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تسجيل مستخدم جديدSimulations of the Milky Ways central molecular zone -- I. Gas dynamics
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We use hydrodynamical simulations to study the Milky Ways central molecular zone (CMZ). The simulations include a non-equilibrium chemical network, the gas self-gravity, star formation and supernova feedback. We resolve the structure of the interstellar medium at sub-parsec resolution while also capturing the interaction between the CMZ and the bar-driven large-scale flow out to $Rsim 5kpc$. Our main findings are as follows: (1) The distinction between inner ($Rlesssim120$~pc) and outer ($120lesssim Rlesssim450$~pc) CMZ that is sometimes proposed in the literature is unnecessary. Instead, the CMZ is best described as single structure, namely a star-forming ring with outer radius $Rsimeq 200$~pc which includes the 1.3$^circ$ complex and which is directly interacting with the dust lanes that mediate the bar-driven inflow. (2) This accretion can induce a significant tilt of the CMZ out of the plane. A tilted CMZ might provide an alternative explanation to the $infty$-shaped structure identified in Herschel data by Molinari et al. 2011. (3) The bar in our simulation efficiently drives an inflow from the Galactic disc ($Rsimeq 3$~kpc) down to the CMZ ($Rsimeq200$~pc) of the order of $1rm,M_odot,yr^{-1}$, consistent with observational determinations. (4) Supernova feedback can drive an inflow from the CMZ inwards towards the circumnuclear disc of the order of $sim0.03,rm M_odot,yr^{-1}$. (5) We give a new interpretation for the 3D placement of the 20 and 50 km s$^{-1}$ clouds, according to which they are close ($Rlesssim30$~pc) to the Galactic centre, but are also connected to the larger-scale streams at $Rgtrsim100$~pc.
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The Milky Ways central molecular zone (CMZ) has emerged in recent years as a unique laboratory for the study of star formation. Here we use the simulations presented in Tress et al. 2020 to investigate star formation in the CMZ. These simulations res
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The nuclear stellar disc (NSD) is, together with the nuclear star cluster (NSC) and the central massive black hole, one of the main components in the central parts of our Milky Way. However, until recently, only few studies of the stellar content of
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