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Recent years have seen broad observational support for the presence of aclumpy component within the circumnuclear gas around SMBHs. In the X-ray band,individual clouds can manifest themselves when they transit the line of sightto the X-ray corona, temporarily obscuring the X-ray continuum and therebyindicating the characteristics and location of these clouds. X-ray fluxmonitoring with SRG/eROSITA has revealed that in the Seyfert 1 AGN EC04570-5206, the soft X-ray flux dipped abruptly for about 10-18 months over2020-2021, only to recover and then drop a second time by early 2022. Here, weinvestigate whether these flux dips and recoveries could be associated withcloud occultation events. We complemented the eROSITA scans withmultiwavelength follow-up observations, including X-ray/UV observations withSwift, XMM-Newton, and NICER, along with ground-based optical photometric andspectroscopic observations to investigate the spectral and flux variability.XMM-Newton spectra confirm that the soft X-ray flux dips were caused bypartial-covering obscuration by two separate clouds. The 2020-2021 event wascaused by a cloud with column density near 1e22 /cm2 and a covering fractionnear 0.6. The cloud in the 2022 event had a column density near 3e23 /cm2 and acovering fraction near 0.8. The optical/UV continuum flux varied minimally andthe optical emission line spectra showed no variability in Balmer profiles orintensity. The transiting gas clouds are neutral or lowly-ionized, while thelower limits on their radial distances are commensurate with the dustsublimation zone (cloud 1) or the optical broad line region (cloud 2). Onepossible explanation is a dust-free, outflowing wind with embedded X-rayclumps. These events are the first cloud obscuration events detected in aSeyfert galaxy using eROSITA's X-ray monitoring capabilities.

eROSITA Detection of a Cloud Obscuration Event in the Seyfert AGN EC 04570-5206