Abstract
We use a sample of ∼3000 galaxies from the MaNGA MPL-7 internal data release to study the α abundance distribution within low-redshift galaxies. We use the Lick index ratio Mgb/ as an α abundance indicator to study relationships between the α abundance distribution and galaxy properties such as effective stellar velocity dispersion within 0.3 effective radii (σ ∗ ), galaxy environment, and dark matter halo formation time (z f ). We find that (1) all galaxies show a tight correlation between Mgb/ and (2) "old" (Hβ < 3) low-σ ∗ galaxies in high local density environment and inner regions within galaxy groups are enhanced in Mgb/, while "young" (Hβ > 3) galaxies and high-mass galaxies show no or less environmental dependence; (3) "old" galaxies with high-z f show enhanced Mgb/ over low- and medium-z f ; and (4) Mgb/ gradients are close to zero and show dependence on σ ∗ but no obvious dependence on the environment or z f . Our study indicates that stellar velocity dispersion or galaxy mass is the main parameter driving the Mgb/ enhancement, although environments appear to have modest effects, particularly for low- and medium-mass galaxies.
| Original language | English |
|---|---|
| Article number | 63 |
| Journal | Astrophysical Journal |
| Volume | 873 |
| Issue number | 1 |
| DOIs | |
| State | Published - 2019 |
Bibliographical note
Publisher Copyright:© 2019. The American Astronomical Society. All rights reserved..
Funding
This work makes use of data from SDSS-IV. Funding for SDSS-IV has been provided by the Alfred P. Sloan Foundation and Participating Institutions. Additional funding toward SDSS-IV has been provided by the U.S. Department of Energy This work is supported by the National Natural Science Foundation of China No. 11703036 (ZZ). This work is also partly supported by the National Key Basic Research and Development Program of China (No. 2018YFA0404501 to S.M.), by the National Science Foundation of China (grant No. 11333003, 11390372, and 11761131004 to S.M., and 11874057 to C.L.). H.W. is supported by NSFC 11733004, 11522324, and 11421303. The Science, Technology and Facilities Council is acknowledged for support through the Consolidated Grant Cosmology and Astrophysics at Portsmouth, ST/N000668/1.
| Funders | Funder number |
|---|---|
| U.S. Department of Energy EPSCoR | |
| Alfred P Sloan Foundation | |
| National Key Basic Research and Development Program of China | 2018YFA0404501 |
| Science and Technology Facilities Council | ST/N000668/1 |
| National Natural Science Foundation of China (NSFC) | 11733004, 11522324, 11874057, 11333003, 11703036, 11761131004, 11421303, ST/N000668/1, 11390372 |
Keywords
- galaxies: abundances
- galaxies: evolution
- galaxies: general
- galaxies: statistics
- galaxies: stellar content
- galaxies: structure
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science