Gas flows and bars in galaxies
نویسنده
چکیده
Dynamical evolution of spiral galaxies is strongly dependent on nonaxisymmetric patterns that develop from gravitational instabilities, either spontaneously or externally triggered. Some evolutionary sequences are described through which a galaxy could possibly concentrate mass and build bulges, how external gas accretion from cosmic filaments could be funneled to the galaxy disks, and intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The frequency of both bars and lopsidedness can be used to constrain the gas accretion rate.
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تاریخ انتشار 2006