X-ray polarization evidence for a 200-year-old flare of Sgr A*

Marin, FrédéricFrédéricMarinChurazov, EugeneEugeneChurazovKhabibullin, IldarIldarKhabibullinFERRAZZOLI, RiccardoRiccardoFERRAZZOLIDi Gesu, LauraLauraDi GesuBarnouin, ThibaultThibaultBarnouinDI MARCO, AlessandroAlessandroDI MARCOMIDDEI, RiccardoRiccardoMIDDEIVikhlinin, AlexeyAlexeyVikhlininCOSTA, ENRICOENRICOCOSTASOFFITTA, PAOLOPAOLOSOFFITTAWeisskopf, Martin C.Martin C.WeisskopfWu, KinwahKinwahWuXIE, FEIFEIXIEZane, SilviaSilviaZaneMULERI, FABIOFABIOMULERISunyaev, RashidRashidSunyaevForman, WilliamWilliamFormanKraft, RalphRalphKraftBianchi, StefanoStefanoBianchiDonnarumma, ImmacolataImmacolataDonnarummaPetrucci, Pierre-OlivierPierre-OlivierPetrucciEnoto, TeruakiTeruakiEnotoAgudo, IvánIvánAgudoANTONELLI, Lucio AngeloLucio AngeloANTONELLIBACHETTI, MatteoMatteoBACHETTIBaldini, LucaLucaBaldiniBaumgartner, Wayne H.Wayne H.BaumgartnerBellazzini, RonaldoRonaldoBellazziniBongiorno, Stephen D.Stephen D.BongiornoBonino, RaffaellaRaffaellaBoninoBrez, AlessandroAlessandroBrezBUCCIANTINI, Niccolo'Niccolo'BUCCIANTINICAPITANIO, FIAMMAFIAMMACAPITANIOCastellano, SimoneSimoneCastellanoCavazzuti, ElisabettaElisabettaCavazzutiChen, Chien-TingChien-TingChenCiprini, StefanoStefanoCipriniDE ROSA, AlessandraAlessandraDE ROSADEL MONTE, EttoreEttoreDEL MONTEDi Lalla, NiccolòNiccolòDi LallaDoroshenko, VictorVictorDoroshenkoDovčiak, MichalMichalDovčiakEhlert, Steven R.Steven R.EhlertEVANGELISTA, YURIYURIEVANGELISTAFABIANI, SergioSergioFABIANIGarcia, Javier A.Javier A.GarciaGunji, ShuichiShuichiGunjiHayashida, KiyoshiKiyoshiHayashidaHeyl, JeremyJeremyHeylIngram, AdamAdamIngramIwakiri, WataruWataruIwakiriJorstad, Svetlana G.Svetlana G.JorstadKaaret, PhilipPhilipKaaretKaras, VladimirVladimirKarasKitaguchi, TakaoTakaoKitaguchiKolodziejczak, Jeffery J.Jeffery J.KolodziejczakKrawczynski, HenricHenricKrawczynskiLA MONACA, FabioFabioLA MONACALatronico, LucaLucaLatronicoLiodakis, IoannisIoannisLiodakisMaldera, SimoneSimoneMalderaManfreda, AlbertoAlbertoManfredaMarinucci, AndreaAndreaMarinucciMarscher, Alan P.Alan P.MarscherMarshall, Herman L.Herman L.MarshallMASSARO, FrancescoFrancescoMASSAROMatt, GiorgioGiorgioMattMitsuishi, IkuyukiIkuyukiMitsuishiMizuno, TsunefumiTsunefumiMizunoNegro, MichelaMichelaNegroNg, C. -Y.C. -Y.NgO'Dell, Stephen L.Stephen L.O'DellOmodei, NicolaNicolaOmodeiOppedisano, ChiaraChiaraOppedisanoPAPITTO, ALESSANDROALESSANDROPAPITTOPavlov, George G.George G.PavlovPeirson, Abel L.Abel L.PeirsonPERRI, MatteoMatteoPERRIPesce-Rollins, MelissaMelissaPesce-RollinsPILIA, MauraMauraPILIAPOSSENTI, ANDREAANDREAPOSSENTIPoutanen, JuriJuriPoutanenPuccetti, SimonettaSimonettaPuccettiRamsey, Brian D.Brian D.RamseyRANKIN, JohnJohnRANKINRATHEESH, AJAYAJAYRATHEESHRoberts, Oliver J.Oliver J.RobertsRomani, Roger W.Roger W.RomaniSgrò, CarmeloCarmeloSgròSlane, PatrickPatrickSlaneSpandre, GloriaGloriaSpandreSwartz, DougDougSwartzTamagawa, ToruToruTamagawaTAVECCHIO, FabrizioFabrizioTAVECCHIOTaverna, RobertoRobertoTavernaTawara, YuzuruYuzuruTawaraTennant, Allyn F.Allyn F.TennantThomas, Nicholas E.Nicholas E.ThomasTOMBESI, FrancescoFrancescoTOMBESITROIS, ALESSIOALESSIOTROISTsygankov, Sergey S.Sergey S.TsygankovTurolla, RobertoRobertoTurollaVink, JaccoJaccoVink2025-02-242025-02-2420230028-0836http://hdl.handle.net/20.500.12386/36167The centre of the Milky Way Galaxy hosts a black hole with a solar mass of about 4 million (Sagittarius A* (Sgr A)) that is very quiescent at present with a luminosity many orders of magnitude below those of active galactic nuclei1. Reflection of X-rays from Sgr A* by dense gas in the Galactic Centre region offers a means to study its past flaring activity on timescales of hundreds and thousands of years2. The shape of the X-ray continuum and the strong fluorescent iron line observed from giant molecular clouds in the vicinity of Sgr A* are consistent with the reflection scenario3-5. If this interpretation is correct, the reflected continuum emission should be polarized6. Here we report observations of polarized X-ray emission in the direction of the molecular clouds in the Galactic Centre using the Imaging X-ray Polarimetry Explorer. We measure a polarization degree of 31% ± 11%, and a polarization angle of −48° ± 11°. The polarization angle is consistent with Sgr A* being the primary source of the emission, and the polarization degree implies that some 200 years ago, the X-ray luminosity of Sgr A* was briefly comparable to that of a Seyfert galaxy.STAMPAenX-ray polarization evidence for a 200-year-old flare of Sgr A*Article10.1038/s41586-023-06064-x2-s2.0-85162190611https://www.nature.com/articles/s41586-023-06064-xhttps://api.elsevier.com/content/abstract/scopus_id/851621906112023Natur.619...41MFIS/05 - ASTRONOMIA E ASTROFISICA