University of Surrey

Test tubes in the lab Research in the ATI Dance Research

The evolution of stellar structures in dwarf galaxies

Bastian, N, Weisz, DR, Skillman, ED, McQuinn, KBW, Dolphin, AE, Gutermuth, RA, Cannon, JM, Ercolano, B, Gieles, M, Kennicutt, RC and Walter, F (2010) The evolution of stellar structures in dwarf galaxies Monthly Notices of the Royal Astronomical Society.

Full text not available from this repository.


We present a study of the variation of spatial structure of stellar populations within dwarf galaxies as a function of the population age. We use deep Hubble Space Telescope/Advanced Camera for Surveys imaging of nearby dwarf galaxies in order to resolve individual stars and create composite colour-magnitude diagrams (CMDs) for each galaxy. Using the obtained CMDs, we select Blue Helium Burning stars (BHeBs), which can be unambiguously age-dated by comparing the absolute magnitude of individual stars with stellar isochrones. Additionally, we select a very young (<10 Myr) population of OB stars for a subset of the galaxies based on the tip of the young main-sequence. By selecting stars in different age ranges we can then study how the spatial distribution of these stars evolves with time. We find, in agreement with previous studies, that stars are born within galaxies with a high degree of substructure which is made up of a continuous distribution of clusters, groups and associations from parsec to hundreds of parsec scales. These structures disperse on timescales of tens to hundreds of Myr, which we quantify using the two-point correlation function and the Q-parameter developed by Cartwright &amp; Whitworth (2004). On galactic scales, we can place lower limits on the time it takes to remove the original structure (i.e., structure survives for at least this long), tevo, which varies between ~100~Myr (NGC~2366) and ~350 Myr (DDO~165). This is similar to what we have found previously for the SMC (~80~Myr) and the LMC (~175 Myr). We do not find any strong correlations between tevo and the luminosity of the host galaxy.

Item Type: Article
Divisions : Surrey research (other units)
Authors :
Bastian, N
Weisz, DR
Skillman, ED
McQuinn, KBW
Dolphin, AE
Gutermuth, RA
Cannon, JM
Ercolano, B
Kennicutt, RC
Walter, F
Date : 9 October 2010
DOI : 10.1111/j.1365-2966.2010.17841.x
Related URLs :
Depositing User : Symplectic Elements
Date Deposited : 17 May 2017 12:40
Last Modified : 24 Jan 2020 22:39

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800