duvert, G.
• Eckart, A.
• Eisenhauer, F.
• Förster Schreiber, N. M.
• Gao, F.
• Garcia, P.
• Gendron, E.
• Genzel, R.
• Gerhard, O.
• Gillessen, S.
• Habibi, M.
• Haubois, X.
• Henning, T.
• Hippler, S.
• Horrobin, M.
• Jiménez-Rosales, A.
• Jocou, L.
• Kervella, P.
• Lacour, S.
• Lapeyrère, V.
• Le Bouquin, J.-B.
• Léna, P.
• Ott, T.
• Paumard, T.
• Perraut, K.
• Perrin, G.
• Pfuhl, O.
• Rabien, S.
• Rodriguez Coira, G.
• Rousset, G.
• Scheithauer, S.
• Stadler, J.
• Sternberg, A.
• Straub, O.
• Straubmeier, C.
• Sturm, E.
• Tacconi, L. J.
• Vincent, F.
• von Fellenberg, S.
• Waisberg, I.
• Widmann, F.
• Wieprecht, E.
• Wiezorrek, E.
• Woillez, J.
• Yazici, S.

Titel

Modeling the orbital motion of Sgr A’s near-infrared flares

Ist Teil von

• Astronomy and astrophysics (Berlin), 2020-03, Vol.635, p.A143

Ort / Verlag

Heidelberg: EDP Sciences

Erscheinungsjahr

2020

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Infrared observations of Sgr A* probe the region close to the event horizon of the black hole at the Galactic center. These observations can constrain the properties of low-luminosity accretion as well as that of the black hole itself. The GRAVITY instrument at the ESO VLTI has recently detected continuous circular relativistic motion during infrared flares which has been interpreted as orbital motion near the event horizon. Here we analyze the astrometric data from these flares, taking into account the effects of out-of-plane motion and orbital shear of material near the event horizon of the black hole. We have developed a new code to predict astrometric motion and flux variability from compact emission regions following particle orbits. Our code combines semi-analytic calculations of timelike geodesics that allow for out-of-plane or elliptical motions with ray tracing of photon trajectories to compute time-dependent images and light curves. We apply our code to the three flares observed with GRAVITY in 2018. We show that all flares are consistent with a hotspot orbiting at R  ∼ 9 gravitational radii with an inclination of i  ∼ 140°. The emitting region must be compact and less than ∼5 gravitational radii in diameter. We place a further limit on the out-of-plane motion during the flare.