Speaker
Description
We present high-angular and high-spectral resolution ALMA CO observations of the molecular jet driven by the outbursting protostar SVS 13. Thanks to the high sensitivity of these data, we are able to resolve faint shell-like structures connected to jet knots at their apex. The morphology and kinematics of these shells are in excellent agreement with predictions from an analytical bowshock model. This strongly supports the interpretation that jet knots provide a fossil record of ejection variability, further reinforced by the temporal coincidence of the most recent knot with the documented optical/IR photometric outburst of SVS 13 around 1990. These findings imply that accretion outbursts should be accompanied by changes in ejection speed, since variations in jet mass flux alone would not produce the observed internal shocks nor the observed bowshocks.
