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We report results from multi-epoch X-ray observations of the polar-scatteredSeyfert 1 galaxy ESO 323-G77. The source exhibits remarkable spectralvariability from months to years timescales. The observed spectral variabilityis entirely due to variations of the column density of a neutral absorbertowards the intrinsic nuclear continuum. The column density is generallyCompton-thin ranging from a few times 10$^{22}$ cm$^{-2}$ to a few times10$^{23}$ cm$^{-2}$. However, one observation reveals a Compton-thick statewith column density of the order of 1.5 $\times$ 10$^{24}$ cm$^{-2}$. Theobserved variability offers a rare opportunity to study the properties of theX-ray absorber(s) in an active galaxy. We identify variable X-ray absorptionfrom two different components, namely (i) a clumpy torus whose individualclumps have a density of $\leq$ 1.7 $\times$ 10$^8$ cm$^{-3}$ and an averagecolumn density of $\sim$ 4 $\times$ 10$^{22}$ cm$^{-2}$, and (ii) the broadline region (BLR), comprising individual clouds with density of 0.1-8 $\times$10$^9$ cm$^{-3}$ and column density of 10$^{23}$-10$^{24}$ cm$^{-2}$. Thederived properties of the clumpy torus can also be used to estimate the torushalf-opening angle, which is of the order of 47 $^\circ$. We also confirm thepreviously reported detection of two highly ionized warm absorbers with outflowvelocities of 1000-4000 km s$^{-1}$. The observed outflow velocities areconsistent with the Keplerian/escape velocity at the BLR. Hence, the warmabsorbers may be tentatively identified with the warm/hot inter-cloud mediumwhich ensures that the BLR clouds are in pressure equilibrium with theirsurroundings. The BLR line-emitting clouds may well be the cold, dense clumpsof this outflow, whose warm/hot phase is likely more homogeneous, as suggestedby the lack of strong variability of the warm absorber(s) properties during ourmonitoring.

The properties of the clumpy torus and BLR in the polar-scattered Seyfert 1 galaxy ESO 323-G77 through X-ray absorption variability