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arXiv · 1504.05197

The inner environment of Z~CMa: High-Contrast Imaging Polarimetry with NaCo

H. Canovas·S. Perez·C. Dougados·J. de Boer·F. Ménard·S. Casassus·M. R. Schreiber·L. A. Cieza·C. Caceres·J. H. Girard
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Abstract

Context. Z\,CMa is a binary composed of an embedded Herbig Be and an FU Ori class star separated by $\sim100$ au. Observational evidence indicate a complex environment in which each star has a circumstellar disk and drives a jet, and the whole system is embedded in a large dusty envelope. Aims. We aim to probe the circumbinary environment of Z\,CMa in the inner 400 au in scattered light. Methods. We use high contrast imaging polarimetry with VLT/NaCo at $H$ and $K_s$ bands. Results. The central binary is resolved in both bands. The polarized images show three bright and complex structures: a common dust envelope, a sharp extended feature previously reported in direct light, and an intriguing bright clump located $0\farcs3$ south of the binary, which appears spatially connected to the sharp extended feature. Conclusions.We detect orbital motion when compared to previous observations, and report a new outburst driven by the Herbig star. Our observations reveal the complex inner environment of Z\,CMa with unprecedented detail and contrast.

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H. Canovas, S. Perez, C. Dougados, J. de Boer, F. Ménard, S. Casassus, M. R. Schreiber, L. A. Cieza, C. Caceres, J. H. Girard. 2015-04-20. The inner environment of Z~CMa: High-Contrast Imaging Polarimetry with NaCo. https://doi.org/10.1051/0004-6361%2F201526134

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