%0 Journal Article %T Sgr B2 hard X-ray emission with INTEGRAL after 2009: still detectable? %+ Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) %A Kuznetsova, Ekaterina %A Krivonos, Roman %A Lutovinov, Alexander %A Clavel, Maïca %< avec comité de lecture %@ 0035-8711 %J Monthly Notices of the Royal Astronomical Society %I Oxford University Press (OUP): Policy P - Oxford Open Option A %V 509 %P 1605-1613 %8 2022 %D 2022 %Z 2110.07401 %Z 2022MNRAS.509.1605K %R 10.1093/mnras/stab3004 %K ISM: clouds %K Galaxy: centre %K X-rays: individual (Sgr B2) %K Astrophysics - High Energy Astrophysical Phenomena %Z Sciences of the Universe [physics]Journal articles %X The molecular cloud Sgr B2 is a natural Compton mirror in the Central Molecular Zone. It is believed that the observed fading of the Sgr B2 X-ray emission in continuum and the Fe Kα 6.4 keV line indicates past X-ray flare activity of the supermassive black hole Sgr A. Sgr B2 was investigated by the INTEGRAL observatory in the hard X-ray in 2003-2009, showing clear decay of its hard X-ray emission. In this work, we present a long-term time evolution of the Sgr B2 hard X-ray continuum after 2009, associated with the hard X-ray source IGR J17475-2822 as observed by INTEGRAL. The 30-80 keV sky maps, obtained in 2009-2019, demonstrate a significant excess spatially consistent with IGR J17475-2822. The observed 2003-2019 light curve of IGR J17475-2822 is characterized by a linear decrease by a factor of ~2 until 2011, after which it reaches a constant level of ~1 mCrab. The source spectrum above 17 keV is consistent with a power-law model with Γ = 1.4 and a high-energy cut-off at ~43 keV. The Sgr B2 residual emission after ~2011 shows a good correspondence with models of X-ray emission due to the irradiation of the molecular gas by hard X-rays and low-energy cosmic ray ions. We discuss the possible origin of the residual Sgr B2 emission after 2011 within these models, including theoretically predicted multiply scattered emission. %G English %2 https://insu.hal.science/insu-03705390/document %2 https://insu.hal.science/insu-03705390/file/stab3004.pdf %L insu-03705390 %U https://insu.hal.science/insu-03705390 %~ INSU %~ METEO %~ UNIV-SAVOIE %~ UGA %~ CNRS %~ CNES %~ OSUG %~ IPAG %~ INRAE %~ UGA-EPE %~ RESEAU-EAU