Acceleration and cooling of the corona during X-ray flares from the Seyfert galaxy I Zw 1

We report on X-ray flares that were observed from the active galactic nucleus I Zwicky 1 (I Zw 1) in 2020 January by NuSTAR and XMM-Newton observatories. The spectrum is well-described a model comprised of continuum emission corona its reflection accretion disc around rapidly spinning (a > 0.94) black hole. In order to broadband spectrum, it necessary account for variation ionisation across disc. Analysis time periods before, during after reveal underlying changes associated with flaring. During flares, fraction drops significantly, consistent acceleration away find first evidence temperature 140(-20,+100)keV before 45(-9,+40)keV flares. profile iron K line reveals emissivity disc, showing be illuminated compact extending no more than 7(-2,+4)rg over but tentative expands as accelerated Once subsided, had collapsed radius 6(-2,+2)rg. rapid timescale suggests they arise within black-hole magnetosphere rather arising Comptonisation seed photons