The gas streamer G1-2-3 in the Galactic Center
S. Gillessen, F. Eisenhauer, J. Cuadra, R. Genzel, D. Calderon, S. Joharle, T. Piran, D. C. Ribeiro, C. M. P. Russell, M. Sadun Bordoni, A. Burkert, G. Bourdarot, A. Drescher, F. Mang, T. Ott, G. Agapito, A. Agudo Berbel, A. Baruffolo, M. Bonaglia, M. Black, R. Briguglio, Y. Cao, L. Carbonaro, G. Cresci, Y. Dallilar, R. Davies, M. Deysenroth, I. Di Antonio, A. Di Cianno, G. Di Rico, D. Doelman, M. Dolci, S. Esposito, D. Fantinel, D. Ferruzzi, H. Feuchtgruber, N. M. Förster Schreiber, A. M. Glauser, P. Grani, M. Hartl, D. Henry, H. Huber, C. Keller, M. Kenworthy, K. Kravchenko, J. Lightfoot, D. Lunney, D. Lutz, M. Macintosh, F. Mannucci, D. Pearson, A. Puglisi, S. Rabien, C. Rau, A. Riccardi, B. Salasnich, T. Shimizu, F. Snik, E. Sturm, L. J. Tacconi, W. Taylor, A. Valentini, C. Waring, M. Xompero
公開日: 2025/10/1
Abstract
The black hole in the Galactic Center, Sgr A*, is prototypical for ultra-low-fed galactic nuclei. The discovery of a hand-full of gas clumps in the realm of a few Earth masses in its immediate vicinity provides a gas reservoir sufficient to power Sgr A*. In particular, the gas cloud G2 is of interest due to its extreme orbit, on which it passed at a pericenter distance of around 100 AU and notably lost kinetic energy during the fly-by due to the interaction with the black hole accretion flow. 13 years prior to G2, a resembling gas cloud called G1, passed Sgr A* on a similar orbit. The origin of G2 remained a topic of discussion, with models including a central (stellar) source still proposed as alternatives to pure gaseous clouds. Here, we report the orbit of a third gas clump moving again along (almost) the same orbital trace. Since the probability of finding three stars on close orbits is very small, this strongly argues against stellar-based source models. Instead, we show that the gas streamer G1-2-3 plausibly originates from the stellar wind of the massive binary star IRS16SW. This claim is substantiated by the fact that the small differences between the three orbits - the orientations of the orbital ellipses in their common plane as a function of time - are consistent with the orbital motion of IRS 16SW.