The APOSTLE simulations: Rotation curves derived from synthetic 21-cm observations

Abstract

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 $10^4{\mathrm{M}}_{\odot }$) using the galaxy formation model and calibration developed for the EAGLE project. I select a sample of dwarf galaxies ($60<V_{\max }/\mathrm{km}{\mathrm{s}}^{-1}<120$) from these simulations and construct synthetic spatially- and spectrally-resolved observations of their 21-cm emission. Using the ${}^{3\mathrm{D}}$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.

To appear in the proceedings of IAUS 334: Rediscovering our Galaxy, July 10-14 2017, Telegrafenberg, Potsdam, Germany, Eds. C. Chiappini, I. Minchev, E. Starkenburg & M. Valentini

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Cited by in corpus (1)

• Observational Evidence of Evolving Dark Matter Profiles at $z\le 1$