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A growing number of transient X-ray obscuration events in type I AGN suggestthat our line-of-sight to the central engine is not always free. Multiple X-rayobscuration events have been reported in the nearby Seyfert 1.5 galaxy NGC 3227from 2000 to 2016. In late 2019, another X-ray obscuration event was identifiedwith Swift. Two coordinated target-of-opportunity observations with XMM-Newton,NuSTAR, and HST/COS were triggered in Nov. and Dec. 2019 to study thisobscuration event. For each observation, we analyze the time-averaged X-rayspectra. We perform photoionization modeling with the SPEX code, which allowsus to constrain the intrinsic continuum simultaneously with variousphotoionized absorption and emission components. Similar to previous transientX-ray obscuration events in NGC 3227, the one caught in late 2019 isshort-lived (less than five months). If the obscurer has only one photoionizedcomponent, the two X-ray observations in late 2019 cannot be explained by thesame obscurer that responds to the varying ionizing continuum. Due to theunknown geometry of the obscurer, its number density and distance to the blackhole cannot be well constrained. The inferred distance covers at least twoorders of magnitude, from the BLR to the dusty torus. Unlike some other X-rayobscuration events in Seyfert galaxies like NGC 5548 and NGC 3783, no prominentblueshifted broad absorption troughs were found in the 2019 HST/COS spectra ofNGC 3227 when compared with archival UV spectra. This might be explained if theX-ray obscurer does not intercept our line of sight to (a significant portionof) the UV emitting region. It is not straightforward to understand the varietyof the observational differences in the X-ray obscuration events observed sofar. Future observations with high-quality data are needed to unveil the natureof the X-ray obscuration events. [shortend for arXiv]

Transient obscuration event captured in NGC 3227 III. Photoionization modeling of the X-ray obscuration event in 2019