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arXiv · 2006.02071

Stellar Population Synthesis with Distinct Kinematics: Multi-Age Asymmetric Drift in SDSS-IV MaNGA Galaxies

Shravan Shetty·Matthew A. Bershady·Kyle B. Westfall·Michele Cappellari·Niv Drory·David R. Law·Renbin Yan·Kevin Bundy
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Abstract

We present the first asymmetric drift (AD) measurements for unresolved stellar populations of different characteristic ages above and below 1.5 Gyr. These measurements sample the age-velocity relation (AVR) in galaxy disks. In this first paper we develop two efficient algorithms to extract AD on a spaxel-by-spaxel basis from optical integral-field spectroscopic (IFS) data-cubes. The algorithms apply different spectral templates, one using simple stellar populations and the other a stellar library; their comparison allows us to assess systematic errors in derived multi-component velocities, such as template-mismatch. We test algorithm reliability using mock spectra and Monte Carlo Markov Chains on real data from the MaNGA survey in SDSS-IV. We quantify random and systematic errors in AD as a function of signal-to-noise and stellar population properties with the aim of applying this technique to large subsets of the MaNGA galaxy sample. As a demonstration of our methods, we apply them to an initial sample of seven galaxies with comparable stellar mass and color to the Milky Way. We find a wide range of distinct AD radial profiles for young and old stellar populations.

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Shravan Shetty, Matthew A. Bershady, Kyle B. Westfall, Michele Cappellari, Niv Drory, David R. Law, Renbin Yan, Kevin Bundy. 2020-06-03. Stellar Population Synthesis with Distinct Kinematics: Multi-Age Asymmetric Drift in SDSS-IV MaNGA Galaxies. https://doi.org/10.3847/1538-4357%2Fab9b8e

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