Navigation auf zora.uzh.ch

Search ZORA

ZORA (Zurich Open Repository and Archive)

The ACS LCID Project. III. The Star Formation History of the Cetus dSph Galaxy: A Post-reionization Fossil

Monelli, M; et al; Mayer, L (2010). The ACS LCID Project. III. The Star Formation History of the Cetus dSph Galaxy: A Post-reionization Fossil. Astrophysical Journal, 720(2):1225-1245.

Abstract

We use deep HST/ACS observations to calculate the star formation history (SFH) of the Cetus dwarf spheroidal (dSph) galaxy. Our photometry reaches below the oldest main-sequence turnoffs, which allows us to estimate the age and duration of the main episode of star formation in Cetus. This is well approximated by a single episode that peaked roughly 12 ± 0.5 Gyr ago and lasted no longer than about 1.9 ± 0.5 Gyr (FWHM). Our solution also suggests that essentially no stars formed in Cetus during the past 8 Gyr. This makes Cetus' SFH comparable to that of the oldest Milky Way dSphs. Given the current isolation of Cetus in the outer fringes of the Local Group, the dominant old population implies that Cetus is a clear outlier in the morphology-Galactocentric distance relation that holds for the majority of the Milky Way dwarf satellites. Our results also show that Cetus continued forming stars until zsime 1, long after the universe was reionized, and that there is no clear signature of the epoch of reionization in Cetus' SFH. We briefly discuss the implications of these results for dwarf galaxy evolution models. Finally, we present a comprehensive account of the data reduction and analysis strategy adopted for all galaxies targeted by the LCID (Local Cosmology from Isolated Dwarfs) project. We employ two different photometry codes (DAOPHOT/ALLFRAME and DOLPHOT), three different SFH reconstruction codes (IAC-pop/MinnIAC, MATCH, and COLE), and two stellar evolution libraries (BaSTI and Padova/Girardi), allowing for a detailed assessment of the modeling and observational uncertainties.
Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. These observations are associated with program 10505.

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Astrophysics
Dewey Decimal Classification:530 Physics
Scopus Subject Areas:Physical Sciences > Astronomy and Astrophysics
Physical Sciences > Space and Planetary Science
Language:English
Date:September 2010
Deposited On:02 Mar 2011 09:35
Last Modified:05 May 2025 01:36
Publisher:Institute of Physics Publishing
ISSN:0004-637X
OA Status:Hybrid
Publisher DOI:https://doi.org/10.1088/0004-637X/720/2/1225
Related URLs:http://arxiv.org/abs/1002.4300
Download PDF  'The ACS LCID Project. III. The Star Formation History of the Cetus dSph Galaxy: A Post-reionization Fossil'.
Preview
  • Content: Accepted Version

Metadata Export

Statistics

Citations

Dimensions.ai Metrics
145 citations in Web of Science®
143 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

94 downloads since deposited on 02 Mar 2011
13 downloads since 12 months
Detailed statistics

Authors, Affiliations, Collaborations

Similar Publications