Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16

A. Marinucci , F. Muleri , M. Dovciak , S. Bianchi , F. Marin (1) , G. Matt , F. Ursini , R. Middei , H. L. Marshall , L. Baldini , T. Barnouin (1) , N. Cavero Rodriguez , A. De Rosa , L. Di Gesu , D. Harper , A. Ingram , V. Karas , H. Krawczynski , G. Madejski , C. Panagiotou , P. O. Petrucci (2) , J. Podgorny (1) , S. Puccetti , F. Tombesi , A. Veledina , W. Zhang , I. Agudo , L. A. Antonelli , M. Bachetti , W. H. Baumgartner , R. Bellazzini , S. D. Bongiorno , R. Bonino , A. Brez , N. Bucciantini , F. Capitanio , S. Castellano , E. Cavazzuti , S. Ciprini , E. Costa , E. del Monte , N. Di Lalla , A. Di Marco , I. Donnarumma , V. Doroshenko , S. R. Ehlert , T. Enoto , Y. Evangelista , S. Fabiani , R. Ferrazzoli , J. A. Garcia , S. Gunji , K. Hayashida , J. Heyl , W. Iwakiri , S. G. Jorstad , T. Kitaguchi , J. J. Kolodziejczak , F. La Monaca , L. Latronico , I. Liodakis , S. Maldera , A. Manfreda , A. P. Marscher , I. Mitsuishi , T. Mizuno , C. -Y. Ng , S. L. O'Dell , N. Omodei , C. Oppedisano , A. Papitto , G. G. Pavlov , A. L. Peirson , M. Perri , M. Pesce-Rollins , M. Pilia , A. Possenti , J. Poutanen , B. D. Ramsey , J. Rankin , A. Ratheesh , R. W. Romani , C. Sgrš , P. Slane , P. Soffitta , G. Spandre , T. Tamagawa , F. Tavecchio , R. Taverna , Y. Tawara , A. F. Tennant , N. E. Thomas , A. Trois , S. S. Tsygankov , R. Turolla , J. Vink , M. C. Weisskopf , K. Wu , F. Xie , S. Zane

1 ObAS - Observatoire astronomique de Strasbourg
2 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble

We report on the first observation of a radio-quiet Active Galactic Nucleus (AGN) in polarized X-rays: the Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed at with the Imaging X-ray Polarimetry Explorer (IXPE) starting on May 14, 2022 for a net observing time of 486 ks, simultaneously with XMM-Newton (58 ks) and NuSTAR (83 ks). A polarization degree Π smaller than 4.7 per cent (at the 99 per cent confidence level) is derived in the 2-8 keV energy range, where emission is dominated by the primary component ascribed to the hot corona. The broad-band spectrum, inferred from a simultaneous fit to the IXPE, NuSTAR, and XMM-Newton data, is well reproduced by a power law with photon index Γ = 1.85 ± 0.01 and a high-energy cutoff E_C = 120 ± 15 keV. A comparison with Monte Carlo simulations shows that a lamp-post and a conical geometry of the corona are consistent with the observed upper limit, a slab geometry is allowed only if the inclination angle of the system is less than 50^○

Mots clés: galaxies: active; galaxies: Seyfert; galaxies: individual: MCG-05-23-16; polarization; Astrophysics - High Energy Astrophysical Phenomena; galaxies: active

Domaines: Planète et Univers [physics]

A. Marinucci, F. Muleri, M. Dovciak, S. Bianchi, F. Marin, et al.. Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16. Monthly Notices of the Royal Astronomical Society, 2022, 516 (4), pp.5907-5913. ⟨10.1093/mnras/stac2634⟩. ⟨insu-03794870⟩