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New insights on the origin of the High Velocity Peaks in the Galactic Bulge

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 نشر من قبل J. G. Fern\\'andez-Trincado
 تاريخ النشر 2017
  مجال البحث فيزياء
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We provide new insight on the origin of the cold high-V$_{rm los}$ peaks ($sim$200 kms$^{-1}$) in the Milky Way bulge discovered in the APOGEE commissioning data citep{Nidever2012}. Here we show that such kinematic behaviour present in the field regions towards the Galactic bulge is not likely associated with orbits that build the boxy/peanut (B/P) bulge. To this purpose, a new set of test particle simulations of a kinematically cold stellar disk evolved in a 3D steady-state barred Milky Way galactic potential, has been analysed in detail. Especially bar particles trapped into the bar are identified through the orbital Jacobi energy $E_{J}$, which allows us to identify the building blocks of the B/P feature and investigate their kinematic properties. Finally, we present preliminary results showing that the high-V$_{rm los}$ features observed towards the Milky Way bulge are a natural consequence of a large-scale textit{midplane} particle structure, which is unlikely associated with the Galactic bar.

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