Abstract
We have created an estimated metallicity map of the SmallMagellanic Cloud (SMC) using the Magellanic Cloud Photometric Survey (MCPS) and Optical Gravitational Lensing Experiment (OGLE III) photometric data. This is a first of its kind map of metallicity up to a radius of ∼2.5°.We identify the Red Giant Branch (RGB) in the V, (V - I) colour-magnitude diagrams of small sub-regions of varying sizes in both data sets. We use the slope of the RGB as an indicator of the average metallicity of a sub-region and calibrate the RGB slope to metallicity using available spectroscopic data for selected sub-regions. The average metallicity of the SMC is found to be [Fe/H]=-0.94 dex (σ[Fe/H] = 0.09) from OGLE III and [Fe/H]=-0.95 dex (σ[Fe/H]=0.08) from MCPS.We confirm a shallowbut significant metallicity gradient within the inner SMC up to a radius of 2.5° (-0.045±0.004 to -0.067±0.006 dex deg-1).
Original language | English |
---|---|
Pages (from-to) | 4279-4297 |
Number of pages | 19 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 475 |
Issue number | 4 |
DOIs | |
Publication status | Published - 2018 Apr 21 |
Bibliographical note
Publisher Copyright:© 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science