SDSS-IV MaNGA: Variation of the Stellar Initial Mass Function in Spiral and Early-type Galaxies

Research output: Contribution to journalArticle

  • External authors:
  • Hongyu Li
  • Junqiang Ge
  • Shude Mao
  • Michele Cappellari
  • Ran Li
  • Eric Emsellem
  • Aaron A. Dutton
  • Cheng Li
  • Kevin Bundy
  • Daniel Thomas
  • Niv Drory
  • Alexandre Roman Lopes

Abstract

We perform Jeans anisotropic modeling (JAM) on elliptical and spiral galaxies from the MaNGA DR13 sample. By comparing the stellar mass-to-light ratios estimated from stellar population synthesis and from JAM, we find a systematic variation of the initial mass function (IMF) similar to that in the earlier ATLAS3D results. Early-type galaxies (elliptical and lenticular) with lower velocity dispersions within one effective radius are consistent with a Chabrier-like IMF, while galaxies with higher velocity dispersions are consistent with a more bottom-heavy IMF such as the Salpeter IMF. Spiral galaxies have similar systematic IMF variations, but with slightly different slopes and larger scatters, due to the uncertainties caused by the higher gas fractions and extinctions for these galaxies. Furthermore, we examine the effects of stellar mass-to-light ratio gradients on our JAM modeling, and we find that the trends become stronger after considering the gradients.

Bibliographical metadata

Original languageEnglish
Article number77
JournalAstrophysical Journal
Volume838
Issue number2
Early online date29 Mar 2017
DOIs
StatePublished - 2017