Abstract

AbstractStar formation processes in galaxies are far from being understood. Resonance rings of star formation are a common phenomenon of early-type barred spiral galaxies. Most rings are regions of enhanced star formation via gas cloud collisions near resonances, under the action of a gravitational bar perturbation. A small number of rings may form in response to a mild tidal interaction with a nearby companion. In either case, resonance rings are natural dynamical experiments in star formation stellar association time evolution. We study star formation in two galaxies where resonance rings probably have these two different modes of origin. NGC 3081 has four bi-symmetric star-forming rings that are probably connected to bar-driven gas dynamics, while NGC 4622 is a non-barred spiral where a strong one-sided ring may be connected to a past tidal interaction. We model the young clusters in the rings as two-fold and one-fold periodic orbits, respectively. We show that age indicators, Hα emission and the color index B – I, vary with position angle around the rings in a two-fold and one-fold sense as predicted by our models. The success of these models shows that future high resolution observations can be used to separate the individual associations from the underlying disk light so as to study their evolution and luminosity function.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.