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Abstract: Many barred galaxies show a set of symmetric enhancements at the ends of thestellar bar, called {\it ansae}, or the ``handles- of the bar. The ansa barshave been in the literature for some decades, but their origin has still notbeen specifically addressed, although, they could be related to the growthprocess of bars. But even though ansae have been known for a long time, nostatistical analysis of their relative frequency of occurrence has beenperformed yet. Similarly, there has been no study of the varieties inmorphology of ansae even though significant morphological variations are knownto characterise the features. In this paper, we make a quantitative analysis ofthe occurrence of ansae in barred galaxies, making use of {\it The deVaucouleurs Atlas of Galaxies} by Buta and coworkers. We find that $\sim 40%$of SB0-s show ansae in their bars, thus confirming that ansae are commonfeatures in barred lenticulars. The ansa frequency decreases dramatically withlater types, and hardly any ansae are found in galaxies of type Sb or later.The bars in galaxies with ansae are stronger in the median than those ingalaxies without ansae, but the presence of inner and outer rings is notrelated to the presence of ansae. Implications of these results and theoriesfor the possible origin of ansae are discussed briefly.



Author: I. Martinez-Valpuesta 1,2, J. H. Knapen 1, R. Buta 3 1 Instituto de Astrofisica de Canarias, Tenerife, Spain, 2 Laboratoire d

Source: https://arxiv.org/







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