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AGB stars are one of the main sources of dust production in the Galaxy.However, it is not clear what this process looks like and where the dust iscondensing in the circumstellar environment. By characterizing the location ofthe dust and the molecules in the close environment of an AGB star, we aim toachieve a better understanding the history of the dust formation process. Weobserved the carbon star R Scl with the VLTI-MATISSE instrument in L- andN-bands. The high angular resolution of the VLTI observations, combined with alarge uv-plane coverage allowed us to use image reconstruction methods. Toconstrain the dust and molecules' location, we used two different methods: MIRAimage reconstruction and the 1D code RHAPSODY. We found evidence of C2H2 andHCN molecules between 1 and 3.4 Rstar which is much closer to the star than thelocation of the dust (between 3.8 and 17.0 Rstar). We also estimated amass-loss rate of 1.2+-0.4x10-6 Msun per yr. In the meantime, we confirmed thepreviously published characteristics of a thin dust shell, composed ofamorphous carbon (amC) and silicon carbide (SiC). However, no clear SiC featurehas been detected in the MATISSE visibilities. This might be caused bymolecular absorption that can affect the shape of the SiC band at 11.3 micron.The appearance of the molecular shells is in good agreement with predictionsfrom dynamical atmosphere models. For the first time, we co-located dust andmolecules in the environment of an AGB star. We confirm that the molecules arelocated closer to the star than the dust. The MIRA images unveil the presenceof a clumpy environment in the fuzzy emission region beyond 4.0 Rstar.Furthermore, with the available dynamic range and angular resolution, we didnot detect the presence of a binary companion. Additional observationscombining MATISSE and SAM-VISIR instrument should enable this detection infuture studies.

Locating dust and molecules in the inner circumstellar environment of R~Sculptoris with MATISSE