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Description
We present results from three world-wide campaigns that resulted in the detections of two single-chord and one multi-chord stellar occultations by the plutino object (84922) 2003 VS_2_. From the single-chord occultations in 2013 and 2014 we obtained accurate astrometric positions for the object, while from the multi-chord occultation on 2014 November 7, we obtained the parameters of the best-fitting ellipse to the limb of the body at the time of occultation. We also obtained short-term photometry data for the body in order to derive its rotational phase during the occultation. The rotational light curve present a peak-to-peak amplitude of 0.141+/-0.009 mag. This allows us to reconstruct the 3D shape of the body, with principal semi-axes of a=313.8+/-7.1 km, b=265.5_-9.8_^+8.8^ km, and c=247.3_-43.6_^+26.6^ km, which is not consistent with a Jacobi triaxial equilibrium figure. The derived spherical volume equivalent diameter of 548.3_-44.6_^+29.5^ km is about 5% larger than the radiometric diameter of 2003 VS_2_ derived from Herschel data of 523+/-35 km, but still compatible with it within error bars. From those results we can also derive the geometric albedo (0.123_-0.014_^+0.015^) and, under the assumption that the object is a Maclaurin spheroid, the density {rho}=1400_-300_^+1000^ for the plutino. The disappearances and reappearances of the star during the occultations do not show any compelling evidence for a global atmosphere considering a pressure upper limit of about 1 microbar for a pure nitrogen atmosphere, nor secondary features (e.g., rings or satellite) around the main body.
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