학술논문

star formation history of the Sculptor dwarf spheroidal galaxy.
Document Type
Article
Source
Monthly Notices of the Royal Astronomical Society. 8/21/2019, Vol. 487 Issue 4, p5862-5873. 12p.
Subject
*DWARF galaxies
*STAR formation
*ELLIPTICAL galaxies
*DARK energy
*SCULPTORS
*PHOTOMETRY
Language
ISSN
0035-8711
Abstract
We present the star formation history (SFH) of the Sculptor dwarf spheroidal galaxy based on deep g, r photometry taken with Dark Energy Camera at the Blanco telescope, focusing our analysis on the central region of the galaxy extended up to ∼3 core radii. We have investigated how the SFH changes radially, subdividing the sampled area into four regions, and have detected a clear trend of star formation. All the SFHs show a single episode of star formation, with the innermost region presenting a longer period of star formation of ∼1.5 Gyr and for the outermost region the main period of star formation is confined to ∼0.5 Gyr. We observe a gradient in the mean age which is found to increase going towards the outer regions. These results suggest that Sculptor continued forming stars after the reionization epoch in its central part, while in the peripheral region, the majority of stars probably formed during the reionization epoch and soon after its end. From our analysis, Sculptor cannot be considered strictly as a fossil of the reionization epoch. [ABSTRACT FROM AUTHOR]