A passion for astrophysics led a researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC) to specialize in the study of protostellar jets, powerful streams of material ejected from the disk/star system at speeds of hundreds of kilometers per second. These phenomena, whose link to star formation was demonstrated in the 1980s, remain a subject of research to understand their origin and role in the formation of stars and planets.
The doctoral thesis focused on the young stellar object SVS 13, located in the star-forming region NGC 1333. This binary system, discovered in the 2000s, is powered by the protostar SVS 13, known for generating the 'Herbig-Haro' objects 7-11. In 1990, SVS 13 experienced an outburst that increased its luminosity, making it an ideal case for studying the dynamics of protostellar ejections and their relationship with these outbursts.
Observations from the ALMA telescope, noted for their high resolution and sensitivity, revealed a series of rings in the velocity channels of SVS 13, structures unprecedented in this type of object. These images, comparable to a medical tomography, showed sequences of rings whose shape and position changed smoothly, tracing elongated shells with increased brightness 'knots', typical of jets.
The physical interpretation of these observations was achieved through an analytical bow shock model, developed by collaborators at IAA-CSIC. This model explains the formation of 'internal working surfaces' and 'bow shocks' from the interaction between a supersonic jet of variable velocity and its environment. The jet's 'knots' manifest as compressed material, and the bow shock resembles a ship's wake.
The modeling has helped understand how jets inject mass and momentum into the environment, crucial for comprehending star formation. Furthermore, a birth date has been assigned to each 'knot', with one coinciding with the outburst of SVS 13 in 1990. This suggests that outbursts are linked to changes in the jet's ejection velocity, preserving a history of stellar formation.
These results, published in Nature Astronomy, form the core of the doctoral thesis. Future research will focus on monitoring the brightness of SVS 13, predicting a possible increase in the coming years based on knot formation approximately every 35 years, which would significantly strengthen the current interpretation.
The researcher, a Physics graduate from the University of Córdoba, is completing his doctorate at IAA-CSIC, focusing on the study of jets during stellar birth using ALMA observations and supersonic shock models.
