P-MaNGA: Full spectral fitting and stellar population maps from prototype observations
Abstract
MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) is a 6-year SDSS-IV survey that will obtain resolved spectroscopy from 3600 to 10300 for a representative sample of over 10,000 nearby galaxies. In this paper, we derive spatially resolved stellar population properties and radial gradients by performing full spectral fitting of observed galaxy spectra from P-MaNGA, a prototype of the MaNGA instrument. These data include spectra for eighteen galaxies, covering a large range of morphological type. We derive age, metallicity, dust and stellar mass maps, and their radial gradients, using high spectral-resolution stellar population models, and assess the impact of varying the stellar library input to the models. We introduce a method to determine dust extinction which is able to give smooth stellar mass maps even in cases of high and spatially non-uniform dust attenuation. With the spectral fitting we produce detailed maps of stellar population properties which allow us to identify galactic features among this diverse sample such as spiral structure, smooth radial profiles with little azimuthal structure in spheroidal galaxies, and spatially distinct galaxy sub-components. In agreement with the literature, we find the gradients for galaxies identified as early-type to be on average flat in age, and negative (- 0.15 dex / R ) in metallicity, whereas the gradients for late-type galaxies are on average negative in age (- 0.39 dex / R ) and flat in metallicity. We demonstrate how different levels of data quality change the precision with which radial gradients can be measured. We show how this analysis, extended to the large numbers of MaNGA galaxies, will have the potential to shed light on galaxy structure and evolution.
Cite
@article{arxiv.1503.01124,
title = {P-MaNGA: Full spectral fitting and stellar population maps from prototype observations},
author = {David M. Wilkinson and Claudia Maraston and Daniel Thomas and Lodovico Coccato and Rita Tojeiro and Michele Cappellari and Francesco Belfiore and Matthew Bershady and Mike Blanton and Kevin Bundy and Sabrina Cales and Brian Cherinka and Niv Drory and Eric Emsellem and Hai Fu and David Law and Cheng Li and Roberto Maiolino and Karen Masters and Christy Tremonti and David Wake and Enci Wang and Anne-Marie Weijmans and Ting Xiao and Renbin Yan and Kai Zhang and Dmitry Bizyaev and Jonathan Brinkmann and Karen Kinemuchi and Elena Malanushenko and Viktor Malanushenko and Daniel Oravetz and Kaike Pan and Audrey Simmons},
journal= {arXiv preprint arXiv:1503.01124},
year = {2015}
}
Comments
33 pages, including 1 appendix. Accepted for publication in MNRAS