SIMBAD references

Aims. We aim to clarify the origin of the multiple jet features emanating from the binary protostar SVS 13A (=VLA4A/VLA4B).
Methods. We used the Plateau de Bure Interferometer to map at 0.3-0.8'' (∼70-190au) dust emission at 1.4mm, CO(2-1), SiO(5-4), SO(6₅-5₄). Revised proper motions for VLA4A/4B and jet wiggling models are computed to clarify their respective contribution.
Results. VLA4A shows compact dust emission suggestive of a disk <50au, and is the hot corino source, while CO/SiO/SO counterparts to the small-scale H₂ jet originate from VLA4B and reveal the jet variable velocity structure. This jet exhibits ∼3'' wiggling consistent with orbital motion around a yet undetected ∼20-30 au companion to VLA4B, or jet precession. Jet wiggling combined with velocity variability can explain the large apparent angular momentum in CO bullets. We also uncover a synchronicity between CO jet bullets and knots in the HH7-11 chain demonstrating that they trace two distinct jets. Their ∼300yr twin outburst period may be triggered by close perihelion approach of VLA4A in an eccentric orbit around VLA4B. A third jet is tentatively seen at PA∼0°.
Conclusions. SVS13 A harbors at least 2 and possibly 3 distinct jet sources. The CO and HH7-11 jets are launched from quasi-coplanar disks, separated by 20-70 au. Their synchronous major events every 300yr favor external triggering by close binary interactions, a scenario also invoked for FU Or outbursts.