Abstract
We derive the spatially resolved star formation history (SFH) for a 96 deg2 area across the main body of the Large Magellanic Cloud (LMC), using the near-infrared photometry from the VISTA survey of the Magellanic Clouds (VMC). The data and analyses are characterized by a great degree of homogeneity and a low sensitivity to the interstellar extinction. 756 subregions of size 0.125 deg2 - corresponding to projected sizes of about 296 x 322 pc2 in the LMC - are analysed. The resulting SFH maps, with typical resolution of 0.2-0.3 dex in logarithm of age, reveal main features in the LMC disc at different ages: the patchy star formation at recent ages, the concentration of star formation on three spiral arms and on the Bar up to ages of ∼1.6 Gyr, and the wider and smoother distribution of older populations. The period of most intense star formation occurred roughly between 4 and 0.5 Gyr ago, at rates of ∼0.3M⊙yr-1. We compare young and old star formation rates with the observed numbers of RR Lyrae and Cepheids. We also derive a mean extinction and mean distance for every subregion, and the plane that best describes the spatial distribution of the mean distances. Our results cover an area about 50 percent larger than the classical SFH maps derived from optical data. Main differences with respect to those maps are lower star formation rates at young ages, and a main peak of star formation being identified at ages slightly younger than 1 Gyr.
Original language | English |
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Pages (from-to) | 245-266 |
Number of pages | 22 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 508 |
Issue number | 1 |
DOIs | |
Publication status | Published - Nov 2021 |
Bibliographical note
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society, Volume 508, Issue 1, November 2021, Pages 245–266, https://doi.org/10.1093/mnras/stab2399. Copyright 2021 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Keywords
- galaxies: evolution
- Magellanic Clouds
- galaxies: structure