Multiple ionisation sources in HII regions and their effect on derived nebular abundances (2009)
Ercolano, Barbara, Wesson, Roger, Bastian, Nate
We present a theoretical investigation of the effect of multiple ionisation sources in HII regions on the total elemental abundances derived from the analysis of collisionally excited emission lines....
Bastian, Nate, Trancho, Gelys, Konstantopoulos, Iraklis S., Miller, Bryan W.
We present optical spectroscopy of 16 star clusters in the merging galaxies NGC 4038/39 ("The Antennae") and supplement this dataset with HST imaging. The age and metallicity of each cluster is...
A significant number of intermediate age clusters (1-2 Gyr) in the Magellanic Clouds appear to have multiple stellar populations within them, derived from bi-modal or extended main sequence turn...
The Spatial Evolution of Stellar Structures in the LMC (2008)
Bastian, Nate, Gieles, Mark, Ercolano, Barbara, Gutermuth, Rob
We present an analysis of the spatial distribution of various stellar populations within the Large Magellanic Cloud. We combine mid-infrared selected young stellar objects, optically selected samples...
The Rotating Nuclear Star Cluster in NGC 4244 (2008)
Seth, Anil C., Blum, Robert D., Bastian, Nate, Caldwell, Nelson, Debattista, Victor P., Puzia, Thomas H.
We present observations of the nuclear star cluster in the nearby edge-on spiral galaxy NGC 4244 using the Gemini Near-Infrared Integral Field Spectrograph (NIFS) with laser guide star adaptive...
An alternative method to study star cluster disruption (2008)
Many embedded star clusters do not evolve into long-lived bound clusters. The most popular explanation for this "infant mortality" of young clusters is the expulsion of natal gas by stellar winds and...
Trancho, Gelys, Bastian, Nate, Miller, Bryan W., Schweizer, François
We present Gemini optical spectroscopy of 23 young star clusters in NGC3256. We find that the cluster ages range are from few Myr to ~150 Myr. All these clusters are relatively massive (2--40)x...
Trancho, Gelys, Bastian, Nate, Schweizer, Francois, Miller, Bryan W.
We present Gemini optical spectroscopy of three young star clusters in the western tidal tail of NGC3256. Compact star clusters (as opposed to dwarf-galaxy candidates) in tidal tails are rare, with...
Cluster Disruption: Combining Theory and Observations (2006)
We review the theory and observations of star cluster disruption. The three main phases and corresponding typical timescales of cluster disruption are: I) Infant Mortality (~10^7 yr), II) Stellar...
Gas expulsion and the destruction of massive young clusters (2006)
Goodwin, Simon P., Bastian, Nate
We examine the luminosity and dynamical mass estimates for young massive stellar clusters. For many young (
Ercolano, Barbara, Bastian, Nate
Emission line spectra from HII regions are often used to study properties of the gas in star-forming regions, as well as temperatures and luminosities of the ionising sources. Empirical diagnostics...
Kissler-Patig, Markus, Jordan, Andres, Bastian, Nate
At which masses does the regime of globular clusters end and the one of dwarf galaxies begin? And what separates these two classes of hot stellar systems? We examine to what extend very massive...
Gieles, Mark, Larsen, Soeren, Bastian, Nate, Stein, Ilaan
We introduce a method to relate a possible truncation of the star cluster mass function at the high mass end to the shape of the cluster luminosity function (LF). We compare the observed LFs of five...
Gieles, Mark, Larsen, Soeren, Scheepmaker, Remco, Bastian, Nate, Haas, Marcel, Lamers, Henny
We present the luminosity function (LF) of star clusters in M51 based on HST/ACS observations taken as part of the Hubble Heritage project. The clusters are selected based on their size and with the...
Hierarchical Star Formation in M51: Star/Cluster Complexes (2005)
Bastian, Nate, Gieles, Mark, Efremov, Yuri N.
We report on a study of young star cluster complexes in the spiral galaxy M51. Recent studies have confirmed that star clusters do not form in isolation, but instead tend to form in larger groupings...
The Star Cluster Population of M51: III. Cluster disruption and formation history (2005)
Gieles, Mark, Bastian, Nate, Lamers, Henny, Mout, Jacqueline
In this work we concentrate on the evolution of the cluster population of the interacting galaxy M51 (NGC 5194), namely the timescale of cluster disruption and possible variations in the cluster...
Lamers, Henny, Gieles, Mark, Bastian, Nate, Baumgardt, Holger, Kharchenko, Nina, Zwart, Simon Portegies
We present a simple analytical description of the disruption of star clusters in a tidal field, which agrees excellently with detailed N-body simulations. The analytic expression can be used to...
The Missing Link in Star Cluster Evolution (2002)
De Grijs, Richard, Bastian, Nate
The currently most popular models for the dynamical evolution of star clusters predict that the power-law Cluster Luminosity Functions (CLFs) of young star cluster systems will be transformed rapidly...
De Grijs, Richard, Bastian, Nate
ABRIDGED: We obtain new age and mass estimates for the star clusters in M82's fossil starburst region B, based on improved fitting methods. Our new age estimates confirm the peak in the age histogram...
Lentz, Eric J., Baron, E., Lundqvist, Peter, Branch, David, Hauschildt, Peter H., Fransson, Claes, ...
We present spectral analysis of early observations of the Type IIn supernova 1998S using the general non-local thermodynamic equilibrium atmosphere code \tt PHOENIX}. We model both the underlying...