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تسجيل مستخدم جديدThe APOSTLE simulations: Rotation curves derived from synthetic 21-cm observations
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تأليف
Kyle A. Oman
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The APOSTLE cosmological hydrodynamical simulation suite is a collection of twelve regions $sim 5$ Mpc in diameter, selected to resemble the Local Group of galaxies in terms of kinematics and environment, and re-simulated at high resolution (minimum gas particle mass of $10^4,{rm M}_odot$) using the galaxy formation model and calibration developed for the EAGLE project. I select a sample of dwarf galaxies ($60 < V_{rm max}/{rm km},{rm s}^{-1} < 120$) from these simulations and construct synthetic spatially- and spectrally-resolved observations of their 21-cm emission. Using the $^{3{rm D}}$BAROLO tilted-ring modelling tool, I extract rotation curves from the synthetic data cubes. In many cases, non-circular motions present in the gas disc hinder the recovery of a rotation curve which accurately traces the underlying mass distribution; a large central deficit of dark matter, relative to the predictions of cold dark matter N-body simulations, may then be erroneously inferred.
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