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Boxy/peanut/X bulges, barlenses and the thick part of galactic bars: What are they and how did they form?

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 نشر من قبل Albert Bosma
 تاريخ النشر 2015
  مجال البحث فيزياء
والبحث باللغة English
 تأليف E. Athanassoula




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Bars have a complex three-dimensional shape. In particular their inner part is vertically much thicker than the parts further out. Viewed edge-on, the thick part of the bar is what is commonly known as a boxy-, peanut- or X- bulge and viewed face-on it is referred to as a barlens. These components are due to disc and bar instabilities and are composed of disc material. I review here their formation, evolution and dynamics, using simulations, orbital structure theory and comparisons to observations.



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