We report the discovery of mid-infrared excess emission in the young object RZ Psc. The excess constitutes ∼8% of its L bol and is well fit by a single 500 K blackbody, implying a dust-free region within ∼0.7 AU for optically thick dust. The object displays dust obscuration events (UXOR behaviour) on a time scale that suggests dusty material on orbits of ∼0.5 AU. We also report a 12.4-year cyclical photometric variability that can be interpreted as caused by perturbations in the dust distribution. The system is characterized by a high inclination, marginal extinction (during bright photometric states), a single temperature for the warm dust, and an age estimate that puts the star beyond the formation stage. We propose that the dust occultation events present a dynamical view of an active asteroid belt whose collisional products sporadically obscure the central star.

Results of U BV RIJHKLM photometry and V RI polarimetry of a young star RW Aur A observed during unprecedented long and deep (up to ∆V ≈ 5 mag) dimming events in 2010-11 and 2014-18 are presented. The polarization degree p of RW Aur A at this period has reached 30 per cent in the I band. As in the case of UX Ori type stars (UXORs), the so-called 'bluing effect' in the colour-magnitude V versus V − R c , V − I c diagrams of the star and a strong anticorrelation between p and brightness were observed. But the duration and the amplitude of the eclipses as well as the value and orientation of polarization vector in our case differ significantly from that of UXORs. We concluded that the dimmings of RW Aur A occurred due to eclipses of the star and inner regions of its disc by the axisymmetric dust structure located above the disc and created by the disc wind. Taking into account both scattering and absorption of stellar light by the circumstellar dust, we explain some features of the light curve and the polarization degree -magnitude dependence. We found that near the period of minimal brightness mass-loss rate of the dusty wind was > 10 −9 M ⊙ yr −1 .

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