Star formation history and environment of the dwarf galaxy UGCA 92
Lidia Makarova, Dmitry Makarov, Sergey Savchenko
TL;DR
This study reconstructs the star formation history of dwarf galaxy UGCA 92, revealing ancient and recent star formation episodes, their metallicities, and clarifying its independence from nearby starburst galaxy NGC 1569.
Contribution
First detailed star formation history of UGCA 92 using HST data, showing its ancient and ongoing star formation and independence from NGC 1569.
Findings
Main star formation occurred 8-14 Gyr ago with low metallicity.
Recent star formation started about 1.5 Gyr ago and continues today.
UGCA 92's star formation history is independent of NGC 1569.
Abstract
We present a quantitative star formation history of the nearby dwarf galaxy UGCA 92. This irregular dwarf is situated in the vicinity of the Local Group of galaxies in a zone of strong Galactic extinction (IC 342 group of galaxies). The galaxy was resolved into stars with HST/ACS including old red giant branch. We have constructed a model of the resolved stellar populations and measured the star formation rate and metallicity as function of time. The main star formation activity period occurred about 8 - 14 Gyr ago. These stars are mostly metal-poor, with a mean metallicity [Fe/H] ~ -1.5 -- -2.0 dex. About 84 per cent of the total stellar mass was formed during this event. There are also indications of recent star formation starting about 1.5 Gyr ago and continuing to the present. The star formation in this event shows moderate enhancement from ~ 200 Myr to 300 Myr ago. It is very…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.