We study the internal radial gradients of stellar population properties within 1.5 Re and analyse the impact of galaxy environment.We use a representative sample of 721 galaxies with masses ranging between 109M⊙ and 1011.5M⊙ from the SDSS-IV survey MaNGA. We split this sample by morphology into early-type and late-type galaxies. Using the full spectral fitting code FIREFLY, we derive the light and mass-weighted stellar population properties, age and metallicity, and calculate the gradients of these properties.We use three independent methods to quantify galaxy environment, namely the Nth nearest neighbour, the tidal strength parameter Q and distinguish between central and satellite galaxies. In our analysis, we find that early-type galaxies generally exhibit shallowlight-weighted age gradients in agreement with the literature and mass-weighted median age gradients tend to be slightly positive. Late-type galaxies, instead, have negative light-weighted age gradients. We detect negative metallicity gradients in both early- and late-type galaxies that correlate with galaxy mass, with the gradients being steeper and the correlation with mass being stronger in late-types.We find, however, that stellar population gradients, for both morphological classifications, have no significant correlation with galaxy environment for all three characterizations of environment. Our results suggest that galaxy mass is the main driver of stellar population gradients in both early and late-type galaxies, and any environmental dependence, if present at all, must be very subtle.
|Number of pages||13|
|Journal||Monthly Notices of the Royal Astronomical Society|
|State||Published - Feb 11 2017|
Bibliographical noteFunding Information:
The authors would like to thank Alfonso Aragon-Salamanca, MatthewWithers, Xan Morice-Atkinson for fruitful discussions and Francesco Belfiore for assisting with the Central/Satellite galaxy catalogue. DG is supported by an STFC PhD studentship.MAB acknowledges NSF AST-1517006. AW acknowledges support from a Leverhulme Early Career Fellowship. Numerical computations were done on the Sciama High Performance Compute (HPC) cluster which is supported by the Institute of Cosmology of Gravitation, SEPNet and the University of Portsmouth. Funding for the SDSS IV has been provided by the Alfred P. Sloan Foundation, the US Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. The SDSS web site is www.sdss.org. SDSS-IV is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration including the Brazilian Participation Group, the Carnegie Institution for Science, Carnegie Mellon University, the Chilean Participation Group, the French ParticipationGroup, Harvard-Smithsonian Center forAstrophysics, Instituto de Astrofísica de Canarias, The Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe (IPMU) /University of Tokyo, Lawrence Berkeley National Laboratory, Leibniz Institut fr Astrophysik Potsdam (AIP), Max-Planck-Institut fr Astronomie (MPIA Heidelberg), Max-Planck-Institut fr Astrophysik (MPA Garching), Max-Planck-Institut fr Extraterrestrische Physik (MPE), National Astronomical Observatory of China, New Mexico State University, New York University, University of Notre Dame, Observatrio Nacional/MCTI, The Ohio State University, Pennsylvania State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, Universidad Nacional Autnoma deMéxico, University of Arizona, University of Colorado Boulder, University of Oxford, University of Portsmouth, University of Utah, University of Virginia, University ofWashington, University of Wisconsin, Vanderbilt University, and Yale University. All data taken as part of SDSS-IV is scheduled to be released to the community in fully reduced form at regular intervals through dedicated data releases. The first MaNGA data release was part of the SDSS data release 13 (release date-2016 July 31).
© 2016 The Authors.
- CD&Galaxies: evolution
- Galaxies: elliptical and lenticular
- Galaxies: formation
- Galaxies: spiral
- Galaxies: stellar content
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science